VALPROIC ACID INCREASES RADIATION SENSITIVITY OF ANAPLASTIC THYROID CARCINOMA CELLS

IRENE IVAÑEZ; GRACIELA A CREMASCHI; JUVENAL, GUILLERMO J.; CINTHIA ROSEMBLIT; PISAREV, MARIO A.; PERONA, MARINA; GRISSI C; HEBE DURAN

Virtual

Congreso; ICE 2021 Virtual:19th International Congress of Endocrinology, 4th Latin American Congress of Endocrinology and 13th Congress of the Argentine Federation of Endocrinology Societies.; 2021

ISE, FELAEN, FASEN

Introduction: Histone deacetylase (HDAC) inhibitors have emerged recently as promising anticancer agents. Theantitumor activity of HDAC inhibitors has been linked to their ability to induce gene expression through acetylation ofhistone 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, RTeither 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 ATCcell 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 afterirradiation. 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