Abstract:Objective:To investigate changes of methylation status of ASC/TMS1 in QBC939 cell line of cholangiocarcinoma before and after combined DNA methylation and histone deacetylase inhibitors treatment, and the correlation of the apoptosis which is induced by caspase1, and methylation status of ASC/TMS1.
Methods :Apoptosis was detected by mixed dye including both AnnexinFITC and Propidium with flow cytometry technique, and changes of methylation and transcription of mRNA were explored by RTPCR and MSP techniques after the intervention of hydralazine and valproic acid either alone or combined for 24 hours and 48hours.
Results:The transcription of mRNA of TMS1/ASC gene and caspase1 reexpressed again after the combined intervention of hydralazine and valproic acid, which was higher than that of the cells treated with either hydralazine or valproate alone (P＜0.05). The demethylation effect of 48 h by combind intervention treatment was better than that of 24h (P＜0.05). The growth of the QBC939 cell line was inhibited, flow cytometry showed marked increase of apoptosis(49.88±0.044)%.
Conclusions:TMS1/ASCgene and caspase1 may reexpress after the synergistical intervention of hydralazine and valproic acid, and the effect is more obvious as the treatment time is extended. The apoptosis of QBC939 cell line is increased, which may be indued by caspase1 passway.