Title: RNA interference by expression of short hairpin RNAs suppresses bcl-xL gene expression in nasopharyngeal carcinoma cells1
Abstract: To evaluate a new plasmid mediated RNA interference (RNAi) system and investigate whether knock-down of bcl-xL by short hairpin RNA (shRNA) can induce apoptosis of human nasopharyngeal carcinoma (NPC) cell line CNE-2Z in vitro. The plasmid containing mU6 promoter was subcloned to yield the pmU6 plasmid, recombinant plasmid expressing shRNA targeting bcl-xL gene was designed and constructed, and were co-transfected cells with green fluorescence protein expressing plasmid. Flow cytometry was used to evaluate transfection efficiency, and RT-PCR and Western blot were applied to analyze bcl-xL mRNA and protein levels, respectively. The shRNA expressed by the recombinant plasmid efficiently suppressed bcl-xL gene expression and induced apoptosis of NPC cells in vitro. The recombinant plasmid can sufficiently mediate RNAi in CNE-2Z cells, and knock-down of the bcl-xL expression by shRNA significantly induced apoptosis in CNE-2Z cells. The results suggest this new system, mediated RNAi can be used as a tool for the study of gene function and gene therapy.