CCN5 and breast cancer: Having noted an adverse association between CCN5 and BC progression24 (Fig. 1A and B), we used MDA-MB-231and HCC-70 cell lines as in vitro TNBC model and side-population (SP)-model of MCF-7 cells as a mean to interrogate whether deficiency of CCN5-driven program in BC promotes cancer epithelial cells to mesenchymal stem cells and BC growth.