en زیست شناسی ملکولی Molecular Biology مقالات اصلی Original Article <div style="text-align: justify;"><strong><em>Background:</em></strong> Epigenetic changes in CpG islands of the promoter regions of homeostasis-related genes, including nuclear factor erythroid 2-related factor 2 (<em>NRF2</em>), have been shown to hold a significant role in the development of colorectal cancer. Therefore, we aimed to examine the DNA demethylation pattern of the <em>NRF2</em> promoter region in cancerous lesions from patients with colorectal cancer and the association of methylation status with clinicopathological features in the Iranian population.<br> <br> <strong><em>Methods:</em></strong> In this cross-sectional study, 114 colorectal tissue samples were collected. These samples included: 34 tumour tissue samples, 60 precancerous polyps, and 20 normal tissue samples. The promoter methylation status of the <em>NRF2</em> gene was examined using methylation-specific PCR. Additionally, the relationship between the methylation status and the clinicopathological features was investigated.<br> <br> <strong><em>Results</em></strong><strong><em>:</em></strong> The frequency of <em>NRF2</em> demethylation in the tumour samples was significantly higher compared to the polyp tissues (p= 0.003) and normal tissue (p= 0.009), indicating that cancerous colorectal tissues exhibit increased demethylation of the <em>NRF2</em> promoter. After examining the demethylation status of tissue samples, the clinicopathological features were compared to the demethylation results. No significant association was found between <em>NRF2</em> promoter demethylation and the clinicopathological features of patient samples.<br> <br> <strong><em>Conclusions: </em></strong>Our findings suggest that the epigenetic modifications leading to <em>NRF2 </em>demethylation found in colorectal tumour samples may contribute to cancer progression from precancerous polyps to cancerous lesions.</div> Colorectal Cancer, Epigenetic, Methylation-specific PCR, NRF2. 33 39 http://rbmb.net/browse.php?a_code=A-10-313-2&slc_lang=en&sid=1 Zahra Taheri zahra_taheri_2005@yahoo.com 100319475328460017489 100319475328460017489 No Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran. Hamid Asadzadeh Aghdaei hamid.assadzadeh@gmail.com. 100319475328460017490 100319475328460017490 No Basic and Molecular Epidemiology of Gastroenterology Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran Shiva Irani shi_irani@yahoo.com 100319475328460017491 100319475328460017491 Yes Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran. Mohammad Hossein Modarressi modaresi@tums.ac.ir 100319475328460017492 100319475328460017492 No Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Zahra Noormohammadi marjannm@yahoo.com 100319475328460017493 100319475328460017493 No Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.