Our 4T1 panel of breast cancer cells are well-tractable syngeneic model consisting of cells stably expressing control shRNA (4T1 shCTL) and BST-2-targetting shRNA (4T1 shBST-2), as well as 4T1 shBST-2 cells with constitutive expression of human BST-2 (OE BST-2D)7,28, that is resistant to shRNA directed toward the murine isoform. The gene discussed is BST2; the disease is breast cancer.