Evaluation of the presence and frequency of the TP53-p.R337H mutation in gastric cancer of patients at Barretos Cancer Hospital

Abstract

Gastric cancer is a very aggressive pathology that still with a frightening prognosis. Despite the decrease of the incidence, the gastric cancer remains as one of the most deadly diseases, being the fourth most diagnosed cancer and the second most deadly cancer in the world. Somatic mutation in the TP53 gene are frequently in gastric tumors. However, the frequency of germline mutations of TP53 gene in these tumors are still unknown, despite several evidences that there is increased frequency of gastric tumors in families with Li-Fraumeni Syndrome. In Brazil, the frequency of germline mutations in TP53 gene is increased compared to the rest of the world, mainly due to the presence of the founding mutation p.Arg337His. Studies conducted in the South of Brazil (Paraná and Rio Grande do Sul), showed a prevalence of 0.3% of this mutation in the general population. Thus, the present studies intends to retrospectively evaluate the presence and the frequency of the p.R337H mutation in the TP53 gene in a group of 518 patients seen at Barretos Cancer Hospital. We also intend to correlate the molecular profile with the histopathological, clinical and prognostic characteristics of the analyzed patients. Clinical and survival information will be obtained from the medical records. The analysis of the presence of the p.R337H will be done by the PCR-RFLP. Positive results will be confirmed by bidirectional sequencing (Sanger). We hope that this work will be the first step towards a better characterization and consequently a greater knowledge about the population with a diagnosis of gastric cancer attended at the Barretos Cancer Hospital as well as to give us more information about the real prevalence of this founding mutation for those patients who are affected by gastric cancer. (AU)