Germline mutations in PTEN, that encodes a dual-specificity phosphatase, have been implicated in two hamartoma-tumor syndromes that exhibit some clinical overlap, Cowden syndrome and Bannayan-Zonana syndrome.
Thus, mutations in PTEN are associated with JPS in addition to CD and some BRRS families, although the incidence of PTEN germ-line mutations in JPS might be more rare than that reported for SMAD4, a gene found to be mutated in approximately one-half of the JPS families investigated.
Germline mutations in PTEN, which encode a dual-specificity phosphatase, have been implicated in at least two hamartoma tumor syndromes that exhibit some clinical overlap, Cowden syndrome and Bannayan-Riley-Ruvalcaba syndrome.
Thus, germline BMPR1A mutations cause a significant proportion of cases of JPS and might define a small subset of cases of CS/BRRS with specific colonic phenotype.
Genital lentigines in a 6-year-old boy with a family history of Cowden's disease: clinical and genetic evidence of the linkage between Bannayan-Riley-Ruvacalba syndrome and Cowden's disease.
While germline mutations at this chromosome 10q22-23 locus have been observed in patients with Cowden syndrome (CS) and Bannayan-Riley-Ruvalcaba syndrome (BRR), both of which phenotypes are associated with hamartomata and neoplasia, somatic mutation of PTEN has been established in a wide variety of sporadically occurring neoplasia.
While germline mutations at this chromosome 10q22-23 locus have been observed in patients with Cowden syndrome (CS) and Bannayan-Riley-Ruvalcaba syndrome (BRR), both of which phenotypes are associated with hamartomata and neoplasia, somatic mutation of PTEN has been established in a wide variety of sporadically occurring neoplasia.
Germline PTEN mutations cause Cowden syndrome (CS) and Bannayan-Riley-Ruvalcaba syndrome (BRR), two hamartoma-tumor syndromes with an increased risk of breast, thyroid and endometrial cancers.
This study suggests that PTEN does not play a major role in predisposing to hereditary breast cancer in Israeli women, and that detection of PTEN mutations in BRRS patients is more likely in familial cases.
PTEN is a tumor suppressor gene mutated in many human sporadic cancers and in hereditary cancer syndromes such as Cowden disease, Bannayan-Zonana syndrome and Lhermitte-Duclos disease.
Using real time and multiplex PCR techniques, we identified three germline hemizygous PTEN deletions in 122 apparently mutation-negative patients with classic CS (N=95) or BRRS (N=27).
Pooled analysis of PTEN mutation series of CS and BRRS occurring in the last five years reveals that 65% of CS-associated mutations occur in the first five exons encoding the phosphatase domain and the promoter region, while 60% of BRRS-associated mutations occur in the 3' four exons encoding mainly the C2 domain.
Furthermore, we review the PTEN mutation positive BRRS cases, to further delineate the phenotype and to compare the cases with a genomic deletion with the cases with a point mutation.
Furthermore, we review the PTEN mutation positive BRRS cases, to further delineate the phenotype and to compare the cases with a genomic deletion with the cases with a point mutation.
Cowden's disease (CD) and Bannayan-Ruvalcaba-Riley syndrome (BRRS) are allelic disorders characterized by multiple hamartomatous overgrowths of the thyroid, breast, skin, and gastrointestinal tract, and an increased risk of developing benign and malignant tumors of the breast and thyroid gland, secondary to germline point mutations in the PTEN gene.
Moreover, germline mutation of PTEN leads to the development of the related hereditary cancer predisposition syndromes, Cowden disease, and Bannayan-Zonana syndrome, wherein breast and thyroid cancer incidence is elevated.
As PTEN is a dual phosphatase mutated in autosomal inherited disorders with phenotypes similar to those of PJS (Bannayan-Riley-Ruvalcaba syndrome and Cowden disease), our study suggests a functional link between the proteins involved in different hamartomatous polyposis syndromes and emphasizes the central role played by LKB1 as a tumor suppressor in the small intestine.
As PTEN is a dual phosphatase mutated in autosomal inherited disorders with phenotypes similar to those of PJS (Bannayan-Riley-Ruvalcaba syndrome and Cowden disease), our study suggests a functional link between the proteins involved in different hamartomatous polyposis syndromes and emphasizes the central role played by LKB1 as a tumor suppressor in the small intestine.
PTEN, encoding a dual phosphatase tumor suppressor, is mutated in 85 and 65% of individuals with Cowden syndrome (CS) and Bannayan-Riley-Ruvalcaba syndrome (BRRS), respectively.