Gene Cell Tissue. 2020 July; 7(3):e103317. Published online 2020 July 25. doi: 10.5812/gct.103317. Research Article Detection of R282w P53 Gene Mutation on Exon 8 in Gastric Cancer Patients in Southwest Iran Sajad Afrouz 1 , Mohammad Amin Ghatee 2, * , Amroallah Roozbehi 2 and Mohammad Hossein Sangtarash 1 1 Department of Biological Sciences, University of Sistan and Baluchistan, Zahedan, Iran 2 Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran * Corresponding author: Ph.D., Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran. Email: ghateea1980@gmail.com Received 2020 April 04; Revised 2020 June 15; Accepted 2020 June 27. Abstract Background: Gastric adenocarcinoma is the most common type of gastric cancer all around the world. The epithelial cells of stom- ach tissue are influenced by environmental factors and genetic disorders. P53 is the most remarkable gene that controls the growth of cells. Mutation in some nucleotides of the P53 gene increases the genetic instability and is assumed as an important prognostic factor in gastric cancer. More than 90% of mutations occur in the exons 5-8 of p53. Objectives: This study was conducted in Kohgiluyeh and Boyer Ahmad (K&B) province (Southwest Iran) to determine the rate of R282W P53 gene mutation of exon 8 in gastric cancer. Methods: This case-control study was conducted on 90 subjects that were divided into two groups (each including 45 patients and 45 controls). The samples were randomly collected from the tissue bank of the pathology laboratory in Yasuj city and then were transferred to the Cellular and Molecular Research Center. DNA extraction was performed by the DNA extraction kit. Molecular analysis on exon 8 was performed by the PCR-RFLP method and using the MspI restricting enzyme. Data were analyzed by descriptive statistics and bivariate correlation tests. Results: No difference was found between the two groups concerning age, gender, and education level. The prevalence of R282W P53 gene mutation on exon 8 in the cancer group was 17.8% (8/45), while no mutation was found in the control group. Conclusions: According to the results, the R282W P53 gene mutation on exon 8 may play an important role in the development of gastric cancer in Yasuj district, Southwest Iran. Keywords: P53, PCR, RFLP, Exon 8, R282W 1. Background Gastric cancer (GC) is the second leading cause of cancer-related mortality (1). Its incidence shows a wide ge- ographical variation. About half of the total gastric cancer load occurs in East Asia, particularly in China and Japan (2). The low-risk areas include Southern Asia, and North and East Africa (3). Although the incidence of GC is gradually decreasing in many parts of the world, it is still the most common malignancy in Iran (4). There are several inter- mediate and low-risk populations in geographical areas, while the northern and northwestern regions are high- risk areas for gastric cancer (4). The mean incidence rate of stomach cancer is 10.5 - 12 (5). Based on the previous studies, the incidence of stomach cancer is rising in K&B province, including in Yasuj district (6). Regarding the marked variation of gastric cancer risk in different geographical areas and striking differences in frequency of possible environmental and ethnic risk fac- tors, research on the gastric cancer etiology in each pop- ulation should be considered as a priority (3). GC is a multifactorial disease that develops due to con- tinuous cell damage caused by life-long exposure to differ- ent predisposing factors, including carcinogens (7-9). Epi- genetic alteration involving tumor suppressor genes mu- tations, DNA repair genes, and loss of heterozygosis (LOH) A may cause cancerous cell mutation (10, 11). Recent stud- ies have revealed that p53 mutations are biologically and clinically distinct. Genetic alterations in the TP53 gene are fundamental events in both early-stage and advanced stomach tumors (12, 13). Approximately, over 50% of hu- man cancers carry a loss of function mutations in the p53 gene (14) in which, 95% of TP53 mutations occur within the genomic region encoding the sequence-specific DNA- binding domain of TP53 protein (exons 4-9) (15-17). A mis- Copyright © 2020, Gene, Cell and Tissue. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/) which permits copy and redistribute the material just in noncommercial usages, provided the original work is properly cited.