Functional polymorphism in EGF gene and malignant melanoma

Lack of association between EGF +61A>G polymorphism and melanoma susceptibility in Caucasians: a HuGE review and meta-analysis

Emerging evidence showed that the common polymorphism (+61A>G, rs4444903) in the promoter region of epidermal growth factor (EGF) gene might be associated with melanoma susceptibility in humans. But individually published results are inconclusive. The aim of this Human Genome Epidemiology (HuGE) review and meta-analysis is to derive a more precise estimation of the association between EGF +61A>G polymorphism and melanoma risk. The PubMed, Embase, Web of Science and CBM databases were searched for all articles published up to July 1st, 2012. Seven case-control studies were included with a total of 2367 melanoma cases and 4184 healthy controls. Meta-analysis results showed that there was no significant relationship between EGF +61A>G polymorphism and the risk of melanoma (G vs A: odds ratio [OR]=1.08, 95% confidence interval [CI]: 0.91-1.28, P=0.386; GG+AG vs AA: OR=1.05, 95%CI: 0.88-1.26, P=0.580; GG vs AA+AG: OR=1.10, 95%CI: 0.81-1.49, P=0.552; GG vs AA: OR=1.06, 95%CI: 0.80-1.41, P=0.700; GG vs AG: OR=1.12, 95%CI: 0.81-1.56, P=0.494). Further subgroup analyses based on source of controls, country, detection samples, genotype methods, and Breslow thickness of tumor, we also found no significant association between EGF +61A>G polymorphism and melanoma risk. In conclusion, this meta-analysis indicates that EGF +61A>G polymorphism might not be a primary determinant in melanoma development and progression; EGF gene might be expected to interact with other genes in different signaling pathways to initiate and promote the carcinogenic process.

Common genetic polymorphisms and prognosis of sporadic cancers: prostate cancer as a model

To date, most molecular epidemiological studies on gene polymorphisms in cancer have focused on the risk of development and susceptibility to cancer. However, interindividual genetic variation may contribute greatly to the treatment outcome and prognosis of cancer by affecting the interaction between cancer cells and hormones, growth factors and factors influencing the tumor microenvironment. In prostate cancer, several recent molecular epidemiological studies suggested the possibility of predicting treatment outcome and prognosis using genetic polymorphisms. Candidate genes are hormone-related, oncogenes, tumor-suppressor and cell cycle-growth control-related genes, as well as genes related to immune response, inflammatory change, neovasculization, and the extracellular matrix, genes involved in drug and xenobiotic metabolism and genes involved in DNA repair and genome stability. There remain a huge number of candidate genes whose polymorphisms may affect the progression and treatment outcome of various kinds of cancer, including that of prostate cancer.