Ovarian cancer cell proliferation in vitro was evaluated using a CCK-8 assay. 
CCK-8
Western blotting was used to determine IGF1, IGF1R, AKT, p-IGF1, p-IGF1R, p-AKT, and MRP2 levels in cells treated with different concentrations of metformin and LY29400, an inhibitor of the insulin-like growth factor pathway. 
Western blotting
Changes in gene expression levels of MRP2, IGF1, IGF1R, and AKT were determined by fluorescence real-time quantitative PCR assay of CP70 cells treated with metformin. 
fluorescence real-time quantitative PCR assay