Medullary thyroid carcinoma identified within the first year of life in children with hereditary multiple endocrine neoplasia type 2A (codon 634) and 2B.
We compared two oncogenic RET mutants, associated with MEN 2A (2ARET) or MEN 2B (2BRET) disease subtypes, that are predicted to have distinct downstream target genes.
Using a proteomic-multiplexed analysis of the phosphotyrosine signaling together with antibody-based validation techniques, we identified several candidate molecules for RET (rearranged during transfection) tyrosine kinase receptor carrying mutations responsible for the multiple endocrine neoplasia type 2A and 2B (MEN2A and MEN2B) syndromes in two human medullary thyroid carcinoma (MTC) cell lines, TT and MZ-CRC-1, which express the RET-MEN2A and RET-MEN2B oncoproteins, respectively.
Histopathologic and clinical features of medullary microcarcinoma and C-cell hyperplasia in prophylactic thyroidectomies for medullary carcinoma: a study of 42 cases.
More than 90% of M918T carriers with multiple endocrine neoplasia type 2B (MEN 2B) harbor de novo mutations in the REarranged during Transfection (RET) protooncogene.
MEN 2B (multiple endocrine neoplasia type 2B) is an autosomal dominant cancer syndrome caused by an oncogenic form of the receptor tyrosine kinase REarranged during transfection (RET).
Although there were no syndromic features or a positive family history, mutation analysis of the RET proto-oncogene showed a de novo germline Met918Thr mutation in both patients, confirming the diagnosis of multiple endocrine neoplasia type 2B (MEN 2B).
In multiple endocrine neoplasia 2B (MEN-2B) patients expressing RET(M918T), nuclear enrichment of STAT3 and elevated expression of CXCR4 was detected in metastatic thyroid C-cell carcinoma in the liver.
There are three subtypes, namely, MEN2A (multiple endocrine neoplasia type 2A), MEN2B (multiple endocrine neoplasia type 2B), and familial medullary thyroid carcinoma.
Molecular genetic studies detected in all 3 patients a mutation at codon 918 of the RET proto-oncogene known to be present in 95% of the cases of MEN type IIb.