Polymorphisms of vascular endothelial growth factor on prognosis in hepatocellular carcinoma patients receiving transcatheter arterial chemoembolization treatment

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

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.

GSTM1 and GSTT1 copy number variants and the risk to Thai females of hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) is a common malignancy found throughout the world that most often occurs in males. The cancer is associated with many risk factors such as viral infection, cirrhosis, alcohol, smoking, and fungal toxins. GSTM1 and GSTT1 are detoxification enzymes activated by the cleansing of carcinogenic compounds. Low DNA copy numbers of Glutathione S-transferases M1 and T1 result in a loss of enzyme activity, which causes carcinogenesis factors. DNA copy number variants (CNVs) were determined to compare the differences between the frequencies of GSTM1 and GSTT1 in a control group and patients. Then, the association of these genes with the pathological/survival status of HCC patients was investigated.

Methods

Forty-nine Thai HCC patients' DNA and the genomic DNA of 66 healthy controls were investigated for GSTM1 and GSTT1 CNVs by real-time polymerase chain reaction (PCR). Then, the correlations between GSTM1 and GSTT1 patients' CNVs, the control group, and clinico-pathological parameters were determined.

Results

The results show that were no differences between the CNVs of GSTM1 and GSTT1 in the controls and patients (P≥0.05). Only GSTT1 genotypes 0/0 correlated to an increase in the risk of hepatocellular carcinogenesis (OR value was 1.88). GSTM1 CNVs were associated with the gender of patients (P=0.002). However, no correlations were found between GSTT1 CNVs and any of the clinico-pathological parameters.

Conclusions

The results suggest that only GSTT1 CNVs are associated with increased risk factors of HCC in Thais. GSTM1 copy numbers had a dominant correlation with female HCC patients.

Association of VEGFA polymorphisms with susceptibility and clinical outcome of hepatocellular carcinoma in a Chinese Han population

Vascular endothelial growth factor A (VEGFA) is an important angiogenesis regulator, which plays an important role in angiogenesis and progression of tumor, including hepatocellular carcinoma (HCC). We aimed at determining whether single nucleotide polymorphisms of VEGFA gene influence the development and clinical outcomes of HCC. We analyzed four potential functional polymorphisms (936C/T, 634G/C, 1612G/A, 2578C/A) of VEGFA gene in 476 HCC patients and 526 controls using matrix-assisted laser desorption ionization time-of-flight mass spectrometry method. Serum VEGF levels were measured by enzyme-linked immunosorbent assay. The Kaplan-Meier methods with log-rank test and Cox regression models were used to compare survival of resected HCC patients according to the genotype. We found that only the VEGFA 2578C/A polymorphism was significantly associated with decreased risk of HCC (AA/AC vs. CC; adjusted OR = 0.69, 95% CI = 0.51-0.93). Furthermore, the 2578C/A polymorphism was associated with significantly decreased postoperative recurrence (AA/AC vs. CC, adjusted OR = 0.51; 95% CI, 0.29-0.88) and improved overall survival (AA/AC vs. CC, adjusted HR = 0.27, 95% CI = 0.13-0.52) of resected HCC patients. In addition, the VEGF serum levels in HCC patients were significantly higher than those in healthy controls, although no significant association between VEGFA genotype and serum levels of VEGF was observed. These results suggest that the VEGFA 2578 C/A polymorphism may play a potential role in the development and clinical outcome of HCC among Chinese Han population.

VEGF Polymorphisms Related to Higher Serum Levels of Protein Identify Patients with Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common primary neoplasia of the liver. Major risk factors for hepatocellular carcinoma include chronic liver diseases, carcinogenic agents, and genetic alterations as well as vascular endothelial growth factor (VEGF) involved in angiogenesis process. The aim of this study was to evaluate the association of VEGF-A (C936T and A1154G) with HCC and cirrhosis, in addition to serum levels of VEGF, clinical profile, lifestyle habits, and comorbidities. A total of 346 individuals were studied: 102 with HCC (G1), 117 with cirrhosis (G2), and 127 controls (G3). Polymorphisms were analysed by PCR/RFLP and serum levels of VEGF by ELISA. Alpha error was set at 5%. The wild-type genotype of both polymorphisms prevailed (P > 0.05). In G1, 23% of the patients died, with no relation to genetic profile (P > 0.05). Increased VEGF level was observed in G1 and G3, related to the mutant allele of VEGF-C936T and VEGF-A1154G, respectively, and compared with the wild-type genotype (P = 0.0285; P = 0.0284, resp.) as well as G1 versus G2 and G3 for VEGF-C936T and G1 versus G2 for VEGF-A1154G (P < 0.05 for both). In conclusion, there is a relationship between mutant alleles of VEGF-C936T and VEGF-A1154G polymorphisms and higher VEGF level, making them potential markers for HCC.