Association between the EGF rs4444903 polymorphism and liver cancer susceptibility: a meta-analysis and meta-regression

EGF rs4444903 polymorphism is associated with risk of HCV-related cirrhosis and HBV/HCV-related hepatocellular carcinoma

OBJECTIVE

The epidermal growth factor (EGF) rs4444903 polymorphism is associated with aberrant expression of EGF, which was a characteristic of cirrhotic liver diseases, induces highly malignant hepatocellular carcinoma (HCC). Numerous studies have uncovered the association of this polymorphism with the risk of liver disease, but with inconsistent findings.

MATERIALS AND METHODS

Therefore, this meta-analysis was performed to evaluate whether EGF rs4444903 polymorphism conferred susceptibility to liver disease. Totally 18 eligible articles were identified by searching PubMed, Google, CNKI and EMBASE up to December 1, 2020.

RESULTS

Our results indicated that there was no significant difference in the minor G allele frequency of rs4444903 polymorphism between HBV/HCV carriers and healthy controls. In other words, EGF rs4444903 polymorphism was not associated with the risk of HBV/HCV. Interestingly, this polymorphism increased the risk of liver cirrhosis in the controls with HCV infection. Additionally, EGF rs4444903 polymorphism is associated with the increased risk of HCC under the five models. Subgroup analysis by ethnicity shows that rs4444903 polymorphism intensifies the risk of HCC among Asians and Caucasians. Strong correlation is also reported in controls with cirrhosis or HCV infection and studies using PCR-RFLP genotyping.

CONCLUSIONS

The study supports that EGF rs4444903 polymorphism is a genetic contributor to liver cirrhosis and HCC in the overall population. Nevertheless, this conclusion must be confirmed by larger studies with more diverse ethnic populations.

Host nucleotide polymorphism in hepatitis B virus-associated hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is etiologically linked with hepatitis B virus (HBV) and is the leading cause of death amongst 80% of HBV patients. Among HBV affected patients, genetic factors are also involved in modifying the risk factors of HCC. However, the genetic factors that regulate progression to HCC still remain to be determined. In this review, we discuss several single nucleotide polymorphisms (SNPs) which were reportedly associated with increased or reduced risk of HCC occurrence in patients with chronic HBV infection such as cyclooxygenase (COX)-2 expression specifically at COX-2 -1195G/A in Chinese, Turkish and Egyptian populations, tumor necrosis factor α and the three most commonly studied SNPs: PAT-/+, Lys939Gln (A33512C, rs2228001) and Ala499Val (C21151T, rs2228000). In genome-wide association studies, strong associations have also been found at loci 1p36.22, 11q22.3, 6p21 (rs1419881, rs3997872, rs7453920 and rs7768538), 8p12 (rs2275959 and rs37821974) and 22q11.21. The genes implicated in these studies include HLA-DQB2, HLA-DQA1, TCF19, HLA-C, UBE2L3, LTL, FDX1, MICA, UBE4B and PG. The SNPs found to be associated with the above-mentioned genes still require validation in association studies in order to be considered good prognostic candidates for HCC. Screening of these polymorphisms is very beneficial in clinical experiments to stratify the higher or lower risk for HCC and may help in designing effective and efficient HCC surveillance programs for chronic HBV-infected patients if further genetic vulnerabilities are detected.

The functional EGF+61 polymorphism and nonsyndromic oral clefts susceptibility in a Brazilian population

Nonsyndromic oral clefts are considered a problem of public health in Brazil, presenting a multifactorial etiology that involves genetic and environmental components, such as maternal alcohol consumption. Several candidate genes have been investigated to identify some association with nonsyndromic clefts risk. The epidermal growth factor (EGF) gene is implicated in the normal craniofacial development and its functional +61 A>G polymorphism has been related to cancer susceptibility. It has been suggested that cancer and oral clefts may share the same molecular pathways.Objective Our goal was to evaluate the association between the EGF+61 A>G polymorphism and nonsyndromic oral clefts susceptibility.Material and Methods The case-control study included 218 cleft cases and 253 controls from Brazil. The control group was comprised of individuals without congenital malformations, dental anomalies and family history of clefts. The cleft phenotypes and subphenotypes were determined based on clinical examination. Genomic DNA was extracted from oral mucosa cells obtained by mouthwash. The EGF+61 A>G polymorphism genotype was determined by polymerase chain reaction-restriction fragment length polymorphism.Results We noticed the association between maternal alcohol consumption during pregnancy and cleft occurrence. The A allele and AA genotype were over-represented in cleft cases compared with control group when we considered the bilateral cleft lip with or without cleft palate (CL±P) cases, cleft cases with tooth agenesis and cleft cases presenting family history of cleft, but the differences were not statistically significant. Contradictorily, the G allele was higher in cleft palate only (CP) cases than in control group, showing a borderline p value. Comparing the different cleft phenotypes, we observed statistical differences between CP and CL±P cases. Our data suggest the EGF+61 A>G polymorphism was not related with nonsyndromic oral clefts susceptibility in a Brazilian population, but supported the different genetic background between CL±P and CP. Moreover, we confirmed the potential effect of maternal alcohol intake on cleft risk in our population.