Glutathione S-Transferase P1 Polymorphism on Exon 6 and Risk of Hepatocellular Carcinoma in Thai Male Patients

Abstract

INTRODUCTION: Hepatocellular carcinoma (HCC) is the fifth most common malignancy and the fourth leading cause of cancer-related deaths worldwide. HCC cases are two to four times more common in males than in females, and the highest incidence is found in Asia and Sub-Saharan Africa. This gender disparity is the result of different behavioral risk factors, such as smoking and drinking alcohol. Glutathione S-Transferase P1 (GSTP1) is an enzyme that is involved in the detoxification of carcinogenic electrophiles. GSTP1 codon 105 in exon 5 and codon 114 in exon 6 polymorphisms result in decreased enzyme detoxification activity, which is the cause of many cancers. OBJECTIVES: This study aims to investigate the associations between GSTP1 polymorphism, HCC patients, and the risk factors for HCC. It is hoped that this research will provide useful knowledge on the effects of genetic GSTP1 polymorphism in Thai HCC patients. METHODS: DNA from 44 Thai HCC patients and 52 healthy controls was analyzed for GSTP1 exon 5 and exon 6 polymorphisms by PCR-RFLP. The associations between GSTP1 polymorphism, the control group, and clinicopathological parameters were determined. RESULTS: The results show that GSTP1 exon 6 polymorphism genotypes (C/T) were correlated with an increased risk of HCC susceptibility (OR = 4.40). Moreover, exon 6 polymorphism genotypes (C/T) were associated with the gender of patients (p = 0.015), but no relationships were found between GSTP1 exon 5 polymorphism and the clinicopathological data of patients. CONCLUSIONS: The results suggest that the GSTP1 exon 6 polymorphism genotype was associated with an increase in the risk of HCC in male patients and that it tended to be related to cancer differentiation. No association was found between GSTP1 exon 5 polymorphism and the risk of HCC.