Abstract: To investigate the expression of α-B crystallin and its significance in breast carcinomas. MethodsTissue microarray and immunohistochemical methods were used to determine the expression of α-B crystallin and other markers (ER, PR, HER2 and Ki67) in 180 cases of breast invasive ductal carcinoma (IDC), 17 cases of ductal carcinoma in situ (DCIS) and 20 cases of normal breast tissue. These cases were grouped based on clinicopathological characteristics and molecular subtypes of breast carcinoma, and the different expressions of α-B crystallin in individual groups were evaluated. Results① The expressions of α-B crystallin between IDC (121/180, 67.22%) and DCIS (7/17, 41.17%) were significantly different (P＜0.05). ② The expressions of α-B crystallin were strongly associated with lymph node involvement (P＜0.01, r=0.368?8). ③ It was significantly different among those groups of the molecular subtype (P＜0.05). Among them, the P value was 0.0182 between the luminal A and the HER2+ groups and it was 0.0082 between the luminal A and the triple-negative groups. ConclusionThe expression of α-B crystallin in IDC is significantly higher than that in DCIS and is positively related to lymph node metastasis. There are also higher levels of expression in the HER2+ and the triple-negative groups. This suggests that α-B crystallin is involved in the process of progression and metastasis of breast cancer.

Key words: Breast neoplasm, α-B crystallin protein, Tissue microarray