Survival of patients with mantle cell lymphoma in the rituximab era: Retrospective binational analysis between 2000 and 2020

Conditional survival of younger patients with mantle cell lymphoma: Results from a randomized phase III trial of the European MCL Network

During a fatal disease, patients often request updated information on their prognosis. After patients have already survived a certain time, conditional survival captures their future survival probability. We investigated conditional overall and failure-free survival in 473 younger mantle cell lymphoma (MCL) patients from a randomized phase III trial comparing immunochemotherapies R-CHOP and alternating R-CHOP/R-DHAP before autologous transplantation. Using conditional Kaplan-Meier method and Cox regression, we estimated subsequent survival of patients who had survived 1-8 years, considering MIPI, Ki-67, and treatment failure status. Starting at a lower level, R-CHOP patients only showed increasing subsequent survival as they survived longer (5-year conditional survival: 72% and 81% after surviving 1 and 7 years), while R-CHOP/R-DHAP patients had stable future survival over time (77% and 78%). The prognostic value of MIPI diminished after 3 years in R-CHOP patients but remained unchanged after R-CHOP/R-DHAP. Patients with treatment failure had markedly inferior survival compared with those in ongoing remission, regardless of the time survived. The longer patients remained in remission, the longer they would stay free of treatment failures. Our results enable personalized counselling for younger MCL patients by offering dynamic prognosis and underscore the importance of highly effective first-line treatment to improve survival.

Effect of POD24 on the prognosis of follicular and other indolent B-cell non-hodgkin lymphomas

Indolent B-cell non-Hodgkin lymphomas(B-NHL) encompass a heterogeneous category of lymphomas characterized by a wide range of pathological subtypes. With the application of chemoimmunotherapy with rituximab (R-chemo), the prognosis of patients has improved considerably, with a 10-year survival rate of 60-80%. Despite these advancements, a significant number of patients still experience disease progression during or shortly after initial treatment. Those who progress within the first 24 months (POD24) continue to face a notably worse prognosis. This study aims to explore the significance of POD24 in predicting the prognosis of different subtypes of indolent B-cell NHL through a comprehensive literature review. The investigation extends to examining the existing prognostic assessment tools and evaluating the interrelationship between POD24 and these tools. By synthesizing relevant research findings, this study seeks to contribute to the current understanding of the role POD24 plays in prognostic evaluation and its potential implications in guiding clinical decision-making for patients with indolent B-cell NHL.

Front-line and second-line treatment for mantle cell lymphoma in clinical practice: A multicenter retrospective analysis

BACKGROUND

There are few reports of clinical practice treatment patterns and efficacy in mantle cell lymphoma (MCL).

MATERIALS AND METHODS

We retrospectively studied a large, multicenter, cohort of patients with MCL diagnosed between 2000 and 2020 in eight institutions.

RESULTS

536 patients were registered (73% male, median of 70 years). Front-line treatment was based on high-dose cytarabine, bendamustine, and anthracyclines in 42%, 12%, and 15%, respectively. The median PFS for all patients was 45 months; 68, 34, and 30 months for those who received high-dose cytarabine-based, bendamustine-based and anthracycline-based therapy. 204 patients received second-line. Bendamustine-based treatment was the most common second-line regimen (36% of patients). The median second-line PFS (sPFS) for the entire cohort was 14 months; 19, 24, and 31 for bendamustine-, platinum-, and high-dose cytarabine-based regimens, with broad confidence intervals for these latter estimates. Patients treated with cytarabine-based therapies in the front-line and those with front-line PFS longer than 24 months had a substantially superior sPFS.

CONCLUSION

Front-line treatment in this cohort of MCL was as expected and with a median PFS of over 3.5 years. Second-line treatment strategies were heterogeneous and the median second-line PFS was little over 1 year.

Death from mantle cell lymphoma limits sequential therapy, particularly after first relapse: Patterns of care and outcomes in a series from Australia and the United Kingdom

Mantle cell lymphoma (MCL) is a B-cell non-Hodgkin lymphoma characterised by a heterogeneous clinical course. Patients can often receive sequential treatments, yet these typically yield diminishing periods of disease control, raising questions about optimal therapy sequencing. Novel agents, such as chimeric antigen receptor T-cell therapies and bispecific antibodies, show promise in relapsed MCL, but are often reserved for later treatment lines, which may underserve patients with aggressive disease phenotypes who die early in the treatment journey. To assess the problem of patient attrition from lymphoma-related death limiting sequential treatment, we performed a multicentre retrospective cohort analysis of 389 patients treated at Australian and UK centres over a 10-year period. Deaths from MCL increased after each treatment line, with 7%, 23% and 26% of patients dying from uncontrolled MCL after first, second and third lines respectively. Patients with older age at diagnosis and early relapse after induction therapy were at particular risk of death after second-line treatment. This limitation of sequential treatment by lymphoma-related death provides support for the trial of novel therapies in earlier treatment lines, particularly in high-risk patient populations.

The USP35-CXCR3 Axis plays an oncogenic role in JeKo-1 mantle cell lymphoma cells

In B cells, the chemokine receptor CXCR3 is expressed only by a subset of B cells. However, CXCR3 is highly expressed in a rare type of B-cell lymphoma known as Mantle Cell Lymphoma (MCL) and CXCR3 inhibitor impairs proliferation and induces apoptosis in the MCL cell line JeKo-1. Despite this, the mechanism responsible for maintaining high levels of CXCR3 in MCL cells remains unclear. In this study, we assessed CXCR3 expression and amplification in MCL samples and confirmed that CXCR3 is overexpressed in MCL tissues. We also observed that CXCR3 amplification is present in a small portion of MCL patients and is associated with MCL classification. We then screened ubiquitin-specific proteases (USPs) that might control the degradation of CXCR3 protein. Our investigation revealed that USP35 acts as a potent stabilizer of CXCR3 protein. Knockdown of USP35 substantially reduced the CXCR3 protein levels in JeKo-1 cells, resulting in reduced cell viability, cell cycle arrest, increased apoptosis, and mitigated migration and invasion in these cells. At the molecular level, USP35 deubiquitinates and stabilizes CXCR3. USP35 deficiency attenuated the activation of the JAK1/STAT1 pathway and reduced the expression of β-catenin and c-Myc in JeKo-1 cells. Furthermore, we observed that overexpression of CXCR3 rescued the impaired tumorigenicity of USP35-deficient JeKo-1 cells, and the mechanism may be related to the fact that USP35 promotes CXCR3 deubiquitination to stabilize its expression. These findings collectively demonstrate the oncogenic role of the USP35-CXCR3 axis in JeKo-1 MCL cells.

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.

Resistance to PRMT5-targeted therapy in mantle cell lymphoma

ABSTRACT

Mantle cell lymphoma (MCL) is an incurable B-cell non-Hodgkin lymphoma, and patients who relapse on targeted therapies have poor prognosis. Protein arginine methyltransferase 5 (PRMT5), an enzyme essential for B-cell transformation, drives multiple oncogenic pathways and is overexpressed in MCL. Despite the antitumor activity of PRMT5 inhibition (PRT-382/PRT-808), drug resistance was observed in a patient-derived xenograft (PDX) MCL model. Decreased survival of mice engrafted with these PRMT5 inhibitor-resistant cells vs treatment-naive cells was observed (P = .005). MCL cell lines showed variable sensitivity to PRMT5 inhibition. Using PRT-382, cell lines were classified as sensitive (n = 4; 50% inhibitory concentration [IC50], 20-140 nM) or primary resistant (n = 4; 340-1650 nM). Prolonged culture of sensitive MCL lines with drug escalation produced PRMT5 inhibitor-resistant cell lines (n = 4; 200-500 nM). This resistant phenotype persisted after prolonged culture in the absence of drug and was observed with PRT-808. In the resistant PDX and cell line models, symmetric dimethylarginine reduction was achieved at the original PRMT5 inhibitor IC50, suggesting activation of alternative resistance pathways. Bulk RNA sequencing of resistant cell lines and PDX relative to sensitive or short-term-treated cells, respectively, highlighted shared upregulation of multiple pathways including mechanistic target of rapamycin kinase [mTOR] signaling (P < 10-5 and z score > 0.3 or < 0.3). Single-cell RNA sequencing analysis demonstrated a strong shift in global gene expression, with upregulation of mTOR signaling in resistant PDX MCL samples. Targeted blockade of mTORC1 with temsirolimus overcame the PRMT5 inhibitor-resistant phenotype, displayed therapeutic synergy in resistant MCL cell lines, and improved survival of a resistant PDX.

Do CAR-T and Allogeneic Stem Cell Transplant Both Have a Place in Lymphoid Neoplasms?

Allogeneic stem cell transplantation (allo-SCT) represented the first immunotherapy to treat hematologic malignancies: it has been considered as a cure for the disease and never as an approach to extend the life of patients. The success of allo-SCT derives both from the ability to treat patients with intensive chemoradiotherapy and from the potent graft-versus-leukemia effects mediated by donor immunity. Although considerable progress has been made in the last years, significant barriers still remain in the form of disease relapse, graft-versus-host disease, infectious complications, and regimen-related toxicities. Moreover, the treatment of hematologic malignancies, particularly acute lymphoblastic leukemia and certain forms of lymphomas, has been revolutionized by the commercial introduction of genetically modified autologous T-lymphocyte therapy (CAR-T). Our review discusses current standards and the shifting paradigms in the indications for allo-SCT and the role of CAR-T cell therapy for lymphoid neoplasms.