Effect of small interference RNA silenced S100A4 protein in human gastric carcinoma cells on proliferation, apoptosis and chemotherapy sensitivity in vitro / 国际外科学杂志

Objective To study the application of small interfering RNA silencing S100A4 protein in human gastric cancer cell BGC-823 proliferation,apoptosis and the effect of chemotherapy sensitivity.Methods Human gastric carcinoma cell line BGC-823 transfection siRNA,RT-PCR detected the changes of mRNA after transfection.Groups divided into interference group,negative control group and normal control group.MTT test determined different concentrations of oxaliplatin in gastric cancer cells and calculated IC50,then draw cell growth curve,TUNEL method to detect apoptosis,RT-PCR tested each cell mRNA changed,Western blot detected the change of the S100A4 protein.All data analysis by SPSS17.0,t test applied,RT-PCR and Western blot results analysis by SPSS17.0,comparing multiple samples by using single factor analysis of variance and LSD test.P ＜ 0.05 was statistically significant.Results RT-PCR results showed that BGC-823 cell transfection,S100A4mRNA expression quantity respectively after 48 hours:(0.674+0.011),(0.652+0.021),(0.345 + 0.040),the interference group and normal control group were statistically significant (P =0.012,P ＜ 0.05) and the negative control group with interference group differences were statistically significant (P =0.000,P ＜ 0.05),and normal control group was no statistically significant difference with the negative control group (P =0.380,P ＞ 0.380);Western blot results showed BGC-823 cell transfection S100A4 expression significantly lowered respectively after 48 hours,there were (0.654 + 0.025),(0.642 + 0.014),(0.317 ± 0.061),the interference group and normal control group was statistically significant (P =0.01,P ＜ 0.05),between negative control group and interference group were statistically significant (P =0.000,P ＜ 0.05),normal control group and the negative control group had no significant difference (P =0.341,P ＞ 0.341).After S100A4-siRNA transfection,gastric carcinoma BGC-823 cell proliferation decreased,TUNEL method showed obviously increase apoptosis,MTY showed that IC5o of oxaliplatin was 56.31 μmol/L,after transfection,IC50 was 0.654 μmol/L.Conclusions This study showed that the siRNA silence S100A4 protein inhibit gastric cancer cell proliferation,induced apoptosis and improved chemotherapy sensitivity of oxaliplatin.S100A4 might be prompt targets for the treatment of gastric carcinoma.

In vitro and in vivo inhibition of rabies virus replication by RNA interference

Rabies is a zoonotic disease that affects all mammals and leads to more than 55,000 human deaths every year, caused by rabies virus (RABV) (Mononegavirales: Rhabdoviridae: Lyssavirus). Currently, human rabies treatment is based on the Milwaukee Protocol which consists on the induction of coma and massive antiviral therapy. The aim of this study was to assess the decrease in the titer of rabies virus both in vitro and in vivo using short-interfering RNAs. To this end, three siRNAs were used with antisense strands complementary to rabies virus nucleoprotein (N) mRNA. BHK-21 cells monolayers were infected with 1000 to 0.1 TCID50 of PV and after 2 hours the cells were transfected with each of tree RNAs in separate using Lipofectamine-2000. All three siRNAs reduced the titer of PV strain in a least 0.72 logTCID50/mL and no cytotoxic effect was observed in the monolayers treated with Lipofectamine-2000. Swiss albino mice infected with 10.000 to 1 LD of PV strain by the intracerebral route were also transfected after two hours of infection with a pool 3 siRNAs with Lipofectamine-2000 by the intracerebral route, resulting in a survival rate of 30% in mice inoculated with 100 LD50, while the same dose led to 100% mortality in untreated animals. Lipofectamine-2000 showed no toxic effect in control mice. These results suggest that intracerebral administration of siRNAs might be an effective antiviral strategy for rabies.

D-siRNAs suppresse expression of COX-2 in A549 cells / 基础医学与临床

Objective To cleave double-stranded RNA(dsRNA) into small interference RNAs(siRNAs) that can target multiple sites within an mRNA.Methods A549 cells were isolated to incubate with 5 g/L IL-1? for different times to detect the time-dependent expression of COX-2.To generate the long dsRNA,the COX-2 gene(728 bp) was amplified by PCR with a specific forward primer that contained a T7 promoter and a specific reverse primer that contained an SP6 promoter.Then,sense strand RNAs were generated by T7 RNA polymerase and antisense strands RNAs were generated by SP6 RNA polymerase.These single strands RNAs were annealed by the standard method.We mixed dsRNA with Dicer in reaction buffer.We recovered siRNAs using RNA Purification Column.Transfections with diced siRNAs were performed using the TransMessenger Transfection Reagent in accordance with the manufacturer's instructions.COX-2 mRNA and protein were determined by RT-PCR and Western blot respectively.PGE2 was measured by ELISA.Results IL-1? induced COX-2 protein expression in A549 cells.We recovered siRNAS that have been generated in vitro by Dicer.D-siRNAs significantly suppress the expression of COX-2 in human pulmonary epithelial.Conclusion D-siRNAs significantly suppress the expression of COX-2 in human pulmonary epithelial.