Hypoxia-mimetic by CoCl2 increases SLC7A5 expression in breast cancer cells in vitro
Leonora Canhasi, Elisabet Tina, Anna Göthlin Eremo
Abstract
Abstract Objective Increased expression of the amino acid transporter solute Carrier Family 7 Member 5 (SLC7A5) has been observed in neoplastic cells during hypoxic conditions in vitro, indicating an adaptation for cell survival. To further explore this, we evaluated hypoxia-mimetic by CoCl2 as a model for hypoxia in breast cancer cell lines and the effect on SLC257A5 expression. Four different breast cancer cell lines (MCF7, T-47D, BT-474 and ZR-75-1) were exposed to 100 µM CoCl 2 for 48 h. Subsequently, cell viability, gene- and protein expression analyses were performed. Results The gene expression of VEGF, a marker of hypoxia, was significantly elevated in all four cell lines compared to the control (p < 0.0001), indicating that CoCl 2 exposure generates a hypoxic response. Moreover, CoCl 2 exposure significantly upregulated SLC7A5 gene expression in T-47D (p < 0.001), BT-474 (p < 0.0001) and ZR-75-1 (p < 0.0001) cells, as compared to vehicle control. Immunofluorescence staining showed increased SLC7A5 protein expression in MCF7, T-47D and BT-474 cells compared to vehicle control. This report suggests that hypoxia-mimetic by CoCl 2 can be used as a simple model for inducing hypoxia in breast cancer cell lines and in fact influence SLC7A5 gene and protein expression in vitro.