Regulatory effect of small nuclear ribonucleoprotein-associated protein B on proliferation and metastasis of liver cancer cells / 中华肝脏病杂志

Objective: To study the expression and effect of small nuclear ribonucleoprotein-associated protein B (SNRPB) on proliferation and metastasis of liver cancer tissues and cells. Methods: The bioinformatics database starBase v3.0 and GEPIA were used to analyze the expression of SNRPB in liver cancer tissue and normal liver tissue, as well as the survival and prognosis of liver cancer patients. The expression of SNRPB mRNA and protein in liver cancer cell lines were analyzed by qRT-PCR and Western blot. RNA interference technique (siRNA) was used to determine SNRPB protein expression down-regulation. The proliferation effect on hepatocellular carcinoma cells was observed by MTT assay. Transwell invasion and migration assay was used to detect the changes in the metastatic ability of liver cancer cells after SNRPB down-regulation. Western blot was used to detect the changes of epithelial mesenchymal transition (EMT) markers in liver cancer cells after down-regulation of SNRPB expression. Data were compared between two groups and multiple groups using t-test and analysis of variance. Results: The expression of SNRPB was significantly higher in liver cancer tissue than normal liver tissue, and its expression level was correlated with the prognosis of liver cancer patients. Compared with the immortalized hepatocyte LO(2), the expression of SNRPB was significantly increased in the liver cancer cells (P < 0.01). siRNA-SNRPB had significantly inhibited the expression of SNRPB mRNA and protein in liver cancer cells. MTT results showed that the absorbance value was lower in SNRPB knockdown group than negative control group, and the difference at 96 h after transfection was most significant (P < 0.01). Transwell assay results showed that compared with the negative control group, the SNRPB knockdown group (MHCC-97H: 121.27 ± 8.12 vs. 46.38 ± 7.54; Huh7: 126.50 ± 6.98 vs. 41.10 ± 8.01) invasion and migration (MHCC-97H: 125.20 ± 4.77 vs. 43.18 ± 7.32; Huh7: 132.22 ± 8.21 vs. 38.00 ± 6.78) ability was significantly reduced (P < 0.01) in liver cancer cells. Western blot showed that the expression level of epithelial phenotype marker E-cadherin was decreased after down-regulation of SNRPB, while the expression levels of mesenchymal phenotype markers N-cadherin and vimentin was increased, suggesting that down-regulation of SNRPB inhibited EMT in liver cancer cells. Conclusion: SNRPB expression is significantly increased in liver cancer tissues and cells, and it is involved in regulating the proliferation, metastasis and EMT of liver cancer cells.

MiR-106a induces peritoneal metastasis through acting on TIMP2 in human gastric cancer cell BGC-823 / 西安交通大学学报(医学版)

Objective To investigate the induction of microRNA (microRNA-106a,miR-106a)on the peritoneal metastasis of human gastric cancer cell BGC-823 by regulating matrix metalloproteinase inhibitor 2 (tissue inhibitor of metalloproteinases 2,TIMP2).Methods Human gastric cancer cell line BGC-823 was cultured to the logarithmic growth phase. The cells were divided into three groups: BGC-823, BGC-823/anti-miR-106a (antagomir)and BGC-823/negative control.Real-time PCR was used to identify the effect of antagomir.Transwell assay was used to detect the cell migratory and invasive abilities of these three groups in vitro .With small incision, the cells were injected into the abdominal cavity of nude mice to prepare a xenograft model.The animals were divided into two groups:miR-antagomir and miR-NC.The tumor growth in the nude mice was generally observed and estimated.Immunohistochemistry and Western blot methods were used to detect the expression of metastasis-associated protein TIMP2 on the several abdominal organs.Results The expression level of miR-106a was down- regulated in BGC-823/anti-miR-106a group,with the fold change of 0.05±0.01,which was significantly different from that in NC group (t=-18.001,P＜0.001).In vitro exogenously silencing of miR-106a gene,the numbers of invasive and migratory cells in BGC-823/anti-miR-106a group were both significantly lower than those in BGC-823 and BGC-823/negative control groups (P＜0.001).In vivo xenograft model showed that the down-regulation of miR-106a weakened the peritoneal metastasis ability of BGC-823 cells in nude mice abdominal cavity,which was reflected by the decrease of tumor number and tumor size.With the inhibition of miR-106a,the expression of TIMP2 in miR-antagomir group was significantly higher than that in miR-NC group (P＜0.05).Conclusion BGC-823 cell has the tumorigenicity in nude mice.Silencing of miR-106a inhibits gastric cancer cell metastasis, which suggests that it has the oncogenic function.MiR-106a may induce the strengthened peritoneal metastasis ability of BGC-823 cell through acting on TIMP2.

Effect of Tanshinone II A on expression of EGF and EGFR in hepatocellular carcinoma cell line SMMC-7721 / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To observe the effect of Tanshinone II A on the expression of epidermal growth facter (EGF) and epidermal growth facter recepter (EGFR) in human hepatocellular carcinoma cell line SMMC-7721.</p><p><b>METHODS</b>The human hepatocellular carcinoma SMMC-7721 cells cultured in vitro was treated with different concentrations of Tanshinone II A. The proliferation of the cells was measured by MTT assay, and the apoptosis of the cells was investigated by flow cytometry and cytochemical staining with Hoechst 33342. The expression of EGF and EGFR was detected by immunocytochemistry method. The levels of EGF in medium were measured by radioimmunoassay.</p><p><b>RESULT</b>Tanshinone II A inhibited the growth of SMMC-7721 cells remarkably in a dose-dependent manner. The inhibitory rate reached the peak (72.5%) after 0.5 microg/ml Tanshinone II A was used for 48 h, which was significantly higher than that in the controls (P<0.05). FCM analysis showed that when SMMC-7721 cells were treated with 0.5 microg/ml Tanshinone II A, the apoptosis rates for 24 h, 48 h and 72 h were (4.06+/-0.27)%, (7.58+/-0.56)% and (5.23+/-0.13)%, respectively which were markedly higher than those in the controls (all P<0.01). SMMC-7721 cell apoptosis with cell shrinkage, nuclear chromatin concentration and fragmentation as well as the formation of apoptotic bodies were observed by cytochemical staining when treated with Tanshinone II A. The immunocytochemistry showed that the expressions of EGF and EGFR were down regulated while the concentration of Tanshinone II A was increasing. The high expression rates for EGF and EGFR were 10%, 20%, respectively, and the gray scale was 181.52+/-1.63, 179.37+/-1.59, which were markedly higher than those in the controls (all P<0.05). The levels of EGF in medium measured by radioimmunoassay were decreased significantly after Tanshinone II A treatment.</p><p><b>CONCLUSION</b>Tanshinone II A can inhibit cell proliferation and induce apoptosis in hepatocellular carcinoma cell line SMMC-7721, which may be related to the down-regulation of EGF and EGFR protein expression.</p>