Enhancement of cisplatin -induced apoptosis in HL-60 cells by human telomerase reverse transcriptase antisense oligodeoxynucleotide

AIM: To explore the effects of the combined use of human telomerase reverse transcriptase (hTERT) gene antisense oligodeoxynucleotide (ASODN) and cisplatin on apoptosis of HL-60 cells. METHODS: PCR-ELISA was used to determine telomerase activity in HL-60 cells untreated or treated with ASODN, the expression levels of hTERT protein were assayed by immunofluorescence using fluoresce isothiocyanate (FITC) label. Apoptosis was detected by DNA electrophoresis and flow cytomertric cell cycle analysis. RESULTS: The expression levels of hTERT protein and telomerase activity in HL-60 cells treated with ASODN were shown to decrease with time, the DNA fragments were obviously found and the percentage of apoptosis cells was significantly enhanced in HL-60 cells with the combined use of hTERT ASODN and cisplatin compared with the combined use of hTERT sense oligodeoxynucleotide and cisplatin or cisplatin alone, respectively. CONCLUSION: Inhibition of telomerase activity by hTERT ASODN increases the cisplatin-induced apoptosis of HL-60 cells.