Our results suggest a genuine role of the MEK5-ERK5 pathway in mediating EC proliferation, at least in epithelial EC cells that express EGFR, as it has been reported for other carcinoma cancers, such as hepatocellular carcinoma [36], prostate adenocarcinoma [37] or non-small cell lung cancer [20]. Here, EGFR is linked to non-small cell lung carcinoma.