ALBERT

Description: The importance of aberrant signal transduction in the development and progression of cancers including multiple myeloma (MM) is well recognized, although the detailed regulation of signaling networks in relation to oncogenic mutations remains incompletely understood. However, this subject is becoming increasing relevant to clinical oncology due the rapid development of biological-based therapies that can target signaling pathways. Analytical methods that can be applied to clinical samples to measure complex populations of cells and phenotype them for multiple activation states are now feasible due to the recent advances in intracellular signal techniques, flow cytometry and phospho-antibodies. Using multi-parameter flow cytometry, we monitored phospho-protein responses to activators/cytokines and signal transduction inhibitors in a panel of 14 extensively characterized human MM cell lines with heterogeneous molecular abnormalities. A panel of 4-phospho-specific antibodies: anti-pS6, anti-ERK1/2, anti-pAKT and anti-pSTAT3 that represent downstream target genes of signaling pathways known to play central roles in myelomagenesis were used in the initial analysis. Sixteen conditions (basal, inhibitor, activator alone, activator and inhibitor) were studied to generated 64 readouts designed to survey altered signal transduction in the 14 cell lines. We collected data on unstimulated cells and cells stimulated for 7–10 min with IL-6, IGF-1 or FGF or cells inhibited with the signal transduction inhibitors U0126 (MEK), rapamycin (mTOR) or LY294002 (PI3-K). Repeat measurements were collected and the technique and monoclonal antibodies displayed a high level of reproducibly. In contrast, the basal, cytokine and inhibitor responses between cell lines varied considerably reflecting the molecular heterogeneity at the level of signaling responses. The protocols that have been refined and validated in myeloma cell lines are now being applied to primary bone marrow samples from MM patients. Although the same size thus far is small, phospho-protein responses among primary CD138 positive myeloma cells show considerable induction and variance of AKT, MAPK, STAT3 and pS6 phosphorylation. In some MM tumor samples treatment with inhibitors suggest constitutive activation of these signaling pathways while in others the nodes remain activable with phosphorylation above the basal state following stimulation. The data further suggests that MAPK phosphorylation following aFGF stimulation displays significant variance among MM samples and correlates with the detection of t(4;14) translocation by FISH analysis. Additional samples are being assessed and correlation of phospho-protein responses with clinical parameters and cytogenetics will be reported. The data demonstrate that multi-parameter flow cytometry can be applied to myeloma tumor samples to study the phospho-proteome and that considerable heterogeneity exists at the level of signaling responses.

Description: Waldenström’s macroglobulinemia (WM) is an incurable low-grade lymphoproliferative disorder characterized by bone marrow (BM) infiltration of a clonal population of small B-lymphocytes, plasmacytoid lymphocytes and plasma cells that secrete monoclonal IgM antibody. Because it is difficult to obtain tumor metaphases for karyotype studies, few recurrent chromosomal abnormalities have been reported and the genetic basis of the disease remains poorly defined. Therefore, we performed a comprehensive high-resolution study to identify genomic abnormalities involved in WM pathogenesis. Fifty-seven WM patients were analyzed using a combination of array-based comparative genomic hybridization (aCGH)(N=42); gene expression profiling (GEP)(N=22), DNA sequencing (N=24) and cIgM-FISH (N=57). Agilent 244A and Affymetrix U133 platforms were used in the aCGH and GEP experiments, respectively. An NF-κB index was calculated from GEP data, as a surrogate marker of NF-κB transcription activity. NFKB2 sub cellular localization was determined by immunofluorescence staining. Overall, 83% of samples have aCGH defined chromosomal abnormalities, with a median of 3 abnormalities per patient (range 0 to 27). We identified 16 recurrent regions of copy number change found in 〉5% (3 or more patients); 10 deleted and 6 amplified regions. The most common abnormality was the entire or partial deletion of 6q, identified in 40% of cases. Four nonoverlapped minimal deleted regions were identified on 6q (MDR1 to MDR4), each of them being present in at least 14 of 17 patients with the abnormality. Gain of 6p was the second most common abnormality (17%) and its presence was always concomitant with 6q loss. Other recurrent deletions were 13q14 (10%) and 7q22, 8p, 11q22-q23, 11q23-q24 and 17p11-p13 (7% each). Copy gains were identified as partial or entire gains of chromosomes 18 (17%), 4 (12%) and 3 (10%), 8q (10%) and Xq27.1-q28 (10%). Three patients had either homozygous deletions or LOH with mutations affecting both alleles of TRAF3 on 14q32. TRAF3 inactivation was correlated with an increased NF-kB transcriptional signature and it was associated with activation of the non-canonical NFkB pathway. Additionally, we identified the inactivation of TNFAIP3, another negative regulator of the NF-kB pathways, in one of 24 patients. Finally, interstitial deletions identified in 4 patients at 13q14 identified a 1.1 Mb MDR, including MIRN15A and MIRN16-1. These findings confirm that focal 13q14 deletion is not restrict to B-CLL and that the MIRN15A/MIRN16-1 abnormalities might be common to several indolent B-cell diseases. Overall, we identified TRAF3 and TNFAIP3 inactivation in 5.3% and 2.4%, respectively. To our knowledge, this is the first study showing the inactivation of bona fide tumor suppressor genes in WM patients. Furthermore, these genes are negative regulators of NF-kB signaling pathway, highlighting its biologic importance in sustaining and limiting growth in WM. Mutational activation of this pathway, which is normally activated by ligand-receptor interactions within the BM microenvironment, suggest a therapeutic role for inhibitors of NF-KB pathway activation in the treatment of WM.

Description: Background: Thalidomide and its analogue lenalidomide have high response rates among patients with newly diagnosed as well as previously treated myeloma. Pomalidomide (CC4047) is the newest immunomodulatory (IMiD) agent that has shown single-agent activity in phase I studies. We report on the first Phase 2 trial of pomalidomide combined with low dose dexamethasone (Pom/dex) in patients with relapsed or refractory multiple myeloma. Methods: 37 patients (21 male and 16 female) were enrolled. Pomalidomide was given orally 2 mg daily on days 1–28 of a 28-day cycle. Dexamethasone was given orally at a dose of 40 mg daily on days 1, 8, 15 and 22 of each cycle. Response was assessed by the International Myeloma Working Group Uniform Response criteria. All patients received aspirin 325 mg daily as prophylaxis against DVT. Results: The median age was 66 years (range, 40 – 88). All patients were evaluable for response and toxicity, and all analysis were done on intent to treat basis. All patients had received prior therapy; 38% had 3 prior regimens; 35% had 2 prior regimens and 27% had one prior regimen. 76% had previous autologous stem cell transplant (ASCT) and 24% had 2 prior ASCT. 62% had previous IMiD therapy. Toxicity was mild and consisted primarily of myelosuppression. Grade 3 neutropenia occurred in 31%; grade 3 thrombocytopenia 3%; grade 3 anemia 3 %. Other grade 3/4 toxicities seen in less than 5% pts included: diarrhea, atrial fibrillation, pneumonia, dehydration and renal insufficiency. 16 % had grade 1/2 neuropathy. No grade 3 neuropathy was seen and there have been no thromboembolic events. Thirty (81%) patients are continuing study treatment. Seven patients have discontinued treatment due to: disease progression (5), died on study (1) and the medical doctor’s discretion (1). Twenty three of 37 patients (62%) achieved an objective response to therapy; including 9 (24%) with VGPR; 14 patients (38%) with PR; 6 (16%) with stable disease. Objective responses were seen in 4 of 13 patients (29%) who were refractory to lenalidomide. Conclusions: Pomalidomide plus dexamethasone (Pom/dex) is highly active and well tolerated for treatment of relapsed/refractory multiple myeloma with an objective responserate of 62%, including a 29% response rate among patients who are lenalidomiderefractory.

Description: Introduction Over the last 15 years gene expression profiling (GEP) has been used to define myeloma molecular subgroups and to determine clinical prognosis. Two major molecular subgroup classifications have been used: the UAMS which determines 7 subgroups and the TC classification based on the presence of IgH translocations and expression of D group cyclins. For prognosis, although a number of different GEP signatures have been defined, the widely used GEP70 identifies 15% of patients with high risk (HR) disease who have a median PFS and OS of 1.75 and 2.83 years. An ideal classification system would identify clinically relevant subgroups with distinct etiology and biology using standardized techniques. We have examined a large group of patients characterized at multiple genetic levels to optimize the diagnostic approach of newly diagnosed patients going forward. Materials and methods Study subjects included 1349 cases enrolled in Total Therapy trials (median follow up 7.5 years). Gene expression profiling was used to determine GEP70 risk status, molecular subgroup by UAMS and TC classifications, and to devise a new and extended TC classification (TC10). Interphase FISH associated with IgH translocations and 1q+ and 17p- were used to build GEP proxies. Data from mutational analysis generated by the FoundationOne targeted sequence panel was also incorporated. Results were validated on the UK MRC MyelomaIX and Hovon65/GMMG-4 studies. Results An initial agnostic analysis of GEP data using sparse k-means clustering verified the existence of TC based groups. Six groups were identified that corresponded overwhelmingly with known TC subgroups; CCND1-t(11;14), D1-HRD, D2-HRD, MMSET, MAF/CCND2, and CCND3. Further comparisons between the molecular subgroup and TC classifier revealed that the UAMS 7 subgroups clustered strongly within one predominant TC group: CD-1 and CD-2 to t(11;14), HY to D1, LB and PR to D2, MF to t(14;16) or t(14;20), and MS to t(4;14). As the UAMS molecular subgroups are largely contained within the TC framework, we aimed to extend the TC by developing the TC10. To extend the known TC subgroups, unsupervised clustering was applied to the 3 largest subgroups [t(11;14), D1, and D2] to determine the strongest single divisor within each respective subgroup. The dominant feature within the t(11;14) cases was CD20 expression, while the D1 and D2 subgroups both split according to RRAS2. CD20 is associated with PAX5 and VPREB3 expression, and RRAS2 is associated with decreased PTP4A3 and increased TNFAIP3 and BIRC3 expression. RRAS2 activation within D1 subgroup and CD20 activation within t(11;14) cases corresponds to an increased time to response to induction therapy suggesting they constitute important biological subgroups. The TC10 combines the known etiologic subgroups of the TC with functionally relevant subdivisions to create 10 novel subgroups: t(11;14) CD20+/-, D1: RRAS2+/-, D2: RRAS2+/-, t(4;14), t(14;16), t(14;20), and t(6;14). Analysis of mutational data revealed that RRAS2 and CD20 activation within the D1, D2, and t(11;14) subgroups reduced the number of mutations in the MAPK pathway. Further mutational analysis revealed that median mutational load was highest in t(14;16) and lowest in D2: RRAS2+ subgroups. The GEP70 score identifies 15% of patients with HR disease and is specific for this purpose. In an analysis of risk assessment methods, we compared GEP detected adverse lesions [t(4;14), t(14;16), t(14;20), 17p- and 1q+] with the GEP70 and revealed that GEP70 HR identified samples have lower OS rates than cases with more than one adverse lesion (validated in external sets). GEP70 HR segregates non-uniformly across molecular subgroups as over 40% of all HR cases are found in the TC10 t(4;14), t(14;16), and t(14;20) subgroups. GEP70 HR cases also have a higher mutational load than low risk cases. Furthermore, GEP70 HR is uniquely associated with 1q+ and 17p- as cases with at least one of these adverse lesions are 4.9 times as likely to be GEP70 HR as cases with neither. Conclusion GEP profiling has a central role in simplifying and standardizing the molecular subgroup designation and risk stratifying of MM patients. The GEP70 risk score reliably identifies HR cases and outperforms FISH in risk assessment, even in validation data sets. The TC10 provides a classification system that improves upon previous methods by defining both etiological and functionally meaningful subgroups. Disclosures Stein: University of Arkansas for Medical Sciences: Employment. Davies:University of Arkansas for Medical Sciences: Employment; Celgene: Consultancy; Janssen: Consultancy; Millenium: Consultancy; Onyx: Consultancy. Heuck:University of Arkansas for Medical Sciences: Employment; Celgene: Consultancy; Janssen: Other: Advisory Board; Millenium: Other: Advisory Board; Foundation Medicine: Honoraria. Weinhold:University of Arkansas for Medical Sciences: Employment; Janssen Cilag: Other: Advisory Board. Chavan:University of Arkansas for Medical Sciences: Employment. Thanendrarajan:University of Arkansas for Medical Sciences: Employment. Epstein:University of Arkansas for Medical Sciences: Employment. Yaccoby:University of Arkansas for Medical Sciences: Employment. Zangari:University of Arkansas for Medical Sciences: Employment; Novartis: Research Funding; Onyx: Research Funding; Millennium: Research Funding. van Rhee:University of Arkansa for Medical Sciences: Employment. Kaiser:Janssen: Honoraria; Amgen: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding; BristolMyerSquibb: Consultancy; Chugai: Consultancy. Sonneveld:Janssen-Cilag, Celgene, Onyx, Karyopharm: Honoraria, Research Funding; novartis: Honoraria. Goldschmidt:Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees; Onyx: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bristol-Myers Squibb: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen-Cilag: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Millenium: Honoraria, Research Funding, Speakers Bureau; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees; Chugai: Honoraria, Research Funding, Speakers Bureau; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Barlogie:University of Arkansas for Medical Sciences: Employment. Morgan:Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; MMRF: Honoraria; CancerNet: Honoraria; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; University of Arkansas for Medical Sciences: Employment; Weismann Institute: Honoraria; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees.

Description: Background: Ixazomib is an experimental, orally bioavailable, proteasome inhibitor that has demonstrated anti-tumor activity in relapsed multiple myeloma (MM). In the dose escalation studies, ixazomib was tolerated up to a dose of 5.5 mg given every week as a single agent, while a dose of 4 mg was utilized in the combination studies with lenalidomide. We undertook this study to examine the efficacy and tolerability of the two doses of ixazomib in combination with dexamethasone in patients with relapsed MM. Patients and methods: This was a randomized phase 2 study of two doses of ixazomib (4mg; Arm A or 5.5 mg; Arm B) given weekly for three weeks with a week off along with weekly dexamethasone (40 mg) in patients with relapsed MM, who are proteasome inhibitor na•ve (including bortezomib) or have received less than 6 cycles of therapy with bortezomib and had a PR or better with no progression at the time of discontinuation. The primary objective was to determine the confirmed overall response rate (〉=PR); secondary objectives included progression free and overall survival. A total of 71 patients were accrued from February 2013 to April 2015; one patient was ineligible. Results: Baseline characteristics were similar in the two arms; median age across the study was 70 years (46-84); 53% were male. Median number of prior therapies was 4 (range 2-6); 90% of the patients had prior IMiDs, 70% had prior transplant and 29% had prior bortezomib. At a median follow up of 10 months, 17 (49%) and 19 (54%) of patients had disease progression in arms A and B respectively with 12 (34%) patients in each arm still continuing on treatment. All patients in each arm were evaluable for response; the overall response rates were 31% in arm A (95%CI: 17-49) and 51% (95%CI: 34-69) in Arm B. The depth of response, event free survival and overall survival are outlined in Table 1. Among the patients with no prior bortezomib exposure the response rates were 38% for Arm A and 52% for Arm B. The treatment was well tolerated with 2 patients in each arm discontinuing treatment for adverse events; there were no on study deaths. A grade 3 or higher AE that was at least possibly related to treatment was seen in 21% and 54% in Arms A and B respectively; with 15% and 37% hematologic and 6% and 29% non-hematologic AEs. The most common attributable toxicities encountered included fatigue, thrombocytopenia, diarrhea and nausea with more grade 3 toxicities among Arm B. Peripheral neuropathy, possibly related to ixazomib, was seen in 55% (only grade 1 or 2) in arm A and 43% (2 patients with grade 3) in Arm B. Toxicities led to dose reduction of ixazomib in 17% and 43% of patients in Arm A and B respectively; the median number of cycles administered were 5 (1-24) and 5 (1-22) respectively. Conclusions: Ixazomib in combination with dexamethasone was well tolerated with significant anti-myeloma activity in this group of patients with relapsed MM. Deep responses including stringent CR were observed. The higher dose of ixazomib appears to be associated with a higher response rate but with higher rate of adverse events requiring dose reductions. Table 1. Treatment outcome in all patients Arm B (4 mg) (N=35) Arm C (5.5 mg) (N=35) Response Rate 31% (95%CI: 17-49) 51% (95%CI: 34-69)  No. of Responders 11 18   sCR 0 1   CR 1 0   VGPR 7 8   PR 3 9   MR 5 1 Median Overall Survival1 NA NA  6 Months 100% 100% Median Event Free Survival1,2 8.4 mos (95%CI: 4.3-13.2) 8.2 mos (95%CI: 3.8-16.3) %Event Free at 6 Months 60% (95%CI: 45-81) 60% (95%CI: 45-81) Median Duration of Response1 16.7 mos (95%CI: 9.3-22.0) 16.3 mos (95%CI: 7.0-20.1) Median Time to Response 1.1 mos (range: 0.8-3.6) 1.0 mos (range: 0.8-7.5) CI: confidence interval; mo: month; NA: not attained 1Kaplan Meier 2Event-free survival time is defined as the time from registration to the first of disease progression, death due to any cause, or subsequent treatment for multiple myeloma. Disclosures Kumar: Celgene: Consultancy, Research Funding; Sanofi: Consultancy, Research Funding; Skyline: Consultancy, Honoraria; Onyx: Consultancy, Research Funding; Novartis: Research Funding; Janssen: Consultancy, Research Funding; Takeda: Consultancy, Research Funding; BMS: Consultancy.

Description: While multiple myeloma (MM) is almost invariably preceded by asymptomatic monoclonal gammopathy of undetermined significance (MGUS) and/or smoldering MM (SMM), the alterations of the bone marrow (BM) microenvironment that establish progression to symptomatic disease are circumstantial. Our aim was to identify changes in the BM microenvironment eliciting angiogenesis in MM. We have found that in Vk*MYC mice harboring oncogene-driven plasma cell proliferative disorder, the progression from asymptomatic to symptomatic MM was characterized by substantial modifications of the BM microenvironment, including a switch from a T helper type 1 (Th1) to a Th2 response, and accumulation of CD206+Tie2+ macrophages, which eventually favored angiogenesis and increased in microvessel density (MVD). Notably, MVD was also increased at diagnosis in the BM of MGUS and SMM patients that subsequently progressed to MM when compared with MGUS and SMM that remained quiescent. These findings suggest a multistep pathogenic process in MM, in which the immune system may contribute to angiogenesis and disease progression. They also suggest investigating MVD in asymptomatic patients as prognostic factor for the progression and outcome of this disease. Disclosures No relevant conflicts of interest to declare.

Description: The search for novel and clinically effective anti-myeloma therapies has been hampered by a paucity of good pre-clinical animal models. Most established animal models of multiple myeloma (MM) fail in one or more crucial features to resemble human MM, frequently exhibiting extramedullary tumors or lacking a competent immune system. In addition, competing models are either too expensive or time consuming to generate and maintain. Finally, no model has been shown to reliably predict both drug response and drug inactivity. We have previously described a C57Bl6/J transgenic mouse model in which the expression of the human c-myc oncogene is activated in post-germinal B cells by somatic hypermutation. These mice (Vk*myc) spontaneously develop monoclonal gammopathies and plasma cell expansion beginning at 20 weeks of age. However, in contrast to other models, their plasma cells cannot be found in secondary lymphoid tissues. Now, we report that this model closely reproduces the clinical behavior of human MM. Serum protein electrophoresis (SPEP) as well as ELISA for serum IgG demonstrate that the incidence and quantity of monoclonal paraproteinemia are greatly elevated in the Vk*myc mice as compared to age matched wild type C57Bl6/J controls (50 weeks mean IgG 1.92g/dL Vk*myc vs 0.2g/dL controls; peak IgG levels up to 7.5g/dL). As these mice age, their paraproteins continue rising and remain far higher than that of controls at every time point. Mice with significant paraproteinemia demonstrate marrow with up to 50% plasma cells with evidence of a low proliferative index, similar to what is observed in human MM and unlike what is seen in other models of MM. Anemia is observed, with a mean hemoglobin of 8.9g/dL in the Vk*myc mice vs 13.4g/dL in the wild type. Vk*myc mice analyzed show marked bone thinning with a 20% reduction in total bone volume and in the number of trabeculae per unit area as shown by microCT. In addition a 15% reduction in bone mineral density was demonstrated in affected mice. We next demonstrated the efficacy of 3 drugs, used commonly in clinical practice to treat myeloma (melphalan, dexamethasone and bortezomib). These were given as single courses of daily IP injections for 5 days, for the first two drugs, and bi-weekly IP for 4 weeks for the third. As early as two weeks post treatment, a statistically significant reduction in serum paraprotein levels was observed in the treated mice versus vehicle treated controls. The reductions were maximal at 21d post treatment in the melphalan (−77.2%±39 p

Description: In an attempt to identify novel genetic abnormalities in multiple myeloma (MM) we analyzed 68 MM patient samples and 42 human myeloma cell lines (HMCL) with high-resolution (60kb) array-based comparative genomic hybridization (aCGH). We concentrated on bi-allelic genomic deletions with the expectation that these regions might contain novel tumor suppressor genes and identified a common abnormality at 14q32. Fine mapping of the 14q32 microdeletion by PCR demonstrated a 45 kb minimal deletion encompassing two genes; TRAF3, a negative regulator of the non-canonical NF-kB pathway, and AMN. To determine the frequency of copy number abnormalities of this region a cohort of 161 patients were screened with a FISH probe mapping to the minimally deleted region. This identified 7 (4.4%) patients with bi-allelic deletion and 19 (11.8%) patients with a single copy of the target region. Sequencing of all TRAF3 coding exons in 62 patients and 42 HMCL identified inactivating mutations in 9 patient samples and 4 HMCL. Overall, the incidence of TRAF3 inactivation, bi-allelic deletion or mutation, is 7/42 (16.7%) in HMCL and 12/62 (19.4%) in patients, making it one of the most common genetic abnormalities identified in MM. Importantly, dysregulation of NF-kB pathways is a common event in MM, but the mechanism for this dysregulation is largely unknown. Although TRAF3 is a negative regulator of the non-canonical NF-kB pathway it has not previously been implicated in cancer. Therefore, we tested the tumor suppressor function of TRAF3 by reintroducing TRAF3 into HMCL harboring TRAF3 abnormalities using an adenovirus gene transfer system. Expression of TRAF3 in HMCL with TRAF3 abnormalities rapidly reversed cellular processing of NFKB2 from p100 (an inactive isoform) to p52 (active) and additionally led to a 60% reduction in cellular proliferation (range, 10–89%) associated with Go/G1 cell cycle arrest and induction of cell death by apoptosis. At 48 hrs post infection the proportion of cells entering S-phase or G2/M declined by 31% (range, 8.1–56.1) and the proportion undergoing apoptosis increased by 28% (range 11.7–47.4%). In contrast, over-expression of TRAF3 in control HMCL without TRAF3 abnormalities had no effect. Overall, TRAF3 is identified as a novel tumor suppressor that regulates the non-canonical NF-kB pathway and is inactivated in ~ 20% of MM patients. Given the involvement of the NF-kB pathway in multiple human malignancies and the near constitutive expression of TRAF3 we propose that inactivation of TRAF3, a novel tumor suppressor identified for the first time in this study, may occur in other cancers. In this regard, we have recently identified a Burkitt lymphoma cell line that does not express TRAF3 and thus has constitutive processing of p100 to p52. The clinical and therapeutic consequences of this finding and its frequency in other tumor types are currently the focus of further investigation. In conclusion, the abnormalities identified in this study represent the first mutations identified that cause constitutive NF-kB activation in MM.

Description: The study of genomic aberrations in chronic lymphocytic leukemia (CLL) has yielded critical information, now routinely used for the prognostication of patients. An unbiased search for genome wide areas of copy number change is needed to identify possible primary genetic events in CLL and to elucidate their relationship to other known cytogenetic factors, such as deletions of 13q14, 11q23 and 17p13 and trisomy 12. Here we report on a study where we used a 60-mer oligo array-based Comparative Genomic Hybridization (aCGH, 44B platform from Agilent Technologies, Palo Alto, CA). We observed the most common genetic aberrations in CLL and in similar frequencies as would be predicted for CLL (e.g. 44% showing deletions of chromosome 13q14). Among those patients, 45% had no apparent other aberration. Of great interest, small bi-allelic deletions of chromosome 13, which predominantly involved the DLEU1 and DLEU2 locus, were detected in 4 patients (16%). Deletions of 11q23 were observed in 6 cases (24%), and while some involved the ATM locus one did not, casting doubt on the precise gene deregulated by these deletions. Large deletions of the whole 17p-arm were detected in three cases (12%). Trisomy 12 was present in only two cases (8%). No other trisomies were detected and also small regions of copy gain were uncommon. Monosomy of chromosomes 19, X and Y were present in three separate cases. Large deletions of chromosome 2p were seen in two cases, but an additional case had a small deletion involving the ALK gene. This case also had a breakpoint at chromosome 5 involving the NMP1 locus, suggestive of a t(2;5). A recent study (Mayr et al., Blood 2006) indicates that chromosomal translocations in CLL are present in 33% and were associated with a dismal prognosis. In our analysis we detected several breakpoints indicative of translocations. Detailed study is necessary to elucidate possible molecular events associated with these translocations. Other small regions of DNA copy loss were found at several locations throughout the genome. Regions of interest are shown in the table. In summary we show that multiple areas of recurrent genomic gain and loss can be identified in clonal cells of CLL and should lead to further insights into the understanding of disease pathogenesis. Chromosome Location Gene(s) of interest Loss 6q24.3 LATS Loss 10q23.3 LG11 Loss 10q24.2 PAX2, WNT8B, TLX1, POLL, NFKB2 Loss 11p15.4 PPFIBP2 Loss 12p13 TNFRSF1A and 7 Loss 15q22.1 TCF12 Loss 19p13.3 BAX, RUVBL2 Loss 20q11.2 TP53INP2 Loss 20q13.1 WFDC13

Description: Background: Outcomes in multiple myeloma (MM) have improved significantly over the years but disparities in outcomes exist among MM patients (pts) belonging to different racial subgroups. Previous studies have explored healthcare access and utilization disparities for pts of different races as potential causes, but genomic differences, which could alter disease biology and clinical behavior, have not been studied. We utilized the MMRF CoMMpass database, which prospectively captures clinical and molecular characteristics of MM patients to explore race-based differences at the genomic level. Methods: The publically available CoMMpass trial database (data release version IA8) was utilized. Pts with race category of White (total n=698) and non-White (total n=223, comprising 129 Blacks, 19 Asians and 45 others) were analyzed for genomics including cytogenetics (fluorescent in situ hybridization; FISH), tumor diploidy (conventional karyotyping), gene expression profiling (GEP), gene copy number variations (CNV), gene single nucleotide variations (SNV) and genomic translocations analysis focused on genes from the FoundationOne Heme panel¨ (402 genes). GEP was considered significantly different between categories for more than or equal to a 2-fold change for a given gene (p No abnormalities 〉 t(11;14) 〉 1q amplification 〉 Del17p or p53 〉 t(4;14) 〉 Del1p 〉 t(14;16) 〉 t(14;20). Aneuploidy status showed insignificant differences between race groups with ~34% of patients from both groups having no aneuploidy. SNV data was present for 90% of Whites and 57% of non-Whites. Overall, 84% of genes had〉1 SNV (84%), 2% translocations only and 14% had neither SNVs or translocations. SNVs were classified as Non-specific Non-Synonymous coding (NNSCs), Splice-site (SS) or Tier 1 (T1, codon deletion, insertion, frame-shift, etc.). A total of 880 NNSCs SNVs were observed: 670 in Whites across 227 genes, 210 in non-Whites across 120 genes. In whites, 57% of NNSC SNVs consisted of transition-type mutations and 43% as transversions. In non-Whites, transition mutations comprised 64% of all NNSC SNVs and transversions in the remaining 36%. A total of 38 SS SNVs were observed, 30 in Whites and 8 in non-Whites observed in 25 and 6 genes, respectively. In Whites, 57% of SS SNVs were transition type and remaining 43% were transversion. In non-Whites, an equal % of SS transition and transversion mutations were noted. A total of 240 T1 SNVs were noted; 182 in Whites seen in 82 genes; 58 in non-Whites seen 6 genes. In both Whites and non-Whites, frameshifts (41% in Whites, 47% in non-Whites) and stop-gained (46% in Whites, 45% in non-Whites) SNVs were most common. A total of 17 genes with〉10 distinct SNVs were identified in Whites; 5 genes in non-Whites and 4 genes commonly seen in both cohorts (Fig 1B). In Whites, 17 genes were found to have translocations (intrachromosomal TRAF3 and PIK3R2 most common); in non-Whites, 5 genes had translocations (intrachromosomal CIC and EMSY most common). CNV analysis demonstrated 21 genes that were significantly altered with either copy number gain or loss between Whites vs. non-Whites (Fig 1C). Conclusions: We present the first race-based comprehensive genomic analysis utilizing the public interface of the CoMMpass trial. We discovered genomic differences between Whites and non-Whites at several levels including GEP, SNV and CNV, but not at the level of cytogenetics, which are in fact the most commonly performed clinical genomic analysis. Correlation of these variations with MM pt outcomes would be invaluable in understanding disease biology and hopefully mitigating some of the outcome disparities by pt race. As the database grows and becomes more enriched, separate analyses for Blacks, Asians and Hispanics would be attempted. Acknowledgments: We would like to thank the MMRF, Ms. Mary Derome and Dr. Jonathan Keats for providing scientific overview and technical support. Disclosures Fonseca: Millennium, a Takeda Company: Consultancy; Millennium, a Takeda Company: Consultancy; AMGEN: Consultancy; AMGEN: Consultancy; Patent: Patents & Royalties: Prognostication of MM based on genetic categorization of FISH of the disease; Patent: Patents & Royalties: Prognostication of MM based on genetic categorization of FISH of the disease; Patent Pending: Patents & Royalties: The use of calcium isotopes as biomarkers for bone metabolisms; Patent Pending: Patents & Royalties: The use of calcium isotopes as biomarkers for bone metabolisms; Celgene: Consultancy; BMS: Consultancy; Bayer: Consultancy; Novartis: Consultancy; Sanofi: Consultancy; Celgene: Consultancy; Janssen: Consultancy; Millennium, a Takeda Company: Consultancy; BMS: Consultancy; AMGEN: Consultancy; Bayer: Consultancy; Patent: Patents & Royalties: Prognostication of MM based on genetic categorization of FISH of the disease; Novartis: Consultancy; Patent Pending: Patents & Royalties: The use of calcium isotopes as biomarkers for bone metabolisms; Sanofi: Consultancy; Janssen: Consultancy; Millennium, a Takeda Company: Consultancy; AMGEN: Consultancy; Patent: Patents & Royalties: Prognostication of MM based on genetic categorization of FISH of the disease; Patent Pending: Patents & Royalties: The use of calcium isotopes as biomarkers for bone metabolisms. Ailawadhi:Takeda Oncology: Consultancy; Amgen Inc: Consultancy; Novartis: Consultancy; Pharmacyclics: Consultancy.