Relationship between pit patterns of colorectal polyps and expression of insulin-like growth factor-1 receptor in polyps

Abstract

Objective To investigate the relationship between the expression of insulin-like growth factor-1 receptor (IGF-1 R) and the pit patterns of colorectal polyps,and discuss its clinical significance.Methods The totals of 47 colorectal polyps were collected from patients undergoing colonoscopy polypectomy.The pit patterns were classified according to the Kudo classification scheme.Immunohistochemistry was employed to detect the expression of IGF-1R.Spearman' s rank correlation analysis was utilized to demonstrate the relationship between the pit patterns and the expression of 1GF-1 R.Results In 47 colorectal polyps,8 polyps showed type Ⅱ pit pattern,6 polyps type Ⅲ L,30 polyps type Ⅳ,and 3 polyps type V.Most of the polyps with type Ⅱ pit pattem were negative for the expression of IGF-1R.The polyps with type Ⅳ or type V pit pattern showed up-regulated expression of IGF-1 R.The polyps with type Ⅲ L pit pattern showed moderate IGF-1 R expression.The pit pattern of polyps showed a significant correlation with the level of IGF-1 R expression (rs =0.432,P ＜ 0.05 ).Conclusion The expression of IGF-1R may affect the proliferation and anti-apoptosis of epithelia,which causes the morphological change of colorectal mucosal crypt.This result suggests that the over-expression of IGF-1R is related with the neoplastic initiation of colorectal cancer and can be used for evaluation of the risk of carcinogenesis. Key words: Colorectal polyps; Pit pattern; Insulin-like growth factor 1 receptor; Colorectal epithelial crypt; Colorectal carcinoma