Effect of hTERT Antisense on Cisplatin Sensitivity of Acute Lymphoblastic Leukemic Cells.

Abstract

AIM: To investigate the effect of human telomerase reverse transcriptase(hTERT) antisense phosphorothioate oligodeoxynucleotide(AS PS-ODN) on enhancing cisplatin sensitivity in acute lymphoblastic leukemic cells.METHODS: The expression levels of hTERT protein were detected by immunofluorescence using fluoresce isothiocyanate(FITC) lable. Cell surviving fraction was determined using the trypan blue dye exclusion assay. Apoptosis was detected by morphological observation and flow cytomertric cell cycle analysis.RESULTS: The expression of hTERT protein was inhibited after treated by hTERT AS PS-ODN. Treatment with cisplatin after 24h of exposure to AS PS-ODN had significantly reduced the number of viable ALL cells. However, there was no difference on ALL cells survival between sense oligodeoxynucleotide(S PS-ODN)/CDDP combination and CDDP treated cells alone. In morphological observation of apoptotic cells using Hoechst 33258 and PI double staining techniques, cells displayed classic apoptotic changes treated with CDDP or CDDP combined with hTERT AS PS-ODN or S PS-ODN at 48h. Apoptotic rates of cells added CDDP and AS PS-ODN were higher than that of cells added CDDP only(P<0.05). Apoptotic rates of cells added CDDP and S PS-ODN were similar with that of cells added CDDP only(P>0.05).CONCLUSION: hTERT AS-ODN inhibited the expression of hTERT protein and increased the CDDP induced apoptosis in primer acute lymphoblastic leukemic cells.