Effects of Neoadjuvant Chemotherapy on P-gp,GST-π Expression in Breast Cancer

Objective To explore the expression of P-gp and GST-π in breast cancer tissue receiving neoadjuvant chemotherapy and explore its clinical significance.Methods Expressions of P-gp;GST-π in 100 breast cancer patients before and after neoadjuvant chemotherapy were measured by immunohistochemistry Envision method.The relationship between P-gp,GST-π and the effect of neoadjuvant chemotherapy was analyzed by chi-square test.Results The overall response rate to neoadjuvant chemotherapy was 79%.In patients with P-gp,GST-π positive expression,the response rate to chemotherapy were 69.04%,and 77.08%,and in patients with P-gp,GST-π negative expression,the response rate to chemotherapy were 86.20%(P0.05) and 80.76%(P0.05).The positive expression of P-gp before and after chemotherapy were 41.75% and 64.83%,respectively,and their difference was statistically significant(P0.05).The positive expression of GST-π before and after chemotherapy were 49.45% and 54.94%,respectively,and no difference was found between them(P0.05).Conclusion The expression of P-gp increased significantly after neoadjuvant chemotherapy.It suggested that P-gp could be used to predict the therapeutic efficacy of neoadjuvant chemotherapy.