Antitumor Activity of Histone Deacetylase Inhibitor Trichostatin A in Osteosarcoma Cells

Background: Histone deacetylase (HDAC) inhibitors have been reported to induce cell growth arrest,apoptosis and differentiation of tumor cells. The present study aimed to examine the effects of trichostatin A(TSA), one such inhibitor, on the cell cycle, apoptosis and invasiveness of osteosarcoma cells.
Methods: MG-63 cells were treated with TSA at various concentrations. Then, cell growth and apoptosis were determinedby 3-(4, 5-dimethyl-2-thiazolyl)-2H-tetrazolium bromide (MTT) and TUNEL assays, respectively; cell cyclingwas assessed by flow cytometry; invasion assays were performed with the transwell Boyden Chamber system.
Results: MTT assays revealed that TSA significantly inhibited the growth of MG-63 cells in a concentrationand time dependent manner. TSA treated cells demonstrated morphological changes indicative of apoptosisand TUNEL assays revealed increased apoptosis of MG-63 cells after TSA treatment. Flow cytometry showedthat TSA arrested the cell cycle in G1/G2 phase and annexin V positive apoptotic cells increased markedly. Inaddition, the invasiveness of MG-63 cells was inhibited by TSA in a concentration dependent manner.
Conclusion:Our findings demonstrate that TSA inhibits the proliferation, induces apoptosis and inhibits invasiveness ofosteosarcoma cells in vitro. HDAC inhibitors may thus have promise to become new therapeutic agents againstosteosarcoma.