Ovarian cancer and genetic susceptibility: association of A61G polymorphism in the EGF gene.

Growth factors play an essential role in regulating cellular proliferation, and lack of control is characteristic of malignant development. The epidermal growth factor (EGF) gene codifies a growth factor that binds to the EGF receptor (EGFR), which is involved in activating pathways that promote cellular proliferation, survival, migration and differentiation. The purpose of this study was to appraise the association between EGF gene A61G polymorphism with ovarian cancer susceptibility. A total of 564 DNA samples were analysed from 175 women with ovarian cancer and 389 women without cancer, through PCR-RFLP. We found a decreased risk for developing ovarian cancer in GG carriers compared to AA carriers (OR = 0.46, CI = 0.25-0.83, P = 0.010). The seemingly protective role in GG carriers was observed in women under 53 years of age (OR = 0.38, CI = 0.16-0.86, P = 0.011) and in patients diagnosed with advanced stage disease (OR = 0.38, CI = 0.18-0.81, P = 0.012). Allelic comparison evidenced similar results, with decreased risk for G allele. We further observed a linear trend for G allele in cancer risk. Moreover, we analysed the influence of genotypes in the time to onset of the disease and observed that GG carriers had ovarian cancer later than AA carriers (P = 0.035). We hypothesize that this polymorphism confers protection for ovarian cancer development.