It has been reported that human bone marrow-derived mesenchymal cells may differentiate in vitro to fibroblast/myofibroblast-like cells under certain conditions, such as coculture with human colon carcinoma cells and TGF-β1, or prolonged exposure to conditioned medium from MDA-MB-231 breast cancer cells; these fibroblast/myofibroblast-like cells are able to promote tumour growth both in vitro and in vivo[36, 44–47]. The gene discussed is TGFB1; the disease is breast carcinoma.