Expression of HOXA terminal transcript antisense RNA in hepatocellular carcinoma tissues and its effect on proliferation, invasion and migration of hepatocellular carcinoma HepG2 cells / 肿瘤研究与临床

ABSTRACT

Objective To investigate the expression of HOXA terminal transcript antisense RNA (HOTTIP) in hepatocellular carcinoma (HCC) tissues and to explore its effect on proliferation, invasion and migration in HepG2 cells. Methods A total of 60 cases with HCC tissues undergoing excision surgery and 60 cases of corresponding paracancerous tissues from January 2012 to June 2018 in Dandong First Hospital of Liaoning Province were collected. The expressions of HOTTIP in HCC tissues and paracancerous tissues were detected by using real-time quantitative polymerase chain reaction (RT-qPCR), and the relationship between the expression and clinicopathological features was analyzed. HepG2 cell line with high expression of HOTTIP constructed by cell transfer technique was treated as the experimental group, and the empty plasmid pcDNA3.1-NC was treated as the control group. The effect of HOTTIP on the proliferation of HepG2 cells was detected by using CCK-8 method, and the effect of HOTTIP on invasion and migration of HepG2 cells was detected by using Transwell assay. Results The expression of HOTTIP mRNA in HCC tissues was higher than that in paracancerous tissues, and there was no statistically significant difference (1.9±0.6 vs. 0.9±0.7, t=6.069, P<0.01). The whole HCC cases were divided into the high expression group (30 cases) and the low expression group (30 cases) according to the median value (1.92) of the expression of HOTTIP mRNA. The expression of HOTTIP was related with TNM stage, differentiation degree and lymph node metastasis (χ2 values were 10.800, 8.076, 5.711, all P<0.05), but not with age, gender, tumor diameter, number of tumors, hepatitis and alpha fetoprotein (AFP) levels (all P>0.05). The results of RT-qPCR showed that the expression of HOTTIP mRNA in HepG2 cells was increased after transfection of overexpressed HOTTIP and the differences was statistically significant compared with the control group (63±6 vs. 13±9, t=9.129, P<0.01). The results of CCK-8 method showed that the proliferation activity of cells was enhanced after the overexpression of HOTTIP in HepG2 cells (24 h, 36 h, 72 h at 490 nm absorbance was 1.497 ± 0.017 vs. 0.826 ±0.006, 2.002 ±0.025 vs. 1.211 ±0.020, 3.257 ±0.042 vs. 1.772 ±0.021), and the differences were statistically significant (t values were 5.321, 7.349, 8.793, all P < 0.01). In Transwell invasion assay, the number of cells transferred into the basement membrane in the experimental group was more than that in the control group (101 ±9 vs. 41 ±11), and the difference was statistically significant (t= 6.839, P< 0.01). In Transwell migration assay, the number of cells transferred into the basement membrane in the experimental group was more than that in the control group (112 ±9 vs. 53 ±11), and the difference was statistically significant (t=7.105, P<0.01). Conclusion The expression of HOTTIP in HCC tissues is up-regulated, and the overexpression of HOTTIP can promote the proliferation, invasion and migration of HCC cells.