Bcl-2 protein frequency in patients with high-risk diffuse large B-cell lymphoma.
OBJECTIVE
Gene expression and immunohistochemical profiling of diffuse large B-cell lymphoma (DLBCL) have revealed important prognostic subgroups: germinal center B-cell-like (GCB-like) DLBCL and activated B cell-like (ABC-like) DLBCL. Although few reports on high-risk DLBCL are available, the prognosis for the GCB-like subgroup has been shown to be better than that of the ABC-like subgroup. The role of Bcl-2 as a predictor of survival in DLBCL cases is unclear and its expression varies between the two subgroups of DLBCL. In this study, we analyzed the frequency and prognostic impact of Bcl-2 protein expression in high-risk DLBCL cases.


METHODS
Retrospective cohort study among DLBCL patients treated at Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP).


METHODS
The prognostic impact of the expression of the proteins CD10, Bcl-6, MUM1 (multiple myeloma oncogene-1) and Bcl-2 on high-risk DLBCL cases was evaluated by means of immunohistochemistry. Seventy-three patients aged 18-60 years were evaluated for all these markers.


RESULTS
Twenty-four cases (32.9%) were GCB-like and 49 (67.1%) were ABC-like, with no difference regarding complete remission, disease-free survival or overall survival rates. Twenty-seven patients (37%) showed Bcl-2 expression, which was the only independent factor predicting a worse prognosis for overall survival according to multivariate analysis.


CONCLUSIONS
Bcl-2 protein was expressed in 37% of the high-risk DLBCL patients, without any difference between the ABC-like DLBCL and GCB-like DLBCL cases.
Department of Hematology, Universidade Federal de Juiz de Fora, Juiz de Fora, Brazil. abrahallack@uol.com.br
Abrahão Elias
AE
Hallack Neto
Sheila Aparecida Coelho
SA
Siqueira
Frederico Luiz
FL
Dulley
Alfredo
A
Chauobah
Marcelo
M
Belesso
Rosaura
R
Saboia
Milton Artur
MA
Ruiz
Dalton Alencar Fischer
DA
Chamone
Juliana
J
Pereira
D000293:Adolescent; D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism*; D016009:Chi-Square Distribution; D015331:Cohort Studies; D004268:DNA-Binding Proteins / Q000378:metabolism; D018572:Disease-Free Survival; D005260:Female; D015870:Gene Expression; D018858:Germinal Center / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D016403:Lymphoma, Large B-Cell, Diffuse / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009194:Myeloma Proteins / Q000378:metabolism; D015260:Neprilysin / Q000378:metabolism; D011379:Prognosis; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D051560:Proto-Oncogene Proteins c-bcl-6; D012189:Retrospective Studies; D055815:Young Adult
C084103:BCL6 protein, human; D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; D009194:Myeloma Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051560:Proto-Oncogene Proteins c-bcl-6; C085016:multiple myeloma M-proteins; D015260:Neprilysin