Survival Of Mantle Cell Lymphoma Patients Research Articles

Impact of rituximab maintenance on survival of patients with mantle cell lymphoma: A north Indian tertiary care center experience.

e19047 Background: Mantle cell lymphoma (MCL) is an aggressive variant of non-Hodgkin lymphoma. Indian data is scarce owing to its rarity in south-east Asia. Till now, studies have not shown overall survival benefit with rituximab maintenance (RM). Our study aims to assess if RM improves overall survival of MCL patients. Methods: We retrospectively analysed clinicopathological data of 90 transplant-ineligible MCL patients treated between January’2013-December’2023 at Institute Rotary Cancer Hospital - All India Institute of Medical Sciences, New Delhi, India. Rituximab-based induction chemotherapy was used in all patients as per institutional protocol. RM was used in twenty-eight (31.0%) patients due to financial constraints. Primary outcome was overall survival (OS). Secondary outcomes were event free survival (EFS) and factors affecting OS, EFS. OS was defined as time from treatment initiation to demise from any cause or last follow-up. EFS was defined as time from treatment initiation to disease progression or relapse or demise from any cause. Response was assessed by modified Cheson’s lymphoma response evaluation criteria. STATA 13.0 was used to assess survival by Kaplan-Meier analysis and log rank test. Factors affecting survival were assessed by multivariate analysis (Cox proportional hazards model) and expressed as adjusted hazard ratio (aHR). p value < 0.05 defined statistical significance. Results: Median age was sixty years; male-female ratio 3:1. Thirty-five (39.0%) had one or more co-morbidities, 79(88.0%) generalised lymphadenopathy, 72(80.0%) extra-nodal involvement, 49(54.0%) B symptoms, 84(93.0%) advanced stage (III/IV), 49(54.0%) high risk MCL international prognostic index (MIPI). Clinical and tumor characteristics, response rates after initial induction were similar in both maintenance and non-maintenance groups. Overall, 52(58.0%) patients were alive with median follow-up of 63.0 months (inter-quartile range 37.0-90.0 months). Median OS was 37.5 months in non-maintenance group and did not reach in maintenance group. Estimated 1.0-, 2.0, 3.0-year OS were 100.0%, 91.0%, 81.0% vs 75.0%, 63.0%, 55.0% respectively in maintenance vs non-maintenance group. RM was significantly associated with better OS [aHR (95% confidence interval): 0.31 (0.13-0.75), p=0.01]. Advanced stage, Eastern Co-operative Oncology Group performance status (ECOG PS) ≥2 at presentation were also significant factors for poor OS. Median EFS was significantly lower in non-maintenance group [14.0 vs 42.5 months; aHR (95% confidence interval): 0.34 (0.18-0.64), p=0.001]. Advanced stage, anemia, high risk MIPI at presentation were also significant factors for poor EFS. Conclusions: This was the first study from south-east Asia demonstrating impact of rituximab maintenance in MCL. Rituximab maintenance significantly improved OS and EFS of MCL patients.

TIGIT is the central player in T-cell suppression associated with CAR T-cell relapse in mantle cell lymphoma.

BackgroundChimeric antigen receptor (CAR) T-cell therapy using brexucabtagene autoleucel (BA) induces remission in many patients with mantle cell lymphoma (MCL), and BA is the only CAR T-cell therapy approved by the FDA for MCL. However, development of relapses to BA is recognized with poor patient outcomes. Multiple CAR T-cell therapies have been approved for other lymphomas and the resistance mechanisms have been investigated. However, the mechanisms underlying BA relapse in MCL have not been investigated and whether any previously reported resistance mechanisms apply to BA-relapsed patients with MCL is unknown.MethodsTo interrogate BA resistance mechanisms in MCL, we performed single-cell RNA sequencing on 39 longitudinally collected samples from 15 BA-treated patients, and multiplex cytokine profiling on 80 serial samples from 20 patients.ResultsWe demonstrate that after BA relapse, the proportion of T cells, especially cytotoxic T cells (CTLs), decreased among non-tumor cells, while the proportion of myeloid cells correspondingly increased. TIGIT, LAG3, and CD96 were the predominant checkpoint molecules expressed on exhausted T cells and CTLs; only TIGIT was significantly increased after relapse. CTLs expanded during remission, and then contracted during relapse with upregulated TIGIT expression. Tumor cells also acquired TIGIT expression after relapse, leading to the enhanced interaction of tumor cell TIGIT with monocyte CD155/PVR. In myeloid cells, post-relapse HLA-II expression was reduced relative to pretreatment and during remission. Myeloid-derived suppressor cells (MDSCs) were enriched after relapse with elevated expression of activation markers, including CLU (clusterin) and VCAN (versican). Extracellular chemokines (CCL4, CXCL9, CXCL13), soluble checkpoint inhibitors (sPD-L1, sTIM3, s4-1BB), and soluble receptors (sIL-2R, sTNFRII) were decreased during remission but elevated after relapse.ConclusionsOur data demonstrate that multiple tumor-intrinsic and -extrinsic factors are associated with T-cell suppression and BA relapse. Among these, TIGIT appears to be the central player given its elevated expression after BA relapse in not only CTLs but also MCL cells. The acquisition of TIGIT expression on tumor cells is MCL-specific and has not been reported in other CAR T-treated diseases. Together, our data suggest that co-targeting TIGIT may prevent CAR T relapses and thus promote long-term progression-free survival in MCL patients.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12943-022-01655-0.

Paired-Box 5 Positivity Related to High MIPI Score Predicts Shorter Overall Survival in Mantle Cell Lymphoma Patients

Introduction: Mantle cell lymphoma (MCL) is a sub-type of B-cell non-Hodgkin Lymphomas (NHL) that characterized by a heterogenous clinical course and poor prognosis. The transcription factor paired-box 5 (PAX5) is associated with B cell normal differentiation and development. Herein, we aim to explore both the prognostic factors and the role of PAX5 expression in MCL patients from single-center, which can provide theoretical guidance for clinical practice.Methods: The data of 80 MCL patients admitted to Shandong Provincial Hospital from October 2006 to April 2020 were collected to be analyzed. Kaplan-Meier method and univariate and multivariate cox analysis was used to analyze the correlation between overall survival and prognostic factors. Chi-square test, Pearson and Fisher correlation analysis were performed for statistical analysis of clinical features and experimental indicators. *p value<0.05 indicated that the difference was statistically significant. Immunohistochemistry (IHC) was used to label the protein expression. Gene expression profiles were applied to analyze the discrepancy of PAX5 mRNA expression in some lymphoma types.Results: Clinical characteristics of all MCL patients were analyzed. PAX5 expression was identified by IHC in this study: the positive expression rate of PAX5 in all MCL patients was 60% (Figure 1A). The mRNA expression level of PAX5 was obviously elevated in MCL specimens than in normal group compared with other groups (p= 0.034) (Figure 1B). Besides, CD5, CD19, CD22, CD38, CD79α, CD79β and SOX11 were shown co-expressed with PAX5 by string database analysis (Figure 1C). PAX5-related genes were found mainly enriched in lymphocyte activation, B cell proliferation and NOTCH1 signaling pathway (Figure 1D). As is shown in Figure 1E-I, MIPI score (≥6), median to high risk group, high β2-MG level (≥2.65 mg/L), ECOG score (≥2), and splenomegaly were associated with adverse survival (p= 0.006, 0.030, 0.001, 0.019 and 0.001 respectively). The positive expression of PAX5 indicated a shorter overall survival in MCL patients (p= 0.024, Figure 1G). Positive PAX5 expression was associated with international prognostic index (MIPI) score (p= 0.038), high risk stratification (p= 0.006), WBC count (p= 0.024), and increased β2-microglobulin level (p= 0.008). MCL patients with PAX5-positive expression, high level of β2-MG level (≥2.65 mg/L), splenomegaly correlated with a poorer OS (p=0.002, and 0.004 respectively, Figure 1K, L). In patients with PAX5-negative expression, splenomegaly also indicated poor prognosis (p= 0.030, Figure 1M). Furthermore, among patients with high MIPI scores, PAX5-positive MCL patients had a shorter overall survival than PAX5-negative patients (p= 0.016, Figure N, O). Multivariate analysis showed that positive PAX was an independent prognostic factor for poor survival of MCL (p= 0.035).Conclusions: The positive expression of PAX5 in immunohistochemistry may be a factor contributing to the poor prognosis of MCL patients, which is correlated with clinical characteristics and laboratory indicators to a certain extent. Our results the role of PAX5 positivity in MCL and provide clinical guidance for clinical prognostic risk assessment and treatment strategy selection.Keywords: Mantle cell lymphoma; Paired-box 5; Prognosis; Immunohistochemistry [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Abstract PO-04: Noncoding mutations in mantle cell lymphoma disrupt regulation of HNRNPH1 by alternative splicing

Abstract Non-Hodgkin lymphomas (NHL) are a collection of cancers with each malignancy having distinct clinical management and prognosis. Mantle cell lymphoma (MCL) is particularly genetically heterogeneous and is considered incurable. Through a combination of exome, genome, and targeted sequencing of MCL tumors, we identified recurrent mutations in HNRNPH1 (heterogeneous nuclear ribonucleoprotein H1). These mutations are largely intronic or silent and are associated with a putative cis regulatory region involving a single exon. In RNA-seq data from matched cases, we identified variable representation of two distinct HNRNPH1 isoforms. Based on the reading frame of the affected exons, canonical splicing is predicted to produce a functional protein, while alternative splicing introduces a premature termination codon leading to nonsense-mediated decay. We observed a significantly higher proportion of canonical transcripts in MCL tumors bearing HNRNPH1 mutations, leading us to conclude that mutations in HNRNPH1 significantly alter its splicing. Furthermore, increased canonical splicing results in higher HNRNPH1 protein abundance as determined by immunohistochemical analysis of an MCL tissue microarray. HNRNPH1 mutation status and splicing ratio are associated with shorter survival of MCL patients. We developed an in vitro reporter minigene and introduced three specific mutations corresponding to the patient-identified mutations in HNRNPH1. These mutations lead to an increase in canonical splicing and translation of the HNRNPH1 minigene-derived peptide. Additionally, when HNRNPH1 is overexpressed, we observe a decrease of this peptide, implicating HNRNPH1 in the regulation of its own splicing. This is supported by preliminary data indicating that HNRNPH1 binds its own RNA. Beyond its own splicing, HNRNPH1 is likely also involved in the splicing of additional splicing factors. Overexpression of HNRNPH1 affects the splicing of SRSF3 and HNRNPDL, and many other targets are likely to be identified. This work elucidates a functional role for recurrent noncoding HNRNPH1 mutations and implicates HNRNPH1 expression and splicing of its downstream targets in lymphomagenesis. We continue to explore trans regulatory targets of HNRNPH1 using in vitro and cell-based models. While splicing is a growing field of interest in lymphoma biology, the unique pattern and consequences of these largely silent mutations specifically implicate alternative splicing as an oncogenic mechanism in MCL. Citation Format: Krysta M. Coyle, Quratulain Qureshi, Prasath Pararajalingam, Nicole Thomas, Timothy E. Audas, Ryan D. Morin. Noncoding mutations in mantle cell lymphoma disrupt regulation of HNRNPH1 by alternative splicing [abstract]. In: Proceedings of the AACR Virtual Meeting: Advances in Malignant Lymphoma; 2020 Aug 17-19. Philadelphia (PA): AACR; Blood Cancer Discov 2020;1(3_Suppl):Abstract nr PO-04.

Prognostic impact of interim positron emission tomography in mantle cell lymphoma patients treated with frontline R-CHOP.

SummaryAlthough 18F‐fluorodeoxyglucose positron emission tomography (18F‐FDG PET) is commonly used for initial staging and therapeutic response evaluation in aggressive lymphomas, its prognostic utility for mantle cell lymphoma (MCL) is controversial. Therefore, we retrospectively evaluated the correlations of interim PET (iPET) and end‐of‐treatment PET (ePET) response with survival outcomes in 89 consecutive advanced MCL patients treated with frontline R‐CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone). iPET positivity was strongly associated with inferior five‐year overall survival (OS) [hazard ratio (HR) 7·84, P < 0·0001] and poor five‐year progression‐free survival (PFS) (HR 3·34, P < 0·0001). OS and PFS were more favourable in the order early metabolic responder (iPETneg → ePETneg), delayed responder (iPETpos → ePETneg), loss‐metabolic responder (iPETneg → ePETpos), and never‐metabolic responder (iPETpos → ePETpos). In the autologous haematopoietic stem cell transplantation (auto‐HSCT)‐fit subgroup, OS was more favourable in the order early metabolic responders, delayed metabolic responders, and non‐metabolic responders, with a marginal trend toward statistical significance (HR 3·41, P = 0·051), and PFS was significantly superior in early metabolic responders (HR 4·43, P = 0·002). In a group that was ineligible for auto‐HSCT, OS and PFS were significantly superior in early metabolic responders. Our results suggested that iPET is of prognostic value and an independent predictor of survival in MCL patients receiving frontline R‐CHOP. Therefore, prospective clinical trials of iPET‐guided treatment strategies for these patients are warranted.

Increase in survival for patients with mantle cell lymphoma in the era of novel agents in 1995–2013: Findings from Texas and national SEER areas

BackgroundOver the past 20 years, many novel agents and treatment regimens have been developed to treat mantle cell lymphoma (MCL). This study aimed to determine the impact of these new regimens on the survival of MCL patients from 1995 to 2013. MethodsAll newly diagnosed adult MCL patients in the Surveillance, Epidemiology, and End Results (SEER) and Texas Cancer Registry (TCR) databases were included. Patients were grouped into 4 calendar periods based on the time when new novel agents became available: chemotherapy-only (1995–1998, P1), rituximab + chemotherapy (1999–2004, P2), bortezomib and HyperCVAD (2005–2008, P3), bendamustine and Nordic regimen (2009–2013, P4). Associations between these time periods and survival outcomes were analyzed using the Kaplan-Meier method and Cox proportional hazard regressions. ResultsA total of 7,555 SEER patients and 2,055 TCR patients were identified. All-cause mortality rates decreased significantly from 1995 to 2013 (SEER, P < 0.001; TCR, P = 0.03). Multivariable analysis of SEER data showed that the risk of MCL-specific death decreased significantly over the study period with hazard ratios of 0.82 (P2 vs. P1), 0.66 (P3 vs. P1), and 0.58 (P4 vs. P1) (P < 0.0001). Similar results were observed for TCR data (P < 0.0001). In an analysis stratified by tumor stage, only patients with advanced- stage tumors showed a significantly decreased risk of death in both SEER (P < 0.0001) and TCR (P = 0.002) datasets. ConclusionSurvival outcome for MCL patients improved from 1995 to 2013, especially for patients with advanced-stage tumors, potentially reflecting the impact of the introduction of novel agents and new therapeutic regimens.

Increase in Survival for Patients with Mantle Cell Lymphoma in the Era of Novel Agents in 1995-2013: Findings from Texas and National SEER Areas

Abstract Background Over the past 20 years, many novel agents and treatment regimens have been developed to treat mantle cell lymphoma (MCL). This study aimed to determine the impact of these new regimens on the survival of MCL patients from 1995 to 2013. Methods All newly diagnosed adult MCL patients in the Surveillance, Epidemiology, and End Results (SEER) and Texas Cancer Registry (TCR) databases were included. Patients were grouped into 4 calendar periods based on the time when new novel agents became available: chemotherapy-only (1995–1998, P1), rituximab + chemotherapy (1999–2004, P2), bortezomib and HyperCVAD (2005–2008, P3), bendamustine and Nordic regimen (2009–2013, P4). Associations between these time periods and survival outcomes were analyzed using the Kaplan-Meier method and Cox proportional hazard regressions. Results A total of 7,555 SEER patients and 2,055 TCR patients were identified. All-cause mortality rates decreased significantly from 1995 to 2013 (SEER, P Conclusion Survival outcome for MCL patients improved from 1995 to 2013, especially for patients with advanced-stage tumors, potentially reflecting the impact of the introduction of novel agents and new therapeutic regimens.

The Addition of Rituximab to CHOP Improves Failure-Free and Overall Survival of Mantle-Cell Lymphoma Patients – a Pooled Trials Analysis of the German Low-Grade Lymphoma Study Group (GLSG)

Abstract Introduction: Immunochemotherapy has become the standard of care for patients with mantle-cell lymphoma (MCL) (Dreyling et al., ESMO recommendation for MCL, 2013). Previously, the German Low-Grade Lymphoma Study Group (GLSG) has shown in a randomized trial (GLSG2000) that the addition of rituximab to CHOP improves response rates in untreated advanced stage MCL patients (Lenz et al., JCO 2005). However, the trial was not powered to detect survival differences. Since 1996, patients with MCL have been included in the two consecutive randomized trials GLSG1996 (CHOP vs. MCP, Nickenig et al., Cancer 2006) and GLSG2000. Based on the mature pooled data of these trials we now aimed to compare the long-term clinical outcome of MCL patients treated with CHOP with or without rituximab. Methods: Induction treatment consisted of 4-6 cycles of MCP, CHOP, or R-CHOP. Patients younger than 66 years were subsequently randomized to either myeloablative consolidation and autologous stem cell transplantation, or interferon-alpha maintenance in the first European MCL Trial (Dreyling et al., Blood 2005), whereas older patients were designated to interferon-alpha maintenance. In 1998, randomization between CHOP and MCP (GLSG1996) was stopped due to superior response rates and more effective stem cell mobilization after CHOP, and all subsequently recruited patients were assigned to CHOP. Similarly, in 2002, randomization between CHOP and R-CHOP (GLSG2000) was stopped because of superior response rates after R-CHOP, and all subsequently recruited patients were assigned to R-CHOP. For the current evaluation, we included MCL patients prospectively assigned to either CHOP (GLSG1996 or GLSG2000) or R-CHOP (GLSG2000). We performed an intention-to-treat analysis comparing failure-free (failure: stable disease, progression, or death from any cause) and overall survival (OS) of patients prospectively assigned to R-CHOP versus CHOP, adjusting for potential imbalances in clinical risk profile based on the MIPI score (Hoster et al., JCO 2014). Results: From 1996 to 2004, 386 MCL patients have been prospectively assigned to R-CHOP (185) or CHOP (201). Clinical characteristics were comparable with median age 62 vs. 61 years for R-CHOP vs. CHOP groups, and 40% vs. 42% low risk, 38% vs. 36% intermediate risk, and 22% vs. 21% high risk MIPI. The R-CHOP group showed higher overall response (91% vs. 80%) and complete remission rates (25% vs. 15%). Median failure-free survival was 2.1 compared to 1.4 years (Figure 1, left panel) with adjusted hazard ratio 0.62 (95% CI 0.50-0.78, p&lt;0.0001). After a median follow-up of 9.6 years, median OS was 5.9 vs. 4.8 years with adjusted hazard ratio 0.73 (95% CI 0.57-0.94, p=0.0166) and 5-year OS rates of 57% vs. 48% (Figure 1, right panel), confirming the randomized comparison (5-year OS rates, 59% vs. 47%, adjusted hazard ratio 0.74, 95% CI 0.50-1.09). OS curves of CHOP patients in GLSG1996 or GLSG2000 were overlapping as well as OS curves of patients with randomization or fixed assignment to R-CHOP in GLSG2000. Conclusions: After longer follow-up, pooled data of prospective GLSG trials showed prolonged survival by the addition of rituximab to CHOP induction in previously untreated MCL patients. Our results confirm the recommendation for immunochemotherapy as standard treatment for MCL. Compared to previous observations, clinical outcome for MCL patients has improved; however, further improvement by the introduction of more potent chemotherapy (e.g. high-dose cytarabine) or new targeted approaches is urgently warranted. Figure 1: Failure-free (left) and overall survival (right) of patients prospectively assigned to R-CHOP or CHOP in GLSG1996 or GLSG2000 trials Figure 1:. Failure-free (left) and overall survival (right) of patients prospectively assigned to R-CHOP or CHOP in GLSG1996 or GLSG2000 trials Figure 2 Figure 2. Disclosures Hoster: Roche: Travel Support Other. Off Label Use: Rituximab in mantle-cell lymphoma. Unterhalt:Roche: Travel Support Other. Hallek:Roche: Consultancy, Research Funding. Klapper:Roche: Research Funding. Dreyling:Roche: Honoraria, Research Funding. Hiddemann:Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.

Diagnostic Tumor Mirna Profiling Predicts Molecular Relapse in Mantle Cell Lymphoma Patients Prospectively Followed for Minimal Residual Disease. Results from the Nordic MCL2-3 Trials

Background Mantle cell lymphoma (MCL) is a subtype of non-Hodgkin‘s lymphoma (NHL) with a variable but often aggressive clinical course. The majority of MCL patients ≤65 years will experience clinical relapse during a 10-year period (Geisler et al. Br J Haematol 2012). Risk-stratification is therefore of great importance in order to identify patients who are eligible for novel or alternative treatment regimens. Minimal residual disease (MRD) monitoring can predict clinical progression in MCL and guide pre-emptive treatment with rituximab as single agent. It has thus far not been possible to predict post-treatment molecular relapse (MRD-positivity). Although some recent studies have shown that aberrant miRNA expression delineate pathogenic molecular pathways and predict survival in MCL patients, miRNA profiling has not been performed in the context of MRD and molecular relapse.Aims We assessed MCL miRNA expression, in a large, prospective, uniformly treated patient cohort followed with molecular markers for MRD to determine if miRNAs could predict molecular relapse.Methods Diagnostic MCL tumor samples from 114 patients in the Nordic MCL2 and MCL3 clinical trials were retrieved. All patients had confirmed CyclinD1 overexpression and 96 patients had Ki-67 expression measurement for use in the MIPI-B predictive score. All patients received almost identical induction treatment with six alternating cycles of maxi-CHOP and high-dose Ara-C in combination with rituximab. Patients in remission were consolidated with high dose chemotherapy followed by autologous stem cell transplantation. All patients had a molecular marker (PCR detectable t(11;14) or clonal IgH rearrangement) for MRD. The median follow-up was 6.4 years for the MCL2 cohort and 3.7 years for the MCL3 cohort. 19 miRNAs, previously found to have prognostic significance in MCL (Husby et al EHA 2014), were measured by qRT-PCR and analyzed in concordance with MRD-data. The main endpoint was first event of molecular relapse (MRD-positive sample).Results Of the 114 patients in the study, 71 (62%) patients became MRD-positive in the follow-up period. Of the 19 examined miRNAs, 10 miRNAs showed unique qPCR melting curves and were analyzed with respect to MRD. Four miRNAs (miR-92a, miR-3687, miR-486-5p and miR-185-5p) were significantly up-regulated in patients who had molecular relapse (t-test; respectively p = 0.010, p = 0.019, p = 0.048, p = 0.043). However miR-18b, previously identified as prognostic marker regarding survival, was not significantly overexpressed. We hereafter investigated if a newly derived prognostic score, the MIPI-B-miR, which incorporates miR-18b with the MIPI-B, could predict molecular relapse. The MIPI-B-miR high-risk patients had significantly shorter time to first molecular relapse than MIPI-B high-risk patients (Figure 1). Functional studies of these aberrantly expressed miRs are ongoing.Conclusion Patients with molecular relapse had significantly increased levels of miR-92a, miR-3687, miR-486-5p and miR-185-5p, and MIPI-B-miR improved MRD prediction compared to MIPI-B. Aberrant miRNA profiles may be able to predict molecular relapse, and may already at diagnosis identify patients eligible to anti-CD20 antibody maintenance or alternative regimens. However validation in other cohorts is needed. [Display omitted] DisclosuresKolstad:Nordic Nanovector: Membership on an entity’s Board of Directors or advisory committees, Research Funding. Räty:GlaxoSmithKline Ltd: Honoraria; Roche Ltd: Membership on an entity’s Board of Directors or advisory committees; Mundipharma: Honoraria.

Bendamustine in mantle cell lymphoma

SUMMARY Mantle cell lymphoma (MCL) is generally considered incurable and has the worst overall survival among B-cell lymphoma subtypes. The disease usually responds well to initial therapy but most patients relapse and then respond only briefly to salvage therapy. Nevertheless, the median overall survival of MCL patients has dramatically improved from 2 to 3 years of the 90’s to more than 5 years at present. This improvement was due either to the introduction of dose-intensive strategies and/or high-dose therapy upfront in younger patients, and to the availability of novel agents in older patients or in the relapsed/refractory setting. Bendamustine, mostly in combination with rituximab, has been recently introduced in the armamentarium for treating patients with MCL with surprising results. Its efficacy and tolerability compare favorably with any other cytotoxic drug or drug combinations for treating patients with MCL, as summarized in this review. Due to its favorable toxicity profile, bendamustine is now increasingly combined with other active compounds. Cytosine arabinoside, which is well known for its striking activity in younger patients with MCL, has been combined with bendamustine in the rituximab, bendamustine and cytarabine (R-BAC) regimen with promising results. Other novel agents, that are approved in Europe or in the United States for the treatment of MCL, like bortezomib, lenalidomide, temsirolimus, and drugs targeting the B-cell receptor pathway (idelalisib, ibrutinib), are under investigation in combination with bendamustine. These molecules provide an opportunity to build up on the regimens used in MCL either in combination with bendamustine upfront, or as maintenance, and will open new frontiers in the treatment of patients with MCL.

Using primary site as a predictor of survival in mantle cell lymphoma

Mantle cell lymphoma (MCL) is a rare B cell lymphoma that varies in clinical behavior with some patients experiencing aggressive disease with short survival, whereas others have indolent behavior. We examined the association between primary disease site and survival in MCL patients to identify subgroups with distinct characteristics. We analyzed the United States Surveillance, Epidemiology and End Results Program database for MCL cases reported from 2000 through 2009. Kaplan-Meier curves and Cox proportional hazard models were used to estimate the effect of primary site on survival. Among 4477 cases included in our study, 19.6% of patients presented with an extranodal primary site. The most common extranodal primary sites were of the gastrointestinal (GI) tract (7.8%), the head and neck (6.2%), and the hematologic/reticuloendothelial systems (3.6%). Asians/Pacific Islanders were more likely than whites or blacks to have GI tract or head and neck disease (P < .0001 and P = .002, respectively). Advanced disease and B symptoms were less common in those with primary disease of the GI tract or head and neck than in those with primary disease of the lymph nodes (both P < .0001). In a multivariate Cox regression model, patients with primary disease of the GI tract and head and neck had superior survival compared to those with primary disease of the lymph nodes; hazard ratios 0.75 (95% CI = 0.62-0.90) and 0.68 (95% CI = 0.55-0.85), respectively. Primary site of disease may be an important prognostic factor for patients with MCL. Further studies elucidating a biological basis for these differences are needed.

SOX11 Directly Represses Wnt/β-Catenin Signaling and Identifies a Subgroup of Mantle Cell Lymphoma Patients with Improved Survival with Intensive Treatment

AbstractAbstract 895The SOX11 (Sex determining region Y)-box 11 transcription factor is aberrantly expressed in the majority (78-93%) of Mantle Cell Lymphoma (MCL) patients. Functionally, SOX11 represses MCL cell proliferation in vitro. We identify SOX11 mediated repression of Wnt signaling as contributory to the proliferation block in vitro and determine the clinical consequences of SOX11 overexpression in a meta-analysis of 3 large international patient cohorts.We have previously identified SOX11 direct binding target genes using chromatin immunoprecipitation coupled with high resolution, next generation sequencing (ChIP-Seq). Members of the Wnt signaling pathway, which is known to promote proliferation in MCL, were significantly enriched in our ChIP analysis in MCL patients and cell lines. Using a luciferase reporter assay for nuclear beta-catenin activity, we find that overexpression of SOX11 represses Wnt signaling (p<0.005) in vitro in Z138 and JEKO-1 cells. Conversely, depletion of SOX11 using siRNA increased Wnt signaling (p<0.05) in the same cell lines. The overexpression phenotype is characterized by G2/M arrest and proliferation block in five MCL cell lines studied, irrespective of p53 status or endogenous SOX11 levels.The relationship between SOX11 and proliferation was validated in primary patient samples. Interrogation of an eighty-two patient gene-expression dataset demonstrates that SOX11 mRNA expression is significantly (p<0.05) and inversely proportional to Ki-67, a marker of cell proliferation. Similarly, expression of SOX11 is inversely proportional to beta-catenin (p<0.05) supporting our in vitro data showing crosstalk between SOX11 and Wnt pathways in SOX11 mediated repression of cell proliferation in MCL.Prior studies examining the impact of SOX11 expression on patient outcomes using immunohistochemistry have been hampered by small numbers and heterogeneity in treatment. To overcome patient selection and treatment biases, we analyzed SOX11 expression in a total of 386 patients from three independent well-annotated tissue microarrays from University of Wisconsin, Karolinska Institute and British Columbia Cancer Agency. Higher SOX11 expression was associated with improved overall survival (p<0.03) in patients treated with intensive regimens such as R-Hyper-CVAD or VCR-CVAD, independent of IPI/MIPI or p53 overexpression in these patients and similar to reports in epithelial malignancies. Conversely, there was no significant impact of SOX11 expression on survival in R-CHOP treated patients.In conclusion, building from our previous ChIP-seq data, we further validated the inverse association between SOX11 and proliferation in primary patient samples. Our functional data showing direct repression of Wnt signaling represents one pathway through which SOX11 can exert its anti-proliferative effect. Our meta-analysis indicates that higher SOX11 expression is associated with improved survival in MCL patients treated with intensive chemotherapy. This supports prospective validation of SOX11 as a bioassay to select patients more likely to benefit from intensive therapy in MCL. Transcriptional regulation of Wnt and other biological pathways affected by SOX11 target genes help explain the impact of SOX11 expression on patient outcomes. Disclosures:Goy:Milennium: Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau; Celgene: Membership on an entity’s Board of Directors or advisory committees; Seattle Genetics: Membership on an entity’s Board of Directors or advisory committees; Pharmacyclics: Membership on an entity’s Board of Directors or advisory committees; J & J: Membership on an entity’s Board of Directors or advisory committees; Pfizer: Membership on an entity’s Board of Directors or advisory committees.

Novel therapy for therapy-resistant mantle cell lymphoma: Multipronged approach with targeting of hedgehog signaling

Mantle cell lymphoma (MCL) is one of the most aggressive B-cell lymphomas with a median patient survival of only 5-7 years. The failure of existing therapies is mainly due to disease relapse when therapy-resistant tumor cells remain after chemotherapy. Therefore, development and testing of novel therapeutic strategies to target these therapy-resistant MCL are needed. Here, we developed an in vivo model of therapy-resistant MCL by transplanting a patient-derived MCL cell line (Granta 519) into NOD/SCID mice followed by treatment with combination chemotherapy. Cytomorphologic, immunophenotypic, in vitro and in vivo growth analyses of these therapy-resistant MCL cells confirm their MCL origin and resistance to chemotherapy. Moreover, quantitative real-time PCR revealed the upregulation of GLI transcription factors, which are mediators of the hedgehog signaling pathway, in these therapy-resistant MCL cells. Therefore, we developed an effective therapeutic strategy for resistant MCL by treating the NOD/SCID mice bearing Granta 519 MCL with CHOP chemotherapy to reduce tumor burden combined with GLI-antisense oligonucleotides or bortezomib, a proteosome inhibitor, to target therapy-resistant MCL cells that remained after chemotherapy. This regimen was followed by treatment with MCL-specific cytotoxic T lymphocytes to eliminate all detectable leftover minimal residual disease. Mice treated with this strategy showed a significantly increased survival and decreased tumor burden compared to the mice in all other groups. Such therapeutic strategies that combine chemotherapy with targeted therapy followed by tumor-specific immunotherapy are effective and have excellent potential for clinical application to provide long-term, disease-free survival in MCL patients.

Prognostic Impact of Clinical and Tumor Associated Variables in a Population-Based Cohort of Mantle Cell Lymphomas in the Stockholm Region Between 1998–2010

Abstract 1592 Introduction:Mantle cell lymphoma (MCL) constitutes 3–10% of non-Hodgkin lymphomas and affects predominantly middle-aged to elderly men. The median survival is 3–5 years and seems to improve with new therapeutic regimens. The MCL International Prognostic Index (MIPI) has been proven useful for predicting survival in MCL patients included in clinical trials, but its value in unselected population based MCL cohorts is less well known. Biological markers are increasingly used for prognostication of MCL patients, especially for defining indolent cases. Material and Methods:All 186 patients diagnosed with MCL, confirmed by IHC for cyclinD1 and/or by FISH for t(11;14), between January 1998 and June 2010 in the Stockholm region, were included in a retrospective analysis. Clinical data from patient files, diagnostic biopsies and flow cytometry data were reviewed. Last follow-up was in May 2011.The prognostic value of the following variables, evaluated at the time of diagnosis, were analyzed: age, sex, Ann Arbor stage, ECOG, B-symptoms, Hb, LDH, albumin, lymphocytosis, leukocytosis, splenomegaly, nodal, extranodal and bone marrow involvement, blastoid morphology, expression of CD23, light chain, Ki 67, p53 and nuclear SOX11. Results:The median age at diagnosis was 68.8 years (range 36.2 – 89.9); 67.4 in males and 72.1 in females, respectively. The male: female ratio was 2. Thirty patients had a known malignancy of other type before the MCL diagnosis and 12 acquired a cancer later. In 13 patients the other malignancy was the cause of death. Median overall survival (OS) time was 43 months in the whole cohort and 38 months, when excluding 39 patients receiving ASCT as part of first-line therapy. No statistically significant difference in OS was seen with respect to whether the lymphoma was diagnosed before or after 2005.In the non-transplanted patients (n=149), univariate analysis showed the following clinical variables to be negatively correlated to overall survival: age >65 years, B-symptoms, splenomegaly, ECOG >2, low albumin, and high LDH. The median survival was not reached in the low risk MIPI group, and was 79 and 34 months, in the middle and high risk MIPI group, respectively. Blastoid morphology and p53 positivity (>20%), were negatively correlated to overall survival (both with p<0.0001), as was increasing tumor cell proliferation (measured as a continous variable or using the cut-offs >50%, both with with p<0.0001), but not with cut-off >30% (p=0.061), while SOX11 positivity was related to a prolonged survival (p=0.015). Multivariate analyses showed that age >65 (HR 6.1, p<0,002), ECOG >2 (HR 63, p<0.001), high LD (HR 3.7, p< 0.001), and p53 positivity (HR 5.6, p< 0.0001) remained significant.Clinically indolent MCL, defined as in retrospect not requiring treatment within two years from diagnosis, was seen in 17 patients. In two of these patients the proliferation was >30%, in one >50%, two had a p53 expression >20% and two were SOX11 negative. Therapy was never required in 9 of these initially indolent patients and only one had an autologous transplantion later in the disease course. The median OS was 72 months for the 17 indolent MCL compared with 34 months in patients requiring treatment earlier in their disease (p=0.003). The follow-up time did not differ significantly between the two groups. Conclusions:Compared to data from published clinical trials of advanced MCL, our population-based cohort of 186 cyclin D1 positive MCL patients were diagnosed at an older age, which may contribute to a shorter overall survival. Certain well-established prognostic variables seem to loose significance outside study populations.In the group of 147 non-transplanted patients multivariate analysis showed that only age, ECOG, LDH and p53 positivity were independently associated with overall survival. Leukocytosis as a variable of MIPI had no impact. Neither SOX11, CD23 or other biological markers applied at the time of diagnosis could predict for clinically indolent disease. Disclosures:No relevant conflicts of interest to declare.

The Mir-17~92 Cluster Enhances Cell Growth and Resistance to Chemotherapy in Mantle Cell Lymphoma by Down-Regulating PTEN, PHLPP2 and BIM

Mantle cell lymphoma (MCL) is an aggressive B-cell malignancy and is characterized by the chromosome translocation t(11;14)(q13;q32), which results in aberrant expression of cyclin D1. The t(11;14)(q13;q32) alone is not sufficient to result in lymphoma, and additional genetic alterations are necessary. Secondary genomic alterations are frequently detected in MCL, of which chromosome 13q31–q32 gain/amplification is one of the most frequent. Amplification at chromosome 13q31–q32 targets a microRNA cluster, miR-17~92, which resides within intron 3 of c13orf25, a non-protein-coding gene at 13q31.3. The miR-17~92 cluster consists of seven miRNAs, and overexpression of the cluster accelerates the development of MYC-induced lymphoma in mice and contributes to carcinogenesis in the lung. Nevertheless, the functional role of miR-17~92 in MCL has not been investigated. Based on gene expression profiling study of 82 primary MCL biopsy specimens using whole genome Affymetrix U133 2.0 plus arrays, we found that overexpression of miR-17~92 was associated with worse overall survival in patients with MCL (p=0.021). We further demonstrated that enforced expression of miR-17~92 reduced chemotherapy-induced apoptosis in retrovirally transduced MCL cell lines. Immunoblot analysis showed that PTEN was down-modulated in MCL cells with overexpression of miR-17~92, and the level of PTEN was restored with reduction of miR-20a levels using an antisense oligonucleotide or a “sponge” plasmid with multiple tandem miR-20a binding sites. The finding was further confirmed by luciferase assays using a reporter plasmid containing the PTEN 3′UTR, and the effect was abrogated by mutating the miR-20 binding site in reporter plasmid, indicating that PTEN was downregulated through the binding of miRNA to the 3′UTR of the transcript. Furthermore, we demonstrated that overexpression of miR-17~92 in MCL cells increased the phosphorylation of AKT and its downstream targets. Interestingly, we found that the protein phosphatase PHLPP2, a negative regulator of the PI3K/Akt pathway, was also a direct target of the miR-17~92 cluster. Moreover, we found that BIM, a BH3-only proapoptotic protein, was a direct target of the miR-17~92 and down-modulation of BIM negatively impacted the intrinsic pathway of apoptosis. In summary, we demonstrated that overexpression of miR-17~92 in MCL cells downmodulates multiple proteins involved in PI3K/Akt signaling and apoptosis, and that downregulation of these targets collaboratively enhances cell growth and chemoresistance in tumor cells. As a consequence, overexpression of miR-17~92 may be associated with poorer survival in MCL patients. Our findings disclose a novel oncogenic pathway in MCL and suggest that targeting the miR-17~92 cluster may provide a novel therapeutic approach for this disease, which is incurable with current chemotherapeutic regimens.

Correlation of Quantitative Gene Expression by RQ-PCR with Clinical and Biologic Factors in Mantle Cell Lymphoma.

Mantle cell lymphoma (MCL) is characterized by an aggressive clinical course and the t(11;14) translocation leading to overexpression of cyclin D1 (CCND1). Recently, a relation between the quantitative expression of proliferation associated genes including CCND1 and the survival of MCL patients has been demonstrated using microarray gene expression profiling. In the current study a set of genes (CCND1, CCND3, CDK2, CDK4, p16, p27, Rb, E2F1, MYC, Ki-67, BMI, MCL-1, MDM2, ATM, TP53) involved in cell cycle regulation, related to MCL pathogenesis, or located in critical genomic regions was analyzed by real-time RT-PCR (RQ-PCR) in 74 MCL cases and correlated with clinical and biologic factors. Diagnoses were based on morphology and the detection of the t(11;14) and/or CCND1 overexpression on protein or mRNA level. 62 cases were classical MCL, 12 blastoid variants. To obtain a quantitative estimate of the relation between the expression the CCND1 1.7 kb (short; missing 3′ UTR) and 4.5 kb (long; containing 3′ UTR) mRNA isoform a first amplicon was localized in the CCND1 coding region and a second one in the CCND1 3′ UTR. FISH analysis was performed in a subset of 40 cases for 3q26, 6q27, 9p21, 11q22–q23, 12q13, 13q14, and 17p13. As a marker for proliferation activity the mitotic index (MI) was determined in 51 cases (mitoses/10 high power fields). Survival information was available for all cases, additional clinical information (IPI, B-symptoms, tumor bulk) for 60 cases. In univariable analysis a statistically significant association between gene expression levels and overall survival was identified for MYC (p=0.003), BMI (p=0.027), and CCND1 (coding region; p=0.028). A multivariable analysis including clinical factors of known prognostic impact (IPI score, B-Symptoms, Bulk, blastoid morphology) was carried out for each of the candidate genes individually. In this analysis a significant impact on survival was observed for MYC (p=0.008), BMI (p=0.021), and E2F1 (p=0.042), and a trend for Ki-67 (p=0.054), the ratio CCND1 coding region/CCND1 3′ UTR (p=0.062), and CCND1 coding region (p=0.082). Notably, and in contrast to the other genes of prognostic significance, BMI overexpression was positively correlated with overall survival times. In line with this, there was a negative correlation of BMI levels with proliferation activity as measured by the MI (p<0.001; r=−0.515). Other genes with a negative MI correlation were MCL-1 (p<0.001; r=−0.532) and p27 (p<0.001; r=−0.589), whereas the ratio CCND1 coding region/CCND1 3′ UTR showed a positive correlation (p<0.001; r=0.523). Genomic losses at 9p21 and 17p13 were associated with reduced levels of p16 (p=0.002) and TP53 (p=0.011), respectively, arguing for a pathogenic relevance of these candidate genes in MCL. However, neither p16 nor TP53 expression levels obtained prognostic significance in our MCL series. In conclusion, focused RQ-PCR analysis of individual candidate genes showed a correlation between quantitative gene expression and survival times in MCL. In addition to CCND1 expression levels of MYC, BMI, and E2F1 provided prognostic information also in the context of clinical factors suggesting those factors being valuable survival predictors and important components of MCL pathogenesis.

Rituximab/Chemotherapy Induction Treatment Followed by High-Dose Therapy and Autologous Transplantation in Patients with Mantle Cell Lymphoma.

Between September 1998 and September 2003, 25 patients with Mantle Cell Lymphoma (MCL) were treated in our centres with a treatment combining rituximab + chemotherapy at induction with subsequent consolidation high-dose chemo/radiotherapy (HDT) and autologous PBSC-transplantation. Twenty-two (80%) patients received this treatment in first line therapy. Median age of patients was 53 (range: 41–65). All patients had a disseminated disease with a bone marrow (BM) involvement in 23 (92%) patients. Elevated LDH was present in 11 patients. All patients except one had a good performance status. IPI score was low in 5 patients, low-intermediate in 10 patients, high-intermediate in 7 patients and high in 3 patients. Chemotherapy induction regimens were: R-CHOP (n=7 pts), R-ACVB (n=4 pts), R-ESHAP (n=1 pts), R-DHAP (n=1pts), or sequential CHOP+DHAP/ESHAP+Rituximab (n=12pts) regimens. Rituximab was giving simultaneously with the chemotherapy in 13 patients or just before harvest in 12 patients. Number of rituximab injections was four in all patients except one that received 5 injections. PBSC harvest was done after cyclophosphamide or cyclophosphmide + etoposide followed by G-CSF and was successful in all patients with a median number of CD34+ cells at 6.44 106/kg. HDT included TBI in 21 patients.After induction therapy, all patients were in response: 16 (64%) reached a CR and 9 (36%) a PR because of persistence of a weak (<5%) BM involvement. Evaluation three months after transplant showed a CR in 17 (68%) patients and a PR in 7 (24%) patients because of weak BM involvement. At 3 years, 80% (20/25) of the patients are still alive (Figure). With a median follow-up at 4 years, median time to progression was 3.3 years. Four patients died from progressive disease. Transplantation toxicities were similar to those observed with regular induction treatment without rituximab with a median time of achievement of a PN count > 0.5GI/L at 10 days. One patient died before neutrophil recovery because of undocumented pulmonary infection. No patient presented late neutropenia. In conclusion, combined induction chemotherapy with rituximab followed by HDT dramatically improved the overall survival and the progression free survival in MCL patients, without adding hematological toxicities and infectious complications. [Display omitted]