PON I and GLO I Gene Polymorphisms and Their Association with Breast Cancer: A Case-Control Study in a Population from Southern Italy

Background: Many factors may play a role in the susceptibility to the breast cancer. Oxidative stress may be one of these. Polymorphisms of genes such as paraoxonase I (PON I) and glyoxalase I (GLO I) may influence individual susceptibility to breast cancer. In the present study, we have conducted a case-control study in order to examine the possible relation between GLO I A111E and PON I Q192R/L55M polymorphisms with the risk of breast cancer. Methods: The three polymorphisms were characterized in 144 breast cancer postmenopausal patients and in 152 healthy women by PCR/RFLP methods using DNA from lymphocytes. Results: Among the three polymorphisms, only PON I L55M polymorphism was associated with the patient’s age and, more precisely, the heterozygous genotype that is more represented in women aged between 51-69 years. In addition, we found that individuals with the PON192 Q/R - R/R genotypes and PON55 L/M - M/M genotypes had a significantly higher risk of breast cancer compared with the other genotypes. The genotypes PON55 L/M and PON192 Q/R showed significant association with lymph nodes positivity (p < 0.001) and with a high nuclear grading (p < 0.001), respectively. Conversely the genotypes GLO I AE/EE were associated with a low nuclear grading. Conclusions: We believe that the combination of the three polymorphisms may be a more predictive factor for the risk of this neoplasia in each single examined case.