Effects of telomerase RNA-targeting antisense oligonucleotides PS-ASODN on proliferation, apoptosis and telomerase activity of the gastrointestinal stromal tumor cell line GIST867 cultured in vitro

Abstract

Objective To explore effects of the telomerase RNA-targeting antisense oligonucleotides PS-ASODN on proliferation,apoptosis and telomerase activity of the gastrointestinal stromal tumor cell line GIST867 cultured in vitro.Methods GIST867 cells in exponential phase were divided into following groups:control group,1 μmol/L imatinib group,and 1.25,2.50,5.00,10.00 and 20.00 μmol/L PSASODN groups.The anti-proliferation effect on GIST867 cells was determined by methyl thiazol tetrazolium (MTT) assay. The activity of telomerase was tested by using enzyme linked immunosorbent assay (ELISA).Apoptosis was examined by using flow cytometry.Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the expression of B lymphocytes/leukemia-2 (bcl-2) mRNA.Results MTT assay showed PS-ASODN could apparently inhibit the growth of GIST867 cells in a dose-dependent manner.The group of 5.00 μmol/L concentration showed more effectiveness than control group. PSASODN could apparently inhibit the telomerase activity in a time-dependent manner.Flow cytometry revealed that the apoptosis rate of the cells treated by PS-ASODN was ( 16.16 ± 1.35 ) ％,significantly higher than that in the control group and the imatinib group.Treatment with PS-ASODN significantly reduced the bcl-2 mRNA expression in the GIST867 cells.Conclusion PS-ASODN can repress the cell proliferation and induce the apoptosis of the GIST867 cells,which may be mediated by inhibition of the telomerase activity and down-regulation of the expression of bcl-2. Key words: Gastrointestinal stromal tumor; Antisense oligonucleotides; Proliferation; Telomerase