ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Publication Date: 2018-05-24
    Description: Key Points The coagulation protease FVIIa attenuates TNF-α- and LPS-induced inflammation both in vitro and in vivo via an EPCR-dependent mechanism. FVIIa-EPCR-PAR1-mediated anti-inflammatory signaling transmits through the β-arrestin-1-dependent pathway.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2018-11-29
    Description: Introduction Effective therapies for R/R AML remain limited. MEK or MDM2 inhibition can downregulate MCL1, overcoming resistance to BCL2 inhibition. Preclinical synergy was seen when combining BCL2 inhibitor Ven with MEK inhibitor cobimetinib (cobi) or MDM2 inhibitor idasa (Han et al. ASH 2016; Pan et al. Cancer Cell 2017), supporting clinical evaluation in AML. Preliminary data in a Phase Ib dose-escalation study (NCT02670044) evaluating Ven+cobi/idasa in R/R AML suggested both combinations were tolerable (Daver et al. ASH 2017). However, Ven+cobi was closed due to limited clinical activity. Here we present data for additional pts, longer follow-up and biomarker analyses for Ven+idasa. Methods This ongoing, open-label, multicenter study evaluates safety, tolerability and efficacy of Ven+idasa in R/R AML or secondary AML previously treated for an antecedent hematologic disease. Pts 〉60 yrs of age and ineligible for cytotoxic therapy/allogeneic stem cell transplant were enrolled. A 2-dimensional dose escalation was used to establish the maximum tolerated dose: pts received doses of Ven orally (PO) daily (400mg or 600mg) + idasa PO daily on Days 1-5 (150mg, 200mg, or 400mg) in 28-day cycles. Plasma samples were taken for PK analysis at Cycles 1 and 2 Days 1 and 5, and Cycle 4 Day 1. BCL2, BCLxL and MCL1 status and minimal residual disease (MRD) were assayed centrally at Covance Laboratories using multicolor flow cytometry. Mutation (mut) sequencing was performed by Foundation Medicine using FoundationOne Heme at screening and from last bone marrow collected on study. Results As of April 6 2018, 34 pts received Ven+idasa across all dose cohorts (Table 1). Median age: 74 (range 64-93) yrs; median prior therapies: 1 (range 1-4); ECOG performance status 2: 18%; refractory: 56%; secondary AML: 53%; adverse cytogenetics: 27%. Pre-therapy mut data were available for 32 pts; most common muts were RUNX1 14 (41%), ASXL1 11 (32%), SRSF2 11 (32%). Other significant pre-therapy muts: TP53 6 (18%), IDH2 7 (21%), IDH1 1 (3%), FLT3 4 (13%). The most common adverse events (AEs) were diarrhea (88%) and nausea (71%); the most common grade (Gr) ≥3 AEs were neutropenia (32%), febrile neutropenia (32%), thrombocytopenia (29%; Table 2). After 2 cases of Gr 3 diarrhea in the Ven 600mg cohorts, mandatory prophylaxis was implemented; no further cases of Gr ≥3 diarrhea were seen in the following 10 pts. Laboratory tumor lysis syndrome occurred in 3 pts (9%); none required treatment discontinuation. There was no apparent PK drug-drug interaction between Ven and idasa. PK was dose-proportional over the ranges tested for Ven and idasa. The recommended Phase II dose (RP2D) has not been identified yet. Across all dose cohorts, 30/34 pts were response-evaluable; the remaining 4 were still on study treatment without post-baseline response assessment. The anti-leukemic response rate (CR+CRp+CRi+MLFS+PR) was 37% (11/30). Across the 2 Ven 600mg cohorts, which are being considered for RP2D, the anti-leukemic response rate was 9/18 (50%) (Table 1, Figure 1). MRD negativity (
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2019-11-13
    Description: Tissue factor (TF), an integral membrane glycoprotein, is a cofactor for coagulation factor VIIa (FVIIa) and primary cellular initiator of the coagulation. Upon vascular injury or in disease conditions, blood comes in contact with TF, and the formation of TF-FVIIa complex initiates activation of the coagulation cascade. While TF is critical for the maintenance of hemostasis, aberrant expression of TF activity could lead to thrombotic disorders. Typically, most of TF on cell surfaces exist in a cryptic, coagulant inactive state, and an "activation" step (decryption) is essential for the transformation of cryptic TF to prothrombotic TF. Our recent studies showed that sphingomyelin (SM) in the outer leaflet of the plasma membrane is responsible for maintaining TF in an encrypted state in resting cells. The hydrolysis of SM, by either bacterial sphingomyelinase (bSMase) or acid-sphingomyelinase (ASMase) translocated from lysosomes to the outer leaflet in response to ATP, LPS or cytokine stimulation, increased TF activity on intact cells without altering TF protein levels. SM hydrolysis also led to the release of TF+ microvesicles (MVs). Inhibition of ASMase by functional inhibitors blocked LPS-induced TF procoagulant activity without impairing LPS-induced TF antigen levels in both in vitro and in vivo model systems. SM levels in the plasma membrane are regulated primarily by SM synthesizing enzymes, such as sphingomyelin synthases (SMS) 1 and 2 or SM hydrolyzing enzymes, such as ASMase and neutral SMases (nSMase). Many disease conditions, including diabetes, ischemia/hypoxia, and cancer, alter SM metabolism by altering the activities of the above enzymes. These diseases are also known to have increased thrombotic risk. To investigate the importance of SM metabolism in regulating TF procoagulant activity through TF encryption and decryption, we either overexpressed or silenced the enzymes involved in SM metabolism and determined their effect on TF procoagulant activity on intact cells and the release of TF+ MVs. Human monocyte-derived macrophages (MDMs) or human embilical vein endothelial cells (HUVEC) were chosen as cell model systems. In the first set of experiments, MDMs were transfected with adenovirus encoding SMS1, SMS2, or both to overexpress SMS. Analysis of SM levels in the outer leaflet by confocal microscopy and flow cytometry using SM specific binding protein (lysenin) revealed that overexpression of SMS1 or SMS2 increased SM levels in the outer leaflet. Measurement of TF activity on intact cells showed that overexpression of either SMS1 or SMS2 reduced both basal TF activity and the extent of increased TF activity following ATP or bSMase treatment. Overexpression of SMS1 or SMS2 also decreased the release of TF+ MVs. Overexpression of SMS1 or SMS2 had no significant effect on TF antigen levels. In the next set of experiments, MDMS were transfected with control scrambled RNA (scRNA) or siRNA specific for ASMase, nSMase1, nSMase2, or nSMase3. As expected from our earlier studies, ASMase silencing attenuated both basal and ATP-induced increased TF activity in MDMs. In case of nSMases, the knock-down of nSMase2 or nSMase3, but not nSMase1, reduced basal TF activity as well as ATP-induced TF decryption in MDMs. Analysis of SM levels in the outer leaflet showed that silencing of ASMase, nSMase2, or nSMase3 enhanced the SM content. The knock-down of either ASMase or nSMases did not affect TF antigen levels. In additional studies, HUVECs were transfected with control scRNA or siRNA specific for nSMase1, nSMAse2, or nSMase3. Forty eight hour post-transfection, HUVECs were stimulated with TNFα (10 ng/ml) plus IL-1β (10 ng/ml) for 6 h to induce TF expression. Analysis of cell surface TF activity showed that silencing nSMase2 or nSMase3, but not nSMase1, attenuated TNFα+IL-1β-induced TF procoagulant activity without decreasing TNFα+IL-1β-induced TF antigen levels. Overall, our data support the hypothesis that alterations in SM metabolism regulate TF procoagulant activity through encryption and decryption. Disclosures Rao: Takeda: Research Funding.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2018-11-29
    Description: Introduction Although CLL minimal residual disease (MRD) status is used in contemporary clinical trials aimed at maximizing response or determining treatment duration, its role as a predictive factor for PFS has only been established following chemoimmunotherapy. In contrast, whether MRD is a valuable tool for treatment choice in the era of novel targeted agents for CLL is unknown. Unlike kinase inhibitors, the BCL2 inhibitor venetoclax does result in undetectable MRD (uMRD). MURANO demonstrated significant PFS benefit for venetoclax + rituximab (VenR) given for a fixed duration vs bendamustine + rituximab (BR) in relapsed/refractory (R/R) CLL. Here we present analysis of peripheral blood (PB) MRD kinetics in relation to PFS in MURANO with long follow up, when all pts have completed therapy. Methods Pts were randomized to VenR (Ven 400mg/d for 2 yrs + R for first 6 mo) or BR (6 mo). Response was assessed clinically using complete blood count and physical exam at follow-up visits. PB MRD was analysed centrally by ASO-PCR and/or flow cytometry at Cycle 4, end of combination therapy (EOCT; mo 9) and every 3 mo thereafter until 3 yrs, then every 6 mo. As strong concordance between PB and bone marrow (BM) MRD with VenR was previously shown (Hillmen et al. ASCO 2018), we focus on PB MRD. Pts were categorized into uMRD (
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2018-11-29
    Description: Introduction The measurement, analysis, and communication of treatment-related symptoms and their impact on the functioning of individuals in clinical trials is an area of interest to the medical community, the Food and Drug Administration and other regulatory agencies. Inclusion of GAs and PROs in early phase trials can characterize the heterogeneity of aging and guide development of therapies to benefit older adults. Despite evidence that GAs and PROs are feasible and predictive of outcome, few early phase trials have integrated them to inform on treatment tolerance. The aim of this analysis is to describe changes in GAs and PROs among older adults with R/R AML in a Phase 1b trial of BCL2 inhibitor venetoclax (Ven) with either MEK inhibitor cobimetinib (cobi) or MDM2 antagonist idasanutlin (idasa) (NCT02670044). Methods Patients (pts) aged ≥60 yrs who were ineligible for cytotoxic therapy/allogeneic stem cell transplant were enrolled in this open-label, multicenter study, designed to evaluate the safety, tolerability, and efficacy of Ven+cobi/idasa in R/R or secondary AML. GA measures were Short Physical Performance Battery (SPPB; gait speed, balance tests, chair stands), Hematopoietic Cell Transplant-Comorbidity Index (HCT-CI) and Short Blessed Orientation Test (SBOT). Treatment-related symptoms were assessed via the PRO version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE), administered electronically throughout treatment. GAs were administered at screening, Cycle (C) 2 Day (D) 1, C3D1, and C7D1; PRO-CTCAE was administered at C1D1, weekly during C1, for the first 3 weeks of C2 and C3, and monthly starting at C4D1. Mean GA scores were calculated over time for each treatment arm and pt-level heatmaps were created. The 'frequency', 'severity', 'interference', and 'presence' of PRO-CTCAE symptoms were reported at each assessment, with a longitudinal analysis to understand how symptoms changed over the course of treatment. Results As of April 6 2018, 64 pts had been treated with either Ven+cobi or Ven+idasa. Baseline characteristics were comparable between arms; respectively: median age, 72, 74 yrs; ECOG performance status 0-1, 83%, 82%; refractory disease, 63%, 56%. GA and PRO data were available in 52 and 38 pts, respectively. Screening of GAs identified a physically frail (mean SPPB score 75% and 〉50% reported 'none' or 'mild' decreased appetite and fatigue, respectively. In both arms, pt numbers reduced over C1-3, with 8 pts in the Ven+cobi and 6 pts in the Ven+idasa arms providing data at C3D1; this was largely due to attrition on study. Pts reported that their worst post-baseline symptom was 'frequent' or 'almost constant' symptoms of nausea (55%), diarrhea (71%), and vomiting (5%) at some point, and 'severe' or 'very severe' decreased appetite (55%) or fatigue (55%). Variations in the worst post-baseline symptoms were observed between treatment arms, although this was not statistically tested. Symptoms tended to increase and decrease with the start and end of each treatment cycle and appeared worse during C1 for Ven+cobi (Figure 1). Despite differences in symptoms during the cycle, there did not appear to be changes in mean SPPB scores from baseline to C2, no cognitive impairment during treatment, and little to no increase in comorbidity burden. These results may be influenced by a reduction in pt numbers in each treatment arm over subsequent assessments. Conclusion PROs from this Phase 1b study indicate an increased frequency of treatment-related symptoms, in particular, nausea, diarrhea, vomiting, decreased appetite and fatigue, in older AML pts treated with Ven+cobi or Ven+idasa compared with pre-treatment. PROs and GAs can provide additional complementary insight into the older pt's treatment experience on early phase clinical trials that can inform design of later-phase studies. However, strategies to address missing data will be important for maximizing value gained. Disclosures Klepin: Genentech Inc: Consultancy. Campinha-Bacote:Genentech Inc: Employment. Hong:Genentech Inc/Roche: Employment, Other: Ownership interests PLC. Phuong:Genentech Inc: Employment, Equity Ownership, Other: Ownership interests PLC. Wang:Genentech Inc: Employment; F. Hoffmann-La Roche Ltd: Equity Ownership. Mobasher:F. Hoffmann-La Roche Ltd: Other: Ownership interests non-PLC; Genentech Inc: Employment. Trask:Genentech Inc: Employment; F. Hoffmann-La Roche: Employment.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2000-01-15
    Description: A novel glass needle–mediated microinjection method for delivery of macromolecules, including proteins and larger transgene DNAs, into the nuclei of blood stem/progenitor cells was developed. Temporary immobilization of cells to extracellular matrix–coated dishes has enabled rapid and consistent injection of macromolecules into nuclei of CD34+, CD34+/CD38−, and CD34+/CD38−/Thy-1lo human cord blood cells. Immobilization and detachment protocols were identified, which had no adverse effect on cell survival, progenitor cell function (colony forming ability), or stem cell function (NOD/SCID reconstituting ability). Delivery of fluorescent dextrans to stem/progenitor cells was achieved with 52% ± 8.4% of CD34+ cells and 42% ± 14% of CD34+/CD38−cells still fluorescent 48 hours after injection. Single-cell transfer and culture of injected cells has demonstrated long-term survival and proliferation of CD34+ and CD34+/CD38−cells, and retention of the ability of CD34+/CD38− cells to generate progenitor cells. Delivery of DNA constructs (currently ≤ 19.6 kb) and fluorescently labeled proteins into CD34+ and CD34+/CD38− cells was achieved with transient expression of green fluorescent protein observed in up to 75% of injected cells. These data indicate that glass needle–mediated delivery of macromolecules into primitive hematopoietic cells is a valuable method for studies of stem cell biology and a promising method for human blood stem cell gene therapy.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2018-11-29
    Description: Introduction Venetoclax (Ven) is a highly selective oral inhibitor of BCL2, a key regulator of the intrinsic apoptotic pathway, which is constitutively overexpressed in CLL. Efficacy and safety of VenR given for a fixed duration in R/R CLL was evaluated in the randomized Phase III MURANO study compared with standard bendamustine + rituximab (BR). A first pre-planned analysis, when the majority of patients (pts) were still on study treatment (median follow-up 23.8 mo), established a superior PFS of VenR over BR (Seymour et al. NEJM 2018). With all pts having completed therapy, we analysed long-term outcome with a median follow up of 36.0 mo. Methods Pts were randomized to receive 6 cycles of VenR followed by Ven 400mg once daily for a total of 2 yrs, or 6 cycles of BR. Disease status was assessed by CT scan at screening, Cycle (C) 4 and 2−3 mo after end of combination therapy (EOCT). During Ven single agent and at follow-up visits, response was determined by clinical assessment every 3 mo until 3 yrs of follow-up, then every 6 mo thereafter or until PD. PFS status was based on investigator assessment. Peripheral blood (PB) minimal residual disease (MRD) was analysed centrally by ASO-PCR and/or flow cytometry at C4, EOCT and every 3/6 mo thereafter. All p values are descriptive. Results In total, 389 pts were enrolled in VenR (n=194) or BR (n=195) arms. As of May 8 2018, all pts were off treatment. For BR, 154 (79%) had completed 6 cycles. In the VenR arm, 174 (90%) completed the VenR combination phase and 130 (67%) had completed 2 yrs of Ven. The remainder had PD (11%), died (1%), or withdrew due to AEs (15%) or other reason (6%). Median Ven exposure duration and relative dose intensity were 24.4 (range 0-27.9) mo and 97.4% (26-100%), respectively, overall and 17.7 (0.5-21.9) mo and 99% during Ven single-agent therapy. With a median time off Ven after 2 yrs treatment of 9.9 (1.4-22.5) mo, PFS with VenR remains superior to BR (HR, 0.16 [95% CI 0.12, 0.23]; p1% in PB at Mo 24 (when Ven single agent was scheduled to cease) and 10/16 pts had del(17p)/TP53 mutation at baseline. Clinical and cytogenetic risk factors in pts with and without PD after Mo 24 are in Table 1. In this analysis, OS improvement was seen with VenR over BR (HR, 0.50 [95% CI 0.30, 0.85]; p=0.0093; 3-yr rate: 87.9% vs 79.5%; Figure 4). Subsequent CLL-directed treatment was given after PD in 91 pts in the BR arm. 71/91 (78%) BR arm pts received novel targeted agents, including 45 who had ibrutinib and 7 who had Ven. 27/194 (14%) pts in the VenR arm received subsequent therapy: 13/27 (44%) had novel targeted agents as next treatment, including 8 pts who had ibrutinib and 3 who were re-treated with Ven. See Table 2 for a safety overview for VenR combination and Ven single-agent periods. During Ven single agent: 17/171 pts (10%) had an AE leading to drug withdrawal; 7/171 pts (4%) had an AE leading to dose reduction; 44/171 pts (26%) had a Ven dose interruption due to an AE; 7/171 pts (4%) had a fatal AE (4 other cancers, 2 cardiac, 1 pneumonia). Grade 3-4 AEs occurred in 59/171 pts (35%); the most frequent were neutropenia (20 pts, 12%), anemia (5 pts, 3%), and thrombocytopenia (3 pts, 2%). 12/171 (7%) pts had a grade 3-4 infection in the Ven single-agent phase. The total number of Richter transformation events was 7 with VenR and 6 with BR. Conclusions With all pts off treatment and 3 yrs' median follow-up, continued substantial benefit was observed with VenR, with PFS and OS superior to BR. There were no new safety signals; most pts were able to complete treatment. The rate of CLL progression in the first 12 mo after Ven completion was modest (13%), supporting the feasibility and safety of a time-limited VenR duration. The protocol has been amended to include assessment of response and durability of disease control with VenR reintroduction at PD. This updated analysis of this Phase III global randomized study demonstrates clinically meaningful benefit of the VenR chemotherapy-free regimen with a fixed duration in all pts with R/R CLL. Disclosures Seymour: AbbVie: Consultancy, Honoraria, Research Funding; F. Hoffmann-La Roche Ltd: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Genentech Inc: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Research Funding; Celgene: Consultancy. Kipps:Genentech Inc: Consultancy, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Consultancy, Honoraria, Research Funding; Verastem: Membership on an entity's Board of Directors or advisory committees; F. Hoffmann-La Roche Ltd: Consultancy, Research Funding; Celgene: Consultancy; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Verastem: Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pharmacyclics: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Eichhorst:AbbVie, Celgene, Gilead, Janssen, Mundipharma, Novartis, Roche: Honoraria, Other: Travel support, Research Funding. Hillmen:Alexion Pharmaceuticals, Inc: Consultancy, Honoraria; Gilead Sciences, Inc.: Honoraria, Research Funding; Acerta: Membership on an entity's Board of Directors or advisory committees; Pharmacyclics: Research Funding; F. Hoffmann-La Roche Ltd: Research Funding; Novartis: Research Funding; Celgene: Research Funding; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Assouline:Pfizer: Honoraria, Research Funding, Speakers Bureau; Roche: Honoraria, Research Funding, Speakers Bureau; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; BMS: Honoraria, Research Funding, Speakers Bureau. Owen:Teva: Honoraria; Celgene: Research Funding; F. Hoffmann-La Roche Ltd: Honoraria, Research Funding; Merck: Honoraria; AbbVie: Research Funding; Janssen: Honoraria, Research Funding; Pharmacyclics: Research Funding; AstraZeneca: Honoraria, Research Funding. Robak:Janssen: Consultancy, Honoraria; Gilead: Consultancy; AbbVie, Inc: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Consultancy, Honoraria. de la Serna:Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees. Jaeger:Takeda-Millenium: Membership on an entity's Board of Directors or advisory committees; Takeda-Millenium: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; Mundipharma: Membership on an entity's Board of Directors or advisory committees; Bioverativ: Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; GSK: Membership on an entity's Board of Directors or advisory committees; MSD: Research Funding; AOP Orphan: Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Infinity: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; AbbVie: Consultancy, Honoraria; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Cartron:Gilead Sciences: Honoraria; Celgene: Consultancy, Honoraria; Janssen: Honoraria; Roche: Consultancy, Honoraria; Sanofi: Honoraria. Montillo:Gilead: Consultancy, Honoraria, Speakers Bureau; Janssen: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria, Speakers Bureau; Roche: Consultancy, Honoraria, Research Funding. Lamanna:Acerta: Research Funding; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Jannsen: Consultancy, Membership on an entity's Board of Directors or advisory committees; Verastem: Research Funding; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; AstraZeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; TG Therapeutics: Research Funding; Pharmacyclics: Consultancy, Membership on an entity's Board of Directors or advisory committees. Verdugo:AbbVie, Inc: Employment, Equity Ownership. Punnoose:Genentech Inc: Employment; Roche: Equity Ownership. Jiang:Genentech Inc: Employment, Equity Ownership. Wang:Genentech Inc: Employment; F. Hoffmann-La Roche Ltd: Equity Ownership. Boyer:F. Hoffmann-La Roche Ltd: Employment, Equity Ownership. Humphrey:F. Hoffmann-La Roche Ltd: Employment, Equity Ownership. Mobasher:F. Hoffmann-La Roche Ltd: Other: Ownership interests non-PLC; Genentech Inc: Employment. Kater:Abbvie: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Research Funding; Acerta: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche/Genentech: Membership on an entity's Board of Directors or advisory committees, Research Funding.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2015-09-17
    Description: Key Points tmTNF-α expressed on LSC and leukemia cells correlates with poor risk stratification and adverse clinical parameters. Targeting tmTNF-α by monoclonal antibody eradicates LSC and blasts, preventing leukemia regeneration in secondary transplant in NOD-SCID mice.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2018-11-29
    Description: Background : FLT3-ITD mutation remains a great challenge in treating acute myeloid leukemia (AML) patients, for the high incidence of early relapse and drug-resistant mutations to tyrosine kinase inhibitors (TKIs). The FLT3-ITD mutation results in a significant and sustained activation of downstream signaling pathways. However, the physiological negative regulators of those aberrantly activated pathways have not been fully elucidated. In this study, we aim to identify and exploit a key molecule directly interacting with FLT3 receptor and down-regulating FLT3 associated pathways. Methods: The potential proteins interacting with FLT3 were immunoprecipitated (IP) and screened by mass spectrometry. The binding of phosphatase SHP-1 and FLT3 was verified using co-IP and in situ proximity ligation assay (PLA) in cell lines and primary samples. The phosphatase activity and phosphorylation level of SHP-1 was determined by pNPP phosphatase activity assay and western blot. Biological effects of overexpressed SHP-1 by lentiviral vectors in AML cell-lines were assessed using proliferation, apoptosis and clonal formation assays in vitro and xenografts models in vivo. Plasmids of truncated or mutated structure of SHP-1 were constructed and overexpressed in cells to identify the key domain responsible for binding with FLT3 receptor. An artificial trans-membrane peptide was designed to activate SHP-1 activity and promote apoptosis in AML cells. Results: The researchers performed immunoprecipitations (IP) followed by LC-MS/MS based screen in human leukemia cell line MV4-11 for three times, and found that the phosphatase SHP-1 binds to FLT3. In addition, the interaction between SHP-1 and FLT3-WT or FLT3-ITD was verified by co-IP and in situ proximity ligation assay (PLA) in AML cell lines, primary samples and overexpression model of 293-FT.Partial results are showed in Figure A. Furthermore, in heterozygous cell line molm13 and engineered FLT3-ITD knock-in cell line SKM-1 by crispr/cas9 techonology, combined with PLA, pNPP phosphatase activity assay and western blot, we found that SHP-1 may bind with p-FLT3 and acquired phosphatase activity(Figure B-D). In turn, p-FLT3 itself and some important proteins in the downstream pathway would be dephosphorylated and the signal transmission would be terminated. In FLT3-ITD cells, the phosphorylation level of SHP-1 significantly reduced. By using lentivirus to overexpress or knockdown shp-1 protein in FLT3-WT and FLT3-ITD cells, the biological effects were studied. Experiments on cell apoptosis, proliferation and clonal formation have shown that overexpression of SHP-1 in AML cells may promote apoptosis, inhibit proliferation and clone formation, especially in FLT3-ITD cells. On the contrary, inhibition of shp-1 could promote proliferation and increase the ability of clone formation. Furthermore, DOX-inducible overexpression cell line of SHP-1 was obtained by tet-on virus system and the western blots showed that SHP-1 may inhibit p-ERK and p-STAT5 activity. In vivo experiments of NCG mice showed that, the degree of leukemia infiltration in peripheral blood was decreased in AML transplantation mice induced by DOX to express SHP-1 when compared to control group. Next, according to the analysis of protein structure by computer simulation, we constructed truncated and mutated plasmids and overexpressed in cells, then using PLA to verify the binding , we found that FLT3 interact with N-SH2 domain of SHP-1,exactly the R30 site(Figure E). Therefore, by using specific trans-membrane peptide, the researchers found that it could activate SHP-1 and promote apoptosis in AML cells, especially FLT3-ITD ones, inhibit cell proliferation and the downstream signal pathway of FLT3.Lastly,injection of peptide in subcutaneous tumor model of nude mouse showed that the tumor was significantly smaller than that of the control group(Figure F). Conclusion: We identify a negative regulator, namely phosphatase SHP-1, which directly interacts with FLT3 receptor through the N-SH2 domain and down-regulates FLT3 downstream signaling pathways. Overexpression of SHP-1 promotes apoptosis and inhibits proliferation in cells with FLT3-ITD mutation. Artificial trans-membrane peptides activating SHP-1 can reverse FLT3 associated aberrant signaling, thus providing a new potential strategy to target FLT3-ITD in AML. The possible mechanism is showed in figure G. Disclosures No relevant conflicts of interest to declare.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2019-11-13
    Description: Introduction: Elderly pts with R/R AML not eligible for cytotoxic therapy have limited therapeutic options, and dismal outcomes with available therapies. In preclinical studies, inhibition of BCL-2 and MDM2 with Ven and Idasa, respectively, has demonstrated potent synergistic apoptotic activity. In this ongoing, open-label, Phase Ib study, the safety, tolerability, and preliminary efficacy of Ven+cobimetinib (Arm A) and Ven+Idasa (Arm B) is being assessed in R/R AML (NCT02670044). Initial analysis indicated a tolerable safety profile for Ven+Idasa. Here, we present updated safety and efficacy results from Arm B. Methods: Pts (≥60 years) with R/R AML or secondary AML, previously treated for an antecedent hematologic disease but treatment naïve for AML, and ineligible for cytotoxic therapy/allogeneic stem cell transplant were enrolled. The maximum tolerated dose of Ven+Idasa was determined by two-dimensional dose escalation. Pts received Ven orally (PO) daily (400 or 600mg) + Idasa PO daily on Days (D) 1-5 (150mg, 200mg, or 400mg) in 28-day cycles. Responses were assessed according to revised International Working Group Response Criteria 2003. Pharmacokinetic (PK) analyses were performed on plasma samples on Cycles (C) 1 and 2, D1 and 5, and C4, D1. Exploratory assessments included minimal residual disease (MRD), assayed centrally at Covance Laboratories using 8-color flow cytometry. Data cut-off was June 21, 2019. Results: At data cut-off, 49 pts were treated with Ven+Idasa. Median age was 72 years (range 62-93); Eastern Cooperative Oncology Group performance status 0-1: 84%; refractory AML: 57%; relapsed AML: 33%; and secondary previously untreated AML: 10%; Intermediate-I or Intermediate-II European Leukemia Net (ELN) risk classification: 66%; adverse ELN classification: 30%; de novo (49%) versus secondary (51%) AML; and median prior lines of treatment: 1 (range 1-4). Most common adverse events (AEs; any grade) irrespective of attribution were diarrhea (90%) and nausea (78%); the most common grade ≥3 AEs were febrile neutropenia (45%), neutropenia (27%), and thrombocytopenia (25%; Table 1). Laboratory tumor lysis syndrome occurred in 3 pts; none resulted in treatment discontinuation. Ven and Idasa treatment discontinuation due to AEs were noted in 18% and 20%, respectively, most commonly due to infections. 30- and 60-day mortality rates were 6% and 17%, respectively. No apparent PK drug-drug interaction was found between Ven and Idasa; overlap in Ven and Idasa exposure was substantial over the doses tested. Anti-leukemic response rate (complete response [CR] + CR with incomplete platelet count recovery [CRp] + CR with incomplete blood count recovery [CRi] + partial response [PR] + morphologic leukemia-free state [MLFS]) across all dose levels was 41% (Table 2). Across the two Ven 600mg cohorts being considered for the recommended Phase II dose (RP2D), the anti-leukemic response rate was 50% (CR+CRp+CRi rate 29%). Median time to CR+CRp+CRi+PR was 1.4 months (range 1-3), with a median response (CR+CRp+CRi) duration of 4.9 months (range 0.6-9.7). Median overall survival in all pts and in the Ven 600mg cohorts was 4.4 months and 5.7 months, respectively, with a median follow-up of 3.4 months (range 0.03-18). Individual pt responses are shown in Figure 1. MRD negativity (
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    Publication Date: 2019-11-13
    Description: Background: Previous studies indicate that patients with relapsed/refractory multiple myeloma (RRMM) who receive BCMA-targeting CAR-T cells may achieve better remission but have a higher relapse rate. Persistence of CAR T cells post-infusion may be one determinant of the duration of response. Moreover, once the disease progresses again, the re-infusion of CAR-T cells is not effective. To solve this dilemma, we have developed a novel BCMA-targeting CAR-T (CT103A) with a lentiviral vector containing a CAR structure with a fully human scFv, CD8a hinger, and transmembrane, 4-1BB co-stimulatory and CD3z activation domains. Methods: ChiCTR1800018137 is a single-center and single-arm trial of CT103A in patients with RRMM (≥ 3 prior lines, including a proteasome inhibitor and an IMiD, or double refractory). The primary objectives are the incidence of adverse events (AEs), including dose-limiting toxicities (DLTs). The secondary objectives are the duration of clinical response, evaluation of minimal residual disease (MRD), progression-free and overall survival, and CAR-T cell persistence in blood. Between September 21, 2018, and August 1st, 2019, sixteen patients (including 4 patients having relapsed after being given a murine BCMA CAR-T and 5 patients having extramedullary disease and/or plasma cell leukemia) received CT103A in 3+3 dose-escalation trial (four doses at 1, 3, 6, 8 ×106/kg) after a conditioning chemotherapy regimen of cyclophosphamide and fludarabine. Median follow-up after CT103A infusion was 195 days (23 to 314 days) and all 16 patients were evaluable for initial (14 days) clinical response. Results: As of August 1st, 2019, the objective response rate was 100%, 6/16 patients achieved CR/sCR within two weeks post-infusion and all 8 patients surpassing 6 months achieved VGPR/CR/sCR. CR/sCR was 75%, and VGPR was 25% for these 8 patients, according to the IMWG Uniform Response Criteria for MM. In 4 patients who have participated in a prior CAR-T trial, three have achieved sCR, and 1 achieved VGPR. All 15 patients who could be evaluated for minimal residual disease (MRD) had MRD-negative status (≤10-4 nucleated cells by flow). The circulating CT103A cells were detected in the blood by flow and digital polymerase chain reaction, peaking at 14 days (ranging from 9 to 25), and remaining detectable in 12/16 patients, at the time of their last evaluation. Patient #1 (the first patient treated) has now exceeded 314 days of CART persistence, post-infusion. All sixteen patients developed cytokine release syndrome (according to ASBMT Consensus Grading for Cytokine Release Syndrome and Neurological Toxicity Associated with Immune Effector Cells: 10 Grade 1-2, 5 Grade 3,1 Grade 4). A grade 4 CRS appeared at the 6×106 /kg dose level and was considered as a dose-limiting toxicity DLT. No neurotoxicity was observed in all dose groups. One patient died of a lung infection 19 days post-infusion. Conclusions: Data from this early-stage clinical study showed the unparalleled safety and efficacy of CT103A in heavily pretreated R/R multiple myeloma patients. Highly active (ORR 100%) and rapid response within two weeks, suggests CT103A could be developed as a competitive therapy to treat patients with RRMM. Disclosures Hu: Nanjing Iaso Biotherapeutics Co. Ltd..: Employment. Yang:Nanjing Iaso Biotherapeutics Co.: Employment. Zhou:Nanjing Iaso Biotherapeutics Co. Ltd.: Other: Chairman of Advisory Committee of Science and Medicine .
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    Publication Date: 2008-11-16
    Description: Objective Aberrant DNA methylation of CpG site is among the earliest and most frequent alterations in cancer. The aim of this study was to study whether phenylhexyl isothiocyanate can reduce the methylation level of P16 gene. This study used a microarray-based method for quantificationally detecting changes of P16 gene methylation in leukemia patient and U266 cell line. And to simply discuss the effect of phenylhexyl isothiocyanate on tumor methylation. Methods This method used bisulfite-modified DNA as a template for PCR amplification, resulting in conversion of unmethylated cytosine, but not methylated cytosine, into thymine within CpG islands of interest. One set of oligonucleotide probes were designed to fabricate a DNA microarray to detect the methylation changes of P16 gene CpG islands. Each set contained a pair of methylated and unmethylated oligonucleotides for interrogating 3 CpG sites in close proximity. By TA cloning, PCR, sequencing, positive and negative DNA targets were required. Next drawing a standard curve by fluorescence intensity. Leukemia samples DNA were abstracted and bisulfite-modified. Sample DNA targets were required by PCR amplification and were hybridized with the microarry. Finally the microarry was scanned with ScanArray Lite microarray analysis systems. Results The linear relationship (R2=0.9660) was established and it could be used to eliminate background noise. The methylation level of U266 is hypermethylation, after cultured with PHI, the level reduce. Eleven patients have P16 gene hypermethylation in thrity. After culture with PHI, seven patients showed level reduce, one patient showed raise, three patients showed remaining. Conclusion PHI can reduce the methylation level of P16 gene in U266 cell line, and also can reduce the methylation level of P16 gene of leukemia patient samples in vitro culture.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Publication Date: 2008-11-16
    Description: Objective Previous researches confirmed that multidrugresistance(MDR) plays an important role in the failure of chemotherapy on malignant tumors. This study was to investigate the molecular biological mechanisms of cyclosporine A(CsA), tetrandrine(Tet) and their combination on multidrug resistance cell line K562/A02. Methods K562/A02 cells were treated with cyclosporine A and (or) tetrandrine. The intracellular DNR concentration and the expression of P-glyco-protein (P-gp) were observed by flow cytometry (FCM) assay. The mRNA expression of mdr-1 was measured by fluorescent semi-quantitative reverse transcriptase polymerase chain reaction(RT-PCR). Resulds CsA and Tet (alone or combination) elevated the intracellular DNR concentration in K562/A02 cells(the fluorescence intensity of intracellelar DNR in K562/A02 cells was 60%,65% and 98% respectively of that in K562 cells); The fluorescence intensity of P-gp in K562 and K562/A02 cells was 0.5% and 97.97%. The P-gp expression was down after treated with CsA,Tet and both(75.32%,76.86% and 48.61%); mdr1 mRNA was also down regulated, and the effect of their combination was greater. Conclusion Multidrug resistance (MDR) can be partially reversed by CsA or Tet, the combination of both drugs shows a great synergistic reversal effect.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Publication Date: 2008-11-16
    Description: Object: To study the variation of p21, P-gp expression in reversion of multidrug resistance of K562/A02 leukemic line with different concentration of tetrandrine(TET), to provide new theoretic evidence for the clinical application of TET. Methods: The IC50 (the concentration causing 50% inhibition of cell growth) of DNR was analyzed by MTT method; The Expressions of p21 were assayed by westernblot; The Expressions of P-gp were assayed by FCM; The expressions of mdr1 were assayed by RT-PCR; The variation of p21 was accentuation with the accrescence concentration of TET(P
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    Publication Date: 2008-11-16
    Description: Objective: To establish the xenograft leukemia model with stable multiple drug resistance in nude mice; to investigate the reversal effect of 5-Bromotetrandrine and Magnetic nanoparticle of Fe3O4 combined with DNR in vivo and to search for the possible reversal mechanisms. Methods: K562 and K562/A02 cells were respectively inoculated subcutaneously into back of athymic nude mice (1×107 cells/each) to establish the xenograft models. The tumor formation was evaluated by animal ultrasonic inspection. Tumors-bearing nude mice were assigned randomly to five groups which were treated with NS (A group); DNR 1mg/kg (B group); nanoparticle of Fe3O4 combined with DNR 0.63mg/kg(C group): 5-BrTet 2.5mg/kg combined with DNR(D group); 5-Bromotetrandrine 2.5mg/kg and Magnetic nanoparticle of Fe3O4 combined with DNR 0.63mg/kg(E group) respectively. The incidence of tumor formation, growth characteristics, weight and volume of tumor were observed. The histopathologic examination of tumors and organs were detected. For resistant tumors, the protein levels of P-glycoprotein (P-gp) were detected by Western blot. Results: The tumor incidence was 100% in the nude mice inoculated with either K562 or K562/A02 cells. In 6 to 9 days,the tumors reached a volume of more than 1 00 mm3. In vivo, MTT assay showed K562/A02 tumor maintained the drug resistance. For K562 cells xenograft tumors, there were no apparent differences in tumor suppression effect between the B AC AD AE group. For K562/A02 cells xenograft tumors, 5-BrTet and Magnetic nanoparticle of Fe3O4 combined with DNR significantly suppressed growth of tumor: the inhibition rate was 62.76% while DNR alone be used, the inhibition rate was 3.68%. Pathologic examination of resistant tumors showed the tumors necrosis obviously in E group. Application of 5-BrTet and Magnetic nanoparticle of Fe3O4 inhibited the overexpression of P-gp. Conclusion: The xenograft leukemia nude mice model was maintain the multiple drug resistance. 5-Bromotetrandrine and Magnetic nanoparticle of Fe3O4 combined with DNR had a significant tumor-suppressing effect on MDR leukemia cells xenograft model.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    Publication Date: 2008-11-16
    Description: Objective To evaluate the MDR reversal activity of magnetic nanoparticle Fe3O4 (Nano-Fe3O4) and 5-bromotetrandrine (BrTet) on multidrug resistance cell line K562/A02 solitarily or symphysially, and to investigate the reversal mechanism of this coopration. Methods The proliferation of K562 and K562/A02 cells which were cultured with daunomycin (DNR) alone or in combination with Nano-Fe3O4, BrTet or both for 48h were evaluated by MTT assay. DNR accumulation and P-gp of K562 and K562/A02 were analyzed by fluorospectrophotometry. Results The IC50 of DNR for K562 and K562/A02 cells were 2.74±0.19μM and 32.33±8.40μM, respectively; but the sensitivity of K562/A02 cells to DNR was partially restored after culturing with Nano-Fe3O4, BrTet solitarily and symphysially (the IC50 were 7.04±0.85μM, 4.25±2.16μM, 1.80±0.30μM; the FR were 4.32, 7.61, 17.96, respectively), but had no effects on K562 cell lines. The differences had statistical significance. Flow cytometry assay showed that Nano-Fe3O4 and BrTet increased the DNR accumulation in K562/A02 cells, especially in the group of synergia of these two agents. The mean fluorescence intensity of endocellular DNR increased from 2614 pretreated with DNR only to 4783 incubated with these two reversal reagents, while the values were 3364, 4077 for incubating with Nano-Fe3O4 and BrTet respectively. P-gp were down regulated through pretreating with Nano-Fe3O4, BrTet alone and symphysially in K562/A02 cells by fluorospectrophotometry assay. Conclusion Nano-Fe3O4 and BrTet synergisticly showed significant MDR reversal activity in vitro. The reversal activity may be related to the inhibition of P-gp overexpression and the increasing of the anticancer drug accumulation intracelluarly.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    Publication Date: 2008-11-16
    Description: Objective: To observe the apoptosis of K562/A02 cells induced by application of Fe3O4-Magnetic Nanoparticle (Fe3O4-MNPs) loaded with Daunorubicin(DNR) and 5-Bromotetrandrine (BrTet) and to explore its possible molecular mechanism. Methods: We detected the apoptosis of K562/A02 cells after treatment with Fe3O4-MNPs and BrTet with DNR alone or their combination by flow cytometry(FCM),Wright staining and DNA ladder. The expression of Bax and Bcl-2 protein was measured by Western blot. Results: The result showed apoptotic characteristics after treated with this composite for 48 hours. Flow cytometry assay showed the percentage of apoptotic cells which were treated with Fe3O4-MNPs and BrTet with DNR alone or their combination for 48 hours increased from (7.9%±0.35)% to (15.5%±0.87)%, (19.7%±1.04)% and(40.8%±1.74)%, (P
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    Publication Date: 2008-11-16
    Description: Object: To the effect of Fe3O4-magnetic nanoparticle loaded with DNR on In order to study the multidrug-resistant reversal effect of Fe3O4-magnetic nanoparticle loaded with DNR in vivo. Methods: K562-n,a leukemia cell line with high tumorigenicity in nude mice and its multidrug-resistant counterpart K562-n/VCR cells were inoculated subcutaneously into each groins of nude mice (5×106 cells/each) to establish a human leukemia xenograft model. The mice were randomly divided into group A receiving normal saline, group B receiving anti-tumor drugs daunorubicin (DNR), group C receiving Fe3O4-magnetic nanoparticle, group D receiving Fe3O4-magnetic nanoparticle loaded with DNR, and group E receiving Fe3O4-magnetic nanoparticle containing DNR with a magnetic field built on the surface of tumor tissues. After 20 days treatments, mice were killed and tumor tissues were isolated for pathological observation. The volume and weight of tumors were measured, then tumor suppression rate was calculated. The side effects of DNR loaded Fe3O4-magnetic nanoparticle were also evaluated. Results: The results showed that DNR loaded Fe3O4-magnetic nanoparticle can significantly suppress the growth of K562-n/VCR tumor in vivo, DNR alone can greatly suppress the growth of K562-n, Fe3O4-magnetic nanoparticle loaded with DNR can not further inhibit the K562-n tumor. Conclusion: In conclusion, Fe3O4-magnetic nanoparticle loaded with DNR can reverse the leukemia multidrug resistance in vivo.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    Publication Date: 2008-11-16
    Description: Objective: To investigate the effect of 6-phenylhexyl isothiocyanate (PHI) on drug resistance and sensitivity on K562/A02 cell line to ADM and elucidate the probable mechanisms. Methods: We measured growth inhibition of ADM on K562/A02 cell line by MTT assay. Apoptosis rate of K562/A02 cell line, the change of intracellular ADM and MRP1 protein level were detected by Flow Cytometry. Intracellular deoxidized GSH by spectrometric enzyme assay and MRP1 mRNA by RT-PCR semiquantitative assay were observed anteroposterior using PHI. Results: PHI can enhance the sensitivity of K562/A02 cell line to ADM, survival rate of K562/A02 cell line decreased with the increasing concentration of PHI and ADM. Apoptosis rate increased with treating by combination of two above drugs, and multiple of drug resistance had statistical significance (P0.05) no matter after or before PHI was used on different concentration. Conlusion: The depletion effect of PHI on the intracellular GSH can not only partly enhance the reverse effect of ADM, but also enhance the sensitivity of K562/A02 cell line to ADM. Such depletion may diminish side effect and treatment dosage of ADM. It provides a new view to the therapy of leukaemia.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    Publication Date: 2008-11-16
    Description: Objective: To study the reversal effect of Tetrandrine(Tet) and the estrogen-receptor inhibitor,toremifene(Tor),on multidrug resistance cell line K562/A02 and to investigate the reversal mechanism of this combination. Methods: ADM accumulation and the apoptosis percentage of K562 and K562/A02 cells were analyzed by fluorospectrophotometry, respectively. The protein levels of P-glycoprotein (P-gp) were detected by fluorospectrophotometry. The mRNA levels of mdr1 and Survivin were determined by RT-PCR. Results: The IC50 of ADM for K562/A02 and K562 cells were 57.43±4.55mg/L and 1.16±0.05mg/L respectively. Pretreating K562/A02 cells with toremifene(2.5μmol/L) or Tet(1μmol/L) for 72 hours partially restored the sensitivity of K562/A02 cells to ADM (IC50 were 20.74±1.62mg/L and 14.12±1.20mg/L respectively) but had no effect on K562 cells; IC50 of combined tetrandrine and toremifene was 9.14±1.03mg/L;K562/A02 showed apoptotic characteristics after treated with tetrandrine, toremifene (alone or combination);tetrandrine and toremifene (alone or combination) elevated the intracellular ADM accumulation in K562/A02; P-gp, mdr1 and Survivin mRNA were down regulated. Conclusion: Tetrandrine, toremifene (alone or combination) showed significant MDR reversal activity in vitro The reversal activity may be related to the inhibition of P-gp overexpression and down regulation the expression of mdr1 and Survivin mRNA to increase the intracellular accumulation of anticancer drugs, which lead to more K562/A02 cells apoptosis; Multidrug resistance (MDR) can be partially reversed by Tet or Tor of which the combination shows a great synergistic reversal effect.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Publication Date: 2008-11-16
    Description: Object: To the effect of Fe3O4-magnetic nanoparticle loaded with DNR on multidrugresistant K562 cells in vivo. Methods: K562-n and its MDR counterpart K562-n/VCR cell were inoculated subcutaneously into both sides of the back of nude mice (5×106 cells/each) to establish a human leukemia xenograft model. The mice were randomly divided into group A receiving normal saline every other day for 20days, group B receiving DNR every other day for 20days, group C receiving Fe3O4-magnetic nanoparticle every other day for 20days, group D receiving Fe3O4-magnetic nanoparticle loaded with DNR every other day for 20days, and group E receiving Fe3O4-magnetic nanoparticle containing DNR every other day for 20days with a magnetic field built on the surface of the tumor tissue. The tumor volume was measured on the day 1, 5, 9, 13, 17 and 21d after the first treatment. Tumor tissues were isolated for examination of the expression of mdr-1, bcl-2, bax and caspase-3 by reverse transcription polymerase chain reaction and Western blotting. Results: For K562-n/VCR tumor, the tumor volume was markedly lower in groups D and E than in groups A, B and C (group D or E vs group A, B or C, P 〈 0.05). The transcription of mdr-1 and Bcl-2 gene was significantly lower in groups D and E than in groups A, B and C (group D or E vs group A, B or C, P 〈 0.05). So did the protein expression of Bcl-2. However, there were no differences among these groups about the protein expression of P-gp. The protein and mRNA expressions of Bax and Caspase-3 in groups D and E were increased significantly compared with groups A, B and C (group D or E vs group A, B or C, P 〈 0.05). The tumor volume of K562-n was markedly lower in groups C, D and E than in groups A and B (group C, D or E vs group A or B, P 〈 0.05). Conclusion: In conclusion, DNR loaded Fe3O4-magnetic nanoparticles can suppress the growth and induce apoptosis further on the MDR K562-n/VCR tumor in vivo compared to DNR alone but not on the K562-n tumor. The external magnetic field failed to improve the antitumor effect.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    Publication Date: 2016-12-02
    Description: While tissue factor (TF)-mediated blood coagulation is essential for maintaining hemostasis, the aberrant activation of TF-mediated coagulation is a major determinant of thrombotic occlusions, the precipitating event in acute myocardial infarction, unstable angina, and ischemic stroke. Typically, TF on cell surfaces exists in inactive coagulant status (cryptic TF). Cell injury leads conversion of cryptic TF to coagulant active/prothrombotic TF. Molecular differences between cryptic and procoagulant TF and the mechanisms that are responsible for the conversion from one to the other form are poorly understood and often controversial. A majority of the evidence in the literature suggest that level of anionic phospholipids, such as phosphatidylserine (PS), in the outer leaflet of the plasma membrane plays a critical role in regulating TF procoagulant activity at the cell surface. However, other pathways, such as the thioredoxin system or thiol-disulfide exchange pathways involving protein-disulfide isomerase (PDI), were also shown to contribute to TF activation by inducing structural changes in TF. It is unknown at present whether TF on cell surfaces of naïve cells exists primarily in the cryptic state because of the limited availability of anionic phospholipids at the outer leaflet or phospholipids present in the outer leaflet play an active role in maintaining TF in the cryptic state. In the outer leaflet of mammalian plasma membrane, sphingomyelin (SM) constitutes up to 50% of the total phospholipids present on the cell surface. It is possible that a high SM content in the outer leaflet may be responsible for maintaining TF in its cryptic state at the cell surface in naïve cells, and the hydrolysis of SM on the outer leaflet mediated by factors released in cell injury contributes to TF activation. The present study was carried out to investigate this possibility. First, we tested the potential effect of SM on TF activity in a reconstituted system in which full-length TF was reconstituted into phospholipid vesicles composed of varying molar concentrations of SM with the remainder of the vesicle consisting of phosphatidylcholine (PC). SM, at 35 mol % or higher concentration in the proteoliposome, inhibited TF coagulant activity significantly as measured in factor X activation assay. Ceramide, having a similar sphingosine backbone as of SM, had no inhibitory effect on TF-FVIIa activation of FX. Measurement of FVIIa-TF amidolytic activity showed that SM does not inhibit the amidolytic activity of FVIIa-TF, indicating that SM neither affects FVIIa binding to TF nor TF-FVIIa cleavage of the small substrate peptide. SM also inhibited significantly TF activity of TF reconstituted in PC/PS (94%:6% mol/mol) vesicles. Next, human monocyte-derived macrophages (MDMs) were treated with varying concentrations of bacterial sphingomyelinase (b-SMase) to hydrolyze SM in the outer leaflet. b-SMase treatment increased cell surface TF activity in a dose-dependent manner. SMase treatment also enhanced the release of TF-bearing microparticles (MPs). SMase treatment had no significant effect on cell surface prothrombinase activity or annexin V binding to MDMs, indicating that b-SMase treatment did not increase PS availability at the cell surface under our experimental conditions. Similar to that observed in bone marrow-derived mouse macrophages, ATP (200 µM) stimulation of MDMs increased cell surface TF activity by about 3-fold and triggered the release of TF+ MPs. Immunofluorescence confocal microscopy revealed that ATP stimulation induced in the translocation of acid(a)-SMase from intracellular compartments to the outer leaflet of the plasma membrane. Treatment of MDMs with sphingomyelinase inhibitors, desipramine and imipramine (1 and 5 µM), or silencing a-SMase with siRNA markedly reduced the ATP-induced increased TF activity at the cell surface and TF+ MPs release. Finally, ATP stimulation was shown to increase the hydrolysis of SM in the outer leaflet of MDMs markedly. a-SMase inhibitors or silencing of a-SMase attenuated the ATP-induced SM hydrolysis. In summary, our data indicate that SM plays a critical role in maintaining TF in the cryptic state in resting cells. Activation/translocation of a-SMase to the outer leaflet following the activation of ATP receptor P2X7 leads to hydrolysis of SM and thus relieves the inhibitory effect of SM on TF, leading to TF decryption and the release of TF+ MPs. Disclosures No relevant conflicts of interest to declare.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Publication Date: 2019-08-15
    Description: Tissue factor (TF) is a cofactor for factor VIIa and the primary cellular initiator of coagulation. Typically, most TF on cell surfaces exists in a cryptic coagulant-inactive state but are transformed to a procoagulant form (decryption) following cell activation. Our recent studies in cell model systems showed that sphingomyelin (SM) in the outer leaflet of the plasma membrane is responsible for maintaining TF in an encrypted state in resting cells, and the hydrolysis of SM leads to decryption of TF. The present study was carried out to investigate the relevance of this novel mechanism in the regulation of TF procoagulant activity in pathophysiology. As observed in cell systems, administration of adenosine triphosphate (ATP) to mice enhanced lipopolysaccharide (LPS)-induced TF procoagulant activity in monocytes. Treatment of mice with pharmacological inhibitors of acid sphingomyelinase (ASMase), desipramine and imipramine, attenuated ATP-induced TF decryption. Interestingly, ASMase inhibitors also blocked LPS-induced TF procoagulant activity without affecting the LPS-induced de novo synthesis of TF protein. Additional studies showed that LPS induced translocation of ASMase to the outer leaflet of the plasma membrane and reduced SM levels in monocytes. Studies using human monocyte-derived macrophages and endothelial cells further confirmed the role of ASMase in LPS- and cytokine-induced TF procoagulant activity. Overall, our data indicate that LPS- or cytokine-induced TF procoagulant activity requires the decryption of newly synthesized TF protein by ASMase-mediated hydrolysis of SM. The observation that ASMase inhibitors attenuate TF-induced coagulation raises the possibility of their therapeutic use in treating thrombotic disorders associated with aberrant expression of TF.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    Publication Date: 2018-11-29
    Description: Introduction CRISPR/Cas9 system is a highly efficient genomic editing system. However, application of CRISPR/Cas9 system in vivo is somewhat limited for delivery methods and safety concerns. Extracellular vesicles (EVs) are released by exocytosis which results in consistent surface membrane proteins with original cells and capable to deliver several kinds of materials in vivo. However, EVs can be absorbed by other organs or tissues besides tumors, leading to possible off-target effects. Therefore, it is imperative to enhance the targeting property of EVs in vivo. Recently, clinical advances have confirmed that CAR-T cells possess great tropism and multiple choices of target. This may be an effective means to improve EVs' selective accumulation in tumors. In this proof-of-principle study, we exploit the target precision of CAR to establish an EV-derived tropism-delivery platform for CRISPR/Cas9 system as a novel therapeutic strategy for malignant diseases. Methods We established CD19-CAR-293T cell line by CAR lentivirus transfection. Raji cells (Burkitt lymphoma) were chosen as target tumor cells for it's CD19 positive. For the isolation of EVs from CD19-CAR-293T and 293T cells, culture medium was harvested, centrifuged and filtered through 0.45μm filters to remove the dead cells and large microvesicles. Purified EVs were examined by (NTA). The plasmids of CRISPR/Cas9 system targeting human cMyc gene were constructed by standard protocols and electroporated into EVs using Gene Pulser Xcell Electroporation System (BioRad). EVs were labelled with lipophilic fluorescent dye for visualization of confocal images. Uptake of EVs in Raji cells was analyzed using confocal microscope. To observe the biodistribution of EVs, Raji-bearing xenograft NOD/SCID mice were generated. When the tumors reached 200mm3, labelled EVs were intracardially injected to mice. Biofluorescence images were obtained using IVIS imaging system. Results NTA showed that a size distribution of approximately 100nm to 450nm for two types of EVs (Fig. 1A). The modifications didn't affect the physical properties. We used a fixed number ratio of Raji cells to EVs in incubation to compare the uptake efficiency between normal EVs and CD19-CAR-EVs. After one hour of incubation with Raji cells, uptake efficiency of the CD19-CAR-EVs was higher than that of the normal EVs, as indicated by signal intensity in the confocal microscope images (Fig. 1B). To confirm whether CD19-CAR-EVs could target tumors in vivo, we intracardially injected the same number of labelled EVs or CD19-CAR-EVs to Raji xenograft NOD/SCID mice and observed at 0h and 24h post-injection. As results, the CD19-CAR-EVs significantly accumulated in tumor sites compared to liver, kidney and other tissues. In contrast, the normal EVs were distributed throughout the body (Fig. 1C). Ex vivo images exhibited that compared with the EV group, the CD19-CAR-EVs accumulated more in tumors and less in liver, kidney and other tissues (Fig. 1C). The tumor/whole-body fluorescence intensity ratios were calculated in the EV and CD19-CAR-EV groups (Fig. 1D). At 24h post-injected, the ratios in the CD19-CAR-EV group were higher than that in EV group (P
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    Publication Date: 2019-11-13
    Description: The first two authors contributed equally. Introduction: VenR (2 years of Ven, plus R during the first 6 months) improved progression-free/overall survival (PFS/OS) vs bendamustine + R (BR) in patients (pts) in with R/R CLL in MURANO (Seymour et al. N Eng J Med 2018). MURANO also showed early, sustained and durable undetectable minimal residual disease (uMRD) status with VenR, which is associated with prolonged survival in CLL (Kater et al. J Clin Oncol 2019). Here we explore associations between baseline molecular characteristics and VenR-induced MRD responses and PFS based on the 4-year follow-up of MURANO. Methods: DNA specimens from CD19-enriched baseline samples (313/389 enrolled pts) were analyzed with whole-exome sequencing (WES). Genetic complexity (GC) was assessed by array comparative-genomic hybridization. Gene expression data were generated by RNA sequencing from matched RNA samples (209 pts). Univariate analysis determined the impact of gene mutations, GC, and BCL-2 (family) expression on MRD and PFS at end of combination therapy (EOCT) and end of treatment (EOT). MRD (peripheral blood only) was categorized as uMRD
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    Publication Date: 2007-11-16
    Description: Objective: The present study aimed to evaluate the MDR reversal activity of bromotetrandrine (BrTet), a bromized derivative of tetrandrine (Tet), in vitro. Methods: Drug sensitivity was determined using the MTT assay. Adriamycin (ADM) accumulation, the protein levels of P-glycoprotein (P-gp) and the apoptotic changes were analyzed by fluorospectrophotometry, respectively. The mRNA levels of P-gp was determined by RT-PCR. Results: BrTet at 0.25, 0.5 and reversed ADM resistance in MDR K562/A02 cells dose-dependently and its potency was greater than that of Tet at the same concentrations. The IC50 of ADM for K562 and K562/A02 cells were 55.122 mg/l and 1.1373 mg/l, respectively. Treating K562/A02 cells with BrTet(1uM)and TTD(1uM)both for 48 hours partially restored the sensitivity of K562/A02 cells to ADM (IC50 were 4.7729 mg/l and 13.584 mg/l respectively) but had not effect on K562 cells. The fold reversal (FR) were 11.55 and 4.06 respectively. K562/A02 cells showed apoptotic characteristics after treated with Brtet and Tet both for 48 hours compared with control group(apoptosis rate was 61.1%, 11.1% and 9.9%,respectively); Fluorospectrophotometric assay showed that BrTet significantly increased the intracellular accumulation of ADM in K562/A02 cells in a dose-dependent manner. The fluorescence intensity of intracellelar ADM in K562/A02 cells treated with ADM(1mg/L)was 33% of that in K562 cells. BrTet and Tet elevated the intracellular ADM concentration in K562/A02 cells up to 52% and 69%,respectively. BrTet also inhibited the overexpression of P-gp in K562/A02 cells. The fluorescence intensity of P-gp in K562 and K562/A02 cells was 0.5 and 97.97.The P-gp expression was down after treated with BrTet and TTD (65.05 and 54.86). The mdr1 mRNA was also down regulated. Conclusions: BrTet showed significant MDR reversal activity in vitro. Its activity may be related to the inhibition of P-gp overexpression and the increase in intracellular accumulation of anticancer drugs. BrTet may be a promising MDR modulator for eventual assessment in the clinic.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Publication Date: 2008-11-16
    Description: Objective This study was to compare the reversal effect of 5-bromotetrandrine (BrTet) with Tetrandrine (Tet) when combined with ADM on multidrug resistance cell line K562/A02 and to investigate the reversal mechanism of this new derivative. Methods The protein levels of P-glycoprotein (P-gp) were detected by fluorospectrophotometry and Western blot. The mRNA levels of P-gp were determined by RT-PCR. The in vivo effect of Tet was investigated using nude mice grafted with sensitive human leukemia cell line K562 and MDR cell line K562/A02. Results Flow cytometry assay showed that 1.0 μMol/L BrTet significantly increased the apoptosis percentage. BrTet also enhanced the intracellular accumulation of ADM in K562/A02 cells and its potency was greater than that of Tet at the same concentrations. BrTet inhibited the overexpression of P-gp and down regulated MDR1 mRNA expression in K562/A02 cells in a dose-dependent manner. In nude mice bearing K562 xenografts on the left flank and K562/A02 xenografts on the right flank, i.p. injection of 10 mg/kg BrTet significantly enhanced the antitumor activity of ADM against K562/A02 xenografts with inhibitory rates of 26.1%, while ADM alone inhibited the growth of KBv200 xenografts by only 5.8%. Conclusion BrTet showed significant MDR reversal activity in vitro and in vivo. Its activity may be related to the inhibition of P-gp overexpression and the increase in intracellular accumulation of anticancer drugs, which lead to more K562/A02 cells apoptosis.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    Publication Date: 2008-11-16
    Description: Objective: The changes of methylation of CpG Island are the frequent changes in epigenetic. Nowadays, there are many methods to detect the changes of methylation, but all these method are hard to quantitate precisely. In our experiment, we will establish a new precise method. Methods: Use hydrosulfite to handle the DNA, and then do PCR. The cytosine will change to thymine, if it hasn’t been methylation. On the other side, the cytosine will maintain its state if it has been methylation. Design a pair of probe, which contain one methylation probe and one un methylation probe. This pair of probe will detect three consecutive sites of CpG island in P16. Our experiment will use gene chip. Mix the the DNA of methylation and unmethylation with different ratio, then build the standard curve. Contrast the patient sample with standard curve will get the quantitate result. Results: We detected three patients, the methylation degree of the patients is 84.3%, 0%, 17.7%. Conclusion: The method we used can detect methylation degree of three consecutive sites of P16 quantitate precisely. Solve the problem of quantitate precisely.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    Publication Date: 2019-11-13
    Description: Introduction: Venetoclax (Ven) is a highly selective oral inhibitor of key apoptosis regulator BCL-2, which is overexpressed in CLL. MURANO (a randomized Phase III study) compared fixed-duration VenR with standard bendamustine-rituximab (BR) in R/R CLL. The superior progression-free survival (PFS) of VenR versus BR was established in the first pre-planned analysis (Seymour et al. N Engl J Med 2018); continued PFS benefit was seen with longer follow-up and after all patients (pts) had completed therapy (Kater et al. J Clin Oncol 2019). We now present data from a further analysis (median follow-up 48 months) when all pts had been off Ven treatment for median 22 months. Methods: As previously published, pts were randomized to 6 cycles of VenR then Ven 400mg once daily for 2 years in total, or 6 cycles of BR. PFS status was based on investigator assessment. Central analysis of minimal residual disease (MRD) status in peripheral blood (PB) was performed at Cycle 4, end of combination treatment (EOCT) then every 3-6 months. Pts were categorized as undetectable MRD (uMRD;
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    Publication Date: 2016-12-02
    Description: Introduction: The anti-apoptotic protein BCL2 is overexpressed in a number of hematological malignancies, including chronic lymphocytic leukemia (CLL). Venetoclax (VEN) is a selective, oral BCL2 inhibitor with demonstrated activity and an acceptable safety profile both as monotherapy and in combination regimens in relapsed/refractory (R/R) CLL patients (pts). VEN has demonstrated preclinical activity with bendamustine/rituximab (BR), a standard treatment in this population, as well as clinical efficacy with R. The anti-CD20 mAb obinutuzumab (G) has demonstrated improved efficacy in combination with chlorambucil compared with R. Here we present an interim analysis of an ongoing phase 1b study (GO28440) evaluating the maximum tolerated dose (MTD) of both VEN+BR and VEN+BG, plus safety, tolerability, efficacy and optimal order of administration in both R/R or 1L CLL pts (NCT01671904). Methods: Pts with ECOG PS ≤1, 0-3 prior chemotherapy lines, and adequate marrow, hepatic, renal and coagulation function are being enrolled in dose finding cohorts (VEN 100-400mg/day +BR or +BG in a 3+3 dose escalation design) and subsequent safety expansion cohorts (400mg). Dose finding occurs in one of two dosing schedules: Schedule A (VEN introduced before BR or BG) or Schedule B (BR or BG introduced before VEN), with one chosen for expansion per unique population/drug grouping. Both schedules include a gradual VEN dose ramp-up and other prophylactic measures based on risk stratification to reduce the risk of tumor lysis syndrome (TLS). Following completion of 6 months of combination therapy, pts continue single-agent VEN until unacceptable toxicity, disease progression, or (for 1L pts only) up to 1 year total VEN. Dose-limiting toxicity (DLT) data are reviewed after all pts in a cohort have completed 21 days of combination treatment at the target VEN dose and focus on TLS and cytopenias. Efficacy is assessed by iwCLL guidelines; Hallek et al. 2008. Results: At data cutoff (May 2, 2016), 55 pts (baseline characteristics and disposition in Table 1) have been treated; 47 pts received VEN+BR: 30 R/R (12 on Schedule A at doses 100-400mg, 18 on Schedule B all at 400mg) and 17 1L (all at 400mg: 6 on Schedule A, 11 on Schedule B). Eight pts received VEN+BG: all on Schedule B at 400mg. Safety is summarized for VEN+BR (R/R and 1L) and VEN+BG (1L) in Table 2. The most common AEs across all groups were neutropenia, thrombocytopenia, and nausea. Most G3-4 AEs across all groups were hematological toxicities; common non-hematological AEs included diarrhea and fatigue. Platelet transfusions occurred in 4 (13%) R/R VEN+BR and 1 (13%) 1L VEN+BG pts. There were serious AEs in 21 pts (43% R/R VEN+BR, 35% 1L VEN+BR, 25% 1L VEN+BG) including febrile neutropenia, nausea, vomiting, erythema, and infection. No deaths were reported. No TLS events (laboratory or clinical) were observed. Dose interruptions or modifications for VEN and/or BR/BG occurred in 35 (75%) of VEN+BR pts (22 R/R, 13 1L) and 7 (88%) VEN+BG pts, mainly due to neutropenia. Early VEN discontinuations for toxicity: 7 pts VEN+BR (R/R), 2 pts VEN+BR (1L), 1 pt VEN+BG. Early B and/or R/G discontinuations for toxicity: 10 pts VEN+BR (R/R), 4 pts VEN+BR (1L), 2 pts VEN+BG. Common reasons for discontinuations (≥1 pt) included neutropenia and thrombocytopenia. Across all pts, a median of 4 cycles of B were completed. Best overall response and minimal residual disease (MRD) status for evaluated pts are presented in Table 3. All but one R/R pt (off study early for disease transformation) responded across all groups. Conclusion: This study is the first to evaluate both VEN+BR and VEN+BG in pts with CLL. VEN 400mg daily can be combined with BR or BG in patients with either R/R or 1L CLL; neutropenia and thrombocytopenia are manageable with an otherwise acceptable safety profile. Administration schedules (VEN or BR first) appear to have similar toxicity profiles, with no DLT or lab/clinical TLS reported for either during dose finding. As expected, due to the known safety profile of VEN and B, hematologic toxicity was observed with VEN+BR; early VEN+BG safety data appears similar. Events appeared manageable, although early discontinuations contributed to a median of 4 completed cycles of B across all pts. Even with median of
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    Publication Date: 2017-12-07
    Description: Introduction: Effective treatment options for patients (pts) with R/R AML are limited and novel therapies are needed. Previous pre-clinical data have shown that venetoclax (VEN) plus cobimetinib (cobi) or idasanutlin (idasa) may be synergistic. MEK and MDM2 inhibition have been shown to down-regulate MCL-1, overcoming a resistance pathway to BCL-2 inhibition in AML (Han, ASH 2016; Pan, ASH 2014). We report preliminary results from a dose-escalation study evaluating VEN plus cobi or idasa in pts with R/R AML. This is the first study evaluating novel-novel oral combinations with VEN in pts with AML. Methods: This open-label, multicenter study evaluates the safety, tolerability and efficacy of VEN + cobi or idasa in pts ≥60 yrs old with R/R or secondary AML who have received therapy for a prior antecedent hematological disease and are not eligible for cytotoxic therapy (NCT02670044). Two-dimensional dose escalation is being used to establish the maximum tolerated dose (MTD) for each combination. Pts on Arm A received VEN PO daily + cobi PO on Days 1-21, and pts on Arm B received VEN PO daily + idasa PO on Days 1-5 in 28-day cycles. Dose limiting toxicities (DLTs) were assessed for the first cycle. Results: As of 25 April 2017, 42 pts were treated in the dose-escalation stage. Arm A included 4 cohorts: VEN 400 mg + cobi 40 mg (n=4), VEN 600 mg + cobi 40 mg (n=7), VEN 800 mg + cobi 40 mg (n=4) and VEN 400 mg + cobi 60 mg (n=7); Arm B included 3 cohorts: VEN 400 mg + idasa 200 mg (n=3), VEN 600 mg + idasa 200 mg (n=8) and VEN 400 mg + idasa 400 mg (n=9). Median age was 72 (range 60-93) yrs and median number of prior therapies was 2 (range 1-10). 19% (8/42) were ECOG 2, 62% (26/42) of pts were refractory to last therapy and 48% (20/42) of pts had secondary AML. According to ELN risk classification, 29% were intermediate-I, 34% intermediate-II and 34% were adverse risk. Most common AEs in both arms are summarized in Table 1. In the VEN + cobi arm, the majority of deaths on study were due to progressive disease (PD); 3 deaths were due to AEs of sepsis, pneumonia and respiratory failure. Three DLTs were reported: 1 diarrhea (Gr 3) in VEN 600 mg + cobi 40 mg and 1 diarrhea (Gr 3) and 1 decrease in ejection fraction (EF) (Gr 3) in VEN 400 mg + cobi 60 mg. The Gr 3 decrease in EF occurred in the setting of sepsis and was subsequently not considered related to study treatment. Due to the higher rates of Gr ≥3 diarrhea (57%) in VEN 400 mg + cobi 60 mg, this dose level will no longer be evaluated in this study. The VEN 800 mg + cobi 40 mg cohort is ongoing. In the VEN + idasa arm, the most common cause of death was PD; 1 death was due to an AE of sepsis. Four DLTs were reported: 1 generalized muscle weakness (Gr 3) and 1 diarrhea (Gr 3) in VEN 600 + idasa 200 mg and 1 acute coronary syndrome (Gr 3) and 1 elevated bilirubin (Gr 4) in VEN 400 mg + idasa 400 mg. Additional dose cohorts evaluating VEN + idasa are ongoing. When compared to monotherapy data at the same dose, preliminary PK analyses suggest that VEN exposure is slightly lower, while cobi and idasa exposures are similar. Preliminary efficacy for the VEN + cobi arm showed 2 CRs (9%), 1 CRp (4.5%) and 1 CRi (4.5%) for an overall response rate (ORR) of 18% (4/22); duration of response (DOR) ranged from 1 to 5 mo, with 1 response ongoing at data cut-off. For the VEN + idasa arm, 1 CR (5%), 1 CRp (5%), 1 CRi (5%) and 1 PR (5%) were achieved for an ORR of 20% (4/20); DOR ranged from 1.3 to 6.7 mo, with 1 response ongoing at data cut-off. In the VEN 600 mg + idasa 200 mg cohort, the ORR was 38% (3/8) with 1 CR, 1 CRp, and 1 CRi. Of the pts who did not achieve a response by IWG criteria, anti-leukemic activity was seen in an additional 7 pts who achieved ≥ 50% bone marrow blast reduction from baseline (3/22 [14%] pts on VEN + cobi and 4/20 [20%] pts on VEN + idasa). Baseline mutation profiling was available in 32 of 42 pts and is summarized for responders in Table 2. Of the 9 pts who had an IDH1/2 mutation at baseline, 44% (4/9) achieved a response (1 on VEN + cobi and 3 on VEN + idasa). Of the 3 pts with known p53 mutations on the VEN + idasa cohorts, none achieved a response. Conclusions: Preliminary results show that VEN plus cobi or idasa can be administered with appropriate risk mitigation measures for GI toxicity and early evidence of clinical activity in R/R AML pts. Dose finding is ongoing and the MTD for both combinations has not yet been determined. Preliminary ORR for the VEN 600 mg + idasa 200 mg cohort was encouraging at 38%. Safety, PK and efficacy data will be updated at the time of presentation. Disclosures Daver: Novartis Pharmaceuticals Corporation: Consultancy; Pfizer Inc.: Consultancy, Research Funding; Otsuka America Pharmaceutical, Inc.: Consultancy; Karyopharm: Consultancy, Research Funding; Incyte Corporation: Honoraria, Research Funding; Bristol-Myers Squibb Company: Consultancy, Research Funding; Daiichi-Sankyo: Research Funding; Jazz: Consultancy; Immunogen: Research Funding; Kiromic: Research Funding; Sunesis Pharmaceuticals, Inc.: Consultancy, Research Funding. Pollyea: Takeda, Ariad, Alexion, Celgene, Pfizer, Pharmacyclics, Gilead, Jazz, Servier, Curis: Membership on an entity's Board of Directors or advisory committees; Agios, Pfizer: Research Funding. Yee: Oncoethix: Research Funding; Novartis Canada: Honoraria; Astex: Research Funding; Karyopharm: Research Funding; Celgene Canada: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Fenaux: Janssen: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Amgen: Honoraria, Research Funding; Amgen: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Astex: Honoraria, Research Funding; Astex: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Celgene: Honoraria, Research Funding. Kelly: Abbvie: Honoraria; Pharmacyclics: Honoraria; Amgen: Honoraria; Jannsen: Honoraria. Roboz: Cellectis: Research Funding; AbbVie, Agios, Amgen, Amphivena, Array Biopharma Inc., Astex, AstraZeneca, Celator, Celgene, Clovis Oncology, CTI BioPharma, Genoptix, Immune Pharmaceuticals, Janssen Pharmaceuticals, Juno, MedImmune, MEI Pharma, Novartis, Onconova, Pfizer, Roche Pharmace: Consultancy. Kshirsagar: Genentech, Inc: Other: Services via contractor. Dail: Genentech, Inc.: Employment. Wang: Genentech: Employment. Mobasher: Roche: Equity Ownership; Genentech: Employment. Chen: 4. F. Hoffmann-La Roche Ltd: Employment, Equity Ownership. Hong: Genentech: Employment; F. Hoffmann-La Roche Ltd: Equity Ownership.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...