Objective To detect the expression of humar telomerase reverse transcriptase (hTERT) and telomerase activity in HeLa,MCF-7,SMMC7721 PC-3m and U2OS cell lines. Methods The techniques of immunochemistry and TRAP-ELISA were employed to detect the expression of hTERT and telomerase activity in different tumor cell lines.Results The positive rate of hTERT in HeLa cells(93.75%?3.10%)was significantly higher than that in U2OS cells(2.75%?0.96%),besides the other three cell lines showed an positive rates of hTERT in MCF-7(92.50%?2.65%),SMMC7721 (53.75%?2.22%)and PC-3m(23.50%?2.89%); Meanwhile,the telomerase activity of HeLa cells (94.58%?3.49%) was also much higher than that of U2OS(3.02%?0.43%),likewise the telomerase activities of the other three cell lines (MCF-7,SMMC7721,PC-3m) were 73.90%?4.50%,66.67%?3.35% and 50.62%?1.96%, respectively. Conclusion The expression of hTERT and telomerase activity show obvious differences among five tumor cell lines,suggesting that telomerase inhibitors cannot effect on all the tumor cell lines.

Objective:To investigate the effect of interleukin-1β (IL-1β) on epithelial-mesenchymal transition (EMT) and cytoskeleton rearrangement of renal tubular epithelial cells.Methods:Immortalized renal tubular epithelial cell line NRK52E was cultured in vitro with IL-1β (30 μg/L) for 3 days and 6 days,then the cell morphology was observed;The mRNA expressions of α-smooth muscle actin (α-SMA),cytoskeleton components β-actin and α-tubulin were semi-quantitative examined by RT-PCR.The protein expression of α-SMA and arrangements of β-actin and α-tubulin were assessed by immunofluorescent staining.Results:After induced by IL-1β for 3 days and 6 days in vitro,the mRNA and protein expression of α-SMA increased significantly compared with corresponding control cells (P<0.001),it prompted that NRK52E cells underwent EMT;At the same time,the cell morphology also changed,from a typical multilateral paving stone to fibroblast-like appearance,with multiple processes; Cytoskeletal protein β-actin mRNA expression was also slightly increased (P<0.05).The distributions and arrangements of β-actin protein were also changed,from cell membrane transferred to peri-nucleus and cytoplasm,moreover it formed fiber bundle-like structures.However,another cytoskeleton protein α-tubulin in IL-1β induced cells,neither it's mRNA expression nor it's distribution had significant differences compared with the control group.Conclusion:IL-1β can induce NRK52E cells undergoing EMT in vitro,cell morphology changes into fibroblast-like appearance with multiple processes,and also the cytoskeleton protein β-actin expression increases and rearrangement occurrs.However,there was no changes onα-tubulin.