ALBERT

Description: Abstract 1877 Secondary myelodysplastic syndrome and acute myelogenous leukemia (2° MDS/AML) are well-known complications that can occur after alkylating agent therapy for multiple myeloma (MM) or other cancers. However, until recently, the survival of MM pts was relatively short, a feature which may have contributed to a relatively low reported incidence of this complication in MM. The introduction of novel agents has improved survival rates of MM pts; lenalidomide (len) + dexamethasone–currently approved for MM after one prior therapy– is one of the main regimens that has contributed to this finding. Since alkylating agents—either given orally or as part of high-dose melphalan + ASCT—still remain an important component of myeloma therapy, more pts may survive to be at risk for 2° MDS/AML. Using the MM database at PMH, we retrospectively reviewed the charts of pts with relapsed/refractory (rel/ref) MM treated with len-based regimens to determine the incidence and characteristics of 2° MDS/AML that developed during this therapy. Between 06/2006—11/2009, 230 pts with rel/ref MM received ≥ 1 cycle of len + corticosteroids (195 pts), len alone (3 pts) or cyclophosphamide + len + prednisone (CPR) (32 pts). 2° MDS/AML developed in 6 (2.6%) at a median of 76 months (range 43–190) from the time of diagnosis of MM and 61 (21-168) months from the time of initiation of len regimens. The cytogenetic changes were variable, but 4 pts had deletions of all or part of chromosome 5. The characteristics of pts, at the time of starting len, in those who later developed (+) or did not develop (-) 2° MDS/AML during therapy, are shown in Table 1. The median number of len cycles given was 21 (9-35) versus 9 (1-50) and Grade 3–4 neutropenia occurred during len in 50% versus 54% in those with and without 2° MDS/AML, respectively. G-CSF was used in 50% of pts who developed MDS compared with 54% who did not. The cumulative incidence of 2° MDS/AML (95% CI) was 1% (0-5 %) at 1 yr, 3% (1-9 %) at 8 yrs and 7% (2-19 %) at 12 yrs from the time of diagnosis of MM, while the cumulative incidence was 1% (0-5 %) at 1 yr, 4% (1-9 %) at 2 yr and 9% (4-12%) at 3 yrs after commencing len-based regimens. We conclude: 1) pts developing MDS/AML while on len regimens were slightly older and had less often received prior ASCT, thalidomide and bortezomib; 2) the pattern of MDS development is consistent with the hypothesis that extensive exposure to cytotoxic agents, particularly oral alkylating agents (which had been given to 5/6 [83%] of affected pts), increases the risk of 2° MDS/AML; 3) although len is effective therapy in some pts with MDS, its use does not protect heavily pre-treated MM pts from this complication. Disclosures: Reece: Celgene: Honoraria, Research Funding. Off Label Use: Combination of lenalidomide and cylophosphamide plus prednisone in relapsed and refractory myeloma patients. Chen:Celgene Corporation: Consultancy, Honoraria, Research Funding. Kukreti:Celgene: Honoraria. Trudel:Celgene: Honoraria.

Description: Mantle cell lymphoma (MCL) accounts for 3–10% of all lymphomas and demonstrates a poor clinical response to current therapeutic approaches, with a median survival of 3–5 years. The natural history of MCL is heterogeneous and not well-defined by standard clinical markers as patients may die within months of diagnosis or experience long-term survival. There remains a need for reliable biomarkers of MCL prognosis. To date, global gene expression signatures have not been determined for formalin-fixed, paraffin-embedded (FFPE) MCL samples due to difficulties isolating full-length mRNA transcripts from FFPE tissues. Examining microRNA expression in FFPE samples may circumvent this problem, as this population of RNAs remains intact during processing of FFPE samples. MicroRNAs (miRs) are small, non-coding RNAs, which regulate gene expression by inhibiting mRNA translation. Although miR expression signatures have been derived for other hematological malignancies, assessment of miR expression in patients with MCL has yet to be undertaken. We hypothesize that different pathological subtypes of MCL have unique miR expression signatures, distinct from miR expression profiles of other B-cell non-Hodgkin lymphomas. Our objectives were two-fold: To determine and validate miR expression in different pathological subtypes of MCL; and, To compare miR expression in MCL to other B-cell non-Hodgkin lymphomas. Total RNA was extracted from FFPE samples [17 conventional MCL, 11 blastoid MCL, 4 follicular lymphomas (Grades 1, 2, 3a, and 3b), 1 nodal marginal zone lymphoma, 1 small lymphocytic lymphoma (SLL/CLL) and 3 benign, reactive lymph nodes (normal controls)] using the RecoverAll kit for FFPE tissues (Ambion). RNA was subjected to quantitative real-time PCR (qRT-PCR) for 365 miRs and 3 endogenous control small nucleolar RNAs to obtain miR expression profiles using the TaqMan Low Density Array (TLDA) v1.0 platform (MicroFluidic card, Applied Biosystems). TLDAs were run on the ABI7900 HT analyzer with TLDA upgrade and analysed with RQ Manager software provided by Applied Biosystems. Expression profiles were correlated to pathological subtype, and hierarchical clustering, principal component analysis (PCA), and ANOVA were performed using Partek software [Partek Genomics Suite for Gene Expression Data]. Results indicate that miR expression profiles differ between B-cell, non-Hodgkin lymphoma and MCL samples. Clustering analysis and PCA both demonstrated different profiles between MCL and B-cell, non-Hodgkin lymphomas. Although PCA did not demonstrate significant differences between the conventional and blastoid MCL samples, a set of fifteen miRs may be able to distinguish these two groups of MCL, since these 15 miRs are relatively upregulated in blastoid MCL in comparison to conventional MCL. In addition, PCA revealed five (3 conventional MCL samples and 2 blastoid samples), which did not cluster with their respective groups. These five samples were from patients known to have progressive disease, indicating that such patients may have different miR expression profiles compared to patients with non-progressive disease. We conclude that high-throughput miR expression profiles can be generated from FFPE samples in B-cell non-Hodgkin lymphomas and that miR expression profiles for MCL samples differ from those of other B-cell non-Hodgkin lymphomas. Blastoid and conventional MCL samples may not have significantly differing profiles, however a set of 15 miRs appears to be able to distinguish between these two groups. Of note, samples from patients with known progressive disease have significantly different profiles from those with non-progressive disease.

Description: Abstract 1876 Multiple myeloma (MM) is a neoplastic process involving plasma cells and the second most common hematologic malignancy after lymphoma. The relative survival rates for MM have been increasing over the last three decades, from 26% in the 1970s to 35% in recent years, due to the introduction of autologous stem cell transplantation (ASCT), and more recently, the introduction of novel agents. Among patients (pts) diagnosed with MM between 1997 and 2006, those who received at least one of the novel agents thalidomide, lenalidomide and bortezomib had double the median survival compared to those who did not receive any of these treatments (Kumar SK, Blood, 2008). Given that improvements are being made in the survival of myeloma pts, they may be more prone treatment-related complications, including treatment-related myelodysplastic syndrome (MDS) or acute myelogenous leukemia (AML). Herein we report seven cases of secondary MDS occurring in MM pts during treatment with lenalidomide-based (len-based) therapy for relapsed/refractory (rel/ref) MM. The pts examined were diagnosed with MM between 2000 and 2006, and consisted of 5 males and 2 females, ranging from 56–79 years of age (median age: 69 years). Five of the seven pts had undergone ASCT whereas the remaining two pts were treated with oral alkylating agents (cyclophosphamide/prednisone or melphalan/dexamethasone) as first-line treatment; one pt received another ASCT as second-line therapy. All pts received len-based regimens as second, third, or fourth-line therapy. The median time to development of MDS after diagnosis of MM was 70.5 months (range: 43.7 to 115.3 months). Of the pts that received ASCT as part of first-line therapy, the median time to development of MDS was 49.9 months (range: 35.6 to 76.1 months) post ASCT, while the median time to development of MDS after initiation of len-based treatment was 19.2 months (range: 1.1 to 33.8 months). All pts presented with decreasing blood counts at the time of MDS diagnosis; at this time the median hemoglobin level was 94 g/L (range 67–107 g/L), ANC 1.7 × 109/L (range 0.9–8.2 × 109/L) and platelet count 62 × 109/L (range 11–148 × 109/L) and only 1 pt had circulating blast cells. Pathological examination of blood films, bone marrow aspirates and biopsies confirmed the presence of MDS in all pts (4 pts with refractory cytopenia with multilineage dysplasia, 2 of whom also had ringed sideroblasts, 2 pts with refractory cytopenia with unilineage dysplasia, and 1 pt with refractory anemia with excess blasts-II); three had concomitant MM in the marrow. Of interest, 3 pts with evidence of dysmegakaryopoiesis demonstrated the presence of hypolobated megakaryocytes, similar to that seen in 5q- syndrome. Conventional cytogenetics demonstrated complex karyotypes in 6 pts, and 4 had structural abnormalities of chromosome 5, with deletion of the long arm, including 2 of the 3 pts with megakaryocyte hypolobation. Four of the 7 pts also had abnormalities involving chromosome 7, including deletion of 7q. In addition, 2 pts had deletions of chromosome 17 including deletion of TP53 (17q13). Although len may be a simple bystander in the development of MDS in rel/ref MM pts previously treated with alkylating agents, the observation of chromosome 5 abnormalities, including 5q deletion, is of note. Therefore, despite its established efficacy in the treatment of MDS, as well as of MM, len may not be able to protect against the development of MDS in pts previously treated with alkylating agents. As in other malignancies in which prolonged survival has been achieved, the increased life span of MM pts mandates monitoring for late complications of therapy. A progressive decrease in peripheral blood counts during treatment with len-based regimens warrants consideration of secondary MDS. Disclosures: Chen: Celgene Corporation: Consultancy, Honoraria, Research Funding. Trudel:Celgene: Honoraria. Reece:Celgene: Honoraria, Research Funding.

Description: Abstract 1586 Background Mantle cell lymphoma (MCL) is a subtype of B-cell non-Hodgkin lymphoma (NHL) characterized by the t(11;14) translocation and concomitant over-expression of cyclin D1. MCL has a variable natural history; while some patients have prolonged survival similar to other indolent B-cell lymphomas, most follow an aggressive course with short survival. While the t(11;14) is pathognomonic of MCL, it is not necessary for disease pathogenesis, as a subset of MCL cases lack the translocation. Furthermore, in vivo models demonstrate that cyclin D1 over-expression alone is unable to bring about the disease, and that deregulation of additional cellular pathways is required for its pathogenesis. Assessment of microRNA (miR) expression in MCL may help determine mechanisms of gene deregulation and reveal pathways involved in disease pathogenesis. In this study we examined MCL in relation to both aggressive and indolent B-cell NHL to determine a miR signature that characterizes MCL. Design and Methods Total RNA from a training set of 36 B-cell NHL cases (19 indolent and 17 aggressive) and 32 MCL was applied to a high-throughput quantitative real-time PCR platform assessing the expression of 365 miRs [TaqMan Human MicroRNA Array v1.0 (Early Access) or TLDA]. miRs that were differentially expressed between MCL and aggressive NHL, and between MCL and indolent NHL were then validated using RNA from a second, independent, set of B-cell NHL cases (28 indolent and 28 aggressive) and 50 MCL cases. Validated miRs were determined and potential targets for each miR were examined. A map of targets common to the MCL miR signature was created, revealing important proteins involved in MCL pathogenesis. Results 66 miRs (11 over-expressed, 55 under-expressed) were differentially expressed between MCL and aggressive B-cell NHL and 8 miRs (7 over-expressed, 1 under-expressed) were differentially expressed between MCL and indolent B-cell NHL (false discovery rate = 0.2). 6 miRs from each group were chosen for validation in an independent set of MCL and NHL cases. Of these 12 miRs, 7 miRs validated (2 were under-expressed in MCL relative to aggressive B-cell NHL, and 5 were over-expressed in MCL relative to indolent B-cell NHL). Genes and pathways involved in disease pathogenesis are most likely targeted by multiple miRs. We thus determined a set of 123 genes predicted to be targets of this MCL miR signature, based on five miR target prediction databases from the mirDIP (microRNA data integration) portal. These genes were significantly enriched for focal adhesion and integrin signalling, proteasome-mediated degradation, and the PI3K signalling pathway. Conclusions Using the largest set of MCL cases evaluated to date, a 7-miR signature characteristic of MCL was discovered. The gene targets of these miRs are enriched for roles in proteasome-mediated protein degradation, consistent with the reported sensitivity of MCL to proteasome inhibitors. In addition, these miRs are predicted to be involved in regulation of PI3K/AKT signalling, confirming reports of the importance of this pathway in MCL pathogenesis. Enrichment of target genes involved in focal adhesion and integrin signalling indicate the importance of MCL-stromal interactions and motivates further study into the role of the tumor microenvironment in MCL pathogenesis. Disclosures: No relevant conflicts of interest to declare.

Description: Background: The LY.12 randomized phase 3 clinical trial defined gemcitabine, dexamethasone and cisplatin (GDP) as an effective outpatient salvage chemotherapy regimen in relapsed/refractory (R/R) patients with aggressive lymphomas who are candidates for autologous stem cell transplant (ASCT) (Crump et al. JCO 2014). When the anti-CD20 antibody rituximab (R) was added to GDP, the ORR was 45.6% by CT imaging and 51.9% of patients were able to receive ASCT. Obinutuzumab (O) is a type 2 CD20 antibody that has demonstrated superiority to R in some studies in indolent lymphomas and is active in R-refractory follicular lymphoma. Improvements in the outcome of salvage therapy have tested alternative CD20 antibodies (Van Imhoff, JCO 2017), to date without success. We report a single centre, single arm clinical trial of O-GDP to assess safety and efficacy in R/R aggressive B cell lymphoma. Methods: Transplant eligible patients with DLBCL and transformed indolent lymphoma were treated with O-GDP for two cycles, followed by response assessment by CT. Non-progressors received a third cycle of O-GDP for stem cell mobilization and a PET/CT scan was obtained after stem cell collection. Responders then proceeded to ASCT per investigator decision. O was given at 1000 mg weekly during the first cycle of GDP and then on day 1 of cycles 2 and 3. Responses were determined by Lugano criteria using investigator assessment. The primary outcome was ORR by CT imaging after 2 cycles. The pre-specified statistical analysis stated that the trial will be declared positive if the ORR was 〉60%, negative if the ORR was 60%. The overall rate of proceeding to ASCT with O-GDP salvage in this trial was 65.5% compared to that previously reported for R-GDP at 51.9%. Disclosures Scott: NanoString: Patents & Royalties: Named Inventor on a patent licensed to NanoString Technologies, Research Funding; Roche: Research Funding; Janssen: Research Funding; Celgene: Consultancy, Honoraria. Kuruvilla:BMS: Consultancy, Honoraria; Abbvie: Consultancy; Leukemia and Lymphoma Society Canada: Research Funding; Seattle Genetics: Consultancy, Honoraria; Amgen: Honoraria; Celgene: Honoraria; Karyopharm: Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Princess Margaret Cancer Foundation: Research Funding; Gilead: Consultancy, Honoraria; Lundbeck: Honoraria; Roche: Consultancy, Honoraria, Research Funding; Merck: Consultancy, Honoraria.

Description: Background: CCTG LY.12 defined GDP (gemcitabine, dexamethasone and cisplatin) (GDP) as an effective outpatient salvage chemotherapy regimen in relapsed/refractory (R/R) patients with aggressive lymphomas who are candidates for autologous stem cell transplant (ASCT) (Crump et al. JCO 2014). Obinutuzumab (O) is an alternative anti-CD20 that may produce responses in rituximab-refractory lymphomas. Head-to-head, O did not improve efficacy compared to R when combined with CHOP as initial therapy (Vitolo JCO 2017). However, salvage therapy differs from initial therapy in that patients have been previously exposed to, and have relapsed after, prior R. We therefore performed a single centre, single arm clinical trial of O-GDP to assess safety and efficacy in R/R aggressive B cell lymphoma as a salvage regimen prior to consolidation with ASCT. Methods: Transplant eligible patients with DLBCL and transformed indolent lymphoma were treated with O-GDP for two cycles, followed by response assessment by CT. Non-progressers received a third cycle of O-GDP for stem cell mobilization and final response assessed by CT-PET prior to ASCT. O was given at 1000 mg weekly during the first cycle of GDP and then on day 1 of cycles 2 and 3. Responses were determined by Lugano criteria using investigator assessment. The primary outcome is ORR by CT imaging after 2 cycles. The pre-specified statistical analysis stated that the trial will be declared positive if the ORR is 〉60%, negative if the ORR is

Description: Background: Post-transplant lymphoproliferative disorder (PTLD) is an uncommon, heterogeneous disease that occurs in the setting of immune suppression following solid organ transplantation. As the transplant population ages over time, the spectrum of PTLD histologies and their treatment has evolved; we report here our recent experience with PTLD from a large multi-organ transplant program. Methods: We identified patients from the Multi-Organ Transplant Program at University Health Network (UHN) who were diagnosed with PTLD between January 1, 2000 and December 31, 2015. We describe the characteristics and outcomes of this cohort, with a focus on the outcome of patients with the diffuse large B cell (DLBCL) subtype of PTLD treated in the rituximab era. Results: A total of 140 patients were diagnosed with PTLD at UHN during this time period (Table 1): 38% were female and median age at time of diagnosis was 50 (interquartile range, IQR Q1/Q3, 37 to 62 years). The most commonly implicated transplants were liver and kidney (33% and 32%), as well as lung (20%) and heart (7%). The median time from organ transplantation to PTLD diagnosis was 61 months (IQR 9 to 136), with 70% of cases occurring more than 12 months following solid organ transplant. Pathologically, the majority of the patients had monomorphic PTLD, with DLBCL (n = 86) being most common. Where classifiable by the Hans algorithm (n = 68), the majority of the DLBCL types were of the non-germinal center B cell type (non-GCB, 76.5%). Of 24 DLBCL patients with available FISH, 7 had a MYC translocation (29%). Treatment and outcome varied by PTLD subtype (Table 2). For the overall cohort (n = 140), the median OS was 5.1 years. Highlighting competing risks, less than half of patients died of PTLD, with the remainder of mortality due to complications of solid organ transplantation, or less commonly, due to treatment-related mortality. Polymorphic PTLD (n = 17) was treated in a variety of ways ranging from reduction in immunosuppression (RIS) alone to R-CHOP; median OS was 10.3 years. Less common histologic subtypes (Hodgkin, Burkitt, T cell) were treated with therapies specific to those lymphomas. For DLBCL (n = 86), treatment consisted of RIS alone (10.5%; OS 4.4 years) or RIS followed by local treatment (involved field radiation or surgical resection) (7.0%; OS not reached); single agent rituximab (R) (22.1%; OS not reached); sequential R followed by CHOP (11.6%; OS 1.5 years), or upfront R-CHOP (43.0%; OS 3.4 years). Median OS for patients classified as non-GCB was not worse than those classified as GCB (OS 6.2 vs. 4.7 years, p = 0.93). In the DLBCL cohort, 20 patients had progression during or after first line therapy, with 14 patients receiving additional treatment. Patients with early relapse during initial therapy or within the first 3 months (n = 13) did poorly compared to patients with later relapse occurring after 3 months (n = 7; median OS 0.7 vs 5.6 years, p 〈 0.01). This was similar to the entire cohort, where 40 patients relapsed and early relapsed/refractory patients also had poor outcomes compared to late relapsing patients (median OS 0.8 vs. 5.1 years, p

Description: Follicular Lymphoma (FL) is the most common indolent lymphoma derived from light zone germinal center B cells and characterized by a t(14;18) translocation resulting in upregulation of BCL2 in over 80% of cases. This translocation alone is not sufficient for tumorogenesis, and must be combined with additional genetic mutations to transform B cells. FL is incurable and the disease course can be highly varied, with survival ranging from a few months to decades following diagnosis and treatment with standard chemoimmunotherapy. The heterogeneity of FL poses major challenges to identifying the association of genetic alterations and clinical outcome. Current WHO guidelines recommend establishing grade for each FL case with grade 3 thought to be more aggressive than 1 and 2. The genetic basis and clinical implications of grade in FL are unclear. Recent sequencing studies have identified many genes found to be recurrently mutated in FL including KMT2D and CREBBP. However, the degree to which genetic alterations cooperate with each other or contribute to clinical outcome is unclear. Based on the observed mutational rates in follicular lymphoma, we estimated 900 cases were needed to comprehensively delineate the genetic alterations that underlie histologic grade and clinical outcome. Accordingly, we enrolled a cohort of 1042 patients with newly diagnosed FL. All treated patients received rituximab-containing standard regimens. To go beyond the identification of gene-coding events, we developed a very large panel of 110 Mbp covering exonic (~40Mbp) and non-exonic regions (~70Mbp) of interest to enable a wide range of genomic analysis including mutation calling in both coding and non-coding regions, rearrangement detection, viral identification, and copy number analysis. In addition to the whole exome, we extended coverage to include introns, promoters, and untranslated regions of all known driver genes in cancer. We included the entirety of the immunoglobulin loci, T-cell receptor loci and CD3 loci to detect clonotypes and rearrangements. We also included lymphoma-relevant long non-coding RNAs, microRNAs, enhancers, and breakpoint-prone regions. For viral detection, we targeted the genomes of eight cancer-related viruses: Epstein-Barr virus, human papillomavirus, human immunodeficiency virus, hepatitis B, hepatitis C, Kaposi's sarcoma-associated herpesvirus, human T-lymphotropic virus, and Merkel cell polyomavirus. In addition, to enable high resolution identification of copy number variation (CNV) calls, the entire genome was tiled with probes spaced 10kb apart. DNA and RNA were extracted from all tumors and their paired normal samples, prepared into DNA and RNA sequencing libraries and subjected to sequencing on the Illumina platform to a targeted coverage of 150X. Somatic events were identified and further filtered to identify driver events in both coding and non-coding regions. FLs demonstrated a significant degree of genetic heterogeneity with over 100 genes mutated with a frequency of at least 2%. Nearly 100% of FL cases had a mutation in at least one chromatin-modifying gene. The most frequently mutated genes in follicular lymphoma were KMT2D, BCL2, IGLL5 and CREBBP. In addition, we identified frequent mutations in SPEN, BIRC6 and SETD2. To our knowledge, this is the first description of alterations in these genes in FL. Transcriptome analysis indicated a strong correlation between BIRC6 mutations and the previously described immune response 2 signature that is associated with a poor prognosis. We further performed unbiased clustering of genetic alterations in these FL cases. We identified a cluster that was specifically enriched in BCL6 and TP53 alterations and was strongly associated with grade 3 FLs which are predicted to have poorer outcomes with low intensity therapies. We further examined the genetic profiles of 1001 DLBCLs in comparison to this cohort of FLs. Our data indicate a continuum of highly overlapping genetic alterations with DLBCL displaying more complex patterns that included alterations in MYC, TP53 and CDKN2A (mainly copy number losses), indicating shared pathogenetic mechanisms underlying FL and DLBCL, particularly those germinal center B cell origin. Disclosures Koff: Burroughs Wellcome Fund: Research Funding; V Foundation: Research Funding; Lymphoma Research Foundation: Research Funding; American Association for Cancer Research: Research Funding. Leppä:Roche: Honoraria, Research Funding; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bayer: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen-Cilag: Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees. Gang:ROCHE: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees. Hsi:Abbvie: Research Funding; Eli Lilly: Research Funding; Cleveland Clinic&Abbvie Biotherapeutics Inc: Patents & Royalties: US8,603,477 B2; Jazz: Consultancy. Flowers:AbbVie: Consultancy, Research Funding; Denovo Biopharma: Consultancy; BeiGene: Consultancy, Research Funding; Burroughs Wellcome Fund: Research Funding; Eastern Cooperative Oncology Group: Research Funding; National Cancer Institute: Research Funding; V Foundation: Research Funding; Optimum Rx: Consultancy; Millenium/Takeda: Research Funding; TG Therapeutics: Research Funding; Gilead: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Karyopharm: Consultancy; AstraZeneca: Consultancy; Pharmacyclics/Janssen: Consultancy, Research Funding; Spectrum: Consultancy; Bayer: Consultancy; Acerta: Research Funding; Genentech, Inc./F. Hoffmann-La Roche Ltd: Consultancy, Research Funding. Neff:Enzyvant: Consultancy; EUSA Pharma: Honoraria, Membership on an entity's Board of Directors or advisory committees. Fedoriw:Alexion Pharmaceuticals: Other: Consultant and Speaker. Reddy:Genentech: Research Funding; BMS: Consultancy, Research Funding; Celgene: Consultancy; KITE Pharma: Consultancy; Abbvie: Consultancy. Mason:Sysmex: Honoraria. Behdad:Loxo-Bayer: Membership on an entity's Board of Directors or advisory committees; Thermo Fisher: Membership on an entity's Board of Directors or advisory committees; Pfizer: Other: Speaker. Burton:Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel; Celgene: Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees. Dave:Data Driven Bioscience: Equity Ownership.

Description: Abstract 800 Mantle cell lymphoma (MCL) is a B-cell non-Hodgkin lymphoma (NHL) accounting for ~6% of all NHL. It is sensitive to combination chemotherapy, but remission durations are short without approaches such as stem cell transplantation (SCT). Most patients are incurable, but the clinical course is variable, with some patients succumbing quickly, while others survive 〉10 years. MicroRNAs (miRs) are small, non-coding RNAs that regulate gene expression by inhibiting mRNA translation. miRs are useful in the prognostic assessment of tumors, but work to date examining differences between MCL and normal lymphoid tissues, have only identified 2 miRs involved in MCL prognosis (Zhao JJ, Blood, 2010; Di Lisio L, Leukemia, 2010). We used a novel approach to identify a prognostic miR signature in MCL. We hypothesized that a miR signature defining aggressiveness can be obtained by comparing miR expression profiles of aggressive NHL with indolent NHL, and that this signature when applied to a set of MCL cases, may aid in MCL prognosis. Total RNA was extracted from 135 formalin-fixed paraffin-embedded samples obtained at primary diagnosis (Table 1). RNA from a training set of 19 indolent and 20 aggressive NHL cases was analyzed on a high-throughput quantitative real-time PCR (qRT-PCR) platform assessing the expression of 365 miRs and 3 endogenous controls (TaqMan Human MicroRNA Array v1.0: TLDA, ABI) using the DDCt method. A two-sample Wilcoxon Rank sum test corrected for false discovery rate was used to assess the significance of differential expression for each miR between aggressive and indolent NHL. The 14 most significantly differentially expressed miRs (p

Description: Acute promyelocytic leukemia (APL) is characterized by accumulation of abnormal promyelocytes in the bone marrow and peripheral blood, and sensitivity to treatment with all-trans retinoic acid. APL cases have a balanced chromosomal translocation involving retinoic acid receptor alpha (RARA) on chromosome 17. The resulting fusion proteins (X-RARA) are aberrant transcription factors and block ATRA-induced neutrophil differentiation. Loss of RARA signalling impairs granulopoiesis, but is not sufficient to cause a leukemic phenotype. We elucidated the identities of additional signalling pathways, which can potentially cooperate with X-RARA in APL, that are commonly modulated by multiple X-RARA. We used the U-937 hematopoetic cell line retrovirally transduced with NPM-RARA (Kamel-Reid et al, 2003), and NuMA-RARA, in addition to NB4 cells (expressing PML-RARA) to determine the common genes and pathways deregulated in APL. Gene expression analysis was carried out on RNA harvested in triplicate from control and X-RARA expressing cell lines, using the Affymetrix U133Plus2 array platform. Gene expression and pathways analysis of array data was carried out using a suite of analysis tools. Array data were validated in an independent sample set by real-time quantitative PCR. We observed a total of 311 genes deregulated at least 2-fold by NuMA-RARA (192 up-regulated, 119 down-regulated), 393 genes deregulated by NPM-RARA (292 up-regulated, 101 down-regulated), and 2056 genes deregulated by PML-RARA (1097 up-regulated, 959 down-regulated). A total of 65 genes, in 5 major interaction networks, were commonly deregulated by all three X-RARA (42/65 up-regulated, 23/65 down-regulated). The majority of these genes are involved in cellular signalling (14 genes, p-value 1.57E-07–7.77E-3), transcription (13 genes, p-value 5.68E-7–3.91E-3), cell proliferation (25 genes, p-value 9.73E-7–7.77E-3), apoptosis (26 genes, p-value 9.96E-7–7.71E-3), and cell movement (17 genes, p-value 1.43E-6–7.60E-3). Genes involved in the CEBPA interaction network (GFI1, TRIB2, ELA2), as well as other genes that we anticipated to be deregulated in APL including ID1, MMP9, and JUN were found through this analysis. NF-kB (p-value 2.10E-3), AHR (p-value 2.12E-3), IL-6 (p-value 5.40E-3), and G-protein coupled receptor (p-value 7.45E-3) signalling were among the top canonical pathways determined to be altered by X-RARA. Over-expression of a number of NF-kB downstream transcriptional targets, including VEGF, IL8, MMP9, cIAP2, and TNFAIP3, were also observed in multiple X-RARA expressing cell lines. In addition, in vitro results were compared to NuMA-RARA gene targets identified in primary bone marrow cultures derived from the hCG-NuMA-RARA transgenic mouse model (Sukhai et al, 2004). We observed that pathways involved in cell signalling, cell death, gene expression, proliferation, and cell cycle were significantly deregulated in both mouse and human datasets, indicating that these pathways may be important cooperating events in APL. Our data represent the first comparison of the genetic profiles of the variant fusion proteins NPM-RARA and NuMA-RARA in a haematopoietic cell system. Our studies are a significant step in identifying key targets that cooperate with X-RARA in the development of APL.