Effects Of Trichostatin A On The Proliferation And Apoptosis Of Human Colon Cancer HT-29Cell

Objective: To investigate the effect of histone deacetylase inhibitor on cellproliferation and apoptosis of human colon cancer cell line HT-29,also to explore itspossible mechanisms of anti-cancer effects.Methods:(1)Human colon cancer cell line HT-29wre treated with differentconcentrations(100,200,400,800,100nmol/L) of histone deacetylase inhibitor (TSA) fordifferent durations(24,48and72h). Cell proliferation was detected by methyl thiazolyltetrazolium(MTT) assay.(2)Cell cycle and apoptosis were assessed by flow cytometry(FCM)；（3）Reverse transcriplase polymerase chain reaction(RT-PCR) and Western Blotwere used to dectect the expression of p21,bax and bcl-2mRNA and protein.Results:(1) MTT assay demonstrated that the inhibitory effect of TSA on theproliferation of HT-29cell was found in dose-and-time dependent manner. There was greatstatistical signification between varies medicated group and control group (p<0.05), and therealso were great statistical signification between medicated group each other(p<0.05).(2)Flow cytometry showed that the HT-29cell cycle was induced by TSA at48hours,theapoptosis of the cell cycle increased, the ratio of G0/G1phase was increased and the ratioof S phase was decreased in dose-dependent manner (p<0.05).(3)RT-PCR assay showedthat the expression of p21,bax mRNA were up-regulated and bcl-2mRNA wasdown-regulated by TSA at48hours with drug concentration incread (p<0.05). WesternBlotshowed that the expression of p21,bax and protein were up-regulated and bcl-2protein was down-regulated with concentration increased (p<0.05).Conclusion: TSA could induce HT-29cell in vitro apoptosis and arrest cell cycle atthe phase of G0/G1in dose-and-time dependent maner within a certain range. May be themechanism works by upregulating the expressions of p21and bax mRNA and protein,downregulating the expression of bcl-2mRNA and protein.