Impact of Single or Combined Genomic Alterations of TP53, MYC, and BCL2 on Survival of Patients With Diffuse Large B-Cell Lymphomas: A Retrospective Cohort Study.
ABSTRACT: MYC and BCL2 translocations as well as TP53 deletion/mutation are known risk factors in diffuse large B-cell lymphoma (DLBCL) but their interplay is not well understood.In this retrospective cohort study, we evaluated the combined prognostic impact of TP53 deletion and mutation status, MYC and BCL2 genomic breaks in tumor samples of 101 DLBCL patients. The cohort included 53 cases with MYC rearrangements (MYC+).TP53 deletions/mutations (TP53+) were found in 32 of 101 lymphomas and were equally distributed between MYC+ and MYC- cases (35.8% vs. 27.1%). TP53+ lymphomas had lower responses to treatment than TP53- (complete remission 34.4% vs. 60.9%; P?=?0.01). TP53 alteration was the dominant independent prognostic factor in multivariate analysis (P?=?0.01). Overall survival (OS) varied considerably between subgroups with different genomic alterations: Patients with sole MYC translocation, and interestingly, with triple MYC+/BCL2+/TP53+ aberration had favorable outcomes (median OS not reached) similar to patients without genomic alterations (median OS 65 months). In contrast, patients with MYC+/BCL2+/TP53- double-hit lymphomas (DHL) (28 months), MYC+/BCL2-/TP53+ lymphomas (10 months) or sole TP53 mutation/deletion (12 months) had a poor median OS. Our findings demonstrate differences in OS of DLBCL patients depending on absence or presence of single or combined genetic alterations of MYC, BCL2, and TP53. Cooccurrence of TP53 and BCL2 aberrations ameliorated the poor prognostic impact of single TP53+ or BCL2+ in MYC positive patients.This pilot study generates evidence for the complex interplay between the alterations of genetic pathways in DLBCL, which goes beyond the concept of DHL. The variable survival of DLBCL patients dependent on single or combined alterations in the TP53, MYC, and BCL2 genes indicates the need for comprehensive genomic diagnosis.
Project description:Double hit lymphomas (DHL) and double expresser lymphomas (DEL) are subsets of diffuse large B cell lymphomas (DLBCL) which are being increasingly recognised as cause of treatment failure. This emphasizes the need for their separation from other DLBCL cases in order to prognosticate and administer more aggressive treatment to this set of patients. The present study was conducted with the aim to identify the DHL/DEL patients and study their distinctive clinicopathological profile and overall survival. This retrospective analysis involved 172 cases of DLBCL sub-classified on the basis of cell of origin. Immunohistochemical (IHC) analysis for <i>MYC, BCL2, BCL6, MUM1</i> and CD10 was performed. Rearrangement studies were performed using break apart Fluorescent in situ hybridization. Overall survival (OS) was also evaluated. Distinctive clinical and pathological features of DHL and DEL were identified. Rearrangement study by FISH revealed seven cases of DHL (<i>MYC </i>+ <i>BCL2</i> &/or <i>BCL6</i> rearrangement). Also, 20 patients (11.6%) showed a concurrent expression of <i>BCL2</i> and <i>MYC</i> oncoproteins (DEL) on IHC. Most (6/7) DHL patients were double expressors also. The DHL patients demonstrated a significant association with female gender, high serum LDH levels (> 750 U/L) and GCB phenotype. DEL patients contrarily predominated amongst males, had intermediate LDH levels (251-500 U/L) and non GCB phenotype. The OS of the patients was 63.8% at 4 years. The OS of the DLBCL, DEL and DHL patients was 71.9%, 46.9%, and 0%, respectively at 4 years (<i>p</i> value 0.010). In case of DEL subtype, factors such as age < 60 years (66.7%), male sex (60.8%), nodal localization (52.5%), early disease stage (84.6%), low IPI score (60%), absence of B symptoms (50%), LDH < 250 U/L (80%) and GCB phenotype (53.3%) were associated with better OS. Further, the OS of DHL cases was 0% at 4 years. Double hit and double expresser lymphomas have poor prognostic outcomes and should be separated from DLBCL. All DELs should be tested for DHLs and especially those with immunoblastic morphology. DHL and DEL subtypes delineate the subtypes with inferior OS and reinstate the need for aggressive interventions.
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:Concomitant deregulation of MYC and BCL2 comprises clinically significant, yet poorly characterized biological high-risk feature in diffuse large B-cell lymphoma (DLBCL). To interrogate these lymphomas, we analyzed translocations and protein expression of BCL2, BCL6, and MYC; correlated the findings with comprehensive mutational, transcriptomic, and clinical data in 181 patients with primary DLBCL; and validated the key findings in independent data sets. Structural variations of BCL2 were subtype-specific and specifically increased BCL2 expression. Molecular dissection of MYC deregulation revealed associations with other lymphoma drivers, including loss of TP53, and distinctive gene expression profiles. Double protein expression (DPE) arose from heterogeneous molecular backgrounds that exhibited subtype-dependent patterns. In the germinal center B-cell (GCB) DLBCL, concurrent alterations of MYC and BCL2 loci gave rise to the majority of DPE DLBCLs, whereas among the activated B-cell (ABC) DLBCLs, concurrent alterations were infrequent. Clinically, DPE DLBCL defined a prognostic entity, which was independent of the International Prognostic Index (IPI) and cell of origin, and together with the loss of TP53 had a synergistic dismal impact on survival. In the DPE DLBCL, the loss of TP53 was associated with a chemorefractory disease, whereas among the other DLBCLs, no correlation with survival was seen. Importantly, BCL6 translocations identified non-GCB lymphomas with favorable BN2/C1-like survival independent of IPI and concurrent DPE status. Taken together, our findings define molecular characteristics of the DPE in DLBCL, and recognize clinically feasible predictors of outcome. Given the emerging taxonomical significance of BCL2, BCL6, MYC, and TP53, our findings provide further depth and validation to the genomic classification of DLBCL.
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: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?<?0.001) than patients with DLBCL with no genetic change, and showed no statistical different with patients with DHL/THL (P?=?0.419). Extra copies of MYC was independent prognostic factors for DLBCL. CONCLUSIONS:Patients with MYC and BCL2 and/or BCL6 gene extra copies might show a trend towards poor prognosis, and the detection of extra copies of MYC, BCL2 and BCL6 might deserve more attention.
Project description:MYC translocations are the biologic hallmark of Burkitt lymphomas but also occur in other mature B-cell lymphomas. If accompanied by chromosomal breaks targeting the BCL2 and/or BCL6 oncogenes, these MYC translocation-positive (MYC+) lymphomas are called double-hit lymphomas (DHLs); otherwise, the term single-hit lymphoma (SHL) is applied. In order to characterize the biologic features of these MYC+ lymphomas other than Burkitt lymphomas, we explored, after exclusion of molecular Burkitt lymphoma (mBL) as defined by gene expression profiling (GEP), the molecular, pathological and clinical aspects of 80 MYC translocation (MYC+) lymphomas (31 SHL, 26 BCL2+/MYC+, 14 BCL6+/MYC+, 6 BCL2+/BCL6+/MYC+ and 3 MYC+ lymphomas with unknown BCL6 status). Comparison of SHL and DHL revealed no difference in frequency of MYC partner (IG/non-IG), genomic complexity or MYC expression and no differences in GEP. DHL showed a more frequent GCB-like GEP and higher IGH and MYC mutation rates. GEP revealed 130 differentially expressed genes between BCL6+/MYC+ and BCL2+/MYC+ DHL. BCL2+/MYC+ DHL showed a more frequent GCB-like GEP. Analysis of all lymphomas according to MYC partner (IG/non-IG) revealed no substantial differences. In contrast to mBL and lymphomas without MYC break, SHL and DHL patients had similar poor outcome. Our data suggest that after excluding mBL, MYC+ lymphomas could be biologically widely lumped without further need for subclassification. 32 diffuse large B-cell lymphoma samples were hybridized to HG-U133A Affymetrix GeneChips. In addition, this study contains 30 already published samples, which contribute to GSE4475 (Hummel et al. 2006 (PMID 16760442)), as well as 18 already published samples from GSE22470 (Salaverria et al. 2011 (PMID 21487109)). No re-normalisation of the published samples was performed. The complete dataset representing: (1) the 32 diffuse large B-cell lymphoma Samples, (2) the 30 Samples from GSE4475 and (3) the 18 Samples from GSE22470, is linked below as a supplementary file
Project description:Refractory/relapsed diffuse large B-cell lymphoma (DLBCL) is associated with poor outcome. The clinical behavior and genetic landscape of DLBCL is heterogeneous and still not fully understood. <i>TP53</i> mutations in DLBCL have been identified as markers of poor prognosis and are often associated with therapeutic resistance. Chimeric antigen receptor T-cell therapy is an innovative therapeutic concept and represents a game-changing therapeutic option by supporting the patient's own immune system to kill the tumor cells. We investigated the impact of <i>TP53</i> mutations on the overall survival of refractory/relapsed DLBCL patients treated with comparable numbers of therapy lines. The minimum number of therapy lines was 2 (median 4), including either anti-CD19 CAR T-cell therapy or conventional salvage therapy. A total of 170 patients with DLBCL and high-grade B-cell lymphoma with <i>MYC, BCL2,</i> and/or <i>BCL6</i> rearrangements (DHL/THL), diagnosed and treated in our hospital between 2000 and 2021, were included. Twenty-nine of them received CAR T-cell therapy. <i>TP53</i> mutations were found in 10/29 (35%) and 31/141 (22%) of patients in the CAR T-cell and conventional groups, respectively. Among the 141 patients not treated with CAR T cells, <i>TP53</i> mutation was an independent prognostic factor for overall survival (OS) (median 12 months with <i>TP53</i> vs. not reached without <i>TP53</i> mutation, <i>p</i> < 0.005), but in the CAR T cell treated group, this significance could not be shown (median OS 30 vs. 120 months, <i>p</i> = 0.263). The findings from this monocentric retrospective study indicate that <i>TP53</i> mutation status does not seem to affect outcomes in DLBCL patients treated with CAR T-cell therapy. Detailed evaluation in large cohorts is warranted.
Project description:A proportion of <i>MYC</i> translocation positive diffuse large B-cell lymphomas (DLBCL) harbour a <i>BCL2</i> and/or <i>BCL6</i> translocation, known as double-hit DLBCL, and are clinically aggressive. It is unknown whether there are other genetic abnormalities that cooperate with <i>MYC</i> translocation and form double-hit DLBCL, and whether there is a difference in clinical outcome between the double-hit DLBCL and those with an isolated <i>MYC</i> translocation. We investigated <i>TP53</i> gene mutations along with <i>BCL2</i> and <i>BCL6</i> translocations in a total of 234 cases of DLBCL, including 81 with <i>MYC</i> translocation. <i>TP53</i> mutations were investigated by PCR and sequencing, while <i>BCL2</i> and <i>BCL6</i> translocation was studied by interphase fluorescence in situ hybridization. The majority of <i>MYC</i> translocation positive DLBCLs (60/81 = 74%) had at least one additional genetic hit. In <i>MYC</i> translocation positive DLBCL treated by R-CHOP (<i>n</i> = 67), <i>TP53</i> mutation and <i>BCL2,</i> but not <i>BCL6</i> translocation had an adverse effect on patient overall survival. In comparison with DLBCL with an isolated <i>MYC</i> translocation, cases with <i>MYC/TP53</i> double-hits had the worst overall survival, followed by those with <i>MYC/BCL2</i> double-hits. In <i>MYC</i> translocation negative DLBCL treated by R-CHOP (<i>n</i> = 101), <i>TP53</i> mutation, <i>BCL2</i> and <i>BCL6</i> translocation had no impact on patient survival. The prognosis of <i>MYC</i> translocation positive DLBCL critically depends on the second hit, with <i>TP53</i> mutations and <i>BCL2</i> translocation contributing to an adverse prognosis. It is pivotal to investigate both <i>TP53</i> mutations and <i>BCL2</i> translocations in <i>MYC</i> translocation positive DLBCL, and to distinguish double-hit DLBCLs from those with an isolated <i>MYC</i> translocation.
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:Double hit lymphoma (DHL) and double protein-expressing (MYC, BCL2) lymphomas (DPL) fare poorly with R-CHOP (rituximab + cyclophosphamide, doxorubicin, vincristine, prednisolone); consolidative autologous stem cell transplant (ASCT) may improve outcomes. S9704, a phase III randomized study of CHOP +/-R with or without ASCT enabled evaluation of intensive consolidation. Immunohistochemistry (IHC) identified 27 of 198 patients (13·6%) with MYC overexpression; 20 (74%) harboured concurrent BCL2 overexpression. Four had DHL and 16 had DPL only. With median 127 months follow-up, there is a trend favouring outcomes after ASCT in DPL and MYC protein overexpressing patients, whereas all DHL patients have died irrespective of ASCT.