Rearrangements of MYC gene facilitate risk stratification in diffuse large B-cell lymphoma patients treated with rituximab-CHOP

Abstract

In order to address the debatable prognostic role of MYC rearrangements in diffuse large B-cell lymphoma patients treated with rituximab, cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisone, we evaluated MYC rearrangements by fluorescence in situ hybridization in 563 cases using break-apart probes and IGH/MYC dual-fusion probes. Concurrent BCL2 and BCL6 aberrations were also assessed. Data were correlated with clinicopathological variables and prognostic parameters. MYC rearrangements were observed in 39/432 evaluable cases (9%), including 4 rearrangements detectable only with the dual-fusion probes, 15 detectable only with the break-apart probes and 20 detectable with both dual-fusion probes and break-apart probes. MYC rearrangements correlated with germinal center B-cell origin (P ¼ 0.02), MYC protein expression (P ¼ 0.032), and larger tumor mass size (P ¼ 0.0003). Patients with MYC rearrangements were more likely to be treatment resistant (Po0.0001). All types of MYC rearrangements were associated with poorer disease-specific survival, that is, 20/39 dead, median disease-specific survival 42 months, compared with 98/393 dead among the nonrearranged cases, median disease-specific survival not reached (P ¼ 0.0002). Cases with MYC rearrangements that overexpressed MYC protein were at risk with respect to disease-specific survival independent of the International Prognostic Index (P ¼ 0.046 and Po0.001, respectively). Presence of concurrent BCL2 aberrations but not of BCL6 aberrations was prognostically additive. Radiotherapy seemed to diminish the prognostic effects of MYC rearrangements in diffuse large B-cell lymphoma patients since only 2/10 irradiated patients with MYC rearrangements died of/with disease, compared with 16/28 non-irradiated patients with MYC

Prognostic and biological significance of survivin expression in patients with diffuse large B-cell lymphoma treated with rituximab-CHOP therapy

“…Immunohistochemistry studies using antibodies for survivin (EP2880Y, Epitomics), p53 (DO-7, DAKO), pSTAT3 (EP2147Y, Abcam), Myc (clone Y69, Epitomics), Bcl-2 (Clone-124, DAKO), Ki-67 (MIB-1, DAKO), Blimp-1 (EPR16655, Epitomics), pAKT (726E11, CST), CD10 (56C6, Vantana), Bcl-6 (PG-B6p, DAKO), MUM1 (MUM1P, DAKO), and FOXP1 (EPR4113, Abcam) were performed using a streptavidin-biotin complex technique on 4 μm tissue microarray sections in all cases. [38][39][40][41][42][43][44] A list of antibodies and methods used for immunostaining are summarized in Supplementary Table S1. The formalin-fixed, paraffin-embedded tissue slides underwent deparaffinization and heatinduced antigen retrieval techniques.…”

Clinical features, tumor biology, and prognosis associated with MYC rearrangement and Myc overexpression in diffuse large B-cell lymphoma patients treated with rituximab-CHOP

“…15,24 In this study, we analyzed the occurrence of MYC translocation and Myc overexpression in GCB-and ABC-DLBCL (Figures 2a and b), and compared with the clinical features and tumor biology associated with these two overlapping biomarkers which have not been done by previous studies, and examined the dependence/independence between their indicated prognoses. To reduce the difference in Myc expression levels as a causing factor for the differential prognostic effect and tumor biology between MYC translocation and Myc overexpression activated by other mechanisms, the cutoff for Myc high was set at ≥ 70% in this study, which is the optimal cutoff for predicting MYC translocation according to previous studies.…”

“…The experimental techniques and scoring processes have been described previously. 15,21,24 Evaluation of other biomarker expression by immunohistochemistry was also performed on tissue microarray sections using corresponding antibodies: p53 (DO-7; Dako, Carpinteria, CA, USA), MDM2 (IF2; Calbiochem, Billerica, MA, USA), Bcl-2 (Clone-124; Dako), Ki-67 (MIB-1; Dako), pAKT (726E11; CST), Bcl-6 (PG-B6p; DAKO), FOXP1 (EPR4113; Abcam), MUM1/IRF4 (Dako), CD10 (56C6; Vantana), CD30 (clone BerH2; Dako), BLIMP-1 (EPR16655; Epitomics), NF-κB subunits (Dako), CXCR4 (Abcam, Cambridge, MA, USA), and survivin (EP2880Y; Epitomics). BCL6 and BCL2 translocations and TP53 mutations were detected as described previously.…”

“…BCL6 and BCL2 translocations and TP53 mutations were detected as described previously. 15,21,24,[35][36][37][38][39][40][41][42] Gene Expression Profiling Gene expression profiling for 457 patients was performed using the Affymetrix GeneChip Human Genome HG-U133 Plus 2.0 Array as described previously. 21,24,[35][36][37] The CEL files have been deposited in the National Center for Biotechnology Information Gene Expression Omnibus repository (GSE31312).…”

“…9,10 Several studies have reported that MYC translocations independently predicted significantly poor survival in DLBCL patients. [11][12][13][14][15][16] However, other studies found inconsistent results [17][18][19] or limitations of its prognostic significance. 20,21 The clinical significance of Myc overexpression in DLBCL has also been the source of much attention and controversy.…”