Comparative analysis of a miRNA panel expressed in material obtained from fine needle aspiration biopsy (FNAB) of thyroid nodules and peripheral blood and its application as a diagnostic molecular test

• Grant number: 15/00218-1
• Support Opportunities: Regular Research Grants
• Duration: July 01, 2015 - September 30, 2018
• Field of knowledge: Health Sciences - Medicine - Medical Clinics
• Principal Investigator: Carolina Ferraz da Silva
• Grantee: Carolina Ferraz da Silva
• Host Institution: Faculdade de Ciências Médicas da Santa Casa de São Paulo (FCMSCSP). Fundação Arnaldo Vieira de Carvalho. São Paulo , SP, Brazil
• Associated researchers: Adriano Namo Cury ; Carlos Alberto Longui ; Markus Eszlinger

Abstract

The diagnosis of thyroid nodules is increasing in the last years. Despite some limitations (operator-dependent, ultrasound guided, and discomfort to the patient) fine needle aspiration biopsy (FNAB) is the method of choice for the initial screening to exclude malignancy. However, it is known that approximately 20% of the FNAB samples show indeterminate cytology. With the aim to improve the diagnosis of the indeterminate lesions, several groups started to look for characteristic molecular markers that could differentiate between benign and malignant lesions in FNAB material. MicroRNAs (miRNAs) are small noncoding RNA molecules that regulate the transcription of mRNA and influence the pathogenesis of various tumors by modulating proliferation, apoptosis, migration and cell cycle. Although in several studies an impact of miRNAs in the etiology of thyroid nodules was shown and few groups demonstrated a differential miRNA expression in the peripheral blood, a diagnostic panel with high sensitivity and specificity in blood samples has never been shown up to date. Objective: To define a panel of miRNAs that discriminates benign from malignant nodules in FNAB samples with indeterminate cytology. Moreover, to compare the expression of the miRNA panel in FNAB samples with the expression of these miRNAs in peripheral blood. Expected Results: We expect to define a panel of miRNAsable to differentiate benign from malignant nodules in indeterminate FNAB samples. Furthermore, we expect concordant miRNA expression patterns in FNAB samples and peripheral blood, in order to use peripheral blood for diagnostic testing. Conclusions: On the basis of the definition of a diagnostic miRNA panel to screen indeterminate thyroid samples and the demonstration of a concordant expression of this panel in FNAB samples and peripheral blood, an assay can easily be adapted as routine test in any clinical laboratory, in addition to lowering the cost and decrease the discomfort of the patient. (AU)