Rap2AIs Upregulated in Invasive Cells Dissected from Follicular Thyroid Cancer

Abstract

The development of molecular biomarkers (BMs) of follicular thyroid carcinoma is aimed at advancing diagnosis of follicular neoplasm, as histological examination of those tumors does not lend itself to definitive diagnosis of carcinoma. We assessed the relative levels of expression of 6 genes:CCND2, PCSK2, PLAB, RAP2A, TSHR, and IGF-1Rin archived thyroid tissue. The quantitative real-time PCR analysis revealed a significant change in 3 genes:PSCK2(a 22.4-fold decrease, ),PLAB(an 8.3-fold increase, ), andRAP2A(a 6.3-fold increase, ) in carcinoma compared with adenoma. Expression ofPCSK2was equally low,PLABwas equally high, whereasRAP2Aexpression was significantly higher (25.9-fold, ) in microdissected carcinoma cells that have invaded through the thyroid capsule and entered blood vessels than in thyroid tumor cells growing under the capsule. Thus,RAP2Aappeared as a unique and worthy of further evaluation candidate BM associated with invasion of thyroid follicular cells.