PS-R4 Mutations in BRCA2 gene in male breast cancer cases. Aurrekoetxea-Rodríguez I.1,4, Sánchez-Tapia E.M. 1,4, Martín-Gómez T.2, Vidal-Tocino R.2, Cruz- Hernández J.J. 2,4 and González-Sarmiento R 1,3,4. 1
Laboratorio 14, Centro de Investigación del Cáncer (CIC). Universidad de Salamanca, Salamanca,
España; 2 Servicio de Oncología Médica. Hospital Universitario de Salamanca, Salamanca, España; 3 Unidad de Medicina Molecular-Departamento de Medicina. Universidad de Salamanca, Salamanca, España; 4 Instituto de Investigación Biomédica de Salamanca (IBSAL), Salamanca, España.
id00661366@usal.es Male breast cancer is a disease that affects approximately one in 1,000 men. Being such a rare disease in men, there is little clinical evidence, so the therapeutic treatment for these patients is based on the experience we have in female breast cancer. It is known that there are several risk factors that influence the occurrence of disease, such as age (between 5 and 10 years older than women at the time of diagnosis), a sedentary and unhealthy lifestyle, and various genetic factors. The male breast cancer occurs more frequently in men with Klinefelter syndrome, Cowden syndrome and hereditary breast and ovarian cancer syndrome. Main genes associated with hereditary breast and ovarian cancer syndrome are BRCA1 and BRCA2. As male breast cancer is concerned, mutations in BRCA2 are much more frequent than in BRCA1. Various studies have estimated that there are between 4-40 % men with breast cancer who have BRCA2 mutation. The main aim of this research is to analyze the presence of pathogenic mutations in BRCA2 gene in male with breast cancer in the western part of the Spanish Castilla y León community. A total amount of 27 patients differentiated into two groups were selected. The first group was composed of males who were the only case of breast cancer in their family (18 cases). The second one consisted of males with a family history of breast cancer (8 males). Besides, we also studied a single case of a male with bilateral breast cancer. Thus, to carry out the analysis of mutations in these patients, two techniques were mainly used, the analysis of PCR-amplified fragments by CSGE (Conformation Sensitive Gel Electrophoresis) and Sanger sequencing. In the cases where no mutation was found, a further analysis of large genomic rearrangements was performed by using a MLPA (Multiplex Ligation -dependent Probe Amplification) test. Mutations were detected in three out of eight men with a family history of breast cancer. A patient had a mutation in exon 3 of BRCA2 (c. 373 G > T / p. Glu 49 X) and the other two in exon 11 (c. 3036-3039 of ACAA / p. STOP 958). There were no alterations in patients who did not have a family history, or in the case of the male with bilateral breast cancer. In conclusion, as this research demonstrates, mutations in BRCA2 gene only appear in males with breast cancer and a family history. This could indicate that there must be another gene associated with male breast cancer that is yet unknown.
91