Expression and Significance of Beclin-1 and Bcl-2 in Gastric Cancer

Author(s): Mei Lin, Wenmin YUAN, Xiaohui SUN, Zhiqiang QIN

Objective To investigate the role and correlation of Beclin-1 and Bcl-2 in the occurrence and progression of gastric cancer. Methods The expression of Beclin-1 and Bcl-2 in 78 cases of gastric cancer, 30 cases of atypical hyperplasia and 20 cases of chronic non-atrophic gastritis was examined by immunohistochemical staining. Results The positive rate of Beclin-1 in gastric cancer was significantly lower than those in atypical hyperplasia and chronic non-atrophic gastritis(χ2=9.298,7.437, P<0.05), while there was no significant difference between atypical hyperplasia and chronic non-atrophic gastritis (P>0.05). The positive rate of Bcl-2 in gastric cancer was significantly higher than those in atypical hyperplasia and chronic non-atrophic gastritis(χ2=11.013, 15.278, P<0.05), while Bcl-2 expression in atypical hyperplasia showed no significant difference with that in chronic non-atrophic gastritis (P>0.05). The expression of Beclin-1 and Bcl-2 was significantly correlated with differentiation, depth of invasion and TNM staging(χ2=7.014~16.248, P>0.05), but not correlated with sex, age, tumor size, tumor location and metastasis(P>0.05). The expression of Beclin-1 was negatively correlated with Bcl-2 in gastric cancer(r=-0.396, P<0.01). Conclusion Beclin-1 expression was decreased and Bcl-2 expression was increased in gastric cancer. Both were associated with the occurrence and progression of gastric cancer and they were negatively correlated. Beclin-1 and Bcl-2 may be used as important markers to predict the biological behavior of gastric cancer.

gastric cancer, Beclin-1, Bcl-2, autophagy, apoptosis

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