Prognostic impact of diffuse large B-cell lymphoma with extra copies of MYC, BCL2 and/or BCL6: comparison with double/triple hit lymphoma and double expressor lymphoma.
ABSTRACT: BACKGROUND:The poor outcome of high-grade B-cell lymphoma, with rearrangements of MYC, BCL2 and/or BCL6, also known as double-hit lymphoma or triple-hit lymphoma (DHL or THL), has been well documented, while the clinical significance of extra copies of MYC, BCL2 or BCL6 are still less well known. METHODS:In total, 130 cases of diffuse large B-cell lymphoma, not otherwise specified (DLBCL-NOS) were included in our study. Fluorescence in situ hybridization and immunohistochemistry were performed in all cases to evaluate the genetic status and protein expression levels of MYC, BCL2 and BCL6. RESULTS:Among the 130 cases of DLBCL, the prevalence rates of extra copies of MYC, BCL2 and BCL6 were 10.8, 20.0 and 14.6%, respectively, and the corresponding rates of gene rearrangement were 10.0, 14.6 and 16.9%, respectively. In total, 7.7% (10/130) of patients were DHL/THL; 9.2% (12/130) of patients were DLBCL with MYC and BCL2 and/or BCL6 gene abnormalities including rearrangements or extra copies, while excluded DHL/THL. The positive protein expression rates of MYC, BCL2 and BCL6 were 46.9% (61), 75.4% (98) and 70.0% (91), respectively. Among the 51 cases with MYC/BCL2 co-expression, 14 cases showed concurrence of MYC, BCL2 and/or BCL6 genetic abnormalities, and the remaining 37 cases were classified as double-expressor lymphoma (DEL). MYC and BCL2 rearrangement and BCL2 extra copies were all associated with upregulated protein expression. Cases with concurrence of MYC, BCL2 and/or BCL6 genetic abnormalities were both associated with MYC/BCL2 co-expression. Patients with concurrence of MYC, BCL2 and/or BCL6 genetic abnormalities excluded DHL/THL had shorter OS (P?
Project description:Double/triple-hit lymphomas (DHL/THL) account for 5-10% of diffuse large B cell lymphoma (DLBCL) with rearrangement of MYC and BCL2 and/or BCL6 resulting in MYC overexpression. Despite the poor prognosis of DHL, R-CHOP chemotherapy remains the treatment backbone and new targeted therapy is needed. We performed comprehensive cytogenetic studies/fluorescence in situ hybridization on DLBCL and Burkitt lymphoma cell lines (n = 11) to identify the DHL/THL DLBCL in vitro model. We identified MYC/IG in Raji and Ramos (single hit); MYC/IG-BCL2 (DHL) in DOHH2, OCI-LY1, SUDHL2, and OCI-LY10; MYC/IG-BCL2/BCL6 (THL) in VAL; and no MYC rearrangement in U2932 and HBL1 (WT-MYC). Targeting MYC in the DHL/THL DLBCLs through bromodomain extra-terminal inhibitors (BETi) (JQ1, I-BET, and OTX015) significantly (p < 0.05) reduced proliferation, similar to WT-MYC cells, accompanied by decreased MYC but not BCL2 protein. Moreover, BETi suppressed MYC transcription and decreased BRD4 binding to MYC promoter in DHL cells. CD47 and PD-L1 are immunoregulatory molecules often expressed on tumors and regulated by MYC. High levels of surface CD47 but not surface PD-L1 was observed in DHL/THL, which was reduced by JQ1 treatment. BETi in combination with Pan-HDAC inhibitor had a limited effect on survival of DHL/THL, while combination of BETi and BCL2 inhibitor (ABT-199) had a significant (p < 0.005) inhibitory effect on survival followed by BCL-XL inhibition. Overall, the data suggests that MYC-expressing DLBCLs are probably addicted to the MYC-oncogenic effect regardless of MYC rearrangements. In summary, we identified an in vitro model for DHL/THL DLBCLs and provide evidence for the therapeutic potential of BET inhibitor alone or in combination with BCL2 inhibitor.
Project description:High-grade B-cell lymphoma (HGBL) with translocations involving MYC and BCL2 or BCL6 comprises ?10% of cases of diffuse large B-cell lymphoma (DLBCL) and carries a poor prognosis. The incidence, prognosis, and optimal therapy for DLBCL harboring extra copies of the genes MYC, BCL2, and BCL6, rather than their genetic translocations, are unknown. In this retrospective, single-center study we identified 144 DLBCL cases including 46 patients with classic HGBL with double-hit or triple-hit chromosomal translocations (DHL), 55 with extra copies of MYC in addition to aberrations (extra copies or translocations) of BCL2 and/or BCL6 but did not meet the criteria for HGBL (EC group), and 43 without any aberrations of MYC, BCL2, or BCL6 (wild type [WT]). Unfavorable baseline characteristics had similar frequency in the EC and WT groups, but were significantly more prevalent in the DHL group. With a median follow-up of 36 months, the 2-year event-free survival (EFS) was similar between the WT and EC groups at 77% (95% confidence interval [CI], 65-90) and 82% (95% CI, 72-93), respectively. In contrast, the 2-year EFS of the DHL group was 63% (95% CI, 51-79). The 2-year overall survival in the WT, EC, and DHL groups was 86% (95% CI, 76-97), 89% (95% CI, 81-98), and 74% (95% CI, 62-88), respectively. Among patients treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone), the EC group had outcomes similar to those of the WT group. Our results indicate that patients with DLBCL with extra gene copies of MYC, BCL2, and BCL6 fare differently from those with HGBL and respond well to standard R-CHOP therapy.
Project description:We investigated whether adding radiation (RT) to systemic therapy improved outcomes in early stage diffuse large B-cell lymphoma (DLBCL) patients with or without double- or triple-hit lymphoma (DHL/THL) biology. This analysis included 183 patients profiled with fluorescent in situ hybridization (FISH) for alterations in MYC, BLC2, and/or BCL6. A total of 146 (80%) were non-DHL/THL, 27 (15%) were DHL, and 10 (6%) were THL. Systemic therapy without RT resulted in inferior freedom from relapse (FFR) (HR: 2.28; 95% CI, 1.10-4.77; p?=?.02). The median FFR for non-DHL/THL was not reached and was 33 and 22.3 months for DHL and THL, respectively; p?<?.001. Low-risk (R-IPI <2) DHL/THL patients treated with rituximab-based therapy had 3-year FFR rates of 11% and 71% for systemic therapy without and with RT, respectively; p?=?.04. No differences in overall survival were observed between the treatment groups. Treatment intensification with RT may improve early stage DHL/THL outcomes.
Project description:Genomic alterations and protein expression levels have been established as prognostic factors for survival in patients with diffuse large B-cell lymphoma (DLBCL). In particular, double-hit DLBCL (DHL), which exhibits translocations in MYC and BCL2 and/or BCL6, is known to be associated with a poor prognosis. However, the clinical significance of gene alterations and protein expression levels for MYC, B-cell lymphoma (BCL)2, and BCL6 are unclear. In this study, we analyzed 61 adult patients diagnosed with DLBCL without DHL, who were treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone, or similar regimens. There were no differences in the distribution of MYC expression rates among the different MYC gene statuses. In log-rank tests, MYC translocation was a prognostic factor for overall survival (OS; P = 0.011), whereas BCL2 and BCL6 translocation were not prognostic indicators (P = 0.999 and P = 0.925, respectively). Although the expression levels of MYC and BCL6 were not significantly associated with OS, the expression of BCL2 was a prognostic factor for OS (P = 0.027). Furthermore, copy number gains in the MYC, BCL2, and BCL6 genes did not affect OS. MYC translocation (hazard ratio, 4.769; range, 1.518-14.98; P = 0.007) and BCL2 protein expression (hazard ratio, 3.072; range, 1.002-9.413; P = 0.049) were independent prognostic factors for survival in multivariate analyses. In conclusion, MYC translocation and BCL2 expression may need to be investigated at the initial diagnosis to predict prognosis in patients with DLBCL.
Project description:Double- and triple-hit lymphomas (DHL/THL) are aggressive B-cell neoplasms characterized by translocation of MYC with concurrent BCL2 and/or BCL6 translocation. In this retrospective study from one institution, we report clinicopathologic features of 13 cases (9 DHL/4 THL). The median age was 59 years (range 30-74) and patients included eight females and five males. Presentation included enlarging lymphadenopathy/masses (11 patients) and abnormal peripheral blood findings (2 patients). Features which raised the differential of an immature neoplasm included terminal deoxynucleotidyl transferase positivity (four cases, two THL/two DHL); dim CD45 expression (seven cases), lack of CD20 (two cases), or lack of surface immunoglobulin light chain (three cases) by flow cytometry; and blastoid morphology (two cases). We conclude that expression of TdT in a B-cell lymphoma with mature features or expression of surface light chain in a case otherwise suggestive of B-lymphoblastic leukemia/lymphoma should prompt an expedited evaluation for DHL/THL.
Project description:Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma (NHL), representing approximately 25% of diagnosed NHL. DLBCL is heterogeneous disease both clinically and genetically. The 3 most common chromosomal translocations in DLBCL involve the oncogenes BCL2, BCL6, and MYC. Double hit (DH) DLBCL is an aggressive form in which MYC rearrangement is associated with either BCL2 or BCL6 rearrangement. Patients typically present with a rapidly growing mass, often with B symptoms. Extranodal disease is often present. Though there is a paucity of prospective trials in this subtype, double hit lymphoma (DHL) has been linked to very poor outcomes when patients are treated with standard R-CHOP. There is, therefore, a lack of consensus regarding the standard treatment for DHL. Several retrospective analyses have been conducted to help guide treatment of this disease. These suggest that DA EPOCH-R may be the most promising regimen and that achievement of complete resolution predicts better long-term outcomes.
Project description:"Double-hit" lymphoma (DHL) is a high-grade B-cell lymphoma that harbors concurrent MYC and BCL2 or BCL6 rearrangements. Because cases of MYC/BCL6 DHL are uncommon, most reported conclusions have been based on cases of MYC/BCL2 DHL. Lack of experimental MYC/BCL6 DHL models continues to hinder the pathophysiologic and therapeutic investigations of this disorder. We herein describe a novel MYC/BCL6 DHL cell line, designated DH-My6, carrying both the MYC-IGH and BCL6-IGH fusion genes. Interruptions of MYC and BCL6 expressions using short interfering RNAs and chemical inhibitors led to significant attenuation of DH-My6 cell growth. Greater antitumor effects were found when the cells were treated with a combination of MYC and BCL6 inhibitors. Moreover, the PLK1 inhibitor volasertib and the HDAC inhibitor vorinostat synergized strongly when combined with the bromodomain inhibitor JQ1. DH-My6 is a new well-validated MYC/BCL6 DHL cell line that will provide a useful model for studies of the pathogenesis and therapeutics for the less common DHL tumor type. The rationale for approaches targeting both MYC and BCL6, and in combination with PLK1 or HDAC inhibitors for superior suppression of the aggressive MYC/BCL6 DHL warrants further in vivo testing in a preclinical model.
Project description:While MYC translocations in B-cell lymphoma (BCL) have been extensively studied, the significance of MYC amplification (MYC amp) is poorly understood. This study characterizes BCL showing MYC amp, defined as uncountable FISH signals. Retrospective analysis of all BCL FISH for MYC aberrations performed at our institution (1/2010-2/2018) identified 44/9715 (0.45%) cases with MYC amp. MYC amp probe signals appeared in a cloud-like distribution (70%) or in a single homogenous-staining-region (30%). In total 59% also had MYC separation by breakapart probe indicating concurrent MYC translocation. The most common morphology was large cell (82%) and diagnosis was diffuse large BCL (DLBCL, 50%). In total 88% were germinal center B-cell-like by Hans algorithm. In total 12/42 (29%) cases were "double-hit" by WHO criteria (DHL/THL) in addition to having MYC amp. The estimated 2-year overall survival (OS) of DLBCL cases with MYC amp was 80%. There was no significant difference in OS between DLBCL and DHL/THL among cases with MYC amp, suggesting a poor prognostic impact of MYC amp. However, when compared to a larger cohort of DLBCL and DHL/THL, MYC amp did not have prognostic significance. In summary, MYC amp in BCL is rare, most commonly occurs in DLBCL, and was not associated with survival in our cohort.
Project description:Double-hit lymphoma (DHL) is among the most aggressive and chemoresistant lymphoma subtypes. DHLs carry genomic abnormalities in MYC, BCL2, and/or BCL6 oncogenes. Due to the simultaneous overexpression of these driver oncogenes, DHLs are highly resistant to frontline therapies. Most DHLs overexpress both MYC and BCL2 driver oncogenes concurrently. We reasoned that simultaneous suppression of the two driver oncogenes would be more effective in eradicating DHLs than inactivation of single oncogene. XPO1 is a receptor for nuclear cytoplasmic transport of protein and RNA species. Recently, XPO1 inhibition was shown to downregulate MYC expression in several cancer cell lines. We therefore examined the role of XPO1 as a therapeutic target in suppressing MYC function and the potential synergistic effects of simultaneous suppression of XPO1 and BCL2 in the treatment of DHL. Here, we demonstrate that XPO1 inhibition abrogates MYC protein expression and induces massive tumor cell apoptosis. Combined use of XPO1 and BCL2 inhibitors is highly effective in eradicating DHL cells in cell culture. Notably, in a mouse model of DHL bearing primary tumor cells derived from lymphoma patients, combined treatment with XPO1 and BCL2 inhibitors blocks tumor progression, prevents brain metastasis, and extends host survival. Thus, our study confirms the simultaneous targeting of MYC and BCL2 driver oncogenes through the combined use of XPO1 and BCL2 inhibitors as a unique approach for the treatment of DHLs.
Project description:Recent studies provide convincing evidence that a combined immunohistochemical or fluorescence in situ hybridization (FISH) score of MYC, BCL2, BCL6 proteins and MYC translocations predicted outcome in diffuse large B-cell lymphoma (DLBCL) patients treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). However, by far, all these researches are based on Western populations. Therefore, we investigate the prognostic relevance of MYC-, BCL2- and BCL6-rearrangements and protein expression by immunohistochemistry and FISH from 336 de novo DLBCL, NOS treated with CHOP or R-CHOP. Breaks in MYC and BCL6, and fusion in IGH/BCL2 were detected in 9.7%, 20.0%, and 11.1% of the cases, respectively, and were not significantly associated with clinical outcomes. Protein overexpression of MYC (?40%), BCL2 (?70%) and BCL6 (?50%) was encountered in 51%, 51% and 36% of the tumors, respectively. On the basis of MYC, BCL2 and BCL6 expression, double-hit scores (DHSs) and triple-hit score (THS) were assigned to all patients with DLBCL. Patients with high MYC/BCL2 DHS, high MYC/BCL6 DHS and high THS had multiple adverse prognostic factors including high LDH level, poor performance status, advanced clinical stage, high International Prognostic Index (IPI) score, and non-germinal center B-cell. In univariate analysis, high MYC/BCL2 DHS, high MYC/BCL6 DHS and high THS were associated with inferior OS and PFS in both CHOP and R-CHOP cohorts (P<0.05). The highly significant correlations with OS and PFS were maintained in multivariate models that controlled for IPI (P<0.05). DLBCLs with high DHSs and high THS share the clinical features and poor prognosis of double-hit lymphoma (P>0.05). These data together suggest that the immunohistochemical DHSs and THS defined a large subset of DLBCLs with double-hit biology and was strongly associated with poor outcome in patients treated with R-CHOP or CHOP.