Mutations in the PTEN gene are associated with a broad spectrum of disorders, including Cowden syndrome (CS), Bannayan-Riley-Ruvalcaba syndrome, Proteus syndrome, and Lhermitte-Duclos disease.
Our data suggest that PTEN modulates PLC:PLD activation pathways and indicate that the pathogenesis of CS/BRRS has a more complex biochemical basis beyond simply activating the PI3K pathway.
Cowden syndrome and Bannayan Riley Ruvalcaba syndrome represent one condition with variable expression and age-related penetrance: results of a clinical study of PTEN mutation carriers.
Cowden syndrome and Bannayan Riley Ruvalcaba syndrome represent one condition with variable expression and age-related penetrance: results of a clinical study of PTEN mutation carriers.
Approximately, 10% of CS-related PTEN mutations occur in the PTEN promoter and 11% of BRRS-related mutations include large deletions, often favoring the gene's 5' end (exon 1, promoter).
We show that cell lines from Cowden syndrome and Bannayan-Riley-Ruvalcaba syndrome patients with germ line PTEN promoter mutations in the vicinity of the p53-binding motifs have altered p53 regulation.
We therefore sought to characterize the relative expression of 5', middle, and 3' full-length PTEN mRNA (FL-PTEN) and also of these eight PTEN SVs in 85 (65 female and 20 male) patients with CS/BRRS (with or without PTEN mutations) compared with 27 controls, using a SYBR green quantitative polymerase chain reaction method.
PTEN somatic mutations occur in sporadic tumors of the endometrium, brain, prostate, or melanomas, while germline mutations predispose to development of the multiple hamartoma syndromes (i.e., Cowden's disease and Bannayan-Zonana syndrome).
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.
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.
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.
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.
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).
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.
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.
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.
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.
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.
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.