ABSTRACT
Purpose To evaluate the expression of miR-21 in the tissues and cell lines of hepatocellular carcinoma,and to try to find its possible target genes.Methods The expression profile of miR-21 was detected in hepatocellular carcinoma tissues and cell lines.Mter miR-21 inhibitor was used,the alterations in the vitality and invasion of hepatocellular carcinoma cells were observed.The possible target gene of miR-21 was predicted by bioinformatics analysis.The influence of miR-21 inhibitors on the target gene activity was evaluated by dual luciferase reporting gene system.Results The expression level of miR-21 was significantly higher in hepatocellular carcinoma tissues than that in the adjacent ones (P ＜0.05).The expression level of miR-21 in hepatocellular carcinoma cells was significantly higher than that in the hepatic cells (P ＜0.01).After inhibiting miR-21,the viability and invasion ability of hepatocellular carcinoma cells were decreased (P ＜ 0.01).The expression level of programmed cell death 4 (PDCD4) in hepatocellular carcinoma tissues was significantly lower than that in the adjacent tissues (P ＜ 0.01).Its expression level in hepatocellular carcinoma cells was significantly lower than that in the hepatic cells (P ＜ 0.01).After interfering with PDCD4,the vitality and invasion ability of liver cancer cells were increased (P ＜ 0.05).Dual luciferase reporter gene assay indicated that by inhibiting miR-21,the expression level of PDCD4 was up-regulated (P ＜ 0.01).The vitality and invasion ability of liver cancer cells were reduced (P ＜ 0.001).Conclusion MiR-21 can regulate the growth and invasion of liver cancer cells through targeting PDCD4.
ABSTRACT
Objective To investigate the changes of serum miR-21 expression level in patients with HCC before and after transcatheter arterial chemoembolization (TACE) and to discuss its clinical significance. Methods Before and after TACE the levels of serum miR-21 in 42 patients with HCC and 42 healthy subjects were determined by reverse transcriptase quantitative PCR (RT-PCR), and the levels of serum AFP were also estimated by enzyme-linked immunosorbent assay (ELISA). The results were analyzed. Results The serum miR-21 level in patients with HCC was (12.9 ± 3.5) times of that in normal subjects(t=19.430 7, P < 0.01). One month after TACE, the serum miR-21 level became (7.2 ± 1.7) times of that of normal reference value, which was remarkably lower than that obtained before the treatment (t=9.493 7, P<0.01). The serum miR-21 level was closely correlated with the tumor size, the presence of tumor thrombus and HBV infection. One month after TACE the serum miR-21 levels in patient groups showing partial response, stable disease and progressive disease were (4.0 ± 0.3), (6.0 ± 1.5) and (8.6 ± 1.5) times, respectively, of that of normal reference value, and statistically significant difference existed between each other among the three groups (F=38.168, P=0.000). ROC-AUC value of MiR-21 in diagnosing HCC was 0.910 ± 0.041, which was significantly higher than that of AFP (0.860 ± 0.037, t=6.3042, P<0.01). The specificity of miR-21 in detecting HCC was 88.1%, which was remarkably higher than that of AFP (69%, χ2= 4.5253, P = 0.033).Conclusion After TACE the serum MiR-21 level in HCC patients is significantly decreased, which is very helpful in predicting the therapeutic efficacy of TACE. Therefore, MiR- 21 can be regarded as a potential molecular marker of HCC.