Expression of long non-coding RNA hypoxia-inducible factor-1α antisense RNA-2 in hepatocellular carcinoma and its effect on proliferation and invasion

Objective To detect the expression of long non-coding RNA hypoxia-inducible factor-1α antisense RNA-2 (lncRNA-HIF1A-AS2) in hepatocellular carcinoma (HCC) and cell lines and its effect on proliferation and invasion of hepatoma cells. Methods Real-time fluorescent quantitative polymerase chain reaction (FQ-PCR) was used to detect the expression of HIF1A-AS2 in 49 HCC tissues and adjacent normal tissues, four HCC cell lines(Huh7, HepG2, SMMC-7721, Bel-7402) and one normal liver cell line L02, then analyze the correlation between HIF1A-AS2 expression and clinicopathological features; Two high-expression HIF1A-AS2 HCC cells were transfected into small interfering RNA (si-HIF1A-AS2) and negative control (si-NC); Cell counting kit 8 (CCK-8) assay and Colony-forming assay were conducted to evaluate the cell proliferation; Transwell assay was conducted to evaluate the cell invasion. Results The expression of HIF1A-AS2 in HCC tissues was higher than that in adjacent tissues (-12.060±0.657 vs. -12.450±0.683, P<0.01); The expression of HIF1A-AS2 was correlated with age, tumor size and tumor differentiation (χ2=4.573, 4.871, 8.353, P<0.05); The expression of HIF1A-AS2 in HCC cell line was also significantly higher than that in normal liver cell line, and the expression was highest in Huh7 and HepG2 (Huh7: 5.349±0.992, HepG2: 5.660±0.726, P<0.01); CCK8 assay and colony-forming assay showed that the cell proliferation ability after transfection of si-HIF1A-AS2 was significantly lower than that of the control group in Huh7 and HepG2 (Huh7: 0.668±0.067 vs. 0.558±0.055, 0.931±0.881 vs. 0.670±0.072, 1.769±0.079 vs. 1.036±0.074; HepG2: 1.063±0.0604 vs. 0.803±0.097, 1.767±0.091 vs. 1.083±0.080, P<0.01) (Huh7: 542.70±25.50 vs. 378.00±19.31, HepG2: 530.00±14.53 vs. 217.30±18.15, P<0.01); Transwell assay showed that the number of cell invasion was significantly lower after transfection of si-HIF1A-AS2 [Huh7: (116.300±6.506) cells vs. (520.000±9.539) cells, HepG2: (88.330±5.686) cells vs. (55.000±5.245) cells, P<0.01]. Conclusion HIF1A-AS2 is highly expressed in HCC and cell lines, and down-regulation of HIF1A-AS2 expression can inhibit the proliferation and invasion ability of HCC cells. Key words: Hepatocellular carcinoma; Long non-coding RNA hypoxia-inducible factor-1α antisense RNA-2; Proliferation; Invasion