Correlation of cell-free DNA plasma concentration with severity of non-alcoholic fatty liver disease

J Transl Med. 2017 May 19;15(1):106. doi: 10.1186/s12967-017-1208-6.

Abstract

Background: The assessment of fibrosis and inflammatory activity is essential to identify patients with non-alcoholic fatty liver disease (NAFLD) at risk for progressive disease. Serum markers and ultrasound-based methods can replace liver biopsy for fibrosis staging, whereas non-invasive characterization of inflammatory activity remains a clinical challenge. Cell-free DNA (cfDNA) is a novel non-invasive biomarker for assessing cellular inflammation and cell death, which has not been evaluated in NAFLD.

Methods: Patients and healthy controls from two previous studies were included. NAFLD disease activity and severity were non-invasively characterized by liver stiffness measurement (transient elastography, TE) including steatosis assessment with controlled attenuation parameter (CAP), single-proton magnetic resonance spectroscopy (1H-MRS) for determination of hepatic fat fraction, aminotransferases and serum ferritin. cfDNA levels (90 and 222 bp fragments) were analyzed using quantitative real-time PCR.

Results: Fifty-eight NAFLD patients (age 62 ± 11 years, BMI 28.2 ± 3.5 kg/m2) and 13 healthy controls (age 38 ± 12 years, BMI 22.4 ± 2.1 kg/m2) were included. 90 bp cfDNA levels were significantly higher in NAFLD patients compared to healthy controls: 3.7 (1.3-23.1) vs. 2.9 (1.4-4.1) ng/mL (p = 0.014). In the NAFLD cohort, circulating cfDNA correlated significantly with disease activity and severity, especially in patients with elevated liver stiffness (n = 13, 22%) compared to cases with TE values ≤7 kPa: cf90 bp 6.05 (2.41-23.13) vs. 3.16 (1.29-7.31) ng/mL (p < 0.001), and cf222 bp 14.41 (9.27-22.90) vs. 11.32 (6.05-18.28) ng/mL (p = 0.0041).

Conclusions: Cell-free DNA plasma concentration correlates with established non-invasive markers of NAFLD activity and severity. Therefore, cfDNA should be further evaluated as biomarker for identifying patients at risk for progressive NAFLD.

Keywords: Cell-free DNA; Controlled attenuation parameter; MR-spectroscopy; Non-alcoholic fatty liver disease; Non-alcoholic steatohepatitis; Transient elastography.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anthropometry
  • Biomechanical Phenomena
  • Cell-Free Nucleic Acids / blood*
  • Cohort Studies
  • Female
  • Humans
  • Liver / pathology
  • Liver / physiopathology
  • Male
  • Metabolic Syndrome / blood
  • Metabolic Syndrome / complications
  • Metabolic Syndrome / physiopathology
  • Middle Aged
  • Non-alcoholic Fatty Liver Disease / blood*
  • Non-alcoholic Fatty Liver Disease / complications
  • Non-alcoholic Fatty Liver Disease / pathology*
  • Severity of Illness Index*

Substances

  • Cell-Free Nucleic Acids