VALPROIC ACID INCREASES RADIATION SENSITIVITY OF ANAPLASTIC THYROID CARCINOMA CELLS

PERONA M ; IBAÑEZ I; ROSEMBLIT C; GRISSI C; CREMASCHI GA; PISAREV M; DURÁN H; JUVENAL GJ

Congreso; XIX Congreso Internacional de Endocrinología (ICE 2021); 2021

FASEN

Introduction: Histone deacetylase (HDAC) inhibitors have emerged recently as promising anticancer agents. The antitumor activity of HDAC inhibitors has been linked to their ability to induce gene expression through acetylation of histone and nonhistone proteins. Anaplastic thyroid cancer (ATC) is a rare and aggressive malignancy. Radiotherapy (RT) is one of the main modalities of treatment for ATC. In most patients, surgical resection is not possible. Therefore, RT either as altered fractionation or in combination with chemotherapy has an important role in achieving local control. Objectives: The objective was to study the effect of valproic acid in the radiation response at different doses in an ATC cell line.Methods: Cells (8505c) were incubated with 1 mM VA and irradiated with gamma rays at different doses (2 and 5 Gy). Radiation response was analyzed by clonogenic assay. Cell cycle and cell death were measured 24 and 48 h after irradiation. DNA damage and Ku80 expression were evaluated 30 min and 24 h after irradiation. MicroRNA (miR) expression was analyzed by microarray analyses at 2 Gy. Results: A reduction of survival fraction at 2 Gy was observed in the treated cells (p