RNA interference remarkably suppresses bcl-2 gene expression in cancer cells in vitro and in vivo.
Bcl-2 is an anti-apoptotic protein. If the level of Bcl-2 protein can be reduced sufficiently in tumors using RNA interference (RNAi) to target the gene message, the apoptosis of tumor cells may be promoted. In this study, we synthesized 19 nucleotides (nts) small interference RNA (siRNA) constructs suppressing bcl-2 gene expression in human tumor cells (HeLaB2 and BGC-823 cell lines) in vitro. The bcl-2 gene expression levels were significantly reduced when these siRNA were transfected into experimental two tumor cells for 72 hours. The apoptosis process was also examined in the tumor cells. Here we synthesized siRNA from a DNA template under the control of the RNA polymerase III promoter in transfected tumor cells. Using this DNA vector-based approach, we found that the siRNA efficiently and specifically inhibited the synthesis of protein encoded by the bcl-2 gene in HeLaB2 and BGC-823 tumor cells. Tumor growth was inhibited by 66.5% with 2mg/kg pSilencer 3.1H1-bcl-2 in mouse liver tumor-bearing BALB/c mice. This approach may prove to be a valuable clinical technique for the analysis of specific gene functions and gene therapy of malignant tumors that utilize the bcl-2 gene via RNA interference.
Fu
Geng-Feng
GF
Medical School and State Key Loboratory of Pharmaceutical Biotechnology, Nanjing University, China.
Lin
Xue-Hong
XH
Han
Qing-Wang
QW
Fan
Yan-Rong
YR
Xu
Ye-Fen
YF
Guo
Dan
D
Xu
Gen-Xing
GX
Hou
Ya-Yi
YY
D000818:Animals; D017209:Apoptosis; D045744:Cell Line, Tumor; D015536:Down-Regulation; D015870:Gene Expression; D019254:Genes, bcl-2 / Q000235:genetics*; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000235:genetics; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009369:Neoplasms / Q000737:chemistry / Q000235:genetics / Q000628:therapy*; D010957:Plasmids / Q000235:genetics; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis / Q000037:antagonists & inhibitors* / Q000235:genetics; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D037941:Silencer Elements, Transcriptional / Q000235:genetics; D023041:Xenograft Model Antitumor Assays
D019253:Proto-Oncogene Proteins c-bcl-2; D034741:RNA, Small Interfering