Analysis of p53 codon 72 polymorphism and HPV 5,8 E6 oncoprotein expression in Basal cell carcinoma in Basrah


Background: Two polymorphic forms of the p53 gene that codes either for Arginine or proline at codon 72 were identified, However, this individual might have one of the three genotypes: Arginine/Arginine, Proline/Proline or Arginine /Proline. Previous studies suggested that Arginine form of the p53 codon 72 polymorphism is a risk factor for HPV associated with cervical cancer and has been explored as a possible risk factor for the development of skin cancer in general. This study was aimed to clarify the association of this polymorphism in relation to beta Human Papilloma virus (HPV) 5,8 E6 oncoprotein expression in basal cell carcinoma in Basra, Iraq. Patients & Methods: Blood samples and tissue biopsy from 29 histologically confirmed BCC cases and 31 normal controls were analyzed using polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) method to determine the genotype of p53 codon 72 and conventional PCR for HPV 5 and 8 E6 oncoprotein expression in BCC biopsies. Results: the frequency of Arg/Arg, Pro/Pro or Arg/Pro were 10.3%, 24.1% and 65.5% respectively among patients group and 6.5%, 58.1% and 35.5% among the control group. This result showed a significant increase in the frequency of p53-72 Arginine/Proline heterozygous among BCC cases as compared with controls according to the dominant genetic model (P value =0.007, the Odds ratio = 4.3, 95% CI = (1.4340-13.2059). There was negative expression of HPV 5 and 8 E6 oncoprotein in all the biopsies tested. Conclusion: These finding indicates that the heterozygosity of the p53 codon 72 could be an immunogentic risk factors in the development of BCC, but there was no association detected with HPV5,8 E6 oncoprotein from the examined cases.