RESUMO
Objective To understand the effect of estradiol in different concentrations on proliferation of diverse mammary primary cells in vitro. Methods The primary cells of cancer tissue, the adjacent tissue to tumors and normal mammary tissue from patiens with breast cancer were obtained using collagenase digesting method. All the tissue samples were cultivated in vitro, and were given estradiol in different concentrations. The effect of estradiol on the proliferation of those primary cells was measured by MTT. Results Estradiol remarkedly promoted the proliferation of primary cells of cancer tissue and peritumor tissue in vitro, whose ER expression were positive. Whereas, the promotion effect of estradiol on the proliferation of normal mammary primary cells was relatively weak, and there was no correlation between the promotion effect with the expression of ER in cancer tissue. Conclusion The risks of occurrence and relapse of breast cancer would increase significantly when the concentration of estradiol is no less than 103 pmol/L in vivo.