DUSP6 and endometrial cancer: Our previous findings suggested that fibronectin, which is usually associated with the extracellular matrix, is an important factor in endometrial cancer SP cells and in invasion.15, 30 The protein level of fibronectin was downregulated by shRNA‐mediated DUSP6 knockdown in Hec1 and HHUA cells (Supporting Information Fig. S3a).