title: RARβ2 gene methylation level in the circulating DNA from blood of patients with lung cancer.
abstract: Alterations in the patterns of DNA methylation are among the earliest and most common events in tumorigenesis. Epigenetic changes were shown to be detectable in DNA, circulating in blood (cirDNA) of cancer patients, indicating the resources to create the minimally invasive diagnostic tests based on tumor-specific DNA markers. RARβ2 methylation level was significantly increased in plasma cirDNA and cell surface-bound cirDNA (csb-cirDNA) from patients with non-small cell lung cancer compared with healthy individuals (7620 and 1083 copies/ml in the csb fractions, 3589 and 1068 copies/ml in the blood plasma; P=0.003 and 0.001). The cell-bound-to-cell-free RARβ2 methylation ratio was found to be elevated in patients with non-small cell lung cancer compared with control (2.12 and 1.01, respectively; P=0.023). RARβ2 methylation level in csb-cirDNA and plasma cirDNA was higher in stage III patients compared with stage I-II patients (P=0.02 and 0.03). In the subgroup of patients with squamous cell carcinoma, RARβ2 methylation level in the cbs-cirDNA was higher compared with patients with adenocarcinoma (P=0.04). Epigenetic alterations of tumor suppressor gene RARβ2 in the total cirDNA (plasma cirDNA and csb-cirDNA) were found to be associated with lung cancer progression. The data obtained indicate that cirDNA-based testing provides a valuable source for subsequent verification of methylated DNA markers for lung cancer diagnostics and prognosis.
authors.affiliation: Cancer Research Institute, Siberian Division of the Russian Academy of Medical Sciences, Tomsk, Tomsk Oblast, Russia. anastasia-ponomaryova@rambler.ru
authors.forename: Anastasia A
authors.initials: AA
authors.lastname: Ponomaryova
authors.forename: Elena Yu
authors.initials: EY
authors.lastname: Rykova
authors.forename: Nadezda V
authors.initials: NV
authors.lastname: Cherdyntseva
authors.forename: Tatiana E
authors.initials: TE
authors.lastname: Skvortsova
authors.forename: Alexey Yu
authors.initials: AY
authors.lastname: Dobrodeev
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Zav'yalov
authors.forename: Sergey A
authors.initials: SA
authors.lastname: Tuzikov
authors.forename: Valentin V
authors.initials: VV
authors.lastname: Vlassov
authors.forename: Pavel P
authors.initials: PP
authors.lastname: Laktionov
mesh_terms: D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood* / Q000235:genetics* / Q000473:pathology; D004247:DNA / Q000097:blood* / Q000235:genetics; D019175:DNA Methylation / Q000235:genetics*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000097:blood* / Q000235:genetics* / Q000473:pathology; D008297:Male; D018168:Receptors, Retinoic Acid / Q000097:blood* / Q000235:genetics*; D015854:Up-Regulation / Q000235:genetics
chemical_list: D018168:Receptors, Retinoic Acid; C540966:retinoic acid receptor, beta2, human; D004247:DNA