SUMMARY We describe a comprehensive genomic characterization of adrenocortical carcinoma (ACC). Using this dataset, we expand the catalogue of known ACC driver genes to include PRKAR1A, RPL22, TERF2, CCNE1, and NF1. Genome wide DNA copy number analysis revealed frequent occurrence of massive DNA loss followed by whole genome doubling (WGD) which was associated with aggressive clinical course, suggesting WGD is a hallmark of disease progression. Corroborating this hypothesis were increased TERT expression, decreased telomere length, and activation of cell cycle programs. Integrated subtype analysis identified three ACC subtypes with distinct clinical outcome and molecular alterations which could be captured by a 68 CpG probe DNA methylation signature, proposing a strategy for clinical stratification of patients based on molecular markers.

Dysregulation of the WNT and insulin-like growth factor 2 (IGF2) signaling pathways has been implicated in sporadic and syndromic forms of adrenocortical carcinoma (ACC). Abnormal β-catenin staining and CTNNB1 mutations are reported to be common in both adrenocortical adenoma and ACC, whereas elevated IGF2 expression is associated primarily with ACC. To better understand the contribution of these pathways in the tumorigenesis of ACC, we examined clinicopathological and molecular data and used mouse models. Evaluation of adrenal tumors from 118 adult patients demonstrated an increase in CTNNB1 mutations and abnormal β-catenin accumulation in both adrenocortical adenoma and ACC. In ACC, these features were adversely associated with survival. Mice with stabilized β-catenin exhibited a temporal progression of increased adrenocortical hyperplasia, with subsequent microscopic and macroscopic adenoma formation. Elevated Igf2 expression alone did not cause hyperplasia. With the combination of stabilized β-catenin and elevated Igf2 expression, adrenal glands were larger, displayed earlier onset of hyperplasia, and developed more frequent macroscopic adenomas (as well as one carcinoma). Our results are consistent with a model in which dysregulation of one pathway may result in adrenal hyperplasia, but accumulation of a second or multiple alterations is necessary for tumorigenesis.

IGF-IR overexpression was a biomarker of pediatric adrenocortical carcinomas. Additionally, a selective IGF-IR kinase inhibitor had antitumor effects in adult and pediatric adrenocortical tumor cell lines, suggesting that IGF-IR inhibitors represent a promising therapy for human adrenocortical carcinoma.

Inherited autosomal dominant mutations in the ARMC5 gene are a frequent cause of PMAH. Biallelic inactivation of ARMC5 is consistent with its role as a potential tumor suppressor gene.

ACTH-independent macronodular adrenal hyperplasia (AIMAH) is an uncommon cause of Cushing's syndrome characterized by bilateral nodular adrenocortical hyperfunction in the presence of suppressed ACTH levels. We investigated whether activating mutations in the ACTH receptor (MC2-R) or G(s alpha) (GNAS1) genes might be involved in AIMAH genesis. Five women with Cushing's syndrome due to AIMAH, confirmed by histological studies, and no signs of McCune-Albright syndrome were selected for molecular analysis of these genes. The single exon of the MC2-R gene and exons 8 and 9 of the GNAS1 gene were amplified by PCR in genomic DNA from adrenal nodules and peripheral blood. Direct sequencing revealed only MC2-R wild-type sequences. GNAS1 PCR products at denaturing gradient gel electrophoresis revealed abnormal migration patterns in adrenal tissues of three patients. Automatic sequencing showed two different activating mutations at codon Arg(201) of GNAS1, a substitution by histidine in two cases and by serine in one case. In conclusion, we found two different gsp mutations in three patients with Cushing's syndrome due to AIMAH, and we speculate whether they belong to the spectrum of McCune-Albright syndrome or whether these are the first reported cases of AIMAH due to gsp mutations.

Desmopressin was able to stimulate the pituitary-adrenal axis in patients with Cushing's disease and, like corticotrophin releasing hormone, it may prove useful in the differential diagnosis of Cushing's syndrome.

Progress in the diagnosis and treatment of endocrine diseases has turned pregnancy into a possibility for women with such medical disorders, including Cushing's syndrome (CS). Nevertheless, despite its rarity, pregnancy in patients with CS can be troublesome because of the risk of maternal-fetal complications. Therefore, hypercortisolism, if present, should be surgically or medically controlled in most cases. Moreover, changes in the hypothalamic-pituitary-adrenal axis during normal pregnancy may mislead the diagnosis of CS during this period, because many laboratory assessments suggestive of CS may be present in normal pregnancy, with clinical features mimicking those seen in patients with CS. The aim of the present review is to update the diagnostic approach to this medical condition, mainly for pregnant women without previous diagnosis of CS, and to describe the therapeutic strategies for CS during pregnancy in order to minimize complications for both mother and fetus.

We demonstrated a higher frequency of SF-1 overexpression and gene amplification in pediatric than in adult adrenocortical tumors, suggesting an important role of SF-1 in pediatric adrenocortical tumorigenesis.