Abstract
Cushing's disease is caused by corticotroph adenomas of the pituitary. To explore the molecular mechanisms of endocrine autonomy in these tumors, we performed exome sequencing of 10 corticotroph adenomas. We found somatic mutations in the USP8 deubiquitinase gene in 4 of 10 adenomas. The mutations clustered in the 14-3-3 protein binding motif and enhanced the proteolytic cleavage and catalytic activity of USP8. Cleavage of USP8 led to increased deubiqutination of the EGF receptor, impairing its downregulation and sustaining EGF signaling. USP8 mutants enhanced promoter activity of the gene encoding proopiomelanocortin. In summary, our data show that dominant mutations in USP8 cause Cushing's disease via activation of EGF receptor signaling.
Publication types
-
Comparative Study
-
Research Support, Non-U.S. Gov't
MeSH terms
-
14-3-3 Proteins / metabolism
-
ACTH-Secreting Pituitary Adenoma / complications
-
ACTH-Secreting Pituitary Adenoma / genetics*
-
ACTH-Secreting Pituitary Adenoma / metabolism
-
Adenoma / genetics
-
Adrenocorticotropic Hormone / metabolism
-
Amino Acid Sequence
-
Animals
-
COS Cells
-
Chlorocebus aethiops
-
Endopeptidases / genetics*
-
Endopeptidases / physiology
-
Endosomal Sorting Complexes Required for Transport / genetics*
-
Endosomal Sorting Complexes Required for Transport / physiology
-
ErbB Receptors / metabolism
-
Exome / genetics
-
Gene Expression Regulation, Neoplastic
-
Humans
-
Molecular Sequence Data
-
Mutation*
-
Neoplasm Proteins / genetics*
-
Neoplasm Proteins / physiology
-
Pituitary ACTH Hypersecretion / genetics*
-
Pituitary Neoplasms / complications
-
Pituitary Neoplasms / genetics*
-
Pituitary Neoplasms / metabolism
-
Pro-Opiomelanocortin / biosynthesis
-
Pro-Opiomelanocortin / genetics
-
Sequence Alignment
-
Sequence Homology, Amino Acid
-
Ubiquitin Thiolesterase / genetics*
-
Ubiquitin Thiolesterase / physiology
Substances
-
14-3-3 Proteins
-
Endosomal Sorting Complexes Required for Transport
-
Neoplasm Proteins
-
Pro-Opiomelanocortin
-
Adrenocorticotropic Hormone
-
ErbB Receptors
-
Endopeptidases
-
USP8 protein, human
-
Ubiquitin Thiolesterase