Expression and significance of Shh and Gli-1 in drug-resistant cell strain of human breast cancer MCF-7

LIU Ruijuan; ZANG Chuanxin; SUN Yue; HAN Nana; SUN Changgang

Abstract：Objective To investigate the expression of Shh,Gli-1 in human breast cancer resistant cell line and discuss the relationship between Hedgehog signaling pathway and drug resistance of breast cancer. Methods Drug-resistant strains of human breast cancer MCF-7 was established by high concentration intermittent induction. Paclitaxel( PTX) to half maximal inhibitory concen-tration( IC50 ) on MCF-7 and MCF-7/PTX cells was determined by MTT. QPCR was used to detect the mRNA expression of Shh, Gli-1 in MCF-7 and MCF-7/PTX cells. Protein expression of Shh, Gli-1 in MCF-7 and MCF-7/PTX cells was detected by Western blotting. Results IC50 of PTX for MCF-7 cells was ( 0. 10+0. 02) mg/L, and for MCF-7/PTX cell was ( 5. 30+0. 01) mg/L. The drug resistance index was 53. 0. The expression of Shh mRNA in MCF-7 and MCF-7/PTX cells was 0. 78 ± 0. 12 and 1. 45 ± 0. 56(P<0. 01), and the expression levels of Gli-1 mRNA was 1. 86±0. 02 and 3. 56±0. 26(P<0. 01). The expression level of Shh protein in MCF-7 and MCF-7/PTX cells was 0. 58 ±0. 06 and 1. 03 ± 0. 22(P<0. 01). Gli-1 protein expression in MCF-7 and MCF-7/PTX cells was 1. 17±0. 12 and 2. 78±0. 09(P<0. 01). Conclusion Shh, Gli-1 are highly expressed in MCF-7/PTX cells, indicating that chem-otherapy may guide drug resistance of breast cancer by up-regulating the protein and gene of hedgehog signaling pathway. The target to hedgehog signaling pathway may be a new direction to overcome drug resistance.