TTC9 and female reproductive organ cancer: To delineate the targets that are involved in the MEK pathway activation and affect endocrine therapy sensitivity of gynecologic cancers, we selected the top five most significantly differentially expressed MEK_UP.V1_UP target genes in the ovarian, endometrial, and cervical tumors combined (NT5C2, CDC42BPB, MYOSA, PRKCH, PCDH1, TNFRSF21, SCAMP4, MPZL2, TTC9, MALL, INAVA, and EPHA2 [three genes overlapped in the three tumor types]) (Fig. 5c) for further investigation.