Influence of the D104N do gene COL18A1 gene in sporadic breast cancer susceptibility

Author(s)

Gustavo Jacob Lourenço

• Document type: Master's Dissertation
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Ciências Médicas
• Defense date: 2006-01-26

Examining board members

Carmen Silvia Passos Lima; Mônica Barbosa de Melo; Luiz Carlos Teixeira

• Advisor: Carmen Silvia Passos Lima

Abstract

Angiogenesis is an important step in sporadic breast cancer (SBC) development and progression There is evidence that neoplastic cells play a role in the generation of endogenous antiangiogenic proteins, such as endostatin (ES). ES is codified by the COL18A1 gene. Recently, a COL18A1 polymorphism (D104N) was associated with increased risk for the prostatic adenocarcinoma. Considering that it is unknown whether the D104N polymorphism of the COL18A1 gene alters the risk for SBC, this was the aim of this study. Thus, genomic DNA from peripheral blood of 181 SBC women and 448 controls were analysed using the polymerase chain reaction followed by restriction endonuclease digestion with Msel. ELISA for quantification of ES was performed in serum from 118 SBC woman and 158 controls. Controls' samples were in Hardy-Weinberg equilibrium (X2= 2.15, P= 0.14). In contrast, patients' samples did not confirm the Hardy-Weinberg expectations at the D104N locus (X2= 22.87, P< 0.0001). We observed a higher frequency of 104NN polymorphism in SBC patients than in controls (2.8% vs 0.0%, respectively). Individuals with the 104NN polymorphism had an infinite risk for disease (P= 0.003) when compared with those with other genotypes. The frequencies of the 104NN polymorphism were similar in patients stratified by clinical (age, ethnical origin, ages of menarche, menopause, first full-term pregnancy, lactation, hormone replacement therapy, and smoke habit) and laboratory variables (tumour histology, histological and nuclear grades, status of estrogen and progesterone receptors, and stage TNM of the tumour). The median values of ES was higher in patients than in controls (P< 0.001). Similar median values of ES were seen among patients (P> 0 759) and controls (P= 0.535) stratified by genotypes However, differences in clinical and laboratory manifestation and levels of ES may not have reached statistical significance due to the small number of individuals with the 104N allele, enrolled in study. Our results suggest that the 104NN genotype of the COLI8AI gene is associated with SBC susceptibility, possibly due to an abnormal ES function. (AU)