Objective To construct the eukaryotic expression vector of human telomerase RNA component ( hTR) and study its biological function tentatively .Methods hTR Gene was obtained by PCR from cDNA template , which was reverse transcribed from 293T mRNA and cloned into pCDNA3.0 vector.The recombinant plasmid and empty vector were trans-fected into 293T cells, and hTR expression was identified by qRT-PCR.HepG2 cells that stably transfected with pCDNA3.0-hTR were constructed and identified by qRT-PCR.These cells were used to assess the interaction of hTR with human telomerase revese transcriptase ( hTERT ) and dyskerin .Telomerase activity was also detected in HepG 2 cells transfected with pCDNA3.0-hTR.Results pCDNA3.0-hTR eukaryotic expression vector was successfully constructed by double digestion identification .The inserted fragment was confirmed by sequencing .The expression of hTR in human 293T cells and HepG2 pCDNA3.0-hTR stable cell line was identified.In addition, qRT-PCR and Western blotting results showed that hTR could interact with hTERT and dyskerin , while hTR overexpression could not regulate the telomerase activity in HepG2 cells.Conclusion The eukaryotic expression vector of pCDNA 3.0-hTR is successfully constructed and expressed.This study will contribute to the further study of cancer therapy targeting hTR .

Objective To construct PES1 shRNA stable expression cell lines in tongue squamous cell carcinoma ( TSCC) cells and to study the effect of knockdown of PES 1 on the growth of TSCC cells .Methods Recombinant lentivirus carrying PES1 shRNA was packaged and obtained in 293T cells.TSCC cells (Tca8113, SCC6 and SCC15) were infected with the lentivirus and selected for stable cells .PES1 expression was identified by Western blot .The effect of inhibition of PES1 on the growth and cell cycle of TSCC cells was detected by growth curve and flow cytometry .Results TSCC cells stably expressing PES1 shRNA were constructed.Knockdown of PES1 inhibited cell proliferation and induced cell cycle ar-rest at G0/G1 phase.Knockdown of PES1 inhibited expression of cyclin D1 in TSCC cells.Conclusion Inhibition of PES1 results in reduced cell proliferation , cell cycle arrest at G 0/G1 phase and reduction of cyclin D 1 expression in TSCC cells . PES1 may be a target for TSCC gene therapy .