Alterations of telomere length and hTERT expression in human gastric cancer cell line BGC-823 with silencing of hPOT1 by RNA interference

Background: Protection of telomere and regulation of telomere length are the two main functions of human protection of telomeres 1 (hPOT1) protein. Aims: To investigate the effect of hPOT1 on regulation of telomere length in human gastric cancer cells and its potential mechanism. Methods: Expression of hPOT1 in human gastric cancer cell line BGC-823 was inhibited by RNA interference (RNAi). Telomere length of BGC-823 cells was measured by real-time fluorescent quantitative polymerase chain reaction (PCR), and expression of human telomerase reverse transcriptase (hTERT) mRNA was determined by semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR). Results: Telomere length of BGC-823 cells in hPOT1 RNAi group was significantly shorter than that of parent BGC-823 cells and negative controls (P<0.05), whereas no significant difference was observed between parent cells and negative controls. T/S ratios (reflecting relative telomere length) in hPOT1 RNAi group, parent BGC-823 cells group and negative control group were 1.383±0.091, 2.758±0.647 and 3.043±0.548, respectively. Expression of hTERT mRNA was also down-regulated significantly in hPOT1 RNAi group. Conclusions: hPOT1 regulates the telomere length positively in human gastric cancer cells. Decrease of hTERT expression may be involved in the telomere shortening induced by hPOT1 down-regulation.