Metformin Exhibits an Attractive Antineoplastic Effect on Human Endometrial Cancer by Regulating the Hippo Signaling Pathway

Figure 4

The Hippo signaling pathway may be an antitumor target of metformin in endometrial carcinoma cells. The possible mechanism of the antitumor effect of metformin was explored in Ishikawa cells. (a and b) Protein expression was detected using western blotting, and the relative protein level of p-YAP1/YAP1 increased obviously in the metformin-treated group. (c and d) A dramatic decrease in the protein expression of LATS was observed in the treatment group. (e) The YAP1 mRNA level showed a consistent trend with the protein level. YAP1 knockout (YAP1-KO) Ishikawa cells were obtained using the CRISPR/Cas9 technique. (f–h) Both the mRNA and protein levels of YAP1 were examined in YAP1-KO Ishikawa cells. (i) The cell proliferation ability of YAP1-KO Ishikawa decreased significantly compared with that of the control groups. (j and k) The transwell invasion assay also indicated a decreased invasion ability in YAP1-KO Ishikawa cells. (l and m) Knockout of YAP1 in Ishikawa cells sharply increased the percentage of apoptotic cells. Each experiment was performed in triplicate and repeated at least three times independently. Data are presented as the mean ± SD. ; versus controls. Met, metformin; BC, blank control; NC, negative control; KO, knockout.

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