Mantle Cell Lymphoma Patients Research Articles

PRMT5 activates lipid metabolic reprogramming via MYC contributing to the growth and survival of mantle cell lymphoma

Mantle cell lymphoma (MCL) is an incurable and aggressive subtype of non-Hodgkin B-cell lymphoma. Increased lipid uptake, storage, and lipogenesis occur in a variety of cancers and contribute to rapid tumor growth. However, no data has been explored for the roles of lipid metabolism reprogramming in MCL. Here, we identified aberrant lipid metabolism reprogramming and PRMT5 as a key regulator of cholesterol and fatty acid metabolism reprogramming in MCL patients. High PRMT5 expression predicts adverse outcome prognosis in 105 patients with MCL and GEO database (GSE93291). PRMT5 deficiency resulted in proliferation defects and cell death by CRISPR/Cas9 editing. Moreover, PRMT5 inhibitors including SH3765 and EPZ015666 worked through blocking SREBP1/2 and FASN expression in MCL. Furthermore, PRMT5 was significantly associated with MYC expression in 105 MCL samples and the GEO database (GSE93291). CRISPR MYC knockout indicated PRMT5 can promote MCL outgrowth by inducing SREBP1/2 and FASN expression through the MYC pathway.

Abstract 2997: Identification of novel long non-coding RNAs in mantle cell lymphoma patients

Abstract Mantle Cell Lymphoma (MCL) is a rare and incurable type of B-cell non-Hodgkin lymphoma that affects about 4,000 people per year in the United States. Despite intense research to identify novel therapeutic approaches, the median progression-free survival after first-line treatment is four years. For this reason, the discovery of novel therapeutic targets remains crucial. Over half of the human genome is actively transcribed as non-coding RNAs. Among them, the non-coding RNAs that are longer than 200 nucleotides are named long non-coding RNAs (lncRNAs). lncRNAs have been shown to play essential roles in several human diseases, including cancer, by modulating cell cycle, immune response, or stemness through their interactions with DNA, protein, and RNA. For this reason, we decided to perform an RNA sequencing (RNA-Seq) profiling to identify the dysregulated lncRNAs in MCL. In more detail, we performed RNA-Seq in a cohort of 18 MCL patients compared to normal B-cells from the peripheral blood of healthy donors (HD). Reads were first trimmed for quality filtering, and adapters were removed using Trim Galore. Trimmed reads were mapped to the human genome (HG38 assembly) using HISAT 2. All the reads mapped inside the genomic coordinates of lncRNAs, reported in the GTF annotation file of GENCODE v43, were counted by featureCounts. Differential expression analysis between MCL samples vs HD was performed by LIMMA. To validate the results obtained from our internal MCL cohort, we also downloaded publicly available RNA-Seq data of 16 MCL patients and analyzed them using the previously described pipeline. Our analyses revealed several dysregulations in lncRNA expression occurring in MCL. Precisely, we identified 385 upregulated and 387 downregulated lncRNAs (|log2FC| > 0.58 and adjusted p-value < 0.05) in our internal MCL cohort, and 63% of them were also confirmed in the external cohort. Notably, the lncRNA called MALAT1 showed the highest significant upregulation in both cohorts, reinforcing this lncRNA's pivotal role in cancer development. To study the potential involvement of MALAT1 in MCL, we compared the MCL samples with higher MALAT1 expression (upper quartile) against those with lower expression (lower quartile) in both cohorts. The identified differentially expressed genes were used as input for a mechanistic network-based topological pathway analysis using MITHrIL. The analysis revealed that the KEGG pathway "Cell Cycle" was among the top upregulated pathways in MCL samples with high MALAT1 expression, suggesting the relevance of this lncRNA in promoting cellular proliferation, as also reported in the literature for other tumor types. In conclusion, our is the first study to describe the novel dysregulation signature of lncRNAs in MCL in two independent cohorts. Citation Format: Alessandro LaFerlita, Satishkumar Singh, Anuvrat Sircar, Robert Baiocchi, Natarajan Muthusamy, Lapo Alinari, Narendranath Epperla, Lalit Sehgal. Identification of novel long non-coding RNAs in mantle cell lymphoma patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2997.

Abstract 649: SOX11 regulates BCR signaling via the PAX5/CD19 axis in MCL

Abstract Background: Mantle cell lymphoma (MCL) is an incurable lymphoid neoplasm, comprising about 6% of all non-Hodgkin lymphoma (NHL). The transcription factor SOX11 is overexpressed in the majority of MCL patients and linked to a more aggressive disease course and poorer clinical outcomes. In MCL, naïve B cells experience continuous proliferation because of the dysregulation of the B-cell receptor (BCR) pathway. Our previously published data (Kuo et. al., Blood 2018) identified that SOX11 aberrantly upregulated BCR signaling in transgenic mouse models. The current study describes the exact mechanism by which SOX11 regulates the BCR pathway using a combination of functional and pharmacological approaches. Methods: To investigate the alterations in signaling pathways regulated by SOX11, we utilized a small molecule SOX11 inhibitor (Jatiani et. al., CCR 2021), performed CRISPR/CAS9 knockout of SOX11, 3X FLAG TAG overexpression, as well as conducted western blot and flow-cytometry experiments. Results: Our prior published results (Kuo et. al., Oncogene 2015), as well as others (Vegliante et. al., Blood 2013), have shown that PAX5 is a direct target of SOX11. We confirmed PAX5 downregulation after SOX11 depletion in three human MCL cell lines (JEKO, MINO, Z138) using CRISPR-CAS9. Decrease of PAX5 expression was associated with reduction in CD19 expression and a concurrent reduction in phospho-BTK (Bruton tyrosine kinase). Conversely, overexpression of SOX11 could rescue PAX5/CD19 expression and restore p-BTK levels. Furthermore, the treatment of SOX11 expressing cells with small molecule SOX11-specific inhibitors resulted in a reduction in PAX5, CD19 and BCR activation (p-BTK). Conclusion: Taken together, these findings delineate PAX5 as the direct target and PAX5/CD19 axis as the downstream pathway by which SOX11 regulates B-cell receptor (BCR) signaling in MCL. Notably, our treatment using a SOX11 inhibitor successfully replicated the effects observed with genetic knockdown. In conclusion, our findings provide valuable insights into the molecular mechanisms by which SOX11 contributes to MCL pathogenesis. The further development of pharmacological inhibitors targeting SOX11 holds promise as a beneficial therapeutic strategy for MCL patients, as these will block signaling upstream of current resistance mechanisms. Citation Format: Rudra Prasad Dutta, Heng-Huan Lee, Violetta V Leshchenko, Ravi Prakash Shukla, Yang Liu, Jian Jin, Michael Wang, Samir Parekh. SOX11 regulates BCR signaling via the PAX5/CD19 axis in MCL [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 649.

Abstract 602: Targeting CDK9 with a novel potent and selective inhibitor, YX0798, in CAR-T-relapsed mantle cell lymphoma models

Abstract Introduction: Cyclin-dependent kinase (CDK) family members play critical roles in multiple cellular processes. CDK9 is a central regulator at several stages of PolII transcription, including initiation, elongation, and termination. CDK9 dysfunction resulted in transcriptomic reprogramming and promotion of the development of cancers, including lymphoma and leukemia. We and others reported that transcriptomic reprogramming is associated with disease progression and therapeutic resistance in mantle cell lymphoma (MCL). Targeting CDK9 with its inhibitors AZD4573 and enitociclib is safe and effective for treatment in preclinical MCL models, and they are currently under clinical investigation to assess their efficacy and safety. The data demonstrated that CDK9 is a promising therapeutic target. In this study, we developed a novel CDK9 inhibitor, YX0798, and assessed its potency and safety in preclinical MCL models. Method: Cell viability assays were conducted in a time- and dose-dependent manner to assess the in vitro efficacy of YX0798 as well as AZD4573. Apoptosis assays and western blots were used to determine the mechanism of action in MCL cells. Patient-derived xenograft models from primary MCL patient samples were established in immunodeficient mice and used to determine the therapeutic potential YX0798. Results: Next generation sequencing showed that CDK9 was upregulated and cancer hallmarks MYC-TARGETS-v1 and -v2 were highly enriched in CAR-T-relapsed MCL patients compared to CAR-T-naïve patients. We hypothesized that CDK9 overexpression and activity may greatly contribute to the enrichment of MYC-TARGETS-v1 and -v2 in patients with CAR-T resistance, so targeting CDK9 may overcome that resistance. YX0798 was developed to be a potent and selective CDK9 inhibitor. It markedly inhibited cell viability and induced robust apoptosis in MCL cell lines. As expected, it inhibited CDK9 kinase activity and suppressed the expression of short-lived proteins like c-MYC and MCL-1 that are critical for MCL cell survival and growth. YX0798 at 2 mg/kg for continuous 7 days via pump or at 5 mg/kg daily by oral administration potently inhibited the tumor growth of xenografts derived from a patient with therapeutic relapse to the CAR-T therapy in vivo (P<0.0001). This treatment efficacy was found to be similar at that of AZD4573 but at a higher dosage (15+15 mg/kg, 2 hours split, QW, IP). No adverse effects in mice were observed for any of treatments. Conclusion: These data show that our novel CDK9 inhibitor YX0798 is potent and efficacious in treating aggressive MCL models and overcame CAR-T resistance at a lower dosage than AZD4573. Citation Format: Vivian Jiang, Yu Xue, Hong Kim, Joseph McIntosh, Haiying Chen, Tianci Zhang, Yang Liu, Jia Zhou, Michael Wang. Targeting CDK9 with a novel potent and selective inhibitor, YX0798, in CAR-T-relapsed mantle cell lymphoma models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 602.

Abstract 3818: Sociodemographic, access to care and survival outcomes for patients with mantle cell lymphoma: A national cancer database analysis with focus on Hispanics

Abstract Background: Mantle cell lymphoma (MCL), represents 3% of new cases of non-Hodgkin’s lymphomas.(PMID 29348844) MCL affects mainly males; factors like ethnicity, age at presentation can have prognostic implications. Currently, it isn’t clear if Hispanics (HI) have a survival difference compared to Non-Hispanics (NH).(PMID 31029647, PMID 25315847). This National Cancer Database (NCDB) analysis aims to clarify how sociodemographic factors affect presentation and survival in HI vs NH patients with MCL. Methods: Data were analyzed on MCL patients in the United States reported to the NCDB 2004-2019. Demographic and treatment characteristics were compared between ethnic groups. Kaplan-Meier and Cox regression analyses were used to compare overall survival (OS). Multivariate analysis and propensity score matching was performed. Results: Of 32515 of MCL patients, 1729 were HI, and 29309 NH. Male gender and identification as white predominated for both. HI were diagnosed at a younger median age of 65 years (y) vs 68 y for NH, p<0.001. Most patients were diagnosed between years 2016-2019. Stage IV predominated for HI and NH, p<0.001. As to Charlson-Deyo Score ≥2, HI had 6% vs NH 8%. Government sponsored was the most prevalent primary payer, HI (54%) and NH (60%). HI had a higher percentage of unknown/uninsured, 13% vs 4% for NH, p<0.001. In relation to census median income (2008-2012), the most prevalent bracket for HI and for NH was >$63,000, 29% and 37% respectively. When analyzing median income of less than $38,000, HI were 22% vs 13% for NH, p<0.001. For median distance in miles (mi) between the patient’s residence and the hospital that reported the case (Great circle distance), HI lived at a median of 8.2mi, vs NH at median of 11.3mi. Most patients were treated at Academic/Research programs, 50% for HI and 39% for NH, p<0.001. On survival analysis, the survival probability at 2, 5 and 10 for HI was 74%, 57%, 44%, vs for NH was 72%, 54%, 36%, respectively. The median survival (MS) was 7.0 years for HI, vs 5.8 years for NH, with a statically significant difference in OS favoring HI, p=0.00015. On multivariate analysis, not insured status was independently associated with worse OS (HR 1.29, CI 1.08-1.55, p=0,01). The propensity matched analysis showed significant MS difference between HI vs NH (5.8 y vs. 5.6 y). Conclusion: In this analysis, MCL is a malignancy that presents at advanced stages, affecting mainly the elderly white males. HI compared to NH have a statically significant benefit in OS, which might be driven by a younger population with less comorbidities. Despite HI having limited access to insurance and lower income; sociodemographic differences don’t seem to be barriers for HI to access care at academic centers. Newer studies should focus on understanding what genetic and intrinsic disease factors cause HI to have an earlier presentation and a survival advantage over NH. Citation Format: Esteban Toro Velez, Carolina Velez-Mejia, Daniel Rosas, Qianqian Liu, Joel Michalek, Adolfo Enrique Diaz Duque. Sociodemographic, access to care and survival outcomes for patients with mantle cell lymphoma: A national cancer database analysis with focus on Hispanics [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3818.

Empowering macrophages: the cancer fighters within the tumour microenvironment in mantle cell lymphoma.

In Mantle Cell Lymphoma (MCL), the role of macrophages within the tumour microenvironment (TME) has recently gained attention due to their impact on prognosis and response to therapy. Despite their low absolute number in MCL tumour tissue, recent findings reveal an association between the levels of macrophages and prognosis, consistent with trends observed in other lymphoma subtypes. M2-like macrophages, identified by markers such as CD163, contribute to angiogenesis and suppression of the immune response. Clinical trials with MCL patients treated with chemoimmunotherapy and targeted treatments underscore the adverse impact of high levels of M2-like macrophages. Immunomodulatory drugs like lenalidomide reduce the levels of MCL-associated CD163+ macrophages and enhance macrophage phagocytic activity. Similarly, clinical approaches targeting the CD47 "don't eat me" signalling, in combination with the anti-CD20-antibody rituximab, demonstrate increased macrophage activity and phagocytosis of MCL tumour cells. Cell-based therapies such as chimeric antigen receptor (CAR) T-cell have shown promise but various challenges persist, leading to a potential interest in CAR-macrophages (CAR-M). When macrophages are recruited to the TME, they offer advantages including phagocytic function and responsiveness to microenvironment alterations, suggesting their potential as a manipulable and inducible alternative when CAR T-cell therapies fails in the complex landscape of MCL treatment.

The influence of marital status at diagnosis on survival of adult patients with mantle cell lymphoma

PurposeMarital status has been reported to influence the survival outcomes of various cancers, but its impact on patients with mantle cell lymphoma (MCL) remains unclear. This study aimed to assess the influence of marital status at diagnosis on overall survival (OS) and cancer-specific survival (CSS) in patients with MCL.MethodsThe study utilized data from the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER)-18 databases, including 6437 eligible individuals diagnosed with MCL from 2000 to 2018. A 1:1 propensity matching method (PSM) minimized confounding factor. Univariate and multivariate analyses determined hazard ratios (HR). Stratified hazard models were developed for married and unmarried statuses across time intervals.ResultsMarried patients exhibited better 5-year OS and CSS rates compared to unmarried patients (54.2% vs. 39.7%, log-rank p < 0.001; 62.6% vs. 49.3%, log-rank p < 0.001). Multivariate analysis indicated that being unmarried was an independent risk factor for OS (adjusted HR 1.420, 95% CI 1.329–1.517) and CSS (adjusted HR 1.388, 95% CI 1.286–1.498). After PSM, being unmarried remained an independent risk factor for both OS and CSS. Among unmarried patients, widowed individuals exhibited the poorest survival outcomes compared to patients with other marital statuses, with 5-year OS and CSS rates of 28.5% and 41.0%, respectively. Furthermore, in the 10-year OS and CSS hazard model for widowed individuals had a significantly higher risk of mortality, with the probability of overall and cancer-specific mortality increased by 1.7-fold and 1.6-fold, respectively.ConclusionMarital status at diagnosis is an independent prognostic factor for MCL patients, with widowed individuals showing worse OS and CSS than those who are married, single, or divorced/separated. Adequate psychological and social support for widowed patients is crucial for improving outcomes in this patient population.

TP53 mutation is frequent in mantle cell lymphoma with EZH2 expression and have dismal outcome when both are present

Enhancer of zeste homolog 2 (EZH2) expression is found in about 40% of mantle cell lymphoma (MCL) patients, which is associated with aggressive histology, high Ki-67 proliferation rate, p53 mutant pattern and inferior overall survival (OS). We conducted 11-gene (ATM, BIRC3, CCND1, KMT2C, KMT2D, NOTCH1, NOTCH2, RB1, TP53, TRAF2 and UBR5) next generation sequencing panel to shed more light on MCL with EZH2 expression (EZH2+ MCL). EZH2+ MCL more frequently harbor TP53 mutation compared to EZH2(−) MCL (41.2% vs. 19.1%, respectively, p = 0.045). TP53 mutation and EZH2 expression demonstrated overlapping features including aggressive histology, high Ki-67 proliferation rate and p53 mutant pattern by immunohistochemistry. Comparative analysis disclosed that EZH2 expression correlates with high Ki-67 proliferation rate irrespective of TP53 mutation. Aggressive histology is associated with EZH2 expression or TP53 mutation, possibly via independent mechanisms. p53 mutant pattern is due to TP53 mutation. MCL patients with EZH2 expression or TP53 mutation show inferior outcome and when both are present, patients have dismal outcome.

The dual HCK/BTK inhibitor KIN-8194 impairs growth and integrin-mediated adhesion of BTKi-resistant mantle cell lymphoma.

Although Bruton's tyrosine kinase (BTK) inhibitors (BTKi) have significantly improved patient prognosis, mantle cell lymphoma (MCL) is still considered incurable due to primary and acquired resistance. We have recently shown that aberrant expression of the Src-family tyrosine kinase hematopoietic cell kinase (HCK) in MCL correlates with poor prognosis, and that genetic HCK perturbation impairs growth and integrin-mediated adhesion of MCL cells. Here, we show that KIN-8194, a dual inhibitor of BTK and HCK with in vivo activity against Myd88-L265P-driven diffuse large B-cell lymphoma and Waldenström Macroglobulinemia, has a potent growth inhibitory effect in MCL cell lines and primary MCL cells, irrespective of their sensitivity to BTKi (ibrutinib and acalabrutinib). In BTKi-resistant cells this is mediated by inhibition of HCK, which results in repression of AKT-S6 signaling. In addition, KIN-8194 inhibits integrin-mediated adhesion of BTKi-sensitive and insensitive MCL cells to fibronectin and stromal cells in an HCK-dependent manner. Finally, we show that MCL cells with acquired BTKi resistance retain their sensitivity to KIN-8194. Taken together, our data demonstrate that KIN-8194 inhibits growth and integrin-mediated adhesion of BTKi-sensitive MCL cells, as well as MCL cells with primary or acquired BTKi resistance. This renders KIN-8194 a promising novel treatment for MCL patients.

Bendamustine as Lymphodepletion for Brexucabtagene Autoleucel Therapy of Mantle Cell Lymphoma

Brexucabtagene autoleucel (brexu-cel) is an autologous CD19-directed chimeric antigen receptor (CAR) T-cell therapy approved for treatment of relapsed/refractory mantle cell lymphoma (MCL). During a fludarabine shortage, we used bendamustine as an alternative to standard cyclophosphamide/fludarabine (cy/flu) lymphodepletion (LD) prior to brexu-cel. We assessed MCL patient outcomes as well as CAR T-cell expansion and persistence after brexu-cel following bendamustine or cy/flu LD at our center. This was a retrospective single institution study that utilized prospectively banked blood and tissue samples. Clinical efficacy was assessed by 2014 Lugano guidelines. CAR T-cell expansion and persistence in peripheral blood were assessed on day 7 and at ≥month 6 for patients with available samples. Seventeen patients received bendamustine and 5 received cy/flu. For the bendamustine cohort, 14 (82%) received bridging therapy and 4 (24%) had CNS involvement. Fifteen patients (88%) developed CRS with 4 (24%) ≥grade 3 events. Six (35%) patients developed ICANS with 4 (24%) events ≥grade 3. No patient had ≥grade 3 cytopenias at day 90. Best objective (BOR) and complete response (CRR) rates were 82% and 65%, respectively. At 24.5 months median follow-up, 12-month progression-free survival (PFS) was 45%, 24-month PFS was 25%, and median duration of response was 19 months. Median OS was not reached. BOR was 25% (1/4) for patients with CNS involvement. CAR transgene expansion after bendamustine LD was observed on day 7 in all (4/4) patients tested and persisted at ≥6 months (2/2), regardless of response. Bendamustine LD before brexu-cel for MCL is feasible and safe with a lower frequency and shorter duration of cytopenias than reported for cy/flu. Both CAR T-cell expansion and persistence were observed after bendamustine LD. Outcomes appear comparable to the real world outcomes reported with cy/flu LD.

Targeting DNMT3A-mediated oxidative phosphorylation to overcome ibrutinib resistance in mantle cell lymphoma

The use of Bruton tyrosine kinase (BTK) inhibitors such as ibrutinib achieves a remarkable clinical response in mantle cell lymphoma (MCL). Acquired drug resistance, however, is significant and affects long-term survival of MCL patients. Here, we demonstrate that DNA methyltransferase 3A (DNMT3A) is involved in ibrutinib resistance. We find that DNMT3A expression is upregulated upon ibrutinib treatment in ibrutinib-resistant MCL cells. Genetic and pharmacological analyses reveal that DNMT3A mediates ibrutinib resistance independent of its DNA-methylation function. Mechanistically, DNMT3A induces the expression of MYC target genes through interaction with the transcription factors MEF2B and MYC, thus mediating metabolic reprogramming to oxidative phosphorylation (OXPHOS). Targeting DNMT3A with low-dose decitabine inhibits the growth of ibrutinib-resistant lymphoma cells both invitro and in a patient-derived xenograft mouse model. These findings suggest that targeting DNMT3A-mediated metabolic reprogramming to OXPHOS with decitabine provides a potential therapeutic strategy to overcome ibrutinib resistance in relapsed/refractory MCL.

Selective pharmacologic targeting of CTPS1 shows single-agent activity and synergizes with BCL2 inhibition in aggressive mantle cell lymphoma.

Innovative therapeutic strategies have emerged over the past decade to improve outcomes for most lymphoma patients. Nevertheless, the aggressive presentation seen in high-risk mantle cell lymphoma (MCL) patients remains an unmet medical need. The highly proliferative cells that characterize these tumors depend on nucleotide synthesis to ensure high DNA replication and RNA synthesis. To take advantage of this vulnerability, STP-B, a clinically available small molecule selectively targeting CTP synthase 1 (CTPS1) has been recently developed. CTPS1 is a key enzyme of the pyrimidine synthesis pathway mediated through its unique ability to provide enough CTP in highly proliferating cells. Herein, we demonstrated that CTPS1 was expressed in all MCL cells, and that its high expression was associated with unfavorable outcomes for patients treated with chemotherapy. Using aggressive MCL models characterized by blastoid morphology, TP53 mutation or polyresistance to targeted therapies, we showed that STP-B was highly effective at nanomolar concentrations in vitro and in vivo, irrespective of these high-risk features. Inhibition of CTPS1 rapidly leads to cell cycle arrest in early S-phase accompanied by inhibition of translation, including of the anti-apoptotic protein MCL1. Consequently, CTPS1 inhibition induced synergistic cell death in combination with the selective BCL2 inhibitor venetoclax, both in vitro and in vivo. Overall, our study identified CTPS1 as a promising target for MCL patients and provided a mechanism-based combination with the BCL2 inhibitor venetoclax for the design of future chemotherapy-free treatment regimens to overcome resistance.

The Prognostic Role of Genetic Aberrations in Mantle Cell Lymphoma: A Literature Review and Clinical Experience

Mantle cell lymphoma (MCL) is a type of peripheral B-cell non-Hodgkin’s lymphoma characterized by constitutive cyclin D1 overexpression leading to cell-cycle dysregulation and disruption of DNA damage repair. Apart from the typical translocation t(11;14)(q13;q32) and more rare variants, such as t(2;11)(p11;q13) and t(11;22)(q13;q11), a considerable number of patients quite often show secondary molecular and chromosomal aberrations underlying heterogeneity of the clinical course of MCL. Among a wide range of molecular genetic abnormalities, particular attention during the last years has been concentrated on studying the so-called double-hit MCL within a subgroup of patients with translocations involving CCND1 and MYC genes. Double-hit MCL is distinguished with rapid progression and tumor generalization at the time of diagnosis. Poor prognosis and low survival rates in most MCL patients call for the fastest possible diagnosis. Morphological and immunohistochemical as well as genetic methods (standard cytogenetic technique and fluorescence in situ hybridization) contribute to improving the quality of evidence-based diagnosis. The results of comprehensive diagnostic studies optimize prognosis assessment and treatment decision making in clinic.

SENP3 Promotes Mantle Cell Lymphoma Development through Regulating Wnt10a Expression.

SUMO-specific protease 3 (SENP3), a member of the SUMO-specific protease family, reverses the SUMOylation of SUMO-2/3 conjugates. Dysregulation of SENP3 has been proven to be involved in the development of various tumors. However, its role in mantle cell lymphoma (MCL), a highly aggressive lymphoma, remains unclear. This study was aimed to elucidate the effect of SENP3 in MCL. The expression of SENP3 in MCL cells and tissue samples was detected by RT-qPCR, Western blotting or immunohistochemistry. MCL cells with stable SENP3 knockdown were constructed using short hairpin RNAs. Cell proliferation was assessed by CCK-8 assay, and cell apoptosis was determined by flow cytometry. mRNA sequencing (mRNA-seq) was used to investigate the underlying mechanism of SENP3 knockdown on MCL development. A xenograft nude mouse model was established to evaluate the effect of SENP3 on MCL growth in vivo. SENP3 was upregulated in MCL patient samples and cells. Knockdown of SENP3 in MCL cells inhibited cell proliferation and promoted cell apoptosis. Meanwhile, the canonical Wnt signaling pathway and the expression of Wnt10a were suppressed after SENP3 knockdown. Furthermore, the growth of MCL cells in vivo was significantly inhibited after SENP3 knockdown in a xenograft nude mouse model. SENP3 participants in the development of MCL and may serve as a therapeutic target for MCL.

Survival Outcomes of Patients with Mantle Cell Lymphoma: A Retrospective, 15-Year, Real-Life Study.

Mantle cell lymphoma (MCL) prognosis has significantly improved in recent years; however, the possible survival benefit of new treatment options should be evaluated outside of clinical trials. We investigated 73 consecutive MCL patients managed from 2006 to 2020. For younger patients <65 years old, the median PFS was 72 months and we reported a 2-year, 5-year, and 10-year PFS of 73%, 62%, and 41%; median OS was not reached and we reported a 2-year, 5-year, and 10-year OS of 88%, 82%, and 66%. For patients aged 75 years or older, the median PFS was 36 months and we reported a 2-year, 5-year, and 10-year PFS of 52%, 37%, and 37%; median OS was not reached and we reported a 2-year, 5-year, and 10-year OS of 72%, 55%, and 55%. The median PFS was significantly reduced for patients treated between 2006 and 2010 compared to patients treated between 2011 and 2015 (p = 0.04). Interestingly, there was a trend towards improved OS for patients treated between 2016 and 2020 compared to between 2006 and 2010 and between 2011 and 2015 (5-year OS was 91%, 44%, and 33%). These findings could be due to the introduction of BR as a first-line regimen for elderly patients and to the introduction of ibrutinib as a second-line regimen.

Real-world effectiveness and safety of ibrutinib in relapsed/refractory mantle cell lymphoma in Japan: post-marketing surveillance

Efficacy and safety data for ibrutinib in Japanese patients with relapsed/refractory (R/R) mantle cell lymphoma (MCL) were limited at the time of its approval in Japan. All-case post-marketing surveillance was conducted in Japanese R/R MCL patients who began ibrutinib treatment between December 2016 and December 2017, and patients were followed until 30 June 2020. In the effectiveness analysis set (n = 202), the overall response rate was 59.9%, 52-week progression-free survival was 47.5%, and overall survival was 69.3%. Safety was assessed in 248 patients (median age 74.0 years). When ibrutinib treatment was started, patients had received a median of three prior lines of therapy. The overall incidence of adverse events (AE) was 74.6%, and AE frequency and severity grade distribution were similar between patients with 1 versus more than 1 prior line of therapy. The most common AE was platelet count decreased (all grades; 10.4%), similarly to previous observations in patients with R/R chronic lymphocytic leukemia/small lymphocytic lymphoma. Five patients (2.0%) developed atrial fibrillation. The effectiveness and safety of ibrutinib were consistent with its known profile at approval in Japan. These results suggest that ibrutinib is effective and safe in Japanese R/R MCL patients in routine clinical practice.

Ibrutinib as first-line therapy for mantle cell lymphoma: a multicenter, real-world UK study

AbstractDuring the COVID-19 pandemic, ibrutinib with or without rituximab was approved in England for initial treatment of mantle cell lymphoma (MCL) instead of immunochemotherapy. Because limited data are available in this setting, we conducted an observational cohort study evaluating safety and efficacy. Adults receiving ibrutinib with or without rituximab for untreated MCL were evaluated for treatment toxicity, response, and survival, including outcomes in high-risk MCL (TP53 mutation/deletion/p53 overexpression, blastoid/pleomorphic, or Ki67 ≥ 30%). A total of 149 patients from 43 participating centers were enrolled: 74.1% male, median age 75 years, 75.2% Eastern Cooperative Oncology Group status of 0 to 1, 36.2% high-risk, and 8.9% autologous transplant candidates. All patients received ≥1 cycle ibrutinib (median, 8 cycles), 39.0% with rituximab. Grade ≥3 toxicity occurred in 20.3%, and 33.8% required dose reductions/delays. At 15.6-month median follow-up, 41.6% discontinued ibrutinib, 8.1% due to toxicity. Of 104 response-assessed patients, overall (ORR) and complete response (CR) rates were 71.2% and 20.2%, respectively. ORR was 77.3% (low risk) vs 59.0% (high risk) (P = .05) and 78.7% (ibrutinib-rituximab) vs 64.9% (ibrutinib; P = .13). Median progression-free survival (PFS) was 26.0 months (all patients); 13.7 months (high risk) vs not reached (NR) (low risk; hazard ratio [HR], 2.19; P = .004). Median overall survival was NR (all); 14.8 months (high risk) vs NR (low risk; HR, 2.36; P = .005). Median post-ibrutinib survival was 1.4 months, longer in 41.9% patients receiving subsequent treatment (median, 8.6 vs 0.6 months; HR, 0.36; P = .002). Ibrutinib with or without rituximab was effective and well tolerated as first-line treatment of MCL, including older and transplant-ineligible patients. PFS and OS were significantly inferior in one-third of patients with high-risk disease and those unsuitable for post-ibrutinib treatment, highlighting the need for novel approaches in these groups.

Immunoglobulin High Throughput Sequencing (Ig-HTS) Minimal Residual Disease (MRD) Analysis is an Effective Surveillance Tool in Patients With Mantle Cell Lymphoma

IntroductionMantle cell lymphoma (MCL) accounts for 4% to 6% of B-cell non-Hodgkin lymphoma with historically poor outcomes. With the advent of intensive first-line, targeted, and cellular therapies, outcomes have improved, and initial remission can be 8 to 10 years or longer. As patients experience longer remissions, this raises the question of the optimal surveillance modality. Peripheral blood minimal residual disease (MRD) analysis offers a potential alternative to surveillance imaging that is sensitive, less costly, and eliminates the risk of radiation exposure. Materials and MethodsThe clonoSEQ assay (Adaptive Biotechnologies) is an FDA-cleared commercially available Ig-HTS MRD assay with a sensitivity of 1 cell in 1,000,000. We performed a retrospective analysis of 34 patients from 2015 to 2021, who underwent MRD testing after achieving remission with first-line therapy. ResultsWith a median follow-up of 6.5 years, 10-year progression free survival (PFS) was 60% and 10-year overall survival was 92% of the entire cohort. Among 12 patients who sustained a radiographic relapse, peripheral blood became MRD+ either at or prior to the time of relapse in 11 patients (92%). The first MRD+ test had a lead time of 0 to 24 months (median 34 days) prior to radiographic relapse. Only 1 patient had a MRD− result while being found to have progressive disease on imaging. Among 22 patients who sustained continuous clinical remission, 21 have remained MRD−. Several patients were able to enjoy 2 to 4-year intervals without surveillance imaging. ConclusionsOur data suggest that the clonoSEQ MRD assay is an effective surveillance tool for MCL patients following first-line therapy and is predictive of relapse prior to imaging.

HSD39 Treatment Pathway and Unmet Needs of Mantle Cell Lymphoma Patients: An Exploratory Study from Portugal

HSD39 Treatment Pathway and Unmet Needs of Mantle Cell Lymphoma Patients: An Exploratory Study from Portugal

Long-term analysis of the RiBVD phase II trial reveals the unfavorable impact of TP53 mutations and hypoalbuminemia in older adults with mantle cell lymphoma; for the LYSA group.

Between 2011 and 2012, a phase II trial evaluated the use of the RiBVD (Rituximab, Bendamustine, Velcade and Dexamethasone) combination as first-line treatment for mantle cell lymphoma (MCL) patients aged over 65. We have now re-examined the classic prognostic factors, adding an assessment of the mutation status of TP53. Patients (n=74; median age 73 years) were treated with the RiBVD combination. Median Progression Free Survival (mPFS) was 79 months, and median Overall Survival (mOS) was 111 months. TP53 mutation status was available for 54/74 (73%) patients. TP53 mutations (TP53mt) were found in 12 patients (22.2%). In multivariate analysis, among the prognostic factors (PF) evaluated, only TP53mt and an albumin level below 3.6 g/dL (Alb<3.6 g/dL) were independently associated with a shorter mPFS. A hazard ratio (HR) of 3.16 (1.3-9.9, p=0.014) was obtained for TP53mt versus TP53wt, and 3.6 (1.39-9.5, p=0.009) for Alb<3.6 g/dL vs Alb≥3.6 g/dL. In terms of mOS, multivariate analysis identified three PFs: TP53mt (HR: 5.9 (1.77-19.5, p=0.004)), Alb<3.6 g/dL (HR: 5.2 (1.46-18.5, p=0.011)), and ECOG=2 (HR: 3.7 (1.31-10.6, p=0.014)). Finally, a score combining TP53 status and albumin level distinguished three populations based on the presence of 0, 1, or 2 PF. For these populations, mPFS was 7.8 years, 28 months and 2.5 months, respectively. Our prolonged follow-up confirmed the efficacy of the RiBVD regimen, comparing it favorably to other regimens. TP53mt and hypoalbuminemia emerge as strong PF that can be easily integrated into prognostic scores for older adult patients with MCL.