Abstract |
Germ-line protein kinase A (PKA) regulatory-subunit type-Ialpha (RIalpha; PRKAR1A)-inactivating mutations and loss-of-heterozygosity (LOH) of its 17q22-24 locus have been found in Cushing syndrome (CS) caused by primary pigmented nodular adrenocortical disease (PPNAD). We examined whether somatic 17q22-24, PRKAR1A, or PKA changes are present in 44 sporadic adrenocortical tumors (29 adenomas and 15 cancers); 26 of these tumors were responsible for CS. A probe containing the PRKAR1A gene-mapped by fluorescent in situ hybridization to 17q22-24-and corresponding microsatellite markers were used to study allelic losses; PRKAR1A was sequenced in all samples. 17q22-24 losses were seen in 23 and 53% of adenomas and cancers, respectively. In three tumors, somatic, PRKAR1A-inactivating mutations were identified: (a) a nonsense mutation in exon 6 (A751G); (b) a splicing mutation (9IVS-1G/A); and (c) a transition (1050T>C) followed by a 22-bp deletion, also in exon 9; all predicted premature RIalpha protein terminations. Quantitative message and protein studies showed RIalpha down-regulation in tumors with genetic changes; their cortisol secretion pattern was similar to that of PPNAD, and they had higher PKA activity by enzymatic studies. We conclude that somatic allelic losses of the 17q22-24 region, PRKAR1A-inactivating mutations or down-regulation, and corresponding PKA activity changes are present in at least some sporadic adrenocortical tumors, especially those with a PPNAD-like clinical presentation of CS.
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Authors | Jerome Bertherat, Lionel Groussin, Fabiano Sandrini, Ludmila Matyakhina, Thalia Bei, Sotirios Stergiopoulos, Theocharis Papageorgiou, Isabelle Bourdeau, Lawrence S Kirschner, Caroline Vincent-Dejean, Karine Perlemoine, Christine Gicquel, Xavier Bertagna, Constantine A Stratakis |
Journal | Cancer research
(Cancer Res)
Vol. 63
Issue 17
Pg. 5308-19
(Sep 01 2003)
ISSN: 0008-5472 [Print] United States |
PMID | 14500362
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Cyclic AMP-Dependent Protein Kinase RIalpha Subunit
- PRKAR1A protein, human
- RNA, Messenger
- Cyclic AMP-Dependent Protein Kinases
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Topics |
- Adrenal Cortex Neoplasms
(enzymology, genetics)
- Adrenocortical Adenoma
(enzymology, genetics)
- Adult
- Aged
- Alleles
- Blotting, Western
- Chromosome Mapping
- Chromosomes, Human, Pair 17
(genetics)
- Cushing Syndrome
(complications, enzymology, genetics)
- Cyclic AMP-Dependent Protein Kinase RIalpha Subunit
- Cyclic AMP-Dependent Protein Kinases
(biosynthesis, genetics, metabolism)
- Female
- Humans
- Immunohistochemistry
- Loss of Heterozygosity
- Male
- Middle Aged
- Mutation
- RNA, Messenger
(biosynthesis, genetics)
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