EFFECT OF VALPROIC ACID ON INCREASING RADIOSENSITIVITY IN ANAPLASTIC THYROID CANCER CELLS

PERONA, MARINA; IBAÑEZ, IRENE L.; ROSEMBLIT, C; GRISSI, CECILIA; CREMASCHI, G; PISAREV, M; DURÁN, HEBE; JUVENAL, GUILLERMO

Mar del Plata

Congreso; LXIV Reunión Conjunta de la Sociedad Argentina de Investigación Clínica (SAIC), LI Reunión Anual de la SAFE, XXI Reunión Anual de la SAB)y XXXI Reunión Anual de la SAP 2019; 2019

SAIC. SAFE. SAB. SAP Participan AACYTAL. NANOMED-AR. HCS

Introduction: Histone deacetylase inhibitors (HDACi) have emerged recently as promising anticancer agents targeting histone and nonhistone proteins. Many studies show as well that HDACi are effective radiosensitizers in various types of malignancies. Anaplastic thyroid cancer (ATC) is a rare and aggressive malignancy. Radiotherapy (RT) is one of the main modalities of treatment for ATC. RT either as altered fractionation or in combination with chemotherapy has an important role in achieving local control. Objectives: Our purpose was to study the combined effect of the HDACi, valproic acid (VA), and ionizing radiation in an anaplastic thyroid cancer cell line (8505c). Methods: Cell viability was evaluated by MTT assay. Cells were pretreated with 1 mM VA and gamma irradiated at different doses. Radiation response was analyzed by clonogenic assay. Cell cycle and cell death were measured 24 and 48 h after irradiation. They microARN (miRNA) expression profile was also evaluated. Results: VA radiosensitized cancer cells as evidenced by the reduction of survival fraction at 2 Gy from 58.4 ± 2.1 to 37.9 ± 2.6 in the treated cells (p