Altered levels of circulating nuclear and mitochondrial DNA in patients with Papillary Thyroid Cancer

Sci Rep. 2019 Oct 8;9(1):14438. doi: 10.1038/s41598-019-51000-7.

Abstract

Papillary thyroid cancer is the most common thyroid cancer type. However, diagnostics based on fine needle biopsy cannot make a definitive diagnosis in 25% of thyroid nodules. Additionally, approximately 70% to 80% of thyroid lobectomies performed just for diagnostic purposes are benign. Despite this, biopsy still remains the main method of evaluation of thyroid nodules. Cell-free DNA (cf-DNA) measurement could give a new diagnostic opportunities which may reduce the number of unnecessary thyroid procedures. In this study, using a qPCR, we have examined the nuclear cf-DNA and mitochondrial cf-DNA in the plasma of 32 patients. We have found that the level of nuclear cf-DNA is almost 2-fold increased (median 3 089 vs. 1 872, p = 0.022), whereas mitochondrial cf-DNA content was significantly decreased in respect to healthy controls (median 44 992 vs. 92 220, p = 0.010). The ROC curve analysis showed high specificity for nuclear cf-DNA and mitochondrial cf-DNA, which may serve as a useful tool to decrease the number of unneeded surgeries. Our study reports the first epidemiological evidence for lower mitochondrial cf-DNA content in the patient group, what suggests that apart from nuclear cf-DNA also mitochondrial cf-DNA is affected by disease development.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Cell Nucleus
  • Cell-Free Nucleic Acids / blood
  • DNA / blood*
  • DNA, Mitochondrial / blood*
  • Female
  • Humans
  • Lymph Nodes
  • Male
  • Middle Aged
  • ROC Curve
  • Real-Time Polymerase Chain Reaction
  • Thyroid Cancer, Papillary / blood*
  • Thyroid Cancer, Papillary / genetics
  • Thyroid Neoplasms / blood*
  • Thyroid Neoplasms / genetics
  • Young Adult

Substances

  • Cell-Free Nucleic Acids
  • DNA, Mitochondrial
  • DNA