THE EXPRESSION OF BCL-2 AND BAX PROTEINS IN GASTRIC CARCINOMA AND PRECANCEROUS LESIONS

Objective To investigate the variance of expression of bcl-2 and bax genes in the genesis or gastric carcinoma as well as their relationship. Methods Thirty-five cases of early-stage gastric carcinoma and Twenty-four cases ot chronic atrophic gastritis were studied by immunohistochemical method. Results There were no statistical differences of bcl-2 expression levels between gastric carcinoma and atypical hyperplasia or paracancerous intestinal- epithelial metaplasia(IEM) (P>0.05).There were statistical differences of bcl-2 expression between normal epithe- lial tissues (or non-cancerous IEM) and the other three groups(P<0.05), but no statistical difference between the normal epithelial and the non-cancerous IEM group was observed(P>0.05). The expressions or bax protein were found in the normal epithelial and the other groups in varying degrees,but there were no statistical differences be- tween either two of the groups (P>0.05). The bcl-2/bax ratio was higher in early-stage gastric carcinoma,atypical hy- perplasia and paracancerous intestinal-metaplasia than in the non-cancerous intestinal-metaplasia (P<0.05) and nor- mal epithelial tissues(P<0.01). Conclusion The abnormal expression of bcl-2 protein and bax protein,especially the increased bcl-2/bax ratio, probably play an important role in the course of carcinogenesis or gastric carcinoma.