Search

Purpose: This phase I/II study evaluated safety, efficacy, and pharmacokinetics of escalating, multiple doses of siltuximab, a chimeric anti-interleukin (IL)-6 monoclonal antibody derived from a new Chinese hamster ovary (CHO) cell line in patients with advanced/refractory solid tumors.Experimental Design: In the phase I dose-escalation cohorts, 20 patients with advanced/refractory solid tumors received siltuximab 2.8 or 5.5 mg/kg every 2 weeks or 11 or 15 mg/kg every 3 weeks intravenously (i.v.). In the phase I expansion (n = 24) and phase II cohorts (n = 40), patients with Kirsten rat sarcoma-2 (KRAS)-mutant tumors, ovarian, pancreatic, or anti-EGF receptor (EGFR) refractory/resistant non–small cell lung cancer (NSCLC), colorectal, or H&N cancer received 15 mg/kg every 3 weeks. The phase II primary efficacy endpoint was complete response, partial response, or stable disease >6 weeks.Results: Eighty-four patients (35 colorectal, 29 ovarian, 9 pancreatic, and 11 other) received a median of three (range, 1–45) cycles. One dose-limiting toxicity occurred at 5.5 mg/kg. Common grade ≥3 adverse events were hepatic function abnormalities (15%), physical health deterioration (12%), and fatigue (11%). Ten percent of patients had siltuximab-related grade ≥3 adverse events. Neutropenia (4%) was the only possibly related adverse event grade ≥3 reported in >1 patient. Serious adverse events were reported in 42%; most were related to underlying disease. The pharmacokinetic profile of CHO-derived siltuximab appears similar to the previous cell line. No objective responses occurred; 5 of 84 patients had stable disease >6 weeks. Hemoglobin increased ≥1.5 g/dL in 33 of 47 patients. At 11 and 15 mg/kg, completely sustained C-reactive protein suppression was observed.Conclusions: Siltuximab monotherapy appears to be well tolerated but without clinical activity in solid tumors, including ovarian and KRAS-mutant cancers. The recommended phase II doses were 11 and 15 mg/kg every 3 weeks. Clin Cancer Res; 20(8); 2192–204. ©2014 AACR.

PDF file - 99KB, Supplementary Methods: The supplemental material contains additional detail on the pharmacokinetic and pharmacodynamic methods used during the study as well as a summary table of safety events and a figure detailing patient disposition. Supplemental Table 1: Summary of safety events in all study cohorts.

Figure S1 - PDF file 23K, Mean serum siltuximab concentration following the first dose of 12 mg/kg by disease type in patients evaluable for pharmacokinetics analysis in cohorts 3, 5, and 6. Abbreviations: CD, Castleman's disease; Inf, infusion; MM, multiple myeloma; NHL, non-Hodgkin's lymphoma

Supplementary Methods - PDF file 88K, Supplementary methods for pharmacokinetic analyses and pharmacodynamic analyses

PDF file - 25KB, Supplementary Figure S1. Patient disposition: AE, adverse event. KRAS, Kirsten rat sarcoma-2. PD, progressive disease. q2w, every 2 weeks. q3w, every 3 weeks.

Purpose: Originally isolated on the basis of its ability to induce p53, serdemetan showed potent activity in various preclinical models, inducing S-phase arrest and apoptosis in TP53 wild-type and mutant tumors. This study evaluated the safety and tolerability of serdemetan, determined the pharmacokinetic and pharmacodynamic profiles, and identified a recommended phase II dose.Patients and Methods: Patients (71) with refractory solid tumors were allocated to dose-escalating cohorts (3+3 patients each) and received oral serdemetan once daily in 21-day cycles to determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLT). Plasma was collected for pharmacokinetic analyses. Paired baseline and on-treatment skin and tumor biopsies were done; blood samples were collected for pharmacodynamic analyses, including p53 and macrophage inhibitory cytokine-1 induction.Results: The MTD of serdemetan was determined to be 350 mg once daily. During this study, grade 3 QTc prolongation was the most common DLT and nausea (66.2%) was the most frequent treatment-emergent adverse event. Serdemetan was rapidly absorbed after oral administration and exhibited dose-proportional pharmacokinetics. At steady state, mean maximum plasma concentration (Cmax) was 2,330 ng/mL and mean area under plasma concentration curve (AUC0–24h) was 43.0 μg.h/mL, with serdemetan 300 mg/d. There was a dose- and exposure-dependent p53 induction. One patient with breast cancer showed a partial response; 22 (38.6%) patients had stable disease.Conclusions: Serdemetan treatment was associated with p53 induction in both tumor and surrogate tissue pharmacodynamic studies and modest clinical activity. Although serdemetan was well tolerated with dose-proportional pharmacokinetics, exposure-related QTc liability was observed. Clin Cancer Res; 17(19); 6313–21. ©2011 AACR.

Purpose: To evaluate the safety and pharmacokinetics of siltuximab, an anti–interleukin-6 chimeric monoclonal antibody (mAb) in patients with B-cell non-Hodgkin lymphoma (NHL), multiple myeloma, or Castleman disease.Experimental Design: In an open-label, dose-finding, 7 cohort, phase I study, patients with NHL, multiple myeloma, or symptomatic Castleman disease received siltuximab 3, 6, 9, or 12 mg/kg weekly, every 2 weeks, or every 3 weeks. Response was assessed in all disease types. Clinical benefit response (CBR; composite of hemoglobin, fatigue, anorexia, fever/night sweats, weight, largest lymph node size) was also evaluated in Castleman disease.Results: Sixty-seven patients received a median of 16 siltuximab doses for a median of 8.5 (maximum 60.5) months; 29 were treated 1 year or longer. There was no dose-limiting toxicity, antibodies to siltuximab, or apparent dose–toxicity relationship. The most frequently reported possible drug-related adverse events were thrombocytopenia (25%), hypertriglyceridemia (19%), neutropenia (19%), leukopenia (18%), hypercholesterolemia (15%), and anemia (10%). None of these events led to dose delay/discontinuation except for neutropenia and thrombocytopenia (n = 1 each). No treatment-related deaths occurred. C-reactive protein (CRP) suppression was most pronounced at 12 mg/kg every 3 weeks. Mean terminal-phase half-life of siltuximab ranged 17.73 to 20.64 days. Thirty-two of 37 (86%) patients with Castleman disease improved in 1 or more CBR component; 12 of 36 evaluable Castleman disease patients had radiologic response [complete response (CR), n = 1; partial response (PR), n = 11], including 8 of 19 treated with 12 mg/kg; 2 of 14 (14%) evaluable NHL patients had PR; 2 of 13 (15%) patients with multiple myeloma had CR.Conclusion: No dose-related or cumulative toxicity was apparent across all disease indications. A dose of 12 mg/kg every 3 weeks was recommended on the basis of the high response rates in Castleman disease and the sustained CRP suppression. Randomized studies are ongoing in Castleman disease and multiple myeloma. Clin Cancer Res; 19(13); 3659–70. ©2013 AACR.

Supplementary Table S1 - PDF file Percent change from baseline in serum C-reactive protein concentration (mg/L) in Cohort 7

The Sudden Oak Death (SOD) Blitzes consist of yearly surveys led by citizen scientists designed to map the distribution of Phytophthora ramorum, cause of the forest disease called SOD, across northern California. During the 2017 Santa Cruz County SOD Blitz, six rare or endangered Arctostaphylos (manzanita) species were found to be possibly symptomatic for the first time. Symptoms included branch cankers and associated canopy mortality, and affected multiple individuals per species. Isolates of P. ramorum were obtained from each of the six species and, through a 30-day-long inoculation experiment on live plants, Koch’s postulates were completed for each one of them, conclusively determining that they all are hosts of this pathogen. Two additional manzanita species were later found to be apparently symptomatic in Marin County. Inoculations on detached branches using an isolate of P. ramorum obtained from one of the six rare species from Santa Cruz County were successful, suggesting that these two species may also be hosts of P. ramorum. Detached leaves of all eight species were also successfully inoculated at the University of California-Berkeley in fall 2018 and then again in spring 2019. In these cases, the same isolate was used for all inoculations, in order to obtain information on the comparative susceptibility of the eight species in question. Both branch and leaf inoculations identified significant interspecific differences in susceptibility. The production of sporangia was low on all species but it was not zero, suggesting that sporulation may cause within-plant and limited across-plant contagion, especially in rainy years.

e16297 Background: KRAS mutations are common in pancreatic ductal adenocarcinoma (PDAC). While 90% of PDAC tumors display activating mutations in KRAS, only ̃2% are G12C, a specific KRAS mutation targeted by inhibitors such as sotorasib or adagrasib. MEK, which lies downstream of KRAS, is an attractive target to more broadly counteract elevated MAPK signaling regardless of the upstream mutation. However, FDA registered MEK inhibitors are prone to pathway reactivation events, which limit their utility in RAS mutant disease and necessitate chronic pathway inhibition that contributes to on-target toxicity. In contrast, IMM-1-104 is a novel, allosteric dual-MEK inhibitor designed to block pathway reactivation by disrupting phosphorylation of both MEK and ERK and has a short plasma drug half-life. These characteristics enable IMM-1-104 to drive deep cyclic MAPK pathway inhibition, with the potential to inhibit tumors driven by diverse RAS mutations. Methods: IMM-1-104 was tested head-to-head versus sotorasib, adagrasib, selumetinib and binimetinib in a series of preclinical models to characterize differential activity of each compound against tumors driven by diverse KRAS mutations. Cell-based 2D biochemical and 3D growth assays were performed across nine PDAC models, and the Capan-2 PDAC xenograft animal model was used to evaluate single agent activity of IMM-1-104 (75, 100, 150 mg/kg BID p.o. or 150 mg/kg QD p.o.) vs. sotorasib or adagrasib (30 and 100 mg/kg QD p.o. each) for 21 days treatment after tumors had reached volumes of 150 to 200 mm3. Results: IMM-1-104 alone led to reductions in both pERK and pMEK across all 9 PDAC models tested (KRAS status shown), including Hs766T (Q61H), MIA PaCa-2 (G12C), Capan-2 (G12V), AsPC-1 (G12D), CFPAC-1 (G12V), BxPC3 (wild type), Panc 10.05 (G12D), Capan-1 (G12V) and PSN1 (G12R). A head-to-head comparison in vivo demonstrated no Tumor Growth Inhibition (TGI) by sotorasib and adagrasib in KRAS-G12V mutant Capan-2 PDAC tumors, while IMM-1-104 prompted TGIs of 49 to 84% across all doses and schedules tested. Conclusions: Despite multiple clinical studies, including Phase 2 studies for the MEK inhibitors trametinib and selumetinib, limited progress has been made in PDAC treatment since FOLFIRINOX’s approval in 2011. The Phase 2 KRYSTAL-1 and Phase 1/2 CodeBreaK 100 studies recently reported promising activity in KRAS-G12C PDAC, suggesting an opportunity for disruption of KRAS addiction. IMM-1-104 and sotorasib previously demonstrated comparable tumor regressions in vivo in a KRAS G12C mutant model, MIA PaCa-2 (2021 EORTC). Examining the broader activity of IMM-1-104 across 9 PDAC tumor models yielded data suggesting that deep, cyclic MEK inhibition by IMM-1-104 has the potential to offer a unique advantage over first generation MEK inhibitors and KRAS-G12C inhibitors in PDAC by inhibiting tumors driven by a broader range of more common KRAS mutations.

e15084 Background: Elevated RAS-RAF-MEK-ERK (MAPK pathway) signaling is observed in over half of all solid human tumors, and mutations in RAS or RAF account for a large fraction. Given MEK’s unique position in the MAPK cascade, it remains an attractive target in cancer. However, FDA-registered MEK inhibitors are susceptible to pathway reactivation events that limit their use to RAF mutant disease and cause on-target toxicities stemming from chronic target engagement. IMM-1-104 is a novel, allosteric dual-MEK inhibitor designed for better applicability to RAS mutant tumors by preventing MEK reactivation. Endowed with a short plasma half-life, IMM-1-104 promotes deep cyclic inhibition with a near-zero drug trough, affording normal cells a chance to recover between doses. Methods: We characterized IMM-1-104’s pharmacologic activity across 52 tumor cell lines that spanned 11 distinct tumor types in a humanized, ECM-based 3D tumor growth assay (3D-TGA). The 3D-TGA has better predicted in vivo tumor responses versus 2D culture and more accurately reflects human tumor biology. Tumor models were categorized based on in vivo drug PK limits as sensitive to IMM-1-104 (EC50 < 1uM), intermediate (1uM≤EC50≤10uM and ≥25% inhibition at 10uM) or resistant otherwise. Models were evaluated by whole exome sequencing, along with RNA sequencing in the 3D context, to profile determinants of sensitivity and resistance and to prioritize patient populations most likely to respond to IMM-1-104. Results: Models sensitive to IMM-1-104 were enriched for MAPK driver mutations, consistent with pathway addiction. We reasoned that activation of parallel compensatory pathways that can reduce reliance on MAPK signaling may increase the likelihood of resistance to IMM-1-104. Pathways and genes suspected of contributing to resistance helped refine signatures based on 3D-TGA outcome data. Models with a MAPK driver mutation and compensatory mutations such as PIK3CA or PTEN deletion were more likely to show intermediate response than those with a greater addiction to MAPK drivers. Models lacking a clear MAPK driver mutation but harboring other putative resistance alterations were more likely to be resistant in the 3D-TGA. Conclusions: To better understand the relevance of tumor model responses in the 3D-TGA relative to RAS mutant patient populations, we computationally compared tumor model data to patient somatic alterations, identified in the public resource GENIE, which has cataloged the molecular profiles of over 100,000 cancer patients. Based on model-to-patient molecular mapping, we identified biomarker-defined subsets of sensitive KRAS mutant lung and colorectal models. The most broadly sensitive patient-aligned models in the 3D assay were KRAS mutant pancreatic cancer and NRAS mutant melanoma patients, supporting the inclusion of such patients in planned clinical studies of IMM-1-104.

The Sudden Oak Death (SOD) Blitzes consist of yearly surveys led by citizen scientists designed to map the distribution of

Background: The cell of origin (COO) in diffuse large B-cell lymphoma (DLBCL) has prognostic importance. While the COO was originally classified into germinal center B-cell (GCB) or activated B-cell (ABC) subtypes by microarray analysis, routine use was not practical. Immunohistochemistry (IHC)–based methods are widely used with varying results due to lack of standardization. Several classification methods have been developed recently; understanding the concordance between these and existing methods is essential to their practical application. Therefore, we evaluated concordance between 3 commercial assays: a standardized Hans-based IHC method and 2 gene expression profiling (GEP) methods and compared these to the accepted microarray classification.Methods: 137 DLBCL-confirmed tumor samples were evaluated using a standardized Hans-based IHC method for GCB or non-GCB subtype, by a published microarray-based assay, a digital gene expression-based Lymphoma Subtyping Test (LST) and a next-generation sequencing-based assay (EdgeSeq COO). Subtype calls from the 3 GEP methods were harmonized to “GCB” or “non-GCB” and assessed for concordance.Results: Concordance between the Hans-based IHC assay and the microarray-based assay, LST assay and EdgeSeq assay was 79.6% (N=137), 80.0% (N=125) and 78.2% (N=64), respectively; the positive percent agreement (PPA) in non-GCB was 88.9%, 87.0% and 78.1%, respectively. Concordance for the Hans-based IHC assay versus GEP methods was especially high for direct GCB calls (91.0%, 88.3% and 78.1% for microarray, LST and EdgeSeq COO methods, respectively). The newly developed GEP assays performed well against the microarray GEP method, against which they were calibrated (concordance 93.7% and 87.5% and PPA 94.3% and 92.9%, respectively, for LST and EdgeSeq COO).Conclusion: These results demonstrated good consistency between various platforms for stratification of DLBCL into COO subtype classifications. Application of a standardized Hans-based IHC assay offers a robust, rapid and easily accessible platform to classify DLBCL into prognostically important subtypes.

Purpose: Siltuximab (IL6 antibody) is approved for the treatment of multicentric Castleman disease (MCD). Effects of IL6 inhibition on the inflammatory milieu accompanying MCD have not been characterized. Experimental Design: Trends in inflammatory- and anemia-associated markers, measured over the course of a placebo-controlled study of siltuximab (11 mg/kg q3w) in patients with MCD (n = 79), were characterized. Results: Baseline IL6 and C-reactive protein (CRP) levels were significantly correlated (r = 0.708; P < 0.0001). CRP levels decreased (median, 92%) by cycle 1 day 8 (C1D8), remaining suppressed during siltuximab treatment while remaining stable in the placebo group. There were no associations between baseline CRP or IL6 and MCD symptom burden, histologic subtype, ethnicity, maximum CRP decrease, and response parameters. A hemoglobin response (change ≥ 15 g/L at week 13) was observed with siltuximab (61%; P = 0.0002). Median hepcidin decrease from baseline at C1D8 with siltuximab was 47% versus median 11% increase with placebo. Maximum post-baseline changes in hepcidin levels among siltuximab recipients were correlated with maximum changes for hemoglobin (r = −0.395; P = 0.00607), total iron-binding capacity (TIBC; r = −0.354; P = 0.01694), and ferritin (r = 0.599; P = 0.0001). Greater median changes from baseline in ferritin, hemoglobin, and TIBC were observed in anemic siltuximab-treated patients. Conclusions: IL6 neutralization with siltuximab resulted in sustained CRP suppression and improvement of anemia, in part, by hepcidin pathway inhibition. Clin Cancer Res; 21(19); 4294–304. ©2015 AACR.

Aim Interleukin-6 (IL-6), a multifunctional cytokine, exists in several forms ranging from a low molecular weight (MW 20–30 kDa) non-complexed form to high MW (200–450 kDa), complexes. Accurate baseline IL-6 assessment is pivotal to understand clinical responses to IL-6-targeted treatments. Existing assays measure only the low MW, non-complexed IL-6 form. The present work aimed to develop a validated assay to measure accurately total IL-6 (complexed and non-complexed) in serum or plasma as matrix in a high throughput and easily standardized format for clinical testing. Methods Commercial capture and detection antibodies were screened against humanized IL-6 and evaluated in an enzyme-linked immunosorbent assay format. The best antibody combinations were screened to identify an antibody pair that gave minimum background and maximum recovery of IL-6 in the presence of 100% serum matrix. A plate-based total IL-6 assay was developed and transferred to the Meso Scale Discovery (MSD) platform for large scale clinical testing. Results The top-performing antibody pair from 36 capture and four detection candidates was validated on the MSD platform. The lower limit of quantification in human serum samples (n = 6) was 9.77 pg l–1, recovery ranged from 93.13–113.27%, the overall pooled coefficients of variation were 20.12% (inter-assay) and 8.67% (intra-assay). High MW forms of IL-6, in size fractionated serum samples from myelodysplastic syndrome and rheumatoid arthritis patients, were detected by the assay but not by a commercial kit. Conclusion This novel panoptic (sees all forms) IL-6 MSD assay that measures both high and low MW forms may have clinical utility.

Purpose: This phase I/II study evaluated safety, efficacy, and pharmacokinetics of escalating, multiple doses of siltuximab, a chimeric anti-interleukin (IL)-6 monoclonal antibody derived from a new Chinese hamster ovary (CHO) cell line in patients with advanced/refractory solid tumors. Experimental Design: In the phase I dose-escalation cohorts, 20 patients with advanced/refractory solid tumors received siltuximab 2.8 or 5.5 mg/kg every 2 weeks or 11 or 15 mg/kg every 3 weeks intravenously (i.v.). In the phase I expansion (n = 24) and phase II cohorts (n = 40), patients with Kirsten rat sarcoma-2 (KRAS)-mutant tumors, ovarian, pancreatic, or anti-EGF receptor (EGFR) refractory/resistant non–small cell lung cancer (NSCLC), colorectal, or H&N cancer received 15 mg/kg every 3 weeks. The phase II primary efficacy endpoint was complete response, partial response, or stable disease >6 weeks. Results: Eighty-four patients (35 colorectal, 29 ovarian, 9 pancreatic, and 11 other) received a median of three (range, 1–45) cycles. One dose-limiting toxicity occurred at 5.5 mg/kg. Common grade ≥3 adverse events were hepatic function abnormalities (15%), physical health deterioration (12%), and fatigue (11%). Ten percent of patients had siltuximab-related grade ≥3 adverse events. Neutropenia (4%) was the only possibly related adverse event grade ≥3 reported in >1 patient. Serious adverse events were reported in 42%; most were related to underlying disease. The pharmacokinetic profile of CHO-derived siltuximab appears similar to the previous cell line. No objective responses occurred; 5 of 84 patients had stable disease >6 weeks. Hemoglobin increased ≥1.5 g/dL in 33 of 47 patients. At 11 and 15 mg/kg, completely sustained C-reactive protein suppression was observed. Conclusions: Siltuximab monotherapy appears to be well tolerated but without clinical activity in solid tumors, including ovarian and KRAS-mutant cancers. The recommended phase II doses were 11 and 15 mg/kg every 3 weeks. Clin Cancer Res; 20(8); 2192–204. ©2014 AACR.

Purpose: To evaluate the safety and pharmacokinetics of siltuximab, an anti–interleukin-6 chimeric monoclonal antibody (mAb) in patients with B-cell non-Hodgkin lymphoma (NHL), multiple myeloma, or Castleman disease. Experimental Design: In an open-label, dose-finding, 7 cohort, phase I study, patients with NHL, multiple myeloma, or symptomatic Castleman disease received siltuximab 3, 6, 9, or 12 mg/kg weekly, every 2 weeks, or every 3 weeks. Response was assessed in all disease types. Clinical benefit response (CBR; composite of hemoglobin, fatigue, anorexia, fever/night sweats, weight, largest lymph node size) was also evaluated in Castleman disease. Results: Sixty-seven patients received a median of 16 siltuximab doses for a median of 8.5 (maximum 60.5) months; 29 were treated 1 year or longer. There was no dose-limiting toxicity, antibodies to siltuximab, or apparent dose–toxicity relationship. The most frequently reported possible drug-related adverse events were thrombocytopenia (25%), hypertriglyceridemia (19%), neutropenia (19%), leukopenia (18%), hypercholesterolemia (15%), and anemia (10%). None of these events led to dose delay/discontinuation except for neutropenia and thrombocytopenia (n = 1 each). No treatment-related deaths occurred. C-reactive protein (CRP) suppression was most pronounced at 12 mg/kg every 3 weeks. Mean terminal-phase half-life of siltuximab ranged 17.73 to 20.64 days. Thirty-two of 37 (86%) patients with Castleman disease improved in 1 or more CBR component; 12 of 36 evaluable Castleman disease patients had radiologic response [complete response (CR), n = 1; partial response (PR), n = 11], including 8 of 19 treated with 12 mg/kg; 2 of 14 (14%) evaluable NHL patients had PR; 2 of 13 (15%) patients with multiple myeloma had CR. Conclusion: No dose-related or cumulative toxicity was apparent across all disease indications. A dose of 12 mg/kg every 3 weeks was recommended on the basis of the high response rates in Castleman disease and the sustained CRP suppression. Randomized studies are ongoing in Castleman disease and multiple myeloma. Clin Cancer Res; 19(13); 3659–70. ©2013 AACR.

For drug discovery, cell-based assays are becoming increasingly complex to mimic more realistically the nature of biological processes and their diversifications in diseases. Multicellular co-cultures embedded in a three-dimensional (3D) matrix have been explored in oncology to more closely approximate the physiology of the human tumor microenvironment. High-content analysis is the ideal technology to characterize these complex biological systems, although running such complex assays at higher throughput is a major endeavor. Here, we report on adapting a 3D tumor co-culture growth assay to automated microscopy, and we compare various imaging platforms (confocal vs. nonconfocal) with correlating automated image analysis solutions to identify optimal conditions and settings for future larger scaled screening campaigns. The optimized protocol has been validated in repeated runs where established anticancer drugs have been evaluated for performance in this innovative assay.

Interleukin-6 (IL6) plays a central role in multiple myeloma pathogenesis and confers resistance to corticosteroid-induced apoptosis. We therefore evaluated the efficacy and safety of siltuximab, an anti-IL6 monoclonal antibody, alone and in combination with dexamethasone, for patients with relapsed or refractory multiple myeloma who had ≥ 2 prior lines of therapy, one of which had to be bortezomib-based. Fourteen initial patients received siltuximab alone, 10 of whom had dexamethasone added for suboptimal response; 39 subsequent patients were treated with concurrent siltuximab and dexamethasone. Patients received a median of four prior lines of therapy, 83% were relapsed and refractory, and 70% refractory to their last dexamethasone-containing regimen. Suppression of serum C-reactive protein levels, a surrogate marker of IL6 inhibition, was demonstrated. There were no responses to siltuximab but combination therapy yielded a partial (17%) + minimal (6%) response rate of 23%, with responses seen in dexamethasone-refractory disease. The median time to progression, progression-free survival and overall survival for combination therapy was 4.4, 3.7 and 20.4 months respectively. Haematological toxicity was common but manageable. Infections occurred in 57% of combination-treated patients, including ≥ grade 3 infections in 18%. Further study of siltuximab in modern corticosteroid-containing myeloma regimens is warranted, with special attention to infection-related toxicity.

Research on potential diversionary uses of military force continues to generate widespread scholarly attention. New measures, novel databases, and an increasing internationalization of this research examine the kinds of targets an American president may strike. Yet in many respects, Levy's insight on research of diversionary military action(s), that quantitative research approaches fail to capture the decision-making dynamics involved in a military action, has generally held true. Current analysts still struggle to develop a consensus on the conditions that help explain a diversionary military action, or whether such military actions ever even occur. Using a diversionary-war model created from previous case-study analyses this research examines American military actions in Grenada in 1983 and Iraq in 1996 to determine whether or not these strikes appear to be diversionary in nature. Our model also employs previous research on diversionary military action to assist in the selection of American military act...

Purpose: Originally isolated on the basis of its ability to induce p53, serdemetan showed potent activity in various preclinical models, inducing S-phase arrest and apoptosis in TP53 wild-type and mutant tumors. This study evaluated the safety and tolerability of serdemetan, determined the pharmacokinetic and pharmacodynamic profiles, and identified a recommended phase II dose. Patients and Methods: Patients (71) with refractory solid tumors were allocated to dose-escalating cohorts (3+3 patients each) and received oral serdemetan once daily in 21-day cycles to determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLT). Plasma was collected for pharmacokinetic analyses. Paired baseline and on-treatment skin and tumor biopsies were done; blood samples were collected for pharmacodynamic analyses, including p53 and macrophage inhibitory cytokine-1 induction. Results: The MTD of serdemetan was determined to be 350 mg once daily. During this study, grade 3 QTc prolongation was the most common DLT and nausea (66.2%) was the most frequent treatment-emergent adverse event. Serdemetan was rapidly absorbed after oral administration and exhibited dose-proportional pharmacokinetics. At steady state, mean maximum plasma concentration (Cmax) was 2,330 ng/mL and mean area under plasma concentration curve (AUC0–24h) was 43.0 μg.h/mL, with serdemetan 300 mg/d. There was a dose- and exposure-dependent p53 induction. One patient with breast cancer showed a partial response; 22 (38.6%) patients had stable disease. Conclusions: Serdemetan treatment was associated with p53 induction in both tumor and surrogate tissue pharmacodynamic studies and modest clinical activity. Although serdemetan was well tolerated with dose-proportional pharmacokinetics, exposure-related QTc liability was observed. Clin Cancer Res; 17(19); 6313–21. ©2011 AACR.

Wnt/β-catenin signaling is central to bone development and homeostasis in adulthood and its deregulation is associated with bone pathologies. Dickkopf-1 (DKK1), a soluble inhibitor of Wnt/β-catenin signaling required for embryonic head development, regulates Wnt signaling by binding to the Wnt coreceptor lipoprotein-related protein-5 (LRP5)/Arrow. LRP5 mutations causing high bone mass syndromes disrupt DKK1-mediated regulation of LRP5. Forced overexpression of Dkk1 in osteoblasts causes osteopenia, disruption of the hematopoietic stem cell (HSC) niche, and defects in HSC function. Dkk1 also inhibits fracture repair. Studies suggest that DKK1 activation in osteoblasts is the underlying cause of glucocorticoid- and estrogen deficiency–mediated osteoporosis, and at least partially underlies the teratogenic effects of thalidomide on limb development. DKK1 induces proliferation of mesenchymal stem cells (MSC) in vitro and may play a role in the development of high-grade undifferentiated pleomorphic sarcomas derived from MSC and osteosarcomas. DKK1 has been implicated in causing erosive arthritis, the osteolytic phenotypes of multiple myeloma and metastatic breast cancer, and osteoblastic metastases of prostate cancer. Preclinical studies have shown that neutralizing DKK1/Dkk1 and/or enhancing Wnt/β-catenin signaling may prove effective in treating bone pathologies. Here, we review the rapidly growing body of literature defining a pivotal role for DKK1 in bone health and disease.

Studies support the importance of microRNAs in physiological and pathological processes. Here we describe the regulation and function of miR-29 in myogenesis and rhabdomyosarcoma (RMS). Results demonstrate that in myoblasts, miR-29 is repressed by NF-kappaB acting through YY1 and the Polycomb group. During myogenesis, NF-kappaB and YY1 downregulation causes derepression of miR-29, which in turn accelerates differentiation by targeting its repressor YY1. However, in RMS cells and primary tumors that possess impaired differentiation, miR-29 is epigenetically silenced by an activated NF-kappaB-YY1 pathway. Reconstitution of miR-29 in RMS in mice inhibits tumor growth and stimulates differentiation, suggesting that miR-29 acts as a tumor suppressor through its promyogenic function. Together, these results identify a NF-kappaB-YY1-miR-29 regulatory circuit whose disruption may contribute to RMS.

Common sites of breast cancer metastasis include the lung, liver, and bone, and of these secondary metastatic sites, estrogen receptor α (ERα)–positive breast cancer often favors bone. Within secondary organs, cancer cells would predictably encounter tissue-specific fibroblasts or their soluble factors, yet our understanding of how tissue-specific fibroblasts directly affect cancer cell growth rates and survival remains largely unknown. Therefore, we tested the hypothesis that mesenchymal fibroblasts isolated from common sites of breast cancer metastasis provide a more favorable microenvironment with respect to tumor growth rates. We found a direct correlation between the ability of breast, lung, and bone fibroblasts to enhance ERα-positive breast cancer cell growth and the level of soluble interleukin-6 (IL-6) produced by each organ-specific fibroblast, and fibroblast-mediated growth enhancement was inhibited by the removal or inhibition of IL-6. Interestingly, mice coinjected with MCF-7 breast tumor cells and senescent skin fibroblasts, which secrete IL-6, developed tumors, whereas mice coinjected with presenescent skin fibroblasts that produce little to no IL-6 failed to form xenograft tumors. We subsequently determined that IL-6 promoted growth and invasion of breast cancer cells through signal transducer and activator of transcription 3–dependent up-regulation of Notch-3, Jagged-1, and carbonic anhydrase IX. These data suggest that tissue-specific fibroblasts and the factors they produce can promote breast cancer disease progression and may represent attractive targets for development of new therapeutics. [Cancer Res 2008;68(21):9087–95]

Recent progress in the research of mesenchymal stromal cells/multipotent stromal cells (MSC) has revealed numerous beneficial innate characteristics, suggesting potential value in an array of cellular therapies. MSC are easily isolated from bone marrow (BM), fat and other tissues, and are readily propagated in vitro. Transplanted/injected MSC have been shown to migrate to a variety of organs and tissues; however, sites of inflammation and pathology elicit enhanced MSC homing for tissue remodeling and repair. Tumors utilize many of the same inflammatory mediators uncovered in wound healing and likewise provide a site for preferential MSC homing. Although incorporation into the tumor microenvironment is apparent, the role of recruited MSC in the tumor microenvironment remains unclear. Some published studies have shown enhancement of tumor growth and development, perhaps through immunomodulatory and pro-angiogenic properties, while others have shown no apparent effect or have demonstrated inhibition of tumor growth and extended survival. This controversy remains at the forefront as clinical applications of MSC commence in anti-tumor therapies as well as as adjuncts to stem cell transplantation and in ameliorating graft-versus-host disease. Careful analysis of past studies and thoughtful design of future experiments will help to resolve the discrepancies in the field and lead to clinical utility of MSC in disease treatment. This review highlights the current theories of the role of MSC in tumors and explores current controversies.

Recent evidence suggests that mesenchymal stem cells (MSC) selectively home to tumors, where they contribute to the formation of tumor-associated stroma. This effect can be opposed by genetically modifying MSC to produce high levels of anti-cancer agents that blunt tumor growth kinetics and inhibit the growth of tumors in situ. In this review article, we describe the biological properties of MSC within the tumor microenvironment and discuss the potential use of MSC and other bone marrow-derived cell populations as delivery vehicles for antitumor proteins.

Bone is the primary anatomical site of breast cancer metastasis, and bone metastasis is associated with increased morbidity and mortality. Mesenchymal stem cells (MSC) are a predominant fibroblast cell population within the bone marrow, and metastatic breast cancer cells that seed within bone would predictably encounter MSC or their soluble factors. Therefore, we examined the impact of primary human MSC on a panel of estrogen receptor-alpha (ERalpha)-positive (MCF-7, T47D, BT474, and ZR-75-1) and ERalpha-negative (MDA-MB-231 and MDA-MB-468) human breast tumor cell lines. All ERalpha-positive breast tumor cell lines displayed low basal activation of signal transducer and activator of transcription 3 (STAT3) until exposed to MSC, which induced chronic phosphorylation of STAT3 on tyrosine-705. Paracrine IL-6 was found to be the principal mediator of STAT3 phosphorylation in coculture studies, and MSC induction of STAT3 phosphorylation was lost when IL-6 was depleted from MSC conditioned media or the IL-6 receptor was blocked on tumor cells. Enhanced tumor cell growth rates were observed in the ERalpha-positive mammary tumor cell line MCF-7 after paracrine and autocrine IL-6 exposure, where MCF-7 growth rates were enhanced by >2-fold when cocultured with MSC in vitro and even more pronounced in vivo with autocrine IL-6 production.

The activation of signal transducer and activator of transcription 3 (Stat3) has been implicated in the oncogenesis of cancer and is regarded as a novel target for cancer therapy. Stat3 is classified as a proto-oncogene, because an activated form of Stat3 can mediate oncogenic transformation in cultured cells and tumour formation in nude mice. The constitutive activation of Stat3 has been frequently detected in various types of human cancers. However, the constitutive activation of Stat3 in endometrial and cervical cancers has not been studied. We examined tyrosine phosphorylation of Stat3 (activated form of Stat3) in multiple endometrial and cervical cancer tissues using tissue microarray slides as well as cancer cell lines to explore the possible activation of Stat3. Our results indicated that elevated phosphorylation of Stat3 was detected in cervical and endometrial cancer cell lines. Our results also showed that elevated levels of phosphorylation of Stat3 protein were detected in the endometrial and cervical cancer specimens. This is the first study to demonstrate that Stat3 is activated in human endometrial and cervical cancer tissues. Immunohistochemical staining showed that activated Stat3 is associated with increased expression of downstream antiapoptotic genes, Bcl-xL, survivin, and Mcl-1 in these tissues. Expression of a dominant-negative Stat3 mutant using adenovirus-mediated gene transfer inhibited cell growth and induced apoptosis in HeLa and SiHa cervical cancer cell lines expressing elevated levels of Stat3 phosphorylation. Further, a JAK/Stat3 small molecular inhibitor, JSI-124, induced apoptosis more selectively in HeLa and SiHa cancer cell lines than Ishikawa cell line without elevated levels of Stat3 phosphorylation. These results indicate that Stat3 is activated in human endometrial and cervical cancers and the inhibition of constitutive Stat3 signaling may be an effective target for cancer intervention in these two cancers.

Background: Survivin is proposed to play a central role in the progression and resistance to therapy of diverse tumour types. High levels of this molecule in tumour cells also correlate with loss of the TP53 tumour suppressor gene, suggesting a molecular connection between TP53 loss and transcriptional induction of Survivin. Patients with TP53 germline mutations, such as those with Li-Fraumeni syndrome, are particularly susceptible to sarcomas, including rhabdomyosarcomas. Our study aimed to identify rhabdomyosarcoma tumours that express Survivin, in order to test novel Survivin-targeted therapies in these tumours. Methods: Tumour microarray slides composed of 63 primary rhabdomyosarcoma tumours were stained with a polyclonal antibody to Survivin to identify tumours expressing Survivin. Subcutaneous tumours were then established in NOD/SCID mice using RH30 red cells, a red fluorescent clone of the RH30 human alveolar rhabdomyosarcoma cell line. Tumours were treated by hydrodynamic injection with a cocktail of Survivin-shRNA-encoding plasmids for a period of 2 weeks. Results: Over 80% of primary rhabdomyosarcoma tumours expressed Survivin. Treatment of rhabdomyosarcoma xenografts showed greater than 70% reduction in growth when compared with control injected tumours at study completion (average tumour sizes: 1683 v 304 mm 3 , p Conclusions: Our findings support a role for Survivin in rhabdomyosarcoma biology and provide preliminary evidence for the therapeutic use of Survivin-targeted RNA interference for human tumours that express high levels of this molecule.

Several laboratories have documented the necessity for direct contact of lymphoid and myeloid leukemic cells with bone marrow stromal cells for optimal survival. Subsequent studies have identified various stromal cell adhesion molecules and soluble factors that facilitate survival through leukemic cell anti-apoptotic signal transduction pathways. This report provides an overview of enhanced leukemic cell survival through adhesive interactions with bone marrow expressed molecules. In addition, we describe the establishment of cloned murine stromal cell lines engineered to constitutively express human VCAM-1 protein on their surface. These stromal cell lines will be useful in studies aimed at better understanding the specific contribution of VCAM-1: VLA-4 signaling in maintenance of residual leukemic disease.

Bcl-2 is the major anti-apoptotic protein evaluated in studies aimed at understanding programmed cell death. Recent work suggests that the biological activity of Bcl-2 is modulated by proteolytic cleavage, with a 23 kDa cleaved Bcl-2 product having pro-apoptotic activity. In the current study we evaluated the effect of chemotherapy on Bcl-2 cleavage in B lineage leukemic cell lines. JM-1, SUP-B 15 and RS4 leukemic cell lines cleaved Bcl-2 to its 23 kDa form when exposed to the chemotherapeutic agents 1-beta-D-arabinofuranosyl-cytosine (Ara-C) or etoposide (VP-16). Chemotherapy induced Bcl-2 cleavage was blunted by inhibition of caspase activity. Co-culture of leukemic cells with bone marrow stromal cells during chemotherapy exposure resulted in reduced levels of 23 kDa Bcl-2 protein. These observations suggest that the bone marrow microenvironment may contribute to maintenance of residual leukemic disease during treatment by reducing generation of pro-apoptotic 23 kDa Bcl-2.

The Community of Writers was found in 1969, with its first writing workshop session in 1970. In those days, the prose and poetry writers were together in Squaw Valley. In the mid-1980s, the Poetry ...

With a 7% likelihood of regulatory approval, oncology drug registration failure rates lead all therapeutic areas. Further complicating the drug development process, preclinical oncology models poorly reflect tumor tissue biology and produce a high level of false positive data. Yet, monocellular two-dimensional (2D) tissue culture remains the preferred platform for most laboratory preclinical studies. The popularity of 2D tissue culture was driven predominantly by fast and dependable proliferation of human tumor cells rather than alignment to the pathophysiology of human cancer. As a consequence of this artificial selection bias, many registered oncology drugs today are highly toxic with a propensity to attack any dividing cell (i.e., non-targeted). Fortunately, recent advances in genomics, metabolomics and immunology have aided in development of new targeted agents, many of which have achieved regulatory approval. Nevertheless, rational drug combinations and identification of clinically meaningful drug targets persist as major challenges in oncology, and each can be meaningfully addressed using more diverse and biologically relevant preclinical models. Ex vivo tumor tissue transplant models, such as patient-derived xenografts (PDX) offer greater model diversity and more faithfully reflect patient tumor genetics. However, cost and scalability barriers tend to limit widespread and practical model utility. In addition, there remains a strong selection bias for autocrine human tumors that can quickly adapt to a cross-species mouse host. As a practical alternative to PDX models, we established, serially propagated and molecularly characterized 300 ex vivo 3D (3DX) models spanning 15 tumor indications. Given patient tumor seeding success rates of over 95%, the 3DX-TGA model enabled diverse pharmacologic evaluation for the vast majority of cancer patient models attempted. After achieving sufficient tumor biomass, typically within 7 to 8 weeks, thirty-one drugs were screened for proliferation and viability endpoints over a three-log dose range. Resistance and sensitivity profiles mirrored population-based response rates for indication-aligned FDA-registered drugs. Taken together, the 3DX-TGA model represents a powerful preclinical ex vivo model that: (1.) more faithfully recapitulates human tumor biology, (2.) can be scaled at a fraction of time and cost compared to PDX models, and (3.) provide a superior screening platform for novel drugs and drug-drug combinations. Citation Format: Praveen Nair, Dileep Nair, Kaede Hinata, Cyrus Mirsaidi, Junjie Wu, Yong Hu, Brett M. Hall. Ex vivo three-dimensional tumor growth assay: 3DX-TGA [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5767. doi:10.1158/1538-7445.AM2017-5767

Traditional segment-based model-based OPC methods have been the mainstream mask layout optimization techniques in volume production for memory and embedded memory devices for many device generations. These techniques have been continually optimized over time to meet the ever increasing difficulties of memory and memory periphery patterning. There are a range of difficult issues for patterning embedded memories successfully. These difficulties include the need for a very high level of symmetry and consistency (both within memory cells themselves and between cells) due to circuit effects such as noise margin requirements in SRAMs. Memory cells and access structures consume a large percentage of area in embedded devices so there is a very high return from shrinking the cell area as much as possible. This aggressive scaling leads to very difficult resolution, 2D CD control and process window requirements. Additionally, the range of interactions between mask synthesis corrections of neighboring areas can extend well beyond the size of the memory cell, making it difficult to fully take advantage of the inherent designed cell hierarchy in mask pattern optimization. This is especially true for non-traditional (i.e., less dependent on geometric rule) OPC/RET methods such as inverse lithography techniques (ILT) which inherently have more model-based decisions in their optimizations. New inverse methods such as model-based SRAF placement and ILT are, however, well known to have considerable benefits in finding flexible mask pattern solutions to improve process window, improve 2D CD control, and improve resolution in ultra-dense memory patterns. They also are known to reduce recipe complexity and provide native MRC compliant mask pattern solutions. Unfortunately, ILT is also known to be several times slower than traditional OPC methods due to the increased computational lithographic optimizations it performs. In this paper, we describe and present results for a methodology to greatly improve the ability of ILT to optimize advanced embedded memory designs while retaining significant hierarchy and cell design symmetry, therefore, have good turnaround time and CD uniformity. This paper will explain the enhancements which have been developed in order to overcome the traditional difficulties listed above. These enhancements are in the categories of local CD control, global chip processing options, process window benefit, turn-around time and hierarchy retention.

Oxygen toxicity seizures are a rare but recognized complication of hyperbaric oxygen (HBO2) therapy. Many patients undergoing HBO2 therapy have medical conditions or are taking medications that could contribute to seizures. Previous literature has not extensively reported on these factors in patients experiencing oxygen toxicity seizures. We conducted a chart review at several hyperbaric oxygen centers in the Milwaukee, Wisc., area to explore whether the patients who experienced seizures in the hyperbaric chamber had other medical comorbidities or were on medications which lowered their seizure threshold, thereby contributing to oxygen toxicity seizures. There were a total of seven cases of seizures in five patients. Each patient had risk factors for seizures, including hypercapnia secondary to chronic obstructive pulmonary disease, narcotic withdrawal, alcohol dependence, and antidepressant, tramadol or cephalosporin/ceftriaxone use. We hypothesize that patients who experience oxygen toxicity seizures may have other factors which contribute to the development of these seizures.

Bone marrow stromal cells are an essential regulatory component in the hematopoietic microenvironment. Regulation of hematopoietic cell development is mediated, in part, through interaction of progenitor cells with stromal cell vascular cell adhesion molecule-1 (VCAM-1). VCAM-1 expression has been shown to be driven primarily by binding of nuclear factor-κB (NF-κB) to two consensus binding sites in the promoter region. In this study, we show that down-regulation of VCAM-1 by the chemotherapeutic agent etoposide (VP-16) is associated with altered cellular localization of NF-κB. We demonstrated that VCAM-1 was diminished at the transcriptional level following treatment of stromal cells with VP-16, without alteration of VCAM-1 stability. Culture of bone marrow stromal cells in VP-16 resulted in reduced nuclear RelA (p65), a modest increase in nuclear NF-κB1 (p50), and reduced NF-κB binding to its DNA consensus sequence. Total levels of the NF-κB inhibitor Iκ-Bα were reduced during exposure to VP-16. Following removal of VP-16 from the culture, p65 and p50 nuclear profiles approximated those of untreated stromal cells, and VCAM-1 protein expression was restored. The current study indicates that NF-κB is a target molecule that is responsive to VP-16-induced damage in bone marrow stromal cells. As the primary transcription factor that promotes VCAM-1 expression, the observed changes in p65 and p50 cellular localization during treatment have a direct consequence for stromal cell function. The myriad of genes regulated by NF-κB, including both adhesion molecules and cytokines that contribute to stromal cell function, make chemotherapy-induced disruption of NF-κB biologically significant. Alterations in NF-κB activity may provide one measure by which the effects of aggressive treatment strategies on the bone marrow microenvironment can be evaluated.

We would like to thank Dr Sehgal for his dissenting opinion on the novelty of our recent publication in the 2009 Oncogene issue (Sullivan et al., 2009), and we recognize the importance of the pioneering work by Tamm, Sehgal, and colleagues (Tamm et al., 1989, 1991a, 1991b, 1994a, 1994b, 1998; Krueger et al., 1991; Sehgal and Tamm, 1991) for many aspects of interleukin-6 (IL-6) biology. However, we disagree with the assertions made by Dr Sehgal that a previous body of work has established a phenotypic or a biological signature of epithelial–mesenchymal transition (EMT).

Approximately 20% of B-lineage acute lymphoblastic leukemias are not cured by traditional chemotherapy. The possibility was examined that residual leukemic cells that potentially contribute to relapse are harbored in association with fibroblastic stromal cells in the bone marrow. Modulation of cytarabine (Ara-C) and etoposide (VP-16) efficacy by bone marrow stromal cells in vitro was investigated. Stromal cell coculture was shown to sustain the proliferation of B-lineage leukemic cells and to reduce leukemic cell apoptosis when exposed to Ara-C or VP-16. Direct contact with stromal cells was essential for the protection of leukemic cells during chemotherapy, whereas soluble factors had negligible effect. Specifically, signaling mediated through interaction with the stromal cell adhesion molecule VCAM-1 was required to maintain the maximum viability of leukemic cells during Ara-C and VP-16 exposure. In contrast, the interaction of leukemic cells with fibronectin did not confer significant resistance to either chemotherapeutic agent. These observations suggest a role for the bone marrow microenvironment in modulating the response of B-lineage leukemic cells to Ara-C or VP-16, and they indicate specific molecular interactions that may be important in determining the sensitivity of leukemic cells to treatment.

Introduction: The survival of DLBCL patients who receive immunochemotherapy is correlated with the molecular signature of their tumors. The two most common subtypes which are defined by cell of origin (COO) are the germinal center B cell-like (GCB) and activated B cell-like (ABC) subtypes which have 3-year OS rates of 80% and 45%, respectively when treated with R-CHOP. Several methods have been developed to categorize DLBCL into these sub-types as the treatment they receive directly affects their outcome. Microarray GEP was first used to classify DLBCL into ABC or GCB, with a minority unclassified (UNC), however this is difficult to implement widely and has been replaced by more recent technologies. The most commonly used IHC-based Hans method profiles patients into GCB and non-GCB. The primary focus of this study was to evaluate concordance between current GEP and IHC methods to designate DLBCL subtypes. Methods: For this study, the IHC assay used was a standardized IHC assay based on the Hans algorithm and for the GEP-based assay; the NanoString Technologies Lymphoma Subtyping Test (LST) was used. Commercially available DLBCL samples (N = 138) were confirmed for tumor content and sent to a central laboratory for evaluation by the IHC assay. RNA was extracted from each sample and sent to NanoString for GEP evaluations. To compare methods homogeneously, calls for each method were converted to either “GCB” or “non-GCB”. All “ABC” and “UNC” subtype calls from the NanoString platform was converted to “non-GCB” and any “did not pass” (DNP) calls were converted to not available (NA). All NA values were excluded from the tables and concordance calculations. Results: The Positive Percent Agreement [95% CI] in calling non-GCB between IHC and LST was 87% [78% - 96%] (47/54). Overall concordance between IHC and LST was 80% [73% - 87%] (N = 125, 12 LST samples DNP, 1 IHC sample DNP). The Negative Percent Agreement between IHC and LST (i.e., in calling the GCB sub-type) was 75% [65% - 85%] using the LST result as a non-reference standard (53/71). Conclusions: Given that the success of targeted therapy for the treatment of DLBCL is contingent on the correct identification of sub-type of DLBCL, it is important to adopt a method that accurately and consistently identifies the sub-type in the majority of patients. Given the good concordance between the GEP and IHC methods, DLBCL can be stratified into COO sub-types using either platform. The results show that an optimized Hans IHC assay standardized in a central laboratory offers a robust, relatively inexpensive and accessible platform for cell of origin sub-typing in DLBCL and, with clinical validation, may offer an excellent tool for the selection of optimal therapy. Citation Format: Michael Schaffer, Shalini Chaturvedi, Sandy Frans, Regina Aquino, Jaehong Park, Brett Hall, Sriram Balasubramanian. Concordance of immunohistochemistry (IHC) assay results with gene expression profiling (GEP) methods for diffuse large-B-cell lymphoma (DLBCL) subtype identification. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3187.