We used immunofluorescence (IF), immunohistochemistry (IHC) and immunoblotting (IB) to examine the subcellular localization of ITCH in the following cultured human normal and cancerous breast cell lines with differential tumorigenic and invasive potential: non-tumorigenic mammary epithelial cells (MCF10A); tumorigenic, but non-invasive BC cells (MCF-7); and invasive TNBC cells (MDA-MB-231). This evidence concerns the gene ITCH and breast cancer.