JAG1 and ovarian cancer: By using a co‐IP assay, we also found that STAT3 could physically interact with Jagged1, and in addition we found that EMT key modulator and mesenchymal markers were down‐regulated and epithelial markers were up‐regulated by STAT3 inhibitors and Jagged1 inhibitors, which indicated Jagged1 could crosstalk with the STAT3 pathway and they cooperate to promote the occurrence of EMT in cisplatin‐resistant ovarian cancer cells.