Expressions of bcl-2, programmed death-1 and programmed death ligand-1 in diffuse large B-cell lymphoma and their prognostic significances / 白血病·淋巴瘤

ABSTRACT

Objective:To investigate the expressions and correlation of bcl-2, programmed death-1 (PD-1) and programmed death ligand-1(PD-L1) in diffuse large B-cell lymphoma (DLBCL) tissue specimens, and the relationship between chemotherapy efficacy and prognosis of DLBCL patients.Methods:The expressions of bcl-2, PD-1 and PD-L1 in 82 patients with DLBCL who were admitted to Chenzhou First People's Hospital of Hunan Province from May 2011 to April 2014 were detected by using immunohistochemistry, and the correlation of the expressions of bcl-2, PD-1 and PD-L1 with clinicopathological characteristics and prognosis was analyzed.Results:The positive rate of bcl-2, PD-L1 and PD-1 in cancer tissues of DLBCL patients was 53.7% (44/82), 56.1% (46/82) and 32.9% (27/82), respectively. There was a correlation between bcl-2 and PD-L1 expression ( r = 0.306, P = 0.005). Bcl-2 was highly expressed in patients with international prognosis index (IPI) score 3-4 points, non-germinal center B-cell-like (non-GCB) subtype and B symptoms (all P < 0.05); PD-1 was highly expressed in patients with IPI score 3-4 points ( P < 0.05); PD-L1 was highly expressed in patients with IPI score 3-4 points, tumor stage Ⅲ-Ⅳ, B symptoms, ≥60 years old, and non-GCB (all P < 0.05). The overall survival (OS) and progression-free survival (PFS) in bcl-2-negative group were better than those in the bcl-2-positive group, and the differences were statistically significant (both P < 0.05); OS and PFS in PD-L1-negative group were better than those in PD-L1-positive group, and the differences were statistically significant(both P < 0.01). There were no statistical differences in OS and PFS between PD-1-positive group and PD-1-negative group (both P > 0.05). OS and PFS in bcl-2 and PD-L1 co-expression group were worse than those in both negative or any negative group (all P < 0.01), and PFS in bcl-2 and PD-1 co-expression group was worse than those in both negative or any negative group ( P = 0.044). Cox multivariate analysis showed IPI score 3-4 points and B symptoms were the independent influencing factors of OS in DLBCL patients (both P < 0.01); IPI score 3-4 points, B symptoms and PD-L1-positive were the independent influencing factors of poor PFS in DLBCL patients (all P < 0.05). Conclusion:The positive expressions of bcl-2 and PD-L1 are the independent factors for the poor prognosis of DLBCL patients, which may become new targets for the treatment of DLBCL.