Human telomerase reverse transcriptase-targeted short hairpin RNA-expressing vector suppresses breast cancer cell proliferation through inhibition of telomerase activity in vitro

Objective To observe the effects of human telomerase reverse transcriptase (hTERT)directed short hairpin RNA (shRNA)-expressing plasmid on telomerase activity and proliferation in breast cancer cell T47D.Methods hTERT-directed shRNA-expressing plasmid was transfected into T47D cells with liposome.Reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting were used to detect the expression of hTERT mRNA and protein.The telomerase activity was examined by using tartrate resistant acid phosphatase (TRAP)-enzyme linked immunosorbent assay (ELISA).MTT assay was used to draw cell growth line,and cell cycles were detected by using flow cytometry.Results Compared with T47D control group,the expression levels of hTERT mRNA and protein,and telomerase activity in small interfering RNA (siRNA)1 group and siRNA2-N group were decreased with no statistical significance (P＞0.01),while those in siRNA2 group were decreased by 57.1％,57.0％ and 57.0％ (P＜0.01),those in siRNA3 group were decreased by 53.7％,53.4％ and 56.5％ (P ＜0.01),and those in siRNA4 group were decreased by 70.0％,70.3％ and 81.9％ (P ＜0.01),respectively.The cell growth rate and cell cycles in siRNA1 and siRNA2-N groups changed with no statistical significance (P ＞ 0.05),while the cell growth rate in siRNA2,siRNA3 and siRNA4 group was decreased at the first 24 h (P ＜ 0.01),and the cell cycles changed significantly (P ＜ 0.01).Conclusion The hTERT-targeted shRNA-expressing vector can inhibit the proliferation of cancer cells. Key words: Breast carcinoma;  Telomerase;  RNA interference;  Proliferation