The correlation between serum estrogen level and the expression of mismatch repair genes in colonic mucosa / 中华消化杂志

ABSTRACT

Objective To investigate the effects of estrogen on mismatch repiar gene expression in colonic mucosa in vivo. Methods A total of 42 healthy individuals underwent colonoscopy were enrolled in the study. Half an hour before colonoscopy examination, blood sample was taken for determining the serum estradiol (E2) level. N ormal colonic mucosal tissues determined by naked eye under colonoscopy examination were taken in the right hemi colon to detect HMLH1 and hMSH2 gene expression by semi-quantitative RT-PCR and immunohistochemistry staining. Then the correlation of serum E2 levels with hMLH1 and hMSH2 expression in colonic mucosa was analyzed. Results A bimodal curve was presented for the correlation between serum E2 level in healthy individuals and hMLH1 expression in colonic mucosa. A strong positive correlation of E2 level with hMLH1 expression in normal colonic mucosa was observed when serum E2 level was more than 45 pg/ml (For mRNA, P=0. 003, r=0. 701; for immunohistochemistry positivity index, P=0. 000, r=0. 874).However there was no correlation between E2 level and hMSH2 expression. Conclusion High serum E2 level might increase the hMLH1 gene expression in colonic mucosa in vivo.