[Encounter of cancer cells with bone. Epithelial-mesenchymal transition in cancer].

Acquisition of invasive phenotypes of cancer cells is one of the key steps to promote metastasis. It has been reported that fibroblastic cells are involved in enhancement of proliferation and invasion of cancer cells. Thus, it is important to know the molecular mechanisms of EMT (epithelial-mesenchymal transition) for developing diagnosis and cancer therapy. Since TGF-βis a key mediator of EMT and frequently expressed in various tumors, it may regulate not only the EMT of cancer cells as they acquire metastatic properties, but also the EMT of normal epithelial cells that are adjacent to tumors. In this review, we will discuss the EMT induced by TGF-β.