TGFB1 and ovarian carcinoma: Furthermore, the expression of TGF-β1 in advanced stage and poorly-differentiated epithelial ovarian cancer was significantly lower than that in early stage and well-differentiated tumors, indicating that the autocrine loop of TGF-β1 may be involved in the process of apoptosis in tumor cells (4), which was suppressed in the advanced and poorly-differentiated tumors.