Mutational analysis revealed in the first patient the APC germline mutation 3183_87del ACAAA and in the second patient the del9-10 (del9080dup11) novel APC variant; the first mutation has been already reported in association with PTC; to our knowledge the second mutation has never been previously reported in association with FAP.
We report on bidirectional sequencing of the mutation cluster region (codons 1032-1565) of the APC gene in individually laser-microdissected components of a previously unreported C-MV of PTC.
Western blot analysis demonstrated high levels of cyclin D1 and beta-catenin as well as Pin1 expression in a human PTC cell line possessing wild-type beta-catenin and APC genes.
These findings support a relationship between the morphologic pattern of the C-MV of PTC and the APC gene and the existence of this variant as a sporadic counterpart of familial adenomatous polyposis-associated thyroid carcinoma.
A review of the literature added 11 other patients with FAP-associated PTC and detection of germline APC mutations; they were at codons 313 (n = 2), 698 (n = 3), 848 (n = 2), 1209 (n = 2), 1061 (n = 1), and 1105 (n = 1), respectively.
Familial adenomatous polyposis (FAP) is caused by germ-line mutations of the apc gene, and it is associated with an increased risk of developing papillary thyroid carcinomas.
Germ-line mutations of the adenomatous polyposis (APC) gene, responsible for familial adenomatous polyposis (FAP) were analyzed in 15 patients with FAP-associated papillary thyroid carcinomas: 13 had the mutation between codons 778 and 1309 (exon 15), 1 at codon 593 (exon 14), and 1 at codon 140 (exon 3).