Lack of Mutation in the Hot Spot Region of the Human P53 Gene in a Number of Iranian Hepatocellular Carcinoma Patients

Background and Objectives: Mutation directed inactivation of the tumor suppressor gene p53 have been found in countries with high frequency for hepatocellular carcinomas (HCCs). Our goal in the present study was screening of the p53 gene in tumor tissues from HCC affected individuals in southwest Iran for putative mutations in exons 7 and 8 that are known as hot spot regions. Materials & Methods: A total of 25 archival formalin fixed paraffin embedded samples prepared from 1997 to 2006 were collected from hospitals in southwest and northwest of Iran. We examined the codon 249 within the exon 7 using RFLP as well the full-length sequencing of exons 7 and 8. Results: The samples were diagnosed as HCC and classified in four groups, well differentiated (39%), moderately differentiated (54%), poorly differentiated (4.5%) and undifferentiated (2.5%). The hepatitis B virus (HBV) was detected in 16% (n=7) and 11% (n=5) of patient’s sera that were affected with liver cirrhosis. No patient was infected with hepatitis C virus. However, in one tumor sample a homozygote mutation was detected at codon 302. Conclusion: In contrast to the numerous reports, particularly from Asian countries, the selected HCC patients in this study show a very low mutation rate in the hot spot regions of the p53 gene. However, further mutation studies have to be conducted for the whole length of the p53 gene for more evaluation.