MicroRNA signature of primary pigmented nodular adrenocortical disease: clinical correlations and regulation of Wnt signaling.
MicroRNAs comprise a novel group of gene regulators implicated in the development of different types of cancer; however, their role in primary pigmented nodular adrenocortical disease (PPNAD) has not been investigated. PPNAD is a bilateral adrenal hyperplasia often associated with Carney complex, a multiple neoplasia syndrome; both disorders are caused by protein kinase A (PKA) regulatory subunit type 1A (PRKARIA)-inactivating mutations. We identified a 44-microRNA gene signature of PPNAD after comparing PPNAD with normal adrenal samples. Specifically, 33 microRNAs were up-regulated and 11 down-regulated in PPNAD relative to normal tissues. These results were validated by stem loop real-time PCR analysis. Comparison of microRNA microarray data with clinicopathologic variables revealed a negative correlation (r = -0.9499) between let-7b expression and cortisol levels in patients with PPNAD. Integration of microRNA microarray with serial analysis of gene expression data together with bioinformatic algorithm predictions revealed nine microRNA-gene target pairs with a potential role in adrenal pathogenesis. Using a PPNAD cell line, we showed that miR-449 was up-regulated and identified its direct target, WNT1-inducible signaling pathway protein 2 (WISP2); in addition, pharmacologic inhibition of PKA resulted in the up-regulation of miR-449 leading to the suppression of WISP2. Overall, we investigated, for the first time, the microRNA profile and its clinical significance in PPNAD; these data also suggest that PKA, via microRNA regulation, affects the Wnt signaling pathway, which through expression and clinical studies is suspected to be a primary mediator of PRKAR1A-related tumorigenesis.
Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, USA.
Dimitrios
D
Iliopoulos
Eirini I
EI
Bimpaki
Maria
M
Nesterova
Constantine A
CA
Stratakis
D000303:Adrenal Cortex Diseases / Q000235:genetics* / Q000378:metabolism; D000465:Algorithms; D055511:CCN Intercellular Signaling Proteins; D019295:Computational Biology; D003480:Cushing Syndrome / Q000235:genetics / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D020869:Gene Expression Profiling; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D036341:Intercellular Signaling Peptides and Proteins / Q000096:biosynthesis / Q000235:genetics; D035683:MicroRNAs / Q000037:antagonists & inhibitors / Q000235:genetics*; D010859:Pigmentation Disorders / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D012097:Repressor Proteins; D015398:Signal Transduction; D014157:Transcription Factors / Q000096:biosynthesis / Q000235:genetics; D051155:Wnt1 Protein / Q000378:metabolism*
D055511:CCN Intercellular Signaling Proteins; C413323:CCN5 protein, human; D036341:Intercellular Signaling Peptides and Proteins; D035683:MicroRNAs; D012333:RNA, Messenger; D012097:Repressor Proteins; D014157:Transcription Factors; C495247:WNT1 protein, human; D051155:Wnt1 Protein; C487931:mirnlet7 microRNA, human; D017868:Cyclic AMP-Dependent Protein Kinases; D006854:Hydrocortisone