Effects of small interfering RNA silencing of connexin 37 on subcutaneous tumor of gastric cancer in mice

Abstract

Objective To construct lentiviruses targeting mice connexin 37 (CX37) small interfeting RNA (siRNA) and modelling the gastric cancer with murine gastric cancer cell line.The lentiviruses were transfected into gastric cancer.Methods Lentiviruses carrying siRNA of CX37 were constructed,which knocked down mRNA and protein expression of CX37 significantly in vitro.Sixty mice with gastric cancer were randomly divided into CX37 siRNA group,mock-siRNA group and the control group,receiving injection of CX37 siRNA,mock-siRNA and normal saline respectively.After 6 weeks,the expression of CX37 mRNA and protein was detected by using semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting respectively.Apoptosis was examined by using TdT-mediated dUTP nick end labeling (TUNEL).Results Six weeks after lentivirus transfection,the results showed that the CX37 mRNA levels in CX37 siRNA group (42％) were significantly lower than in the mock group (63％)and control group (58 ％) (P ＜ 0.05).Western blotting revealed the expression of CX37 protein in CX37siRNA group was lower than in other three groups (0.21 ± 0.07 vs.0.65 ± 0.06 vs.0.54 ± 0.07).At the same time,the apoptotic index in CX37 siRNA group was higher than in mock-siRNA group and control group [(19.7±5.1)％ vs.(9.8±6.4)％ vs.(10.5±7.2)％,P＜0.05].Conclusion CX37 siRNA can significantly inhibit the growth of the gastric cancer cells. Key words: Gastric cancer; Connexin 37; Small interfering RNA