However, the prevalence of other tumors of the Li-Fraumeni syndrome (LFS) and Li-Fraumeni-like syndrome (LFL) spectrum, the clinical outcomes and the potential tumor occurrence in relatives carrying this distinct TP53 mutation were not fully investigated.
Notably, this study further reveals a large portion of still unexplained Li-Fraumeni(-like) cases, warranting comprehensive investigation of recently described candidate genes as well as noncoding regions of the TP53 gene in patients with Li-Fraumeni(-like) syndrome lacking TP53 variants in coding regions.
TP53 partial deletions in our cohort represented 25 % (2/8) of the mutations found, a much higher frequency than usually reported, emphasizing the need to search for TP53 rearrangements in patients with LFS/LFL phenotypes.
Targeted, massively parallel DNA sequencing and molecular inversion probe microarray analysis revealed a germline TP53 mutation compatible with Li-Fraumeni-like syndrome, somatic mutations of PIK3CA in the endometrial cancer, and a somatic mutation of GNA11 and JAK3 in the PMM.
She presented with a clinical diagnosis of Li-Fraumeni-like syndrome (LFL), showing papillary thyroid carcinoma and fibrosarcoma of the left flank, and had no TP53 germline mutations.
Germline TP53 mutations predispose to multiple cancers defining Li-Fraumeni/Li-Fraumeni-like syndrome (LFS/LFL), a disease with large individual disparities in cancer profiles and age of onset.
Seventy probands from families fulfilling clinical criteria for either Li-Fraumeni or Li-Fraumeni-like (LFS/LFL) syndromes and negative forTP53 mutations were screened for germline CNVs.
Germline mutations in the TP53 gene are detected in approximately 80% of families that fulfill LFS criteria and in 15% to 25% of families that fulfill criteria for Li-Fraumeni-like syndrome (LFS), a group of related syndromes with broader clinical criteria.
Li-Fraumeni (LFS) and Li-Fraumeni-like (LFL) syndromes are associated to germline TP53 mutations, and are characterized by the development of central nervous system tumors, sarcomas, adrenocortical carcinomas, and other early-onset tumors.
Association of germline or somatic TP53 missense mutation with oncogene amplification in tumors developed in patients with Li-Fraumeni or Li-Fraumeni-like syndrome.
The present study was aimed at searching for germ line mutations of TP53 gene in familial gastric cancer with cluster for Li-Fraumeni syndrome or Li-Fraumeni-like syndrome.
Deleterious mutations of p53 seemed to be responsible for approximately 1% of non-BRCA1/BRCA2 hereditary breast cancer in Chinese population, and our findings suggested that p53 should be included in genetic testing of Chinese non-LFS/non-LFL high-risk breast cancer families.
These results suggest germline p53 mutations to possibly be responsible for a subset of young adult patient with multiple malignant tumors, even those not meeting the clinical criteria for LFS or LFL.
These results suggest that TP53 PIN3 is another polymorphism in the TP53 pathway that may have a modifier effect on germline TP53 mutations and may contribute to the phenotypic diversity of germline TP53 mutations associated with LFS/LFL patients.
Here, we have screened for TP53 mutation 45 Brazilian unrelated individuals with family histories fulfilling the clinical definitions of Li-Fraumeni (LFS) or Li-Fraumeni-like (LFL) syndromes.
A database has been created to collect information on families carrying a germ-line mutation in the TP53 gene and on families affected with Li-Fraumeni syndromes [Li-Fraumeni syndrome (LFS) and Li-Fraumeni-like syndrome (LFL)].
Patients were chosen from cancer families with phenotypes typical for germline mutations of p53 (LFS, LFL), BRCA1 [hereditary breast (ovarian) cancer, HB(O)C] or a complex consistent with both LFL and HB(O)C. Children with leukemia were included in the study as another high risk group (FELIX et al.1992).
Recently CHK2 was functionally linked to the p53 pathway, and mutations in these two genes seem to result in a similar Li-Fraumeni syndrome (LFS) or Li-Fraumeni-like syndrome (LFL) multi-cancer phenotype frequently including breast cancer.
The mean in vitro lifespan of dermal fibroblast strains derived from cancer-affected individuals belonging to families conforming to the classical Li-Fraumeni-syndrome or the Li-Fraumeni-like syndrome (LF strains), but in whom no TP53 mutation has been found, was not significantly different to that of normal strains.
Because seven of our BRCA1 and BRCA2 mutation-negative families fulfilled the criteria of either Li-Fraumeni syndrome (LFS) or Li-Fraumeni-like syndrome (LFL), we decided to screen them for germ-line TP53 mutations in exons 5-8 using a dual-temperature single-strand conformation polymorphism assay (SSCP).