miR-215 inhibits cell proliferation of SMMC7721 or Huh7 cells. 20 nmol/liter of miR-215, NC RNA, or PCAT-1 siRNAs was transfected into HCC cells, respectively. A, overexpression of miR-215 or two PCAT-1 siRNAs (siPCAT-1-1 and siPCAT-1-2) inhibits HCC cell growth. Cell number was counted at 24, 48, and 72 h after transfection. B, inhibition of miR-215 promotes HCC cell growth. Cell number was counted at 24, 48, and 72 h after transfection. C, in HCC cells with lncRNA PCAT-1 not significantly down-regulated (PCAT-1 mutant + miR-215), overexpression of miR-215 could not inhibit HCC cell proliferation. D, colony formation assays. At the 10th day after transfection, the colony number in each well was counted. All results of the mean of triplicate assays with mean ± S.D. are presented. *, p < 0.05; **, p < 0.01.