Effect of histone deacetylase inhibitor trichostatin A on radiosensitivity of human cervical cancer cell line HeLa under hypoxia condition / 肿瘤

ABSTRACT

Objective: To investigate the effects of histone deacetylase inhibitor trichostatin A (TSA) on radiosensitivity of human cervical cancer cell line HeLa under hypoxia condition. Methods: Under hypoxia condition, the HeLa cells were treated with different concentrations of TSA for 12, 24, 48 and 72 h, respectively. The survival rate of HeLa cells was detected by MTT assay. The half inhibitory concentration (IC50) and IC10 values for TSA were calculated. The radiosensitivity in HeLa cells treated with TSA (IC10) for 24 h under hypoxia condition was detected by colony formation assay. The expressions of hypoxia-inducible factor-1 alpha (HIF-1α) and vascular endothelial growth factor (VEGF) proteins were measured by immunocytochemistry. Results: The survival rate of HeLa cells induced by TSA and hypoxia was decreased in a concentration and time-dependent manner. The radiosensitivity of HeLa cells under hypoxia condition was increased by treatment with TSA (IC10) for 24 h (P <0.05). The expressions of HIF-1α and VEGF proteins were higher in HeLa cells exposed to hypoxia than that in HeLa cells exposed to normoxia. The expressions of HIF-1α and VEGF proteins in HeLa cells under hypoxia condition were decreased by treatment with TSA (IC10) for 24 h. Conclusion: TSA can significantly enhance the radiosentivity of HeLa cells under hypoxia condition. This effect may be related with the down-regulation of HIF-1α and VEGF protein expression. Copyright© 2011 by the Editorial Board of Tumor.