ALBERT

Description: Key Points Multiple myeloma cells inhibit myeloma-specific T cells through expression of carcinoembryonic antigen-related cell adhesion molecule-6.

Description: Introduction: Gene expression profiling (GEP) has significantly contributed to the elucidation of the molecular heterogeneity of multiple myeloma plasma cells (MMPC) and only recently it has been recommended for risk stratification. Prior to GEP MMPC need to be enriched resulting in an inability to immediately freeze bone marrow aspirates or use RNA stabilization reagents. As a result in multi-center MM trials sample processing delay due to shipping may be an important confounder of molecular analyses and risk stratification based on GEP data. In order to determine the impact of "shipping delay" on MMPC gene expression we analyzed a set of 573 newly diagnosed German MM patients including 230 in-house and 343 shipped samples. Materials and Methods: We included publicly available GEP data of newly diagnosed MM patients treated in the GMMG HD4 and MM5 trials. All samples had been processed in a central laboratory in Heidelberg and include 85 HD4 and 145 MM5 in-house and 97 HD4 and 246 MM5 shipped samples. Prediction of sample status was done on publicly available GEP, including data from the UK, UAMS and MMRC. Differential gene expression was assessed using empirical Bayes statistics in linear models for microarray data. Predictor for shipment status was generated on the MM5 cohort using prediction analysis for microarrays. Pathway enrichment analysis was done using WebGestalt. Risk signatures and molecular subgroups were obtained as previously described. Fisher's exact test was used to compare the subgroup distribution between cohorts. If applicable, results were corrected for multiple testing using the Benjamini-Hochberg method. In all statistical tests, an effect was considered statistically significant if the P-value of its corresponding statistical test was not greater than 5%. Results: Applying the Goeman's global teston the MM5 set showed that "shipping delay" significantly impacted global gene expression (P 1.5-fold and 826 a 〉2-fold difference in expression level. Differentially expressed genes were enriched in processes like ribosome biogenesis, cell cycle, and apoptosis. We observed significantly lower proliferation rates in shipped samples (P

Description: Introduction In multiple myeloma, initially, there are increased numbers of osteoclasts showing increased activity, but bone formation by osteoblasts is keeping step. In later stages, parts of the bone remodeling compartments are disrupted by the interaction with myeloma cells leading to increased bone resorption which can no longer be compensated (myeloma bone disease, uncoupling of bone formation and bone resorption). Lenalidomide and bortezomib have been shown to target both, myeloma cells and the microenvironment: lenalidomide inhibits osteoclastogenesis, bortezomib is also able to stimulate osteoblast differentiation leading to increased bone formation. Aim of this study is to evaluate the impact of bortezomib-based induction treatment, high-dose therapy, and lenalidomide consolidation on alterations of bone turnover, i.e. surrogates of osteoblast- (osteocalcin, OC) and osteoclast- (collagen type I fragments, CTX-I) function, and their induction by myeloma cells (DKK1-level). Methods Serum was collected during routine sampling within the GMMG-MM5 trial (EudraCT 2010-019173-16), and levels of CTX-I, OC, and DKK1 were assessed by ELISA in triplicates using commercially available assays according to the manufacturer’s instructions (RnD Systems and Immunodiagnostic Systems). The following time points were assessed: at inclusion (n=365), after induction therapy with either PAd (n=88) or VCD (n=84), stem cell mobilization using CAD (n=69), high-dose melphalan (n=92), and 2 months lenalidomide consolidation (n=92). Up to now, serum samples of 69 patients were measured sequentially at five time points in line with the GMMG-MM5 trial. DKK1 levels were correlated with the expression in CD138-purified myeloma cells (Affymetrix microarrays, n=365). Results Prior to treatment, CTX-I levels are increased, those of OC decreased compared to healthy donors (uncoupled bone turnover). DKK1 protein levels are increased and correlate with DKK1-expression in myeloma cells. After induction therapy, osteoclast activity (CTX-I) is decreased below normal values. PAd unlike VCD further decreases osteoblast activity (OC-levels); DKK1-levels are normalized. Subsequent treatment further decreases DKK1-levels below normal values and blocks osteoclast function. After 2 months lenalidomide consolidation, no normalization of osteoblast activity is found. Conclusion The main impact on bone turnover by bortezomib-based induction treatment is a reduction of osteoclast activity alongside a decrease in DKK1-levels. During the reported period, no normalization of decreased osteoblast function was observed. Disclosures: Seckinger: Novartis Pharma: Research Funding. Goldschmidt:Novartis Pharma: Research Funding. Hose:Novartis Pharma: Research Funding.

Description: BACKGROUND. The proliferation-rate of primary myeloma cells is a strong adverse prognostic factor in various trials, but not routinely assessed, partially due to effort in obtaining it. AIM. As gene-expression profiling is increasingly considered a standard diagnostics in myeloma, we investigated the possibility to develop a prognostically relevant gene-expression based proliferation index (GPI). PATIENTS AND METHODS. Gene expression was determined by Affymetrix DNA-microarrays in 784 samples including two independent sets of 233 and 345 CD138-purified myeloma cells from previously untreated patients. The GPI was derived by selecting genes associated with proliferation (in terms of gene ontology) differentially expressed in proliferating malignant (human myeloma cell lines) and benign (plasmablastic) cells compared to non-proliferating, non-malignant cells (normal plasma cells and memory B-cells). The GPI comprises the sum of the expression values of 50 genes (ASPM, AURKA, AURKB, BIRC5, BRCA1, BUB1, BUB1B, CCNA2, CCNB1, CCNB2, CDC2, CDC20, CDC25C, CDC6, CDCA8, CDKN3, CEP55, CHEK1, CKS1B, CKS2, DLG7, ESPL1, GINS1, GTSE1, KIAA1794, KIF11, KIF15, KIF20A, KIF2C, KNTC2, MAD2L1, MCM10, MCM6, MKI67, NCAPD3, NCAPG, NCAPG2, NEK2, NPM1, PAK3, PCNA, PGAM1, PLK4, PTTG1, RACGAP1, SMC2, SPAG5. STIL, TPX2, ZWINT). Proliferation of primary myeloma cells was assessed by propidium iodinestaining (n=67). Chromosomal aberrations were assessed by comprehensive iFISH using a set of probes for the chromosomal regions 1q21, 6q21, 8p21, 9q34, 11q23, 11q13, 13q14.3, 14q32, 15q22, 17p13, 19q13, 22q11, as well as the translocations t(4;14)(p16.3;q32.3) and t(11;14)(q13;q32.3). RESULTS. In the two groups, 39 and 32 percent of primary myeloma cells show a GPI above the median plus three standard deviations of normal bone marrow plasma cells, respectively. The GPI is significantly higher in advanced- compared to early-stage myeloma (P=.001) and in patients harboring a gain of 1q21 (n=95, P

Description: Abstract 2987 Background. We have recently shown HIF1A to be expressed in 95.4% of CD138-purified myeloma cell samples from previously untreated patients (n= 329), with significantly higher [lower] expression in case of presence of t(4,14) [hyperdiploidy] vs. patients without the respective aberration. This makes HIF1A an interesting target in myeloma treatment. Additionally, we have shown about 40% of myeloma cell samples to have a proliferation-index above the median plus three standard-deviations of normal bone-marrow plasma cells, and we and others have proven proliferation to be associated with adverse prognosis in myeloma. Here, we report on 2 members of a novel class of sulfonanilides, their preclinical activity and pharmacology, and their dual mechanism of action, targeting HIF1A-signaling and inducing apoptosis via cell cycle arrest and tubulin depolymerization. Patients and Methods. The effect of the novel sulfonanilides ELR510444 and ELR510552 on the proliferation of 20 human myeloma cell lines and the survival of 5 primary myeloma cell-samples cultured within their microenvironment were tested. The results of efficacy studies in in two murine models (RPMI8226-xenograft-model and 5T33-model) are also presented. The mechanism of action was investigated using a variety of in-vitro assays (see below). Results. Preclinical activity in Myeloma. i) The sulfonanilides ELR510444 and ELR510552 completely inhibit proliferation of 20/20 tested myeloma cell lines at low nM concentrations and ii) induce apoptosis in 5/5 primary myeloma cell-samples at 6.4 – 32 nM concentration, without major effect on the bone marrow microenvironment. iii) They significantly inhibit tumor growth (xenograft; RPMI8226 mouse model, 6 mg p.o. bid for ELR510444, 15 mg p.o. bid for ELR510552) and bone marrow infiltration (5T33-model; ELR510444, 6 mg/kg p.o. bid × 4d, rest 3d (cycle)). Mechanism of action. Apoptosis induction and G2/M-block. i) Both compounds lead to caspase-3/7 activation and subsequent apoptosis with cellular EC50 values of 50–100 nM. ii) The compounds induce an initial cellular arrest in G2/M and a significant tubulin depolymerizing effect, followed by an increase in a sub-G1 (apoptotic) population after 24h. HIF1A-inhibition. i) Both compounds show a potent inhibition of HIF1A signaling in a cell based reporter assay (HRE-bla HCT-116) at EC50s of 1–25nM, whereas ii) at concentrations of 1 μ M, neither of the compounds shows an effect in assay systems monitoring the JAK/STAT, NFκB, PI3K/AKT/FOXO or Wnt/β-catenin-signaling pathways. iii) Kinase inhibition profiling showed no significant inhibition at 1μ M in two assays assessing 100 (Invitrogen) and 442 (Ambit) kinases, respectively. Pre-clinical pharmacology. Single dose exposure of 25 mg p.o. yields a maximum concentration of 1.1 μ M with a half life time of 3.6 hours (ELR510444) and 2.7 μ M and 6.6 h (ELR510552) in mice, respectively. The compounds are well-tolerated at levels that are significantly above the in vitro EC50 in all myeloma cell lines and primary samples tested. Conclusion. ELR510444 and ELR510552 are very active on all tested myeloma cell lines and primary myeloma cells without major impact on the bone marrow microenvironment, and show activity in two different mouse models. The compounds inhibit HIF1A-signaling and induce apoptosis via cell cycle arrest and tubulin depolymerization. Preclinical pharmacology data show favorable in vivo profiles with exposure levels in mice significantly higher than concentrations required for in vitro activity. Therefore, this novel class of compounds represents a promising weapon in the therapeutic arsenal against multiple myeloma entering a phase I/II trial within the next year. Disclosures: Leber: ELARA Pharmaceuticals GmbH: Employment. Janssen:ELARA Pharmaceuticals GmbH: Employment. Lewis:ELARA Pharmaceuticals GmbH: Employment. Schultes:ELARA Pharmaceuticals GmbH: Employment.

Description: Abstract 2942 Tumor-specific cytotoxic T cells are common in tumor patients, but ineffectively react against autologous tumor cells. Here, we demonstrate in multiple myeloma and breast cancer that human tumor cells escape recognition by tumor-specific CD8+ T cells through carcinoembryonic antigen-related cell adhesion molecule-6 (CEACAM-6) expression. We demonstrate for the first time CEACAM-6 expression in primary and established myeloma and examined the effects of altered CEACAM expression on cytotoxic T cell activity and cytokine secretion against myeloma and breast cancer cells in vitro —, and in vivo, using a xenotransplant mouse model. Cytotoxic T cells from multiple myeloma patients reacted against myeloma antigens presented by dendritic cells, but not against autologous myeloma cells, which expressed CEACAM6. Gene knockdown or blocking of CEACAM6 on myeloma cells restored CD8+ T-cell reactivity against malignant plasma cells. SiRNA-mediated CEACAM6 knockdown or inhibition by specific mAbs also restored cytokine secretion, cytotoxic activity, and antigen-specific lysis of CEACAM6-positive breast cancer cells. Moreover, CEACAM-6 inhibition was a prerequisite for efficient treatment of xenotransplanted breast tumors by adoptive T cell transfer. CEACAM6 thus plays an important role in inhibiting CD8+ T-cell responses against hematological and epithelial human tumors. Therapeutic targeting of CEACAM6 may be a promising strategy for improving cancer immunotherapy. Disclosures: No relevant conflicts of interest to declare.

Description: Introduction: Next generation sequencing of over 800 newly diagnosed multiple myeloma (NDMM) cases has established the mutational landscape and key cancer driver pathways. The mutational basis of relapse has not been systematically studied. Two previous studies (Keats et al.; Bolli et al.) identified 4 patterns of clonal evolution. Neither study included uniformly treated patients and looked at the impact of therapy on clonal structure at relapse. Understanding the mutational patterns underlying relapse and how they relate to specific therapies is crucial in order to improve MM outcomes, especially for high-risk (HR) MM. In this study we compare the clonal structure at presentation (PRES) and at relapse (REL), after exposure to Total Therapy (TT). Materials and Methods: We studied 33 pairs of tumor samples collected at PRES and REL. 9 patients were treated on TT2, 13 on TT3, 10 on TT4 and 1 on TT5-like regimen. Eleven patients had HR disease at PRES. DNA was extracted from CD138+ selected cells from random bone marrow aspirates. Germline controls were obtained from leukapheresis products. Whole exome sequencing libraries were prepared using the Agilent qXT kit and the Agilent SureSelect Clinical Research Exome kit with additional baits covering the Ig and MYC loci. All samples were sequenced on an Illumina HiSeq2500 to a median depth of 120x. Sequencing data were aligned to the Ensembl GRCh37/hg19 human reference using BWA. Somatic variants were called using MuTect. Translocations were identified using MANTA. Copy number variations were inferred using TITAN. Gene expression profiles (GEP), generated using the Affymetrix U133plus2 microarray, were available for all tumor samples. Nonnegative matrix factorization (NMF) was used to define mutation signatures. Results: The median time to progression was 30 months with a median follow up of 9.5 years. 22 cases achieved a complete remission (CR) or near CR. There were 11 cases of HR at PRES. Of the 22 cases with low risk (LR) MM, 7 relapsed with HR disease. There were on average 478 SNVs per sample at PRES and 422 at REL. All but 2 cases had evidence of new mutations at REL. There were no consistent patterns or number of mutation associated with REL or GEP-defined risk. Patients of the MF molecular subgroup had more mutations compared to other molecular subgroups (657 vs. 379) and were enriched for mutations with an APOBEC signature. We did not detect any mutation signature consistent with chemotherapy-induced alterations, providing evidence that TT itself does not cause additional mutations. Primary recurrent IgH translocations called by MANTA were confirmed by GEP data. A number of new translocations were identified , several only at REL. In particular we demonstrate a case with a newly acquired MYC translocation at relapse, indicating that it contributed to progression. We identified 5 patterns of clonal evolution (Figure 1): A) genetically distinct relapse in 3 patients, B) linear evolution in 8 patients, C) clonal selection in 9 patients, D) branching evolution in 11 patients, and E) stable clone(s) in 2 patients. Patterns A (distinct) and B (linear) were associated with low risk and longer survival, whereas patterns D (branching) and E (stable) were associated with high risk and shorter time to relapse and overall survival (Table 1). Conclusion: This is the first study to systematically analyze the pattern of clonal evolution using NGS in patients treated with combination chemotherapy and tandem ASCT. We identified 5 patterns of evolution, which correlate with survival. We identified 3 cases with a loss of the original clone and emergence of a new clone, suggesting high effectiveness of Total Therapy for those patients. The persistence of major clones despite multi agent chemotherapy in most other cases supports a concept of a tumor-initiating cell population that persist in a protective niche, for which new therapies are needed. Table 1. Pattern of Evolution GEP70 Pres.(high risk: ≥0.66) Proliferation Index Pres. GEP70 Rel.(high risk: ≥0.66) Proliferation Index Rel Mean OS Mean TTR A: distinct (n=3) -0.690 -3.34 -0.015 2.04 8.18 5.00 B: linear (n=8) -0.171 -0.34 0.618 9.22 5.70 4.05 C: selection (n=9) 0.366 3.20 0.569 6.97 3.95 2.64 D: branching (n=11) 0.710 5.17 1.173 11.15 3.84 2.21 E: stable (n=2) 1.532 7.42 1.124 2.54 0.96 0.35 Pres.: Presentation; Rel.: Relapse; OS: Overall Survival; TTR: Time to Relapse Figure 1. Patterns of Relapse Figure 1. Patterns of Relapse Disclosures Heuck: Foundation Medicine: Honoraria; Millenium: Other: Advisory Board; Janssen: Other: Advisory Board; Celgene: Consultancy; University of Arkansas for Medical Sciences: Employment. Weinhold:Janssen Cilag: Other: Advisory Board; University of Arkansas for Medical Sciences: Employment. Peterson:University of Arkansas for Medical Sciences: Employment. Bauer:University of Arkansas for Medical Sciences: Employment. Stein:University of Arkansas for Medical Sciences: Employment. Ashby:University of Arkansas for Medical Sciences: Employment. Chavan:University of Arkansas for Medical Sciences: Employment. Stephens:University of Arkansas for Medical Sciences: Employment. Johann:University of Arkansas for Medical Sciences: Employment. van Rhee:University of Arkansa for Medical Sciences: Employment. Waheed:University of Arkansas for Medical Sciences: Employment. Johnson:University of Arkansas for Medical Sciences: Employment. Zangari:University of Arkansas for Medical Sciences: Employment; Millennium: Research Funding; Onyx: Research Funding; Novartis: Research Funding. Matin:University of Arkansas for Medical Sciences: Employment. Petty:University of Arkansas for Medical Sciences: Employment. Yaccoby:University of Arkansas for Medical Sciences: Employment. Davies:University of Arkansas for Medical Sciences: Employment; Millenium: Consultancy; Janssen: Consultancy; Onyx: Consultancy; Celgene: Consultancy. Epstein:University of Arkansas for Medical Sciences: Employment. Barlogie:University of Arkansas for Medical Sciences: Employment. Morgan:Weismann Institute: Honoraria; MMRF: Honoraria; Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; University of Arkansas for Medical Sciences: Employment; CancerNet: Honoraria; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees.