Influence of trichostatin A on apoptosis of colon carcinoma cells and expression of HIF-1α under hypoxia in vitro / 第二军医大学学报

ABSTRACT

Objective: To observe the influence of trichostatin A (TSA) on the apoptosis of colonic cancer cell line HT-29 cells and expression of HIF-1α in HT-29 cells under hypoxia in vitro. Methods: HT-29 cells were treated with TSA(100, 200, 400, 600, 800 nmol/ L for 12, 24, 48, and 72 h. Cells in the control group were treated with the same volume of DMSO. MTT assay was used to investigate the survival of cells in each group. Annexin V and TUNEL were used to determine the apoptosis rate of HT-29 cells. RT-PCR and Western blotting were used to study the expression of HIF-1α mRNA and protein under hypoxia (37°C, 1% O2). Results: MTT assay demonstrated that cell viability decreased significantly in TSA-treated group compared to control group(P<0.05), and the inhibitory effect of TSA was in a dose- and time-dependent manner. Annexin V and TUNEL showed that TSA induced early apoptosis of HI-29 cells; the apoptosis rates in TSA treatment groups (200, 400, 600, and 800 nmol/L) were significantly higher than that of control group(P<0.05). TSA suppressed protein expression of HIF-1α under hypoxia in a dose-dependent manner but had no influence on mRNA expression of HIF-1α. Conclusion: TSA can induce apoptosis of HI-29 cells and inhibit their proliferation through suppressing expression of HIF-1α at protein level under hypoxia condition.