MAM protein was detected in the membrane fraction of the breast cancer cells at first by Western blot assay; Secondly, the binding of the FITC-labeled anti-MAM antibody was found on the breast cancer cells as visualized by fluorescent microscope; and the third, two MAM immunohistochemical stain patterns were identified in breast tissues (the membrane and luminary stain patterns) that are linked with the membrane-associated MAM proteins. This evidence concerns the gene SGCG and breast cancer.