Evaluation of gene RASSF2 expression and methylation in tumor tissue and marginal tumor of Lung cancer patients

Abstract

Different types of malignancies are known as one of the most important causes of death in the world, among them, lung cancer is the most common cancer among both males and females, and according to the biology and pathogenesis of this disease, it has It is the highest death rate among all types of cancer. One of the most important known changes in the process of cancers, especially lung cancer, is epigenetic changes, especially in the level of DNA methylation, which causes the progression of this disease by changing the expression of various genes, especially tumor suppressors and oncogenes. The RAS protein family is one of the most well-known oncogenes. These GTPases play a key role in the development and progression of cancer. Among the most important suppressors of the Ras GTPase family, they are included in the group of tumor suppressor genes due to their function. The protein family is RASSF (Ras Association Domain Family Member), this protein family has 10 members, and RASSF2 is one of the most well-known members of this family. In vitro studies have previously proven the role of this gene in inhibiting cell growth and inducing apoptosis. Based on the evidence of most of the tumors, we see the reduction or loss of RASSF2 function. In this study, the expression level of this gene and its methylation in patients with lung cancer and their relationship with the clinical variables of the patients were investigated. Methods: In this research, 50 tumor tissue samples and 50 tumor margin samples from NSCLC lung cancer patients were collected from the same patients, then to evaluate gene expression, RNA was first extracted from the tissues, and after cDNA synthesis from It was used to investigate changes in RASSF2 gene expression by Real Time PCR. In the second part of the investigation, DNAs were first extracted, and after bisulfite treatment, the methylation level of the investigated gene was performed using the semi-quantitative MS-HRM method. In this study, pvalue<0.05 was considered as a significant level in all statistical tests. Results: The obtained results have shown a significant increase in methylation in the promoter region of the RASSF2 gene in tumor samples compared to healthy samples and a significant decrease in the expression of this gene in tumor samples compared to margin samples. Also, changes in the expression and methylation of this gene are related to some pathological characteristics of patients such as metastasis.