R337H mutation of the TP53 gene as a clinical marker in cancer patients: a systematic review of literature.

The germline R337H mutation of the TP53 gene has been associated with the development of many tumor types. This systematic review of literature investigated the association between the R337H mutation and the patients' family history and its predictive and prognostic value in cancer. Data were collected from articles archived in the PubMed, LILACS, MEDLINE, IBECS, and SciELO databases. The systematic review of literature was performed on 12 selected articles, describing a total of 175,462 individuals tested for the R337H mutation, including 1548 individuals with cancer and 118 individuals with a family history of Li-Fraumeni and Li-Fraumeni-like syndrome. Eight studies showed an association between the mutation and a family history of cancer in 411 patients, including 390 cases of cancer among family members. Patients with the homozygous mutant genotype experienced cancer recurrence, progressive disease, secondary cancer, and a short survival rate. Heterozygous patients showed a better response to treatment and increased survival rates than did patients with the homozygous mutant genotype from newborns to adult patients. In conclusion, the R337H mutation has significant predictive and prognostic value and is associated with tumorigenesis of the adrenal cortex.

Analysis of the BRAF V600E mutation in primary cutaneous melanoma.

BRAF V600E is the most common mutation in cutaneous melanomas, and has been described in 30-72% of such cases. This mutation results in the substitution of valine for glutamic acid at position 600 of the BRAF protein, which consequently becomes constitutively activated. The present study investigated the BRAF V600E mutation frequency and its clinical implications in a group of 77 primary cutaneous melanoma patients treated in a cancer reference center in Brazil. Mutation analysis was accomplished by polymerase chain reaction, restriction fragment length polymorphism, and automated DNA sequencing. The chi-squared and Fischer exact tests were used for comparative analyses. The BRAF V600E mutation was detected in 54/77 (70.1%) melanoma subjects. However, no statistically significant association was found between the presence of the mutation and clinical or prognostic parameters. Our results demonstrated that the BRAF V600E mutation is a common event in melanomas, representing an important molecular target for novel therapeutic approaches in such tumors.