TGFB1 and ovarian cancer: This mesenchymal change in MCs may have been caused by the release of a soluble growth factor from cancer cells as specific studies have already reported that a variety of factors collected from the conditioned media used to culture OvCa cells induced mesenchymal changes in MCs.23 Notably, TGF‐β1 has been recognized as one of the most common mesenchymal inducers of MCs.16, 19, 30 An average of 4.62 ng/ml (range: 0.38–22.34 ng/ml) of TGF‐β1 was detected in the ascites of patients with malignant ovarian tumors (Fig. 1c).