Effects on xenografts in nude mice of HeLa cells after silencing telomerase activity by RNA interference

Objective To observe the effects on the growth of HeLa cells and xenografts in nude mice after silencing human telomerase catalytic subunit(hTERT) gene and telomerase activity by RNA interference.Methods RNA interference and lipid formulation were utilized to screen the stable cell lines with telomerase activity inhibition.The telomerase activity of cell lines was evaluated by telomeric repeat amplification protocol(TRAP) ELISA(TRAP-ELISA).Cell proliferation was investigated by cell growth curve.Tumor growth in vivo was estimated by the volume and weight of xenografts in nude mice.Results Two stable cell lines with silenced hTERT gene and lowered telomerase activity(T1,T2) were chosen as experimental groups.One sable cell line with normal hTERT gene(N1),and normal HeLa cells were chosen as control groups.The cell proliferation ability of experimental groups was decreased compare with control groups(P0.05).There were tumor formation in both of experimental and control groups.After 20 days,all the nude mice were sacrificed.The weights of xenografts in nude mice were 0.057 7±0.034 9 g and 0.054 4±0.033 5 g in experimental groups(T1,T2),and 0.024 5±0.010 9 g and 0.027 2±0.0075 g in control groups respectively.There was significant difference between them(P0.05).Conclusion After silencing the hTERT gene of HeLa cells,the activity of telomerase can be inhibited,and the cell proliferation showed predominantly reduced,and also the weights of xenografts in nude mice diminished obviously.