Concomitant reducing both KCNQ1OT1 and miR-15a in PC cells abolished the effects of KCNQ1OT1 silencing alone, suggesting that KCNQ1OT1 was essential for maintaining multiple malignant phenotypes of PC cells, and targeting miR-15a allowed for the pro-tumor activities of KCNQ1OT1. Here, KCNQ1OT1 is linked to pachyonychia congenita.