Adrenocortical carcinoma (ACC) is a rare tumour disease with sinister prognosis also after attempts to radical surgery; better prognosis is seen for low-stage tumours. Adjuvant treatment with the adrenolytic drug mitotane has been attempted, but not proven to prevent from recurrence. The drug may offer survival advantage in case of recurrence. The aim of this single-centre study (1979–2007) of 43 consecutive patients was to evaluate the long-term survival after active surgical treatment combined with monitored mitotane (to reduce side effects of the drug). The series is unique, since all patients were offered a period of mitotane as adjuvant or palliative treatment; six patients refused mitotane. Despite a high proportion of high-stage tumours (67%), the complete resection rate was high (77%). The disease-specific 5-year survival was high (64.1%); very high for patients with low-stage tumours without evident relation to mitotane levels. Patients with high-stage tumours had a clear survival advantage with mitotane levels above a threshold of 14 mg/l in serum. The hazard ratio for patients with high mitotane levels versus all patients indicates a significant effect of the drug. The results indicate that adjuvant mitotane may be the standard of care for patients with high-stage ACC after complete resection.
B Wängberg, A Khorram-Manesh, S Jansson, B Nilsson, O Nilsson, C E Jakobsson, S Lindstedt, A Odén, and H Ahlman
Cristina L Ronchi, Silviu Sbiera, Barbara Altieri, Sonja Steinhauer, Vanessa Wild, Michaela Bekteshi, Matthias Kroiss, Martin Fassnacht, and Bruno Allolio
Previous SNP array analyses have revealed genomic alterations of the Notch pathway as being the most frequent abnormality in adrenocortical tumors (ACTs). The aim of the present study was to evaluate the expression of components of Notch signaling in ACTs and to correlate them with clinical outcome. The mRNA expression of JAG1, NOTCH1, and selected target genes of NOTCH1 (HES1, HES5, and HEY2) was evaluated in 80 fresh frozen samples (28 normal adrenal glands (NAGs), 24 adenomas (ACAs), and 28 carcinomas (ACCs)) by quantitative RT-PCR. Immunohistochemistry was performed in 221 tissues on paraffin slides (16 NAGs, 27 ACAs, and 178 ACCs) for JAG1, activated NOTCH1 (aNOTCH1), and HEY2. An independent ACC validation cohort (n=77) was then also investigated. HEY2 mRNA expression was higher in ACCs than it was in ACAs (P<0.05). The protein expression of all of the factors was high (H-score 2–3) in a larger proportion of ACCs as compared to ACAs and NAGs (JAG1 in 27, 15, and 10%; aNOTCH1 in 13, 8, and 0%; HEY2 in 66, 61, and 33% respectively, all P<0.001). High JAG1 expression was associated with earlier tumor stages and lower numbers of metastases in ACCs (both P=0.08) and favorably impacted overall and progression-free survival (PFS) (131 vs 30 months, hazard ratio (HR) 0.45, and 37 vs 9 months, HR 0.51, both P<0.005). This impact on overall survival (OS) was confirmed in the validation cohort. No such association was observed for aNOTCH1 or HEY2. In conclusion, different components of the Notch1 signaling pathway are overexpressed in ACCs, which suggests a role for the pathway in malignant transformation. However, JAG1 is overexpressed in a subgroup of ACCs with a better clinical outcome.
P S H Soon, A J Gill, D E Benn, A Clarkson, B G Robinson, K L McDonald, and S B Sidhu
The management of adrenocortical tumors (ACTs) is complex. The Weiss score is the present most widely used system for ACT diagnosis. An ACT is scored from 0 to 9, with a higher score correlating with increased malignancy. However, ACTs with a score of 3 can be phenotypically benign or malignant. Our objective is to use microarray profiling of a cohort of adrenocortical carcinomas (ACCs) and adrenocortical adenomas (ACAs) to identify discriminatory genes that could be used as an adjunct to the Weiss score. A cohort of Weiss score defined ACCs and ACAs were profiled using Affymetrix HGU133plus2.0 genechips. Genes with high-discriminatory power were identified by univariate and multivariate analyses and confirmed by quantitative real-time reverse transcription PCR and immunohistochemistry (IHC). The expression of IGF2, MAD2L1, and CCNB1 were significantly higher in ACCs compared with ACAs while ABLIM1, NAV3, SEPT4, and RPRM were significantly lower. Several proteins, including IGF2, MAD2L1, CCNB1, and Ki-67 had high-diagnostic accuracy in differentiating ACCs from ACAs. The best results, however, were obtained with a combination of IGF2 and Ki-67, with 96% sensitivity and 100% specificity in diagnosing ACCs. Microarray gene expression profiling accurately differentiates ACCs from ACAs. The combination of IGF2 and Ki-67 IHC is also highly accurate in distinguishing between the two groups and is particularly helpful in ACTs with Weiss score of 3.
Deniz M Özata, Stefano Caramuta, David Velázquez-Fernández, Pinar Akçakaya, Hong Xie, Anders Höög, Jan Zedenius, Martin Bäckdahl, Catharina Larsson, and Weng-Onn Lui
Adrenocortical carcinoma (ACC) is an aggressive tumor showing frequent metastatic spread and poor survival. Although recent genome-wide studies of ACC have contributed to our understanding of the disease, major challenges remain for both diagnostic and prognostic assessments. The aim of this study was to identify specific microRNAs (miRNAs) associated with malignancy and survival of ACC patients. miRNA expression profiles were determined in a series of ACC, adenoma, and normal cortices using microarray. A subset of miRNAs showed distinct expression patterns in the ACC compared with adrenal cortices and adenomas. Among others, miR-483-3p, miR-483-5p, miR-210, and miR-21 were found overexpressed, while miR-195, miR-497, and miR-1974 were underexpressed in ACC. Inhibition of miR-483-3p or miR-483-5p and overexpression of miR-195 or miR-497 reduced cell proliferation in human NCI-H295R ACC cells. In addition, downregulation of miR-483-3p, but not miR-483-5p, and increased expression of miR-195 or miR-497 led to significant induction of cell death. Protein expression of p53 upregulated modulator of apoptosis (PUMA), a potential target of miR-483-3p, was significantly decreased in ACC, and inversely correlated with miR-483-3p expression. In addition, high expression of miR-503, miR-1202, and miR-1275 were found significantly associated with shorter overall survival among patients with ACC (P values: 0.006, 0.005, and 0.042 respectively). In summary, we identified additional miRNAs associated with ACC, elucidated the functional role of four miRNAs in the pathogenesis of ACC cells, demonstrated the potential involvement of the pro-apoptotic factor PUMA (a miR-483-3p target) in adrenocortical tumors, and found novel miRNAs associated with survival in ACC.
Peter M van Koetsveld, Giovanni Vitale, Richard A Feelders, Marlijn Waaijers, Diana M Sprij-Mooij, Ronald R de Krijger, Ernst-Jan M Speel, Johannes Hofland, Steven W J Lamberts, Wouter W de Herder, and Leo J Hofland
Adrenocortical carcinoma (ACC) is an aggressive tumor with very poor prognosis. Novel medical treatment opportunities are required. We investigated the effects of interferon-β (IFN-β), alone or in combination with mitotane, on cell growth and cortisol secretion in primary cultures of 13 human ACCs, three adrenal hyperplasias, three adrenal adenomas, and in two ACC cell lines. Moreover, the interrelationship between the effects of IGF2 and IFN-β was evaluated. Mitotane inhibited cell total DNA content/well (representing cell number) in 7/11 (IC50: 38±9.2 μM) and cortisol secretion in 5/5 ACC cultures (IC50: 4.5±0.1 μM). IFN-β reduced cell number in 10/11 (IC50: 83±18 IU/ml) and cortisol secretion in 5/5 ACC cultures (IC50: 7.3±1.5 IU/ml). The effect of IFN-β on cell number included the induction of apoptosis. IFN-β strongly inhibited mRNA expression of STAR, CYP11A1, CYP17A1, and CYP11B1. Mitotane and IFN-β induced an additive inhibitory effect on cell number and cortisol secretion. IGF2 (10 nM) inhibited apoptosis and increased cell number and cortisol secretion. These effects were counteracted by IFN-β treatment. Finally, IFN-β inhibited IGF2 secretion and mRNA expression. In conclusion, IFN-β is a potent inhibitor of ACC cell growth in human primary ACC cultures, partially mediated by an inhibition of the effects of IGF2, as well as its production. The increased sensitivity of ACC cells to mitotane induced by treatment with IFN-β may open the opportunity for combined treatment regimens with lower mitotane doses. The inhibition of the expression of steroidogenic enzymes by IFN-β is a novel mechanism that may explain its inhibitory effect on cortisol production.
Kiran Nadella, Fabio R Faucz, and Constantine A Stratakis
Protein kinase A (PKA) regulatory subunit type 1A (PRKAR1A) defects lead to primary pigmented nodular adrenocortical disease (PPNAD). The KIT protooncogene (c-KIT) is not known to be expressed in the normal adrenal cortex (AC). In this study, we investigated the expression of c-KIT and its ligand, stem cell factor (SCF), in PPNAD and other cortisol-producing tumors of the adrenal cortex. mRNA and protein expression, by qRT-PCR, immunohistochemistry (IHC) and immunoblotting (IB), respectively, were studied. We then tested c-KIT and SCF responses to PRKAR1A introduction and PKA stimulation in adrenocortical cell lines CAR47 and H295R, which were also treated with the KIT inhibitor, imatinib mesylate (IM). Mice xenografted with H295R cells were treated with IM. There was increased c-KIT mRNA expression in PPNAD; IHC showed KIT and SCF immunoreactivity within certain nodular areas in PPNAD. IB data was consistent with IHC and mRNA data. PRKAR1A-deficient CAR47 cells expressed c-KIT; this was enhanced by forskolin and lowered by PRKAR1A reintroduction. Knockdown of PKA’s catalytic subunit (PRKACA) by siRNA reduced c-KIT levels. Treatment of the CAR47 cells with IM resulted in reduced cell viability, growth arrest, and apoptosis. Treatment with IM of mice xenografted with H295 cells inhibited further tumor growth. We conclude that c-KIT is expressed in PPNAD, an expression that appears to be dependent on PRKAR1A and/or PKA activity. In a human adrenocortical cell line and its xenografts in mice, c-KIT inhibition decreased growth, suggesting that c-KIT inhibitors may be a reasonable alternative therapy to be tested in PPNAD, when other treatments are not optimal.