Integrity and Quantity of Total Cell-Free DNA in the Diagnosis of Thyroid Cancer: Correlation with Cytological Classification

Abstract

Cell-free DNA (cfDNA) quantity and quality in plasma has been investigated as a non-invasive biomarker in cancer. Previous studies have demonstrated increased cfDNA amount and length in different types of cancer with respect to healthy controls. The present study aims to test the hypothesis that the presence of longer DNA strands circulating in plasma can be considered a biomarker for tumor presence in thyroid cancer. We adopted a quantitative real-time PCR (qPCR) approach based on the quantification of two amplicons of different length (67 and 180 bp respectively) to evaluate the integrity index 180/67. Cell-free DNA quantity and integrity were higher in patients affected by nodular thyroid diseases than in healthy controls. Importantly, cfDNA integrity index was higher in patients with cytological diagnosis of thyroid carcinoma (Thy4/Thy5) than in subjects with benign nodules (Thy2). Therefore, cfDNA integrity index 180/67 is a suitable parameter for monitoring cfDNA fragmentation in thyroid cancer patients and a promising circulating biomarker in the diagnosis of thyroid nodules.

Clinical Significance of Monitoring Circulating Free DNA and Plasma Heat Shock Protein 90alpha in Patients with Esophageal Squamous Cell Carcinoma

“…Previous studies have demonstrated that blood levels of cfDNA and Hsp90α were signi cantly associated with tumor progression [16,18,20,24,25]. For example, the serum concentration of cfDNA has been recognized as a promising candidate biomarker for early detection of colorectal cancer, and plasma Hsp90a levels in patients with advanced lung cancer (stage III-IV) were higher than in patients with early-stage lung cancer (stage I-II) [18,24].…”

“…cfDNA has been identi ed as a biomarker for diagnosis and prognostic prediction of several types of cancer [16][17][18][19][20]. Plasma Hsp90a protein levels have also been reported to be associated with tumor development and treatment responses [24,25].…”

“…Circulating free DNA (cfDNA) corresponds to cell-free DNA fragments circulating in the blood, which is released through necrosis, apoptosis or active secretion by nucleated cells such as lymphocytes [15].Changes in the levels of cfDNA in plasma or serum have been associated with tumour burden and malignant progression in several types of cancer [16][17][18][19][20]. For example, cfDNA concentration is an independent prognostic indicator in lung cancer, and also serves as a biomarker for diagnosis and prognostic prediction of colorectal cancer [17,18].…”

Liquid Biopsy in Patients with Thyroid Carcinoma

“…Salvianti with colleagues proved that quantity of cfDNA with integrity index 180/67 in thyroid cancer patients was higher than in those who had benign thyroid nodules. Therefore, cfDNA could be a suitable marker to diagnose thyroid cancer [20]. On the surface of CTC, epithelial cell adhesion molecule (EpCAM) is found in overexpressed state and therefore can be used for malignant cell visualization from a sample taken by liquid biopsy.…”

Exploration of the Beta-Actin DNA Integrity Index as Early Genetic Marker of Presence of Breast Cancer

“…This biosource may contain mutations, Copy number variations (CNVs) structural variations and modifications in methylation, all of which may provide cell load data and origin of tumor (11). In comparison to programmed cell death in healthy cells, which produces lower and more regular DNA fragments, tumor necrosis triggers DNA release of different sizes ,DNA integrity Index depicted as a proportion of longer to smaller DNA portions can be clinically helpful for cancer identification as a probable serum biomarker (12). Lately, circulating DNA integrity estimated as the proportion of longer to shorter DNA fragments, It was observed to be higher in gynecologically and breast cancer patients than in healthy people (13).…”