BSG and breast cancer: Breast cancer cell lines, including MCF7, MDA-MB-453, MDA-MB-231, and HCC38, were harvested and stained with mouse mAbs against CD147, CD146, CD73, and MHC class I. A FITC-conjugated F(ab′)2 goat antimouse IgG + IgM (H + L) secondary antibody was used for detection.