Estudo de associação de SNPs com a predisposição ao desenvolvimento de câncer de tireoide em pacientes da Liga Norte-Riograndense Contra o Câncer

Abstract

Thyroid cancer (CT) is the most common endocrine tumor and accounts for 1% of all malignancies. The number of cases diagnosed has been increasing and it is estimated that 212 thousand new cases will appear each year in the world. Currently, there is no study of genetic predisposition to CT performed in the admixture population of Rio Grande do Norte, a place where its incidence is high compared to the Brazilian average. In this way, the present project aims to evaluate the genetic predisposition of the local population to develop the CT, to better understand the pathophysiology of this disease and to establish potential biomarkers of predisposition. To this purpose, histopathological material was selected from the sample bank of the LNRCC Pathology Laboratory to compose the study group, and venous blood from donors from Hemovida blood bank as a control group. Genomic DNA from thyroid gland paraffin blocks and controls blood samples were extracted using the QIAamp® DNA FFPE Tissue kit and QIAamp® genomic DNA kit, respectively. The genotyping of a panel of 84 SNPs was performed using the MALDI-TOF Sequenom® MassARRAY iPLEX Gold Mass Spectrophotometer, in collaboration with the National Center for Genotyping of Santiago de Compostela - Spain. Thirty-six SNPs showed significant differences in their allelic frequencies when compared cases and controls. Of these, 23 SNPs were associated with risk of developing CT, mainly the variants rs2997312 (OR= 6,33), rs7024345 (OR= 2,97), rs10788123 (OR= 2,78), rs116909374 (OR= 3,40) and rs965513 (OR= 2,91) once they confer greater risk to patients. Additionally, 13 SNPs presented as a protective factor for the non-development of this neoplasia. Thus, the present study, unprecedented in the population of Rio Grande do Norte, suggests the association of these SNPs as biomarkers of CT predisposition in this population.