Patients with bilateral phaeochromocytomas most often have multiple endocrine neoplasia type 2 (MEN2) or von Hippel-Lindau disease (VHL) with high-penetrance mutations for benign disease, whereas patients with mutations in the genes encoding SDHB (succinate dehydrogenase subunit B) or MAX (myelocytomatosis viral proto-oncogene homologue-associated factor X) are at increased risk of malignancy.
Adrenal-sparing surgery should be the standard approach for patients who have already been diagnosed with MEN2 or VHL when operating on the first side, whereas complete removal of the affected adrenal gland(s) is generally recommended for patients with SDHB or MAX germline mutations.
Hormonal therapy is limited to patients with tumors expressing steroid hormone receptors, such as estrogen receptor (ER), nevertheless resistance often limits its success.The RET gene is known to be involved in neurocristopathies such as Hirschsprung disease and Multiple Endocrine Neoplasia type 2, in the presence of loss-of-function and gain-of-function mutations, respectively.
Significantly higher expression of miR-885-5p and miR-1225-3p was found in multiple endocrine neoplasia type 2 and sporadic recurring pheochromocytomas, respectively.
Significantly higher expression of miR-885-5p and miR-1225-3p was found in multiple endocrine neoplasia type 2 and sporadic recurring pheochromocytomas, respectively.
In addition, the genes responsible for inherited breast and/or ovarian cancer, breast cancer genes 1 and 2 (BRCA1 and BRCA2), and the rearranged during transfection protooncogene RET which is responsible for multiple endocrine neoplasia type 2 are discussed.
In addition, the genes responsible for inherited breast and/or ovarian cancer, breast cancer genes 1 and 2 (BRCA1 and BRCA2), and the rearranged during transfection protooncogene RET which is responsible for multiple endocrine neoplasia type 2 are discussed.
The rate constant for baseline catecholamine secretion was 20-fold higher in VHL than in MEN 2 tumors (0.359 +/- 0.094 vs. 0.018 +/- 0.009 day(-1)), but catecholamine release was responsive only to glucagon in MEN 2 tumors.
NPY levels in phaeochromocytomas from VHL patients were lower (P<0.0001) than in those from MEN 2 patients for both mRNA (84-fold difference) and the peptide (99-fold difference).
Alternatively the differences in expression in CGA and other secretory constituents may reflect downregulation of the entire regulated secretory pathway in VHL compared to MEN 2 tumours.
CGA has several functions, some of which may be involved in the distinct phenotypic differences of phaeochromocytomas in patients with von Hippel-Lindau (VHL) syndrome compared to multiple endocrine neoplasia type 2 (MEN 2).
Quantitative polymerase chain reaction (PCR) and Western blotting were used to assess levels of mRNA and protein for the glucocorticoid receptor, early growth response 1 (Egr-1), the Sp1 transcription factor (Sp1), and MYC-associated zinc finger protein (MAZ) in 6 MEN-2 and 13 VHL tumors.
Pheochromocytomas in MEN-2 and VHL syndrome did not differ in expression of the glucocorticoid receptor, Egr-1, Sp1, or MAZ as assessed by quantitative PCR and Western blotting.
In this report, we investigated the methylation status of the p16INK4a cell cycle inhibitor gene and other prominent tumor-related genes ( PTEN, RASSF1 A, CDH1, MSH2, MLH1, VHL, and TIMP3) in sporadic and multiple endocrine neoplasia type 2 (MEN2) pheochromocytomas by methylation-specific PCR.
Differential expression of erythropoietin and its receptor in von hippel-lindau-associated and multiple endocrine neoplasia type 2-associated pheochromocytomas.