Correlation of expression of Survivin, BCRP and HER-2 genes with therapeutic response of TE regimen neoadjuvant chemotherapy in breast cancer patients

Abstract

To study the changes of expression of Survivin mRNA, BCRP mRNA and HER-2 mRNA in breast cancer after TE regimen neoadjuvant chemotherapy, and to find biological markers to predict the efficiency of TE regimen neoadjuvant chemotherapy. The gene expressions were detected by RT-PCR from 56 breast cancer patients before and after TE regimen neoadjuvant chemotherapy (docetaxel and epirubicin). The relationships between these gene expressions and chemotherapy responses were analyzed. The overall response rate to neoadjuvant chemotherapy was 71.4%, including 8.9% (5/56) with complete response and 62.5% (35/56) with partial response. Pathological complete response was found in 4 cases (7.1%). Stable disease and progression of disease were 23.2% (13/56) and 5.4% (3/56), respectively. The expression of Survivin mRNA after neoadjuvant chemotherapy was 35.7% (20/56), significantly lower than 60.7% (34/56) before neoadjuvant chemotherapy (P = 0.008). The expression of BCRP mRNA after neoadjuvant chemotherapy was 19.6%, significantly lower than 37.5% before neoadjuvant chemotherapy (P = 0.036). The positive rate of HER-2 mRNA expression was 41.1% before the chemotherapy, and reduced to 21.4% after the chemotherapy (P = 0.025). The effective rates of the single positive expression of Survivin mRNA or BCRP mRNA were both lower than that of negative expression (P < 0.05). The level of HER-2 mRNA expression alone was not significantly associated with the effective rate of chemotherapy (P = 0.144). When the expression of all Survivin mRNA, BCRP mRNA and HER-2 mRNA were negative, the effective rate of neoadjuvant chemotherapy was higher than that in patients with positive expression (P = 0.003). The level of Survivin mRNA expression was not significantly associated with BCRP mRNA and HER-2 mRNA (P > 0.05). The expression of Survivin in combination with BCRP and HER-2 is associated with clinical response to TE neoadjuvant chemotherapy in breast cancer, and can be used as predictive biomarkers for chemosensitivity of TE regimen neoadjuvant chemotherapy for breast cancer.