Clinicopathologic correlation of autophagy-related Beclin-1 expression in gallbladder cancer

Autophagy plays critical roles in both cell survival and cell death. Beclin-1, a key modulator of autophagy function, is considered a haploinsufficient tumor suppressor. The role of Beclin-1 expression in cancer is still controversial. Some studies favor the idea that autophagy suppresses tumor development, whereas other researchers suggest that autophagy enhances tumorigenesis. The expression and function of Beclin-1 in gallbladder cancer (GBCA) remain largely unknown.

Methodology: We performed immunohistochemical staining for Beclin-1 in 119 GBCA cases, and investigated whether Beclin-1 expression correlated with clinicopathologic characteristics and prognosis of patients.

Beclin-1 was expressed in the cytoplasm of cancer cells with occasional nuclear staining in 53 (44.5%) of the 119 cases of GBCA with no expression in adjacent normal epithelial cells. Increased expression of Beclin-1 was significantly associated with longer survival rate of patients with GBCA in univariate (p=0.006) and multivariate analyses (p=0.005). There is no association between Beclin-1 expression and clinicopathologic characteristics.

Beclin-1 was highly expressed in GBCA, and positive expression in cancer cells was significantly related with favorable prognosis in GBCA patients. Our results suggest that the expression of Beclin-1 may be an independent predictive marker of favorable prognosis in GBCA.