Alpha B crystallin was characterized as a negative prognostic factor in breast cancer. BCL2 has an antiapoptotic role and sustains cell survival in vitro, ironically BCL2 expression has been associated with a good prognosis of breast cancer patients. To investigate the significance of alpha B crystallin and BCL2 expression in breast cancer and the relationship between these proteins, we performed immunohistochemical staining for both proteins in human breast cancer tissues. In the present study, overexpression of alpha B crystallin was observed more frequently in triple negative cancer (9/20, 45%) than in luminal type cancer (8/53, 15.1%, P=0.02161). BCL2 tended to be more highly expressed in luminal type cancer than in HER2 and triple negative cancer types (luminal: 36/53, 68%, HER2: 2/9, 22%, triple negative: 7/20 35%, P=0.008652). In multivariate analysis using ANCOVA, alpha B crystallin was related to short overall survival (P=0.017173). These findings suggest that alpha B crystallin is an independent prognostic factor of infiltrating ductal carcinoma. BCL2 was not associated with survival in multivariate analysis using ANCOVA. Thus, in our study BCL2 was not an independent prognostic indicator.
Keywords: Alpha B crystallin; BCL2; breast cancer; overall survival.