Abstract:

Objective: To evaluate Beclin-1 and Bcl-2 in the prognosis of non-small cell lung cancer (NSCLC) by analyzing the expression of the two markers and clinical/pathological characteristics of patients. Methods: A total of 120 paired cancerous and paracancerous tissue samples from NSCLC patients were collected from surgical procedures and expressions of Belin-1 and Bcl-2 protein was determined with immunohistochemical analysis. The correlation between Belin-1 and Bcl-2 and the clinical/pathological characteristics of the patients was studied. Results: The high expression rate of Beclin-1 in the paracancerous tissues was significantly higher than that in the cancer tissues (49.2% vs 31.7%, P<0.01), while Bcl-2 in paracancerous tissues was significantly lower than that in cancer tissues (21.7% vs 45.8%, P<0.01). The lower expression of Beclin-1 in NSCLC was associated with poor differentiation, advanced pathological stage and lymph node metastasis(P<0.05). Higher Bcl-2 expression rate was correlated with poor differentiation and lymph node metastasis (P< 0.05). Neither Beclin-1 or Bcl-2 expression in lung cancer tissues was associated with age, gender, smoking, preope-rative serum CEA and tumor pathological type (P>0.05). Multivariate Cox regression analysis showed that advanced pathological stage, the lower the expression of Beclin-1,and poor differentiation were independent predictors of poor prognosis in patients with NSCLC (P<0.05, P<0.01, P<0.01). In patients with high expression of Bcl-2, high Beclin-1 expression was related to a better 5-year survival (P<0.01). Conclusions: The fuction of autophagy activity in NSCLC is decreased. Lower Beclin-1 expression and higher expression of Bcl-2 are found in NSCLC tissues, and both of them are associated with occurrence and progress of NSCLC. High Beclin-1 may serve as a favorable prognostic marker independently for NSCLC patients with high Bcl-2 expression.

Key words: Beclin-1, Bcl-2, Prognosis, Non-small cell lung cancer