Phase 2 trial of rituximab and bortezomib in patients with relapsed or refractory mantle cell and follicular lymphoma

BACKGROUND:

In vitro studies in mantle cell lymphoma (MCL) cell lines and patient‐derived cells have demonstrated synergistic apoptosis with combined rituximab and bortezomib (R‐bortezomib) compared with single‐agent bortezomib. Therefore, the authors of this report evaluated R‐bortezomib in a preclinical model and in a phase 2 clinical trial.

METHODS:

A Hu‐MCL‐severe combined immunodeficiency (SCID) model engrafted with the Jeko cell line was treated with R‐bortezomib, bortezomib, or rituximab. Twenty‐five patients with relapsed follicular lymphoma (n = 11) and MCL (n = 14) received 375 mg/m² rituximab on Days 1 and 8 and 1.3 to 1.5 mg/m² bortezomib on Days 1, 4, 8, and 11 every 21 days for a median of 3 cycles (range, 1‐5 cycles).

RESULTS:

R‐bortezomib resulted in a statistically significant improvement in overall survival in Hu‐MCL‐SCID mice. In the clinical trial, the overall response rate was 40% in all 25 patients, 55% in patients with follicular lymphoma, and 29% in patients with MCL. The estimated 2‐year progression‐free survival (PFS) rate was 24% (95% confidence interval [CI], 10%‐53%) in all patients and 60% (95% CI, 20%‐85%) in responding patients. Thirteen patients (52%) developed grade 3 neurotoxicity, which consisted of constipation/ileus, sensory or motor neuropathy, or orthostatic hypotension. Patients who were heterozygous for the CD32a (Fcγ receptor IIa) 131 histidine (H) to arginine (R) polymorphism had a significantly decreased PFS (P = .009) after R‐bortezomib compared with HH and RR homozygotes.

CONCLUSIONS:

R‐bortezomib had significant activity in patients with relapsed or refractory follicular lymphoma and MCL, although an unexpectedly high incidence of grade 3 neurologic toxicity was a potential limiting factor with this combination. Cancer 2011. © 2010 American Cancer Society.     

The combination of bortezomib with enzastaurin or lenalidomide enhances cytotoxicity in follicular and mantle cell lymphoma cell lines

We analyzed the combination of a proteasome inhibitor (bortezomib) with enzastaurin (PKC/AKT‐inhibitor) or lenalidomide (immunomodulatory agent) for the inhibition of proliferation and induction of apoptosis in B‐cell lymphoma cell lines and primary malignant cells. The effects of bortezomib, enzastaurin or lenalidomide, alone or in combinations, on cell viability and apoptosis were evaluated using the Cell Proliferation Kit and flow cytometry analysis. The interaction between drugs was examined by the Chou–Talalay method. Cell cycle analysis was performed by flow cytometry. The PI3K/AKT, PKC and MAPK/ERK signaling pathways were analyzed using western blot. Bortezomib with either enzastaurin or lenalidomide synergistically induced anti‐proliferative and pro‐apoptotic effects in B‐cell lymphoma cells, even in the presence of the bone marrow microenvironment. The direct cytotoxicity is mediated by signaling events involving the PI3K/AKT, PKC and MAPK/ERK pathways leading to cell death. The significant increase of apoptosis was mediated by an increased ratio of pro‐apoptotic proteins (Bax, Bad and Bim) to anti‐apoptotic proteins (Bcl‐2, Bcl‐xL and Mcl‐1), triggering the cleavage of caspases ‐3, ‐9, ‐8 and PARP. Further evaluation of the combination of bortezomib with enzastaurin or lenalidomide for the treatment of B‐cell lymphoma is warranted, with the goal to improve the quality of life and survival of patients. Copyright © 2014 John Wiley & Sons, Ltd.     

Targeting the proteasome in mantle cell lymphoma: a promising therapeutic approach

Mantle cell lymphoma (MCL) is a distinctive non-Hodgkin's lymphoma sub-type, characterized by over-expression of cyclin D1 as a consequence of chromosomal translocation t(11;14)(q13;q32). MCL remains an incurable disease, combining the unfavorable clinical features of aggressive and indolent lymphomas. The blastic variant of MCL, which is often associated with additional cytogenetic alterations, has an even worse prognosis and new treatment options are clearly needed. The 26S proteasome is a large multi-catalytic multi-protein complex, present in all eukaryotic cells. It is responsible for the degradation of a variety of short-lived proteins and exhibits a key position in cellular processes including apoptosis and cell cycle progression. Targeting the ubiquitin - proteasome pathway has only recently been identified as a promising new therapeutic option for cancer patients. Interestingly, an increased activity of the proteasome pathway has been described in MCL cells and the inhibition of the proteasome seems to be a promising therapeutic approach for this incurable disease.     

套细胞淋巴瘤诊疗进展

套细胞淋巴瘤（mant lecell lymphoma ,MCL ）是一种少见的B 细胞非霍奇金淋巴瘤（non-Hodgkin's lymphoma,NHL ）类型,兼具有惰性淋巴瘤和侵袭性淋巴瘤的临床病理特点。目前MCL 的临床治疗仍然是以全身化疗为主,含有阿糖胞苷的强诱导化疗,随后行自体造血干细胞移植（autologous stem cell transplantation,Auto-HSCT ）巩固,可以显著延长生存期,但MCL 仍然属于不可治愈的淋巴瘤类型。近年来,随着对MCL 发病机制的深入研究,更多的新药如Btk抑制剂、PI 3K 抑制剂、免疫调节剂等在MCL 中得到应用。初治、复发难治MCL 都具有更多的治疗选择,如何将新药和现有的化疗更为有机的结合,更好的改善MCL 患者的生存期是未来研究的重点。     

Combination of hyperthermia and bortezomib results in additive killing in mantle cell lymphoma cells

The proteasome inhibitor bortezomib exhibits antitumor activity in many malignancies including mantle cell lymphoma (MCL). Unfortunately, many patients fail to respond to treatment or become refractory. Hyperthermia is an effective chemosensitizer that in combination with some chemotherapeutic agents has shown clinical activity in phase II and III studies. The aim of this study was to use MCL cell lines to investigate the potential benefit of combining clinically relevant doses of bortezomib with two different thermal doses (41.8°C/120 min and 44°C/30 min) that mimic the heterogeneity of the temperature distributions achieved within tumors during hyperthermia. Treated tumor cells were assessed for proliferation using the WST-1 assay and for apoptosis by annexin V staining, while heat shock protein (HSP) levels were determined following western blot analysis. Our results demonstrated that MCL cell lines that are sensitive to bortezomib are also thermosensitive and have low basal expression of hsp27, whereas the bortezomib-resistant MCL cell line strongly expresses hsp27 and is thermoresistant. Interestingly, pre-treatment of MCL cell lines with heat at the two different thermal doses, and the transient elevation of hsp27 and hsp70, do not impair their primary sensitivity to bortezomib. Finally, we show that the concurrent treatment of heat and bortezomib results in additive killing in MCL cell lines.In conclusion, these results suggest that the application of bortezomib, under thermal conditions, in mantle cell lymphoma cells may be beneficial and warrants further investigation.     

Leukemic involvement is a common feature in mantle cell lymphoma

BACKGROUND: The reported incidence of peripheral blood involvement in patients with mantle cell lymphoma (MCL) ranges from 13% to 77%. The aim of the study was to analyze the prevalence and the biologic and clinical significance of leukemic involvement in a series of patients with MCL. METHODS: Leukemic expression was assessed by conventional morphology and flow cytometry (FC) in 48 patients. In addition, comparative genomic hybridization (CGH) was performed in 27 patients. RESULTS: At diagnosis, 44 patients (92%) had evidence of leukemic expression by FC, including 8 patients (17%) without morphologically apparent leukemic involvement. Moreover, a lymphocyte count > or =5 x 10(9)/L was observed in 25 cases (52%). The most frequent imbalances detected by CGH were gains of 3q, 7p, 8q, 9q, 12q, and 13q, and losses of 13q, 1p, 9p, 11q, 10p, 17p, 6q, 8p, and 9q. Using a cutoff of 5 x 10(9)/L lymphocytes, cases with lymphocytosis more frequently presented with gains of 3q (P = .02), losses of 10p (P = .05), a low response rate (P = .04), and a short survival (P = .05). CONCLUSIONS: Leukemic expression at diagnosis detected by FC was found to be highly frequent in this series of patients with MCL. Although morphologically apparent leukemic expression was not associated with specific chromosomal alterations detected by CGH, a lymphocyte count > or =5 x 10(9)/L was correlated with particular genetic abnormalities and a poor outcome.     

Dual PI3K/mTOR inhibition is required to effectively impair microenvironment survival signals in mantle cell lymphoma

Phosphatidylinositol-3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway activation contributes to mantle cell lymphoma (MCL) pathogenesis and drug resistance. Antitumor activity has been observed with mTOR inhibitors. However, they have shown limited clinical efficacy in relation to drug activation of feedback loops. Selective PI3K inhibition or dual PI3K/mTOR catalytic inhibition are different therapeutic approaches developed to achieve effective pathway blockage. Here, we have performed a comparative analysis of the mTOR inhibitor everolimus, the pan-PI3K inhibitor NVP-BKM120 and the dual PI3K/mTOR inhibitor NVP-BEZ235 in primary MCL cells. We found NVP-BEZ235 to be more powerful than everolimus or NVP-BKM120 in PI3K/Akt/mTOR signaling inhibition, indicating that targeting the PI3K/Akt/mTOR pathway at multiple levels is likely to be a more effective strategy for the treatment of MCL than single inhibition of these kinases. Among the three drugs, NVP-BEZ235 induced the highest change in gene expression profile. Functional validation demonstrated that NVP-BEZ235 inhibited angiogenesis, migration and tumor invasiveness in MCL cells. NVP-BEZ235 was the only drug able to block IL4 and IL6/STAT3 signaling which compromise the therapeutic effect of chemotherapy in MCL. Our findings support the use of the dual PI3K/mTOR inhibitor NVP-BEZ235 as a promising approach to interfere with the microenvironment-related processes in MCL.     

The impact of SAMHD1 expression and mutation status in mantle cell lymphoma: An analysis of the MCL Younger and Elderly trial

The sterile alpha motif and histidine‐aspartic domain‐containing protein 1 (SAMHD1) has been demonstrated to predict the response to high‐dose cytarabine consolidation treatment in acute myeloid leukemia patients. Here, we evaluated SAMHD1 as potential biomarker for the response to high‐dose cytarabine in mantle cell lymphoma (MCL) patients. We quantified SAMHD1 protein expression and determined the mutation status in patients of the MCL Younger and Elderly trials (n = 189), who had received high‐dose cytarabine‐ or fludarabine‐based polychemotherapy. Additionally, we quantified SAMHD1 expression in B cell lymphoma cell lines and exposed them to cytarabine, fludarabine, and clinically relevant combinations. Across both trials investigated, SAMHD1 mutations had a frequency of 7.1% (n = 13) and did not significantly affect the failure‐free survival (FFS, P = .47). In patients treated with high‐dose cytarabine‐ or fludarabine‐containing regimes, SAMHD1 expression was not significantly associated with FFS or complete remission rate. SAMHD1 expression in B cell lymphoma cell lines, however, inversely correlated with their in vitro response to cytarabine as single agent (R = .65, P = .0065). This correlation could be reversed by combining cytarabine with other chemotherapeutics, such as oxaliplatin and vincristine, similar to the treatment regime of the MCL Younger trial. We conclude that this might explain why we did not observe a significant association between SAMHD1 protein expression and the outcome of MCL patients upon cytarabine‐based treatment.     

Radiotherapy in mantle cell lymphoma: A literature review

Mantle cell lymphoma (MCL) is a B-cell malignancy, comprising between 3% and 10% of all adult-onset non-Hodgkin lymphomas. MCL is considered incurable with current treatment modalities and most patients require multiple lines of treatment during their lifetime. MCL is very sensitive to radiotherapy (RT), even when delivered in low doses. In limited-stage MCL, RT can enable the de-escalation of systemic therapy. RT monotherapy is a valid option for frail patients. In advanced-stage disease, RT is very potent mode of palliation, even in heavily pretreated and chemo-resistant patients. Furthermore, it can provide a respite during which systemic treatment is unnecessary. In general, RT has a favorable toxicity profile and can be repeated as necessary for local relapse or distant disease. This effective, safe, and relatively inexpensive modality of therapy has been underutilized for patients with MCL. In this review, we will outline the use of RT for limited and advanced-stage disease and its potential application in combination with novel drugs.     

A phase II study of bortezomib in mantle cell lymphoma: the National Cancer Institute of Canada Clinical Trials Group trial IND.150.

BACKGROUND: We evaluated the activity and toxic effects of bortezomib in patients with mantle cell lymphoma. PATIENTS AND METHODS: Thirty patients, including 29 eligible patients, were enrolled; 13 had received no prior chemotherapy. The dose of bortezomib was 1.3 mg/m2 given on days 1, 4, 8 and 11 every 21 days. Response was assessed according to the International Workshop Criteria for non-Hodgkin's lymphoma and toxicity graded using the National Cancer Institute Common Toxicity Criteria version 2.0. RESULTS: There were 13 responding patients (46.4%; 95% confidence interval=27.5% to 66.1%), including one unconfirmed complete remission. The median response duration was 10 months. Response rates were similar in previously untreated (46.2%) and treated (46.7%) patients. Neurological toxicity and myalgia led to treatment discontinuation in 10 patients after two to seven treatment cycles. Five serious adverse events (including two deaths) associated with fluid retention were observed in the first 12 patients. We subsequently excluded patients with baseline effusions, dyspnea or edema; no further events were seen. CONCLUSIONS: Bortezomib is active in treating patients with mantle cell lymphoma. While cumulative neuromuscular toxic effects limited therapy duration and specific issues related to fluid retention require further evaluation, continued study of this drug in combination regimens is warranted.     

Novel targeted therapies for mantle cell lymphoma

Mantle cell lymphoma (MCL) is an aggressive B-cell malignancy characterized by short median survival despite intensive therapies. The clinical behavior of MCL may be due to the complex pathophysiology of the disease which includes its genetic hallmark, the chromosomal translocation t(11;14) resulting in aberrant expression of cyclin D1, alteration in the DNA damage response, and constitutive activation of key anti-apoptotic pathways such as phosphatidyl-inositol 3-kinase (PI3K)/Akt and nuclear factor-kB (NF-kB). Collectively, these changes result in cell cycle dysregulation and give rise to profound genetic instability. Given this complex pathophysiology, the limited number of options for patients with relapsed/refractory MCL, and the difficulty in achieving long-lasting remissions with conventional approaches, it is essential to explore new treatment options targeting the numerous dysregulated pathways that are operable in MCL. We have recently reported that milatuzumab, a fully humanized anti-CD74 monoclonal antibody (mAb), in combination with anti-CD20 mAbs has significant preclinical and clinical activity in MCL. Here we discuss these results, provide additional insights into milatuzumab-mediated MCL cell death, and report preliminary data on the activity of other targeted biologic agents including PCI-32765 and CAL-101 currently undergoing evaluation at our institution and others.     

miR-17-92 cluster-BTG2 axis regulates B-cell receptor signaling in mantle cell lymphoma

B-cell receptor (BCR) signaling is critically activated and stable for mantle cell lymphoma (MCL), but the underlying mechanism of the activated BCR signaling pathway is not clear. The pathogenic basis of miR-17-92 cluster remains unclear although the oncogenic microRNA (miRNA) miR-17-92 cluster is highly expressed in patients with MCL. We revealed that miR-17-92 cluster overexpression is partly dependent on SOX11 expression and chromatin acetylation of MIR17HG enhancer regions. Moreover, miR-17-92 cluster regulates not only cell proliferation but BCR signaling activation in MCL cell lines. To comprehensively identify miR-17-92 cluster target genes, we performed pulldown-seq, where target RNA of miRNA was captured using the biotinylated miRNA mimics and magnetic bead-coated streptavidin, and quantified using next-generation sequencing. The pulldown-seq identified novel miRNA target genes, including tumor suppressors such as BTG2 (miR-19b), CDKN2A (miR-17), SYNE1 (miR-20a), TET2 (miR-18, miR-19b, and miR-92a), TNFRSF10A (miR-92a), and TRAF3 (miR-17). Notably, the gene expression profile data of patients with MCL revealed that BTG2 expression was negatively associated with that of BCR signature genes, and low BTG2 expression was associated with poor overall survival. Moreover, BTG2 silencing in MCL cell lines significantly induced BCR signaling overactivation and cell proliferation. Our results suggest an oncogenic role of miR-17-92 cluster-activating BCR signaling throughout BTG2 deregulation in MCL. Furthermore, this may contribute to the prediction of the therapeutic efficacy and improved outcomes of MCL.     

套细胞淋巴瘤的诊治进展

套细胞淋巴瘤(MCL)是一组以t(11;14)和细胞周期蛋白D1阳性(cyclinD1 )过度表达为特征的侵袭性非霍奇金淋巴瘤(NHL),约占NHL发病的5%~8%,预后差,近期通过比较基因组杂交(CGH),基因芯片和蛋白质组分析等研究MCL取得令人关注的进展。化疗 利妥昔治疗使治疗有效率较前明显提高,异体或自体干细胞移植亦使MCL的预后大为改善,新的治疗方案如蛋白酶体抑制剂硼替佐米(borte-zomib),反应停 利妥昔,细胞周期依赖激酶抑制剂(flavopridol)及哺乳动物雷帕霉素靶蛋白(mTOR)抑制剂CCI-779等的疗效令人鼓舞。     

112 例套细胞淋巴瘤临床病理分析*

目的：探讨套细胞淋巴瘤（mantle cell lymphoma,MCL ）的临床病理特点。方法：收集112 例MCL 的临床及病理资料,采用免疫组织化学（Envision二步法）行相关抗体标记,荧光原位杂交技术（fluorescence in situ hybridization,FISH）对其中24例作IgH/CCND1 基因断裂检测。结果：112 例（包括2 例多形性和母细胞变亚型）均表达B 细胞相关抗原,94.6%（106/112）表达cyclinD1,92.9%（104/112）表达CD5。不同免疫表型的经典型MCL 的Ki-67及平均生存期无统计学差异（P>0.05）。 3 例CD5-的MCL未检测出IgH/CCND1 基因断裂,2 例经典型MCL 检测出IgH/CCND1 多倍体。结论：MCL 是一种具有特殊免疫表型的B 细胞淋巴瘤,多形性及母细胞变异型的预后较差,对特殊亚型的MCL 诊断有必要细分。     

An overlapping case of in situ mantle cell neoplasia and leukemic non-nodal mantle cell lymphoma

In situ mantle cell neoplasia (isMCN) and leukemic non-nodal mantle cell lymphoma (nnMCL) are classified as an indolent subtype of mantle cell lymphoma (MCL). The tumor cells of isMCN are restricted to the inner layer of the lymphoid tissue mantle zone, exhibiting an in situ pattern histologically. On the other hand, nnMCL is distributed in the peripheral blood, bone marrow and sometimes the spleen, but lymphadenopathy or systemic organ involvement is rare. We report a case of isMCN in a submandibular lymph node resected from a 65-year-old Japanese male. The tumor cells were positive for cyclin D1 (CCND1) and SOX11 expression, and were restricted to the mantle zone area of the lymph node. However, tumor cells were also detected in the stomach mucosa, bone marrow tissue and peripheral blood, suggesting nnMCL. isMCN and nnMCL may have a partly overlapping disease spectrum, although the correlation between these two subtypes has not been well described. This present case demonstrated characteristics overlapping between isMCN and nnMCL.     

Proteasome inhibition with bortezomib: a new therapeutic strategy for non-Hodgkin's lymphoma

The incidence of non-Hodgkin's lymphoma (NHL) has markedly increased in the US and other westernized countries in recent years and presents a considerable clinical challenge. NHL is divided into subtypes that follow an aggressive or indolent course. Follicular lymphoma (FL), the most common indolent subtype, and mantle cell lymphoma (MCL), an aggressive subtype that accounts for approximately 5% of cases, are generally incurable. MCL has a relatively poor prognosis, with a median survival of 3-4 years. Despite improving response rates with new agents and regimens, the lack of demonstrated improvement in overall survival in many subtypes supports the development of novel approaches, such as proteasome inhibition. Bortezomib is the first proteasome inhibitor to be evaluated in human studies. It has already been approved as second-line treatment in multiple myeloma and is now under active investigation in NHL. The US FDA has granted bortezomib fast-track designation for relapsed and refractory MCL. In vitro and in vivo studies have demonstrated single-agent activity against various lymphoid tumors, and additive or synergistic effects in combination with other agents, including standard chemotherapy drugs employed in NHL. Phase 2 clinical trials indicate that bortezomib is well tolerated and active in several NHL subtypes, with response rates of 18-60% in FL and 39-56% in MCL. A number of combination trials are currently underway with a range of standard agents. Bortezomib has the potential to play a significant role throughout the NHL treatment algorithm in the future.     

miR-150在套细胞淋巴瘤中的表达及意义

  目的   探讨套细胞淋巴瘤（mantle cell lymphoma,MCL）中miR-150的表达情况及其临床意义。   方法   通过定量RT-PCR检测29例初治MCL患者及7例正常人外周血B细胞中miR-150和c-Myc的表达水平,探索miR-150和c-Myc表达之间的关系;利用RNAi阻断MCL细胞系Mino和HBL-2中c-Myc表达后,检测miR-150的变化,确定c-Myc是否参与miR-150的表达调控;抑制P493-6细胞表达c-Myc后,观察miR-150的变化,进一步明确miR-150是否受c-Myc调节;将pre-miR-150电转HBL-2细胞系,通过集落形成试验明确miR-150对细胞增殖的影响,Western blot检测c-Myb蛋白的变化。   结果   与正常人外周血B细胞相比,MCL患者低表达miR-150、过表达c-Myc,两者的表达呈负相关;阻断c-Myc后,Mino和HBL-2细胞的miR-150表达增加;抑制c-Myc表达后,P493-6细胞的miR-150表达增高;过表达miR-150后,HBL-2的c-Myb蛋白表达水平和集落形成能力下降。   结论   MCL患者低表达miR-150的原因可能与其c-Myc过表达有关。miR-150能够抑制MCL的增殖,在MCL的治疗中具有潜在价值。      

Intensive therapy with peripheral stem cell transplantation in 16 patients with mantle cell lymphoma

Background: Despite improved detection of mantle cell lymphoma (MCL),results of its treatment with conventional therapies remain disappointing andthe survival rate poor. The role of high-dose chemotherapy has recently beeninvestigated but no potential benefit has been clearly established. We reporthere our experience with MCL patients treated with intensive chemotherapy andautologous stem cell transplantation (ASCT).Patients and methods: Of the 16 MCL patients who received high-dosechemotherapy and ASCT beginning in 1989, six were treated in first-line and10 in sensitive relapse. Twelve of 16 patients received regimens whichincluded total body irradiation. All patients received peripheral blood stemcells (PBSC) with the exception of one, who underwent bone marrowtransplantation.Results: Three patients died of toxic effects of treatment. Three monthsafter transplant, seven achieved complete responses (CR) and two partialresponses (PR), two were stable and two had progressed. With a medianfollow-up after transplant of 22 months, five of the six surviving patientswere without progression, and three were in CR. The median times forevent-free survival (EFS) and overall survival (OS) were, respectively, 249and 317 days. The expected three-year EFS and OS were 24%. The mediansurvival after diagnosis was only 29 months. None of the criteria appeared tobe significantly associated with a better outcome, but first-lineintensification and a short delay after initial diagnosis may be favorable.Conclusion: In this study we were not able to confirm the hypotheticalbenefit of high-dose chemotherapy and PBSC transplantation in mantle celllymphoma, even though this approach may be promising in a subgroup of patient.