The important role of Gli-1 in hypoxia-induced epithelial-mesenchymal transition of breast cancer cell line MDA-MB-231

Objective: To investigate the important role of Gli-1 in hypoxia-induced epithelial-mesenchymal transition of breast cancer cell line MDA-MB-231.

Methods: For the present study, breast cancer cell line MDA-MB-231 was cultured under normoxic or hypoxic condition. Then, the shRNA of Gli-1 was stably transfected into MDA-MB-231 cells. Invasion of MDA-MB-231 was detected by the Transwell assay. The expressions of HIF-1α, Gli-1, E-Cadherin and vimentin proteins were determined by Western blot.

Results: Hypoxia significantly induced the invasion of MDA-MB-231 cells, upregulated the expressions of HIF-1α, Gli-1 and vimentin proteins, and downregulated the expression of E-Cadherin protein. Furthermore, knocking down Gli-1 obviously abrogated hypoxia-induced epithelial-mesenchymal transition and enhanced invasion of MDA-MB-231 cells.

Conclusion: Hypoxia induces epithelial-mesenchymal transition and enhances invasion of breast carcinoma cells via strengthening Gli-1 expression and activation of Hedgehog pathway.