AREG and ovarian cancer: Intercepting EGFR-ERK signaling pathway through blocking EGFR has been widely used in treating colon, breast, lung and head and neck cancers in recent years,61, 84 yet the efficacy of blocking EGFR in treating ovarian cancer has not been significant.85 Since AREG has been suggested as a promising target in cancer treatment, suppressing AREG to target ovarian cancer stem cells via inhibiting EGFR-ERK signaling pathway could be a reasonable option.15, 16, 61, 83 Our results also suggest that targeting AREG by miR-34c-5p might be an alternative strategy to inhibit ovarian cancer stem cells.