en 32431794 <p>Background: Most of Gastric Cancer (GC) patients are diagnosed at an advanced stage with poor prognosis. Hypermethylations of several tumor suppressor genes in cell-free DNA of GC patients have been previously reported. In this study, an attempt was made to investigate the methylation status of <em>P16</em>, <em>RASSF1A</em>, <em>RPRM</em>, and <em>RUNX3 </em>and their potentials for early diagnosis of GC.</p> <p>Methods: Methylation status of the four tumor suppressor genes in 96 plasma samples from histopathologically confirmed gastric adenocarcinoma patients (Stage I-IV) and 88 healthy controls was determined using methylation-specific PCR method. Receiver operating characteristic curve analysis was performed and Area Under the Curve (AUC) was calculated. Two tailed p&lt;0.05 were considered statistically significant.</p> <p>Results: Methylated <em>P16</em>, <em>RASSF1A</em>, <em>RPRM</em>, and <em>RUNX3</em> were significantly higher in the GC patients (41.7, 33.3, 66.7, and 58.3%) compared to the controls (15.9, 0.0, 6.8, and 4.5%), respectively (p&lt;0.001). Stratification of patients showed that <em>RPRM</em> (AUC: 0.70, Sensitivity: 0.47, Specificity: 0.93, and p&lt;0.001) and <em>RUNX3 </em>(AUC: 0.77, Sensitivity: 0.59, Specificity: 0.95, and p&lt;0.001) had the highest performances in detection of early-stage (I+II) GC. The combined methylation of <em>RPRM </em>and <em>RUNX3 </em>in detection of early-stage GC had a higher AUC of 0.88 (SE=0.042; 95% CI:0.793&ndash;0.957; p&lt;0.001), higher sensitivity of 0.82 and reduced specificity of 0.89.</p> <p>Conclusion: Methylation analysis of <em>RPRM </em>and <em>RUNX3 </em>in circulating cell free-DNA of plasma could be suggested as a potential biomarker for detection of GC in early-stages.</p> Biomarkers, Cell-free DNA, Gastric cancer, DNA methylation 99 106 https://www.ajmb.org/En/Article.aspx?id=10370 https://www.ajmb.org/PDF/En/FullText/10370.pdf KioomarsSaliminejadReproductive Biotechnology Research Center, Avicenna Research Institute (ACECR), Tehran, Iran393ShahrzadSoleymani FardHematology, Oncology and Stem Cell Transplantation Research Center, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran92Hamid RezaKhorram KhorshidGenetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran, Tehran, Iran42MarjanYaghmaeiHematology, Oncology and Stem Cell Transplantation Research Center, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran373HabibollahMahmoodzadehDepartment of Surgery, Cancer Institute, Imam Khomeini Hospital, Tehran, University of Medical Sciences, Tehran, Iran31506Seyed AsadollahMousaviHematology, Oncology and Stem Cell Transplantation Research Center, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran31507Seyed HamidollahGhaffari31598