Effect of Short Hairpin RNA on Telomarase Activity and Cell Viability of Head and Neck Neoplasms

Objective: To investigate the effect of RNA interference by targeting human telomerase reverse transcriptase(hTERT) mRNA in the larynx cancer Hep-2 cell line and nasopharyngeal carcinoma NEC cell line.Methods: The primary structures of hTERT cDNA were found in GenBank.Then the structure analysis was done according to the strategy of RNA interference,by which the specific base sequences were determined to design shRNA(short hairpin RNA) plasmid.Plasmid shRNA1 involved in fluorescein gene were synthesized based on the specific base sequences.Control plasmid and shRNA2,a random sequence,were also constructed.Cells were treated daily with shRNA1,shRNA2 or only Lipofectamine.At 48 hours,the cell's telomerase activity was determined by the telomeric repeat amplification protocol(TRAP)-enzyme-linked immunosorbent assay(PCR-ELISA),and the morphology alteration of the cells was observed by HE stain.At 24,48 and 72 hours,cell viability after administration was determined respectively using the MTT assay.Results: It was observed that both Hep-2 cells and NEC cells treated with shRNA1 showed a decrease in telomerase activity compared to the other groups(all P0.05).The treatment with shRNA1 in the presence of a cationic liposome decreased cell viability of Hep-2 and NEC cells within three days(P0.05).Sparse cells in culture were also observed.While none of such effects were found in any other group.Conclusion: Short hairpin RNA by targerting human telomerase reverse transcriptase(hTERT) mRNA can inhibit laryngeal carcinoma and nasopharyngeal carcinoma cells'telomerase activity and induce cells to apoptosis.