Study of Bcl2 Protein Expression in Experimental Colon Carcinoma Following Effects of Calendula Officinalis in Rats

Bcl-2 plays an important role in apoptosis regulation of solid tumors، such as colon and breast cancer. The purpose of this study is to determine bcl-2 expression on aberrantcrypt foci epithelial following treatment with Calendula officinalis extract. In this study، 56 male wistar rats with approximate age of 12 weeks and 200-300g weight wererandomly allocated into two equal groups (treatment & control). For induction of colorectal carcinoma these two groups were injected by 1، 2-dimethylhydrazine (40mg/kg) subcutaneously (2 injection/week for two weeks). Treatment group simultaneously received orally the Calendula officinalis extract (200mg/kg/day) for 10 weeks. After 10 weeks، tissue specimens were collected from distal parts of colon in both experimental groups and 3-4? m thick microscopic sections were prepared throughimmunohistchemistry staining method. Immunohistopathologi cal study revealed that expression of BCL2 protein in aberrant crypt foci of colon in treatment group in comparison with control group was lesser. Meandifference between two experimental groups was significant (p<0. 01). This in-vivo study indicated that BCL2 protein expression decreases in aberrant crypt foci epithelial cells of experimental colorectal carcinoma in rats following orally administration of Calendula officinalis extract.