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1.
J Immunother Cancer ; 8(1)2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32474412

RESUMO

BACKGROUND: Adrenocortical carcinoma (ACC) is a rare endocrine malignancy. Tumor-related glucocorticoid excess is present in ~60% of patients and associated with particularly poor prognosis. Results of first clinical trials using immune checkpoint inhibitors were heterogeneous. Here we characterize tumor-infiltrating T lymphocytes (TILs) in ACC in association with glucocorticoids as potential explanation for resistance to immunotherapy. METHODS: We performed immunofluorescence analysis to visualize tumor-infiltrating T cells (CD3+), T helper cells (CD3+CD4+), cytotoxic T cells (CD3+CD8+) and regulatory T cells (Tregs; CD3+CD4+FoxP3+) in 146 ACC tissue specimens (107 primary tumors, 16 local recurrences, 23 metastases). Quantitative data of immune cell infiltration were correlated with clinical data (including glucocorticoid excess). RESULTS: 86.3% of ACC specimens showed tumor infiltrating T cells (7.7 cells/high power field (HPF)), including T helper (74.0%, 6.7 cells/HPF), cytotoxic T cells (84.3%, 5.7 cells/HPF) and Tregs (49.3%, 0.8 cells/HPF). The number of TILs was associated with better overall survival (HR for death: 0.47, 95% CI 0.25 to 0.87), which was true for CD4+- and CD8+ subpopulations as well. In localized, non-metastatic ACC, the favorable impact of TILs on overall and recurrence-free survival was manifested even independently of ENSAT (European Network for the Study of Adrenal Tumors) stage, resection status and Ki67 index. T helper cells were negatively correlated with glucocorticoid excess (Phi=-0.290, p=0.009). Patients with glucocorticoid excess and low TILs had a particularly poor overall survival (27 vs. 121 months in patients with TILs without glucocorticoid excess). CONCLUSION: Glucocorticoid excess is associated with T cell depletion and unfavorable prognosis. To reactivate the immune system in ACC by checkpoint inhibitors, an inhibition of adrenal steroidogenesis might be pivotal and should be tested in prospective studies.

2.
J Clin Endocrinol Metab ; 105(8)2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32449514

RESUMO

CONTEXT: Objective response rate to mitotane in advanced adrenocortical carcinoma (ACC) is approximately 20%, and adverse drug effects are frequent. To date, there is no marker established that predicts treatment response. Mitotane has been shown to inhibit sterol-O-acyl transferase 1 (SOAT1), which leads to endoplasmic reticulum stress and cell death in ACC cells. OBJECTIVE: To investigate SOAT1 protein expression as a marker of treatment response to mitotane. PATIENTS: A total of 231 ACC patients treated with single-agent mitotane as adjuvant (n = 158) or advanced disease therapy (n = 73) from 12 ENSAT centers were included. SOAT1 protein expression was determined by immunohistochemistry on formalin-fixed paraffin-embedded specimens. SETTING: Retrospective study at 12 ACC referral centers. MAIN OUTCOME MEASURE: Recurrence-free survival (RFS), progression-free survival (PFS), and disease-specific survival (DSS). RESULTS: Sixty-one of 135 patients (45%) with adjuvant mitotane treatment had recurrences and 45/68 patients (66%) with mitotane treatment for advanced disease had progressive disease. After multivariate adjustment for sex, age, hormone secretion, tumor stage, and Ki67 index, RFS (hazard ratio [HR] = 1.07; 95% confidence interval [CI], 0.61-1.85; P = 0.82), and DSS (HR = 1.30; 95% CI, 0.58-2.93; P = 0.53) in adjuvantly treated ACC patients did not differ significantly between tumors with high and low SOAT1 expression. Similarly, in the advanced stage setting, PFS (HR = 1.34; 95% CI, 0.63-2.84; P = 0.45) and DSS (HR = 0.72; 95% CI, 0.31-1.70; P = 0.45) were comparable and response rates not significantly different. CONCLUSIONS: SOAT1 expression was not correlated with clinical endpoints RFS, PFS, and DSS in ACC patients with mitotane monotherapy. Other factors appear to be relevant for mitotane treatment response and ACC patient survival.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32373071

RESUMO

Adrenocortical carcinomas (ACC) are aggressive tumors with a heterogeneous prognosis and limited therapeutic options for advanced stages. This study aims to identify novel drug targets for a personalized treatment in ACC. RNA was isolated from 40 formalin-fixed paraffin-embedded ACC samples. We evaluated gene expression of 84 known cancer drug targets by reverse transcriptase quantitative real time-PCR and calculated fold change using 5 normal adrenal glands as reference (overexpression by fold change >2.0). The most promising candidate cyclin-dependent kinase 4 (CDK4) was investigated at protein level in 104 ACC samples and tested by in vitro experiments in two ACC cell lines (NCI-H295R and MUC1). The most frequently overexpressed genes were TOP2A (100% of cases, median fold change = 16.5), IGF2 (95%, fold change = 52.9), CDK1 (80%, fold change = 6.7), CDK4 (62%, fold change = 2.6), PLK4 (60%, fold change = 2.8), and PLK1 (52%, fold change = 2.3). CDK4 was chosen for functional validation, as it is actionable by approved CDK4/6-inhibitors (e.g., palbociclib). Nuclear immunostaining of CDK4 significantly correlated with mRNA expression (R = 0.52, P < 0.005). We exposed both NCI-H295R and MUC1 cell lines to palbociclib and found a concentration- and time-dependent reduction of cell viability, which was more pronounced in the NCI-H295R cells in line with higher CDK4 expression. Furthermore, we tested palbociclib in combination with insulin-like growth factor 1/insulin receptor inhibitor linsitinib showing an additive effect. In conclusion, we demonstrate that RNA profiling is useful to discover potential drug targets and that CDK4/6 inhibitors are promising candidates for treatment of selected patients with ACC.

4.
Cell Death Dis ; 11(3): 192, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32184394

RESUMO

Conditions of impaired adrenal function and tissue destruction, such as in Addison's disease, and treatment resistance of adrenocortical carcinoma (ACC) necessitate improved understanding of the pathophysiology of adrenal cell death. Due to relevant oxidative processes in the adrenal cortex, our study investigated the role of ferroptosis, an iron-dependent cell death mechanism and found high adrenocortical expression of glutathione peroxidase 4 (GPX4) and long-chain-fatty-acid CoA ligase 4 (ACSL4) genes, key factors in the initiation of ferroptosis. By applying MALDI mass spectrometry imaging to normal and neoplastic adrenocortical tissue, we detected high abundance of arachidonic and adrenic acid, two long chain polyunsaturated fatty acids which undergo peroxidation during ferroptosis. In three available adrenal cortex cell models (H295R, CU-ACC1 and CU-ACC-2) a high susceptibility to GPX4 inhibition with RSL3 was documented with EC50 values of 5.7 × 10-8, 8.1 × 10-7 and 2.1 × 10-8 M, respectively, while all non-steroidogenic cells were significantly less sensitive. Complete block of GPX4 activity by RSL3 led to ferroptosis which was completely reversed in adrenal cortex cells by inhibition of steroidogenesis with ketoconazole but not by blocking the final step of cortisol synthesis with metyrapone. Mitotane, the only approved drug for ACC did not induce ferroptosis, despite strong induction of lipid peroxidation in ACC cells. Together, this report is the first to demonstrate extraordinary sensitivity of adrenal cortex cells to ferroptosis dependent on their active steroid synthetic pathways. Mitotane does not induce this form of cell death in ACC cells.

5.
Cancers (Basel) ; 11(11)2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31717455

RESUMO

Cushing's disease (CD) is a rare condition caused by adrenocorticotropic hormone (ACTH)-producing adenomas of the pituitary, which lead to hypercortisolism that is associated with high morbidity and mortality. Treatment options in case of persistent or recurrent disease are limited, but new insights into the pathogenesis of CD are raising hope for new therapeutic avenues. Here, we have performed a meta-analysis of the available sequencing data in CD to create a comprehensive picture of CD's genetics. Our analyses clearly indicate that somatic mutations in the deubiquitinases are the key drivers in CD, namely USP8 (36.5%) and USP48 (13.3%). While in USP48 only Met415 is affected by mutations, in USP8 there are 26 different mutations described. However, these different mutations are clustering in the same hotspot region (affecting in 94.5% of cases Ser718 and Pro720). In contrast, pathogenic variants classically associated with tumorigenesis in genes like TP53 and BRAF are also present in CD but with low incidence (12.5% and 7%). Importantly, several of these mutations might have therapeutic potential as there are drugs already investigated in preclinical and clinical setting for other diseases. Furthermore, network and pathway analyses of all somatic mutations in CD suggest a rather unified picture hinting towards converging oncogenic pathways.

6.
Clin Chem ; 65(10): 1276-1286, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31492715

RESUMO

BACKGROUND: Adrenocortical carcinoma (ACC) is a rare tumor with variable prognosis even within the same tumor stage. Cancer-related sex hormones and their sulfated metabolites in body fluids can be used as tumor markers. The role of steroid sulfation in ACC has not yet been studied. MALDI mass spectrometry imaging (MALDI-MSI) is a novel tool for tissue-based chemical phenotyping. METHODS: We performed phenotyping of formalin-fixed, paraffin-embedded tissue samples from 72 ACC by MALDI-MSI at a metabolomics level. RESULTS: Tumoral steroid hormone metabolites-estradiol sulfate [hazard ratio (HR) 0.26; 95% CI, 0.10-0.69; P = 0.005] and estrone 3-sulfate (HR 0.22; 95% CI, 0.07-0.63; P = 0.003)-were significantly associated with prognosis in Kaplan-Meier analyses and after multivariable adjustment for age, tumor stage, and sex (HR 0.29; 95% CI, 0.11-0.79; P = 0.015 and HR 0.30; 95% CI, 0.10-0.91; P = 0.033, respectively). Expression of sulfotransferase SULT2A1 was associated with prognosis to a similar extent and was validated to be a prognostic factor in two published data sets. We discovered the presence of estradiol-17ß 3,17-disulfate (E2S2) in a subset of tumors with particularly poor overall survival. Electron microscopy revealed novel membrane-delimited organelles in only these tumors. By applying cluster analyses of metabolomic data, 3 sulfation-related phenotypes exhibited specific metabolic features unrelated to steroid metabolism. CONCLUSIONS: MALDI-MSI provides novel insights into the pathophysiology of ACC. Steroid hormone sulfation may be used for prognostication and treatment stratification. Sulfation-related metabolic reprogramming may be of relevance also in conditions beyond the rare ACC and can be directly investigated by the use of MALDI-MSI.

7.
Neuro Oncol ; 21(10): 1273-1283, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31222332

RESUMO

BACKGROUND: Medical treatment in Cushing's disease (CD) is limited due to poor understanding of its pathogenesis. Pathogenic variants of ubiquitin specific peptidase 8 (USP8) have been confirmed as causative in around half of corticotroph tumors. We aimed to further characterize the molecular landscape of those CD tumors lacking USP8 mutations in a large cohort of patients. METHODS: Exome sequencing was performed on 18 paired tumor-blood samples with wild-type USP8 status. Candidate gene variants were screened by Sanger sequencing in 175 additional samples. The most frequent variant was characterized by further functional in vitro assays. RESULTS: Recurrent somatic hotspot mutations in another deubiquitinase, USP48, were found in 10.3% of analyzed samples. Several possibly damaging variants were found in TP53 in 6 of 18 samples. USP48 variants were associated with smaller tumors and trended toward higher frequency in female patients. They also changed the structural conformation of USP48 and increased its catalytic activity toward its physiological substrates histone 2A and zinc finger protein Gli1, as well as enhanced the stimulatory effect of corticotropin releasing hormone (CRH) on pro-opiomelanocortin production and adrenocorticotropic hormone secretion. CONCLUSIONS: USP48 pathogenic variants are relatively frequent in USP8 wild-type tumors and enhance CRH-induced hormone production in a manner coherent with sonic hedgehog activation. In addition, TP53 pathogenic variants may be more frequent in larger CD tumors than previously reported.

8.
J Clin Endocrinol Metab ; 104(7): 2535-2546, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30844069

RESUMO

CONTEXT: Cushing disease (CD) is a rare disorder with severe sequels and incompletely understood pathogenesis. The underlying corticotroph adenomas harbor frequently somatic mutations in the ubiquitin-specific peptidase 8 (USP8) gene. These mutations render USP8 hyperactive and prevent client proteins from degradation. OBJECTIVE: To investigate the impact of USP8 mutations on proteins deregulated in CD. DESIGN: One hundred eight pituitary adenomas (75 corticotroph [58 USP8 wild type (WT) and 17 USP8 mutated], 14 somatotroph, and 19 nonfunctioning) were investigated by immunohistochemistry. All evaluated proteins [USP8, arginine vasopressin receptor 1b and 2, corticotropin-releasing hormone receptor, cAMP response element-binding protein (CREB), p27/kip1, cyclin E, heat shock protein 90 (HSP90), orphan nuclear receptor 4, epidermal growth factor receptor, histone deacetylase 2, glucocorticoid receptor, cyclin-dependent kinase 5 and Abelson murine leukemia viral oncogene homolog 1 enzyme substrate 1] were known to be deregulated in CD. Furthermore, AtT20 cells were transfected with USP8 to investigate the expression of possible downstream proteins by immunoblot. RESULTS: Whereas most of the investigated proteins were not differentially expressed, the cell-cycle inhibitor p27 was significantly reduced in USP8 mutated corticotroph adenoma (H-score 2.0 ± 1.0 vs 1.1 ± 1.1 in WT adenomas; P = 0.004). In contrast, the chaperone HSP90 was expressed higher (0.5 ± 0.4 vs 0.2 ± 0.4; P = 0.29), and the phosphorylation of the transcription factor CREB was increased in USP8 mutated adenomas (1.30.5 ± 0.40.9 vs 0.70.5 ± 0.40.7; P = 0.014). Accordingly, AtT20 cells transfected with the USP8 P720R mutant had higher phosphorylated CREB (pCREB) levels than WT transfected cells (1.3 ± 0.14 vs 1 ± 0.23; P = 0.13). CONCLUSIONS: We could demonstrate that USP8 mutations are associated with deregulation of p27/kip1, HSP90, and pCREB. These findings suggest that these proteins are direct or indirect clients of USP8 and could therefore be potential targets for therapeutic approaches in patients with CD.

9.
Endocrinology ; 160(2): 447-459, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30615103

RESUMO

Cushing syndrome is a severe endocrine disorder of cortisol excess associated with major metabolic and cardiovascular sequelae. We recently identified somatic mutations in PRKACA, the gene encoding the catalytic (C) α subunit of protein kinase A (PKA), as being responsible for cortisol-producing adrenocortical adenomas (CPAs), which are a major cause of Cushing syndrome. In spite of previous studies on the two initially identified mutations (L206R, 199_200insW), the mechanisms of action of the clinically highly relevant PRKACA mutations remain poorly understood. Here, by investigating a large panel of PRKACA mutations, including all those identified so far in Cushing syndrome, we unexpectedly found that not all mutations interfere with the binding of regulatory (R) subunits as previously hypothesized. Because several mutations lie in a region of PKA Cα involved in substrate recognition, we investigated their consequences on substrate specificity by quantitative phosphoproteomics. We found that all three mutations analyzed (L206R, 200_201insV, and d244-248+E249Q) cause major changes in the preference of PKA for its targets, leading to hyperphosphorylation of several PKA substrates, most notably including histone H1.4 at Ser36, which is required for and promotes mitosis. This is reflected by a ninefold hyperphosphorylation of H1.4 in CPAs carrying the L206R mutation. Thus, our findings suggest that in addition to hampering binding to R subunits, PRKACA mutations act by altering PKA substrate specificity. These findings shed light on the molecular events leading to Cushing syndrome and illustrate how mutations altering substrate specificity of a protein kinase may cause human disease.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Adenoma Adrenocortical/genética , Síndrome de Cushing/etiologia , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Humanos , Mutação , Fosforilação , Especificidade por Substrato
10.
Minerva Endocrinol ; 44(1): 25-32, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29963826

RESUMO

Somatic mutations affecting genes in the cAMP/PKA (protein kinase A) signaling pathway have been described as causative for the pathogenesis of benign unilateral adrenocortical adenomas associated with cortisol over secretion. These include predominantly somatic mutations in the PRKACA gene which encodes the catalytic subunit α of PKA. In addition, mutations in the GNAS gene, coding for the stimulatory G protein α, have been observed in approximately 10% of cortisol producing adenomas (CPA). The mutations render PKA signaling constitutively active and are therefore involved in cortisol over secretion of these tumors. Despite the prominent role of the cAMP/PKA pathway in the pathogenesis of unilateral CPA, also mutations in the CTNNB1 gene, encoding ß-catenin, were identified in CPA. However, mutations in ß-catenin are not limited to CPA and are not associated with cortisol secretion since they were predominantly found in endocrine-inactive adenomas (EIA) and might hence contribute to tumorigenesis in adrenocortical tissues. In this review, recent findings in the pathogenesis of benign adrenocortical tumors with a particular focus on the cAMP/PKA signaling pathway are summarized.


Assuntos
Neoplasias do Córtex Suprarrenal/metabolismo , Neoplasias do Córtex Suprarrenal/patologia , Adenoma Adrenocortical/metabolismo , Adenoma Adrenocortical/patologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Transdução de Sinais , Humanos
11.
Mol Cell Endocrinol ; 480: 36-41, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30315857

RESUMO

90 kDa heat shock proteins (Hsp90) act as protein chaperones and play a role in modulating endoplasmic reticulum (ER) stress. Hsp90 inhibitors are under clinical investigation as cancer treatment. Mitotane therapy of adrenocortical carcinoma (ACC) has been shown to act through lipid-induced ER-stress. To explore the potential of Hsp90 inhibitors in ACC as a single agent and in combination with mitotane, we analyzed two independent gene expression data sets of adrenal tumors in silico and treated the ACC cell line model NCI-H295 with Hsp90 inhibitors BIIB021 (B) and CCT18159 (C) alone and in combination with mitotane. ER-stress markers were monitored by immunoblotting. Drug synergism was quantified using the median effect model with cell viability as read-out. Cytosolic Hsp90 isoforms AA1 and AB1 were significantly overexpressed in ACC. Viability of H295 cells was impaired by B and C as single agents with an EC50 of 5.7 × 10-6M and 12.1 × 10-6M. B but not C dose-dependently increased XBP1 splicing and CHOP expression indicative of ER-stress activation. ER-stress marker expression was enhanced by co-incubation of B with 10  µM but not 5  µM mitotane. Maximal CHOP expression was induced by 25 µM mitotane alone with no additional effect of B. Combination indices (CI) of B and C with mitotane ranged from 0.64 to 1.38 and 0.68 to 1.30, respectively where CI values < 0.5 support clinically-relevant drug synergism. In conclusion, Hsp90 paralogs are differentially expressed in ACC and B but not C activates ER-stress in ACC cells. No meaningful drug synergism of Hsp90 inhibitors with mitotane was observed.


Assuntos
Carcinoma Adrenocortical/tratamento farmacológico , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Mitotano/uso terapêutico , Adenina/análogos & derivados , Adenina/farmacologia , Adenina/uso terapêutico , Carcinoma Adrenocortical/genética , Carcinoma Adrenocortical/patologia , Linhagem Celular , Simulação por Computador , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Compostos Heterocíclicos com 2 Anéis/farmacologia , Compostos Heterocíclicos com 2 Anéis/uso terapêutico , Humanos , Mitotano/farmacologia , Pirazóis/farmacologia , Pirazóis/uso terapêutico , Piridinas/farmacologia , Piridinas/uso terapêutico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
12.
J Clin Endocrinol Metab ; 103(12): 4511-4523, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30113656

RESUMO

Context: Adrenocortical carcinoma (ACC) has a heterogeneous prognosis, and current medical therapies have limited efficacy in its advanced stages. Genome-wide multiomics studies identified molecular patterns associated with clinical outcome. Objective: Here, we aimed at identifying a molecular signature useful for both personalized prognostic stratification and druggable targets, using methods applicable in clinical routine. Design: In total, 117 tumor samples from 107 patients with ACC were analyzed. Targeted next-generation sequencing of 160 genes and pyrosequencing of 4 genes were applied to formalin-fixed, paraffin-embedded (FFPE) specimens to detect point mutations, copy number alterations, and promoter region methylation. Molecular results were combined with clinical/histopathological parameters (tumor stage, age, symptoms, resection status, and Ki-67) to predict progression-free survival (PFS). Results: In addition to known driver mutations, we detected recurrent alterations in genes not previously associated with ACC (e.g., NOTCH1, CIC, KDM6A, BRCA1, BRCA2). Best prediction of PFS was obtained integrating molecular results (more than one somatic mutation, alterations in Wnt/ß-catenin and p53 pathways, high methylation pattern) and clinical/histopathological parameters into a combined score (P < 0.0001, χ2 = 68.6). Accuracy of prediction for early disease progress was 83.3% (area under the receiver operating characteristic curve: 0.872, 95% confidence interval 0.80 to 0.94). Furthermore, 17 potentially targetable alterations were found in 64 patients (e.g., in CDK4, NOTCH1, NF1, MDM2, and EGFR and in DNA repair system). Conclusions: This study demonstrates that molecular profiling of FFPE tumor samples improves prognostication of ACC beyond clinical/histopathological parameters and identifies new potential drug targets. These findings pave the way to precision medicine in this rare disease.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Carcinoma Adrenocortical/genética , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Medicina de Precisão/métodos , Córtex Suprarrenal/patologia , Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Neoplasias do Córtex Suprarrenal/mortalidade , Neoplasias do Córtex Suprarrenal/patologia , Carcinoma Adrenocortical/tratamento farmacológico , Carcinoma Adrenocortical/mortalidade , Carcinoma Adrenocortical/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacologia , Biomarcadores Tumorais/antagonistas & inibidores , Variações do Número de Cópias de DNA , Metilação de DNA , Análise Mutacional de DNA , Feminino , Seguimentos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Mutação Puntual , Prognóstico , Intervalo Livre de Progressão , Regiões Promotoras Genéticas/genética , Estudos Retrospectivos , Análise de Sobrevida , Adulto Jovem
13.
Sci Rep ; 7(1): 49, 2017 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-28250426

RESUMO

Somatic mutations in protein kinase A catalytic α subunit (PRKACA) were found to be causative for 30-40% of cortisol-producing adenomas (CPA) of the adrenal gland, rendering PKA signalling constitutively active. In its resting state, PKA is a stable and inactive heterotetramer, consisting of two catalytic and two regulatory subunits with the latter inhibiting PKA activity. The human genome encodes three different PKA catalytic subunits and four different regulatory subunits that are preferentially expressed in different organs. In normal adrenal glands all regulatory subunits are expressed, while CPA exhibit reduced protein levels of the regulatory subunit IIß. In this study, we linked for the first time the loss of RIIß protein levels to the PRKACA mutation status and found the down-regulation of RIIß to arise post-transcriptionally. We further found the PKA subunit expression pattern of different tumours is also present in the zones of the normal adrenal cortex and demonstrate that the different PKA subunits have a differential expression pattern in each zone of the normal adrenal gland, indicating potential specific roles of these subunits in the regulation of different hormones secretion.


Assuntos
Glândulas Suprarrenais/fisiologia , Adenoma Adrenocortical/patologia , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/análise , Subunidade RIIbeta da Proteína Quinase Dependente de AMP Cíclico/análise , Perfilação da Expressão Gênica , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/genética , Humanos
14.
Oncotarget ; 8(6): 9323-9338, 2017 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-28030838

RESUMO

Livin/BIRC7 is a member of the inhibitors of apoptosis proteins family, which are involved in tumor development through the inhibition of caspases. Aim was to investigate the expression of livin and other members of its pathway in adrenocortical tumors and in the adrenocortical carcinoma (ACC) cell line NCI-H295R.The mRNA expression of livin, its isoforms α and ß, XIAP, CASP3 and DIABLO was evaluated by qRT-PCR in 82 fresh-frozen adrenal tissues (34 ACC, 25 adenomas = ACA, 23 normal adrenal glands = NAG). Livin protein expression was assessed by immunohistochemistry in 270 paraffin-embedded tissues (192 ACC, 58 ACA, 20 NAG). Livin, CASP3 and cleaved caspase-3 were evaluated in NCI-H295R after induction of livin overexpression.Relative livin mRNA expression was significantly higher in ACC than in ACA and NAG (0.060 ± 0.116 vs 0.004 ± 0.014 and 0.002 ± 0.009, respectively, p < 0.01), being consistently higher in tumors than in adjacent NAG and isoform ß more expressed than α. No significant differences in CASP3, XIAP and DIABLO levels were found among these groups. In immunohistochemistry, livin was localized in both cytoplasm and nuclei. The ratio between cytoplasmic and nuclear staining was significantly higher in ACC (1.51 ± 0.66) than in ACA (0.80 ± 0.35) and NAG (0.88 ± 0.27; p < 0.0001). No significant correlations were observed between livin expression and histopathological parameters or clinical outcome. In NCI-H295R cells, the livin overexpression slightly reduced the activation of CASP3, but did not correlate with cell viability.In conclusion, livin is specifically over-expressed in ACC, suggesting that it might be involved in adrenocortical tumorigenesis and represent a new molecular marker of malignancy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias do Córtex Suprarrenal/metabolismo , Carcinoma Adrenocortical/metabolismo , Biomarcadores Tumorais/metabolismo , Proteínas Inibidoras de Apoptose/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Neoplasias do Córtex Suprarrenal/genética , Neoplasias do Córtex Suprarrenal/patologia , Neoplasias do Córtex Suprarrenal/cirurgia , Carcinoma Adrenocortical/genética , Carcinoma Adrenocortical/patologia , Carcinoma Adrenocortical/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas Reguladoras de Apoptose , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Citosol/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Proteínas Inibidoras de Apoptose/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Proteínas de Neoplasias/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Transfecção , Regulação para Cima , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Adulto Jovem
15.
PLoS One ; 11(12): e0169009, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28005997

RESUMO

PURPOSE: Cushing's disease (CD), also known as pituitary-dependent hyperadrenocorticism, is caused by adrenocorticotropic hormone (ACTH)-secreting pituitary tumours. Affected humans and dogs have similar clinical manifestations, however, the incidence of the canine disease is thousand-fold higher. This makes the dog an obvious model for studying the pathogenesis of pituitary-dependent hyperadrenocorticism. Despite certain similarities identified at the molecular level, the question still remains whether the two species have a shared oncogenetic background. Recently, hotspot recurrent mutations in the gene encoding for ubiquitin specific protease 8 (USP8) have been identified as the main driver behind the formation of ACTH-secreting pituitary adenomas in humans. In this study, we aimed to verify whether USP8 mutations also play a role in the development of such tumours in dogs. METHODS: Presence of USP8 mutations was analysed by Sanger and PCR-cloning sequencing in 38 canine ACTH-secreting adenomas. Furthermore, the role of USP8 and EGFR protein expression was assessed by immunohistochemistry in a subset of 25 adenomas. RESULTS: None of the analysed canine ACTH-secreting adenomas presented mutations in the USP8 gene. In a subset of these adenomas, however, we observed an increased nuclear expression of USP8, a phenotype characteristic for the USP8 mutated human tumours, that correlated with smaller tumour size but elevated ACTH production in those tumours. CONCLUSIONS: Canine ACTH-secreting pituitary adenomas lack mutations in the USP8 gene suggesting a different genetic background of pituitary tumourigenesis in dogs. However, elevated nuclear USP8 protein expression in a subset of tumours was associated with a similar phenotype as in their human counterparts, indicating a possible end-point convergence of the different genetic backgrounds in the two species. In order to establish the dog as a useful animal model for the study of CD, further comprehensive studies are needed.


Assuntos
Adenoma Hipofisário Secretor de ACT/veterinária , Doenças do Cão/genética , Endopeptidases/genética , Mutação , Ubiquitina Tiolesterase/genética , Adenoma Hipofisário Secretor de ACT/genética , Animais , Cães , Feminino , Masculino , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
16.
J Clin Endocrinol Metab ; 101(9): 3526-38, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27389594

RESUMO

CONTEXT: Adrenocortical adenomas (ACAs) are among the most frequent human neoplasias. Genetic alterations affecting the cAMP/protein kinase A signaling pathway are common in cortisol-producing ACAs, whereas activating mutations in the gene encoding ß-catenin (CTNNB1) have been reported in a subset of both benign and malignant adrenocortical tumors. However, the molecular pathogenesis of most ACAs is still largely unclear. OBJECTIVE: The aim of the study was to define the genetic landscape of sporadic unilateral ACAs. DESIGN AND SETTING: Next-generation whole-exome sequencing was performed on fresh-frozen tumor samples and corresponding normal tissue samples. PATIENTS: Ninety-nine patients with ACAs (74 cortisol-producing and 25 endocrine inactive) negative for p.Leu206Arg PRKACA mutation. MAIN OUTCOME MEASURES: Identification of known and/or new genetic alterations potentially involved in adrenocortical tumorigenesis and autonomous hormone secretion, genotype-phenotype correlation. RESULTS: A total of 706 somatic protein-altering mutations were detected in 88 of 99 tumors (median, six per tumor). We identified several mutations in genes of the cAMP/protein kinase A pathway, including three novel mutations in PRKACA, associated with female sex and Cushing's syndrome. We also found genetic alterations in different genes involved in the Wnt/ß-catenin pathway, associated with larger tumors and endocrine inactivity, and notably, in many genes of the Ca(2+)-signaling pathway. Finally, by comparison of our genetic data with those available in the literature, we describe a comprehensive genetic landscape of unilateral ACAs. CONCLUSIONS: This study provides the largest sequencing effort on ACAs to date. We thereby identified somatic alterations affecting known and novel pathways potentially involved in adrenal tumorigenesis.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Adenoma Adrenocortical/genética , Biomarcadores Tumorais/genética , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/genética , Exoma/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Mutação/genética , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade
17.
Eur J Endocrinol ; 174(3): 363-72, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26701869

RESUMO

CONTEXT: Alterations in the cAMP signaling pathway are common in hormonally active endocrine tumors. Somatic mutations at GNAS are causative in 30-40% of GH-secreting adenomas. Recently, mutations affecting the USP8 and PRKACA gene have been reported in ACTH-secreting pituitary adenomas and cortisol-secreting adrenocortical adenomas respectively. However, the pathogenesis of many GH-secreting adenomas remains unclear. AIM: Comprehensive genetic characterization of sporadic GH-secreting adenomas and identification of new driver mutations. DESIGN: Screening for somatic mutations was performed in 67 GH-secreting adenomas by targeted sequencing for GNAS, PRKACA, and USP8 mutations (n=31) and next-generation exome sequencing (n=36). RESULTS: By targeted sequencing, known activating mutations in GNAS were detected in five cases (16.1%), while no somatic mutations were observed in both PRKACA and USP8. Whole-exome sequencing identified 132 protein-altering somatic mutations in 31/36 tumors with a median of three mutations per sample (range: 1-13). The only recurrent mutations have been observed in GNAS (31.4% of cases). However, seven genes involved in cAMP signaling pathway were affected in 14 of 36 samples and eight samples harbored variants in genes involved in the calcium signaling or metabolism. At the enrichment analysis, several altered genes resulted to be associated with developmental processes. No significant correlation between genetic alterations and the clinical data was observed. CONCLUSION: This study provides a comprehensive analysis of somatic mutations in a large series of GH-secreting adenomas. No novel recurrent genetic alterations have been observed, but the data suggest that beside cAMP pathway, calcium signaling might be involved in the pathogenesis of these tumors.


Assuntos
Adenoma/genética , Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/genética , Endopeptidases/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Adenoma Hipofisário Secretor de Hormônio do Crescimento/genética , Ubiquitina Tiolesterase/genética , Adulto , Idoso , Cromograninas , Exoma/genética , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Adulto Jovem
18.
Trends Endocrinol Metab ; 26(10): 573-583, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26412158

RESUMO

Cushing's disease (CD) is caused by corticotropin-secreting pituitary adenomas and results in substantial morbidity and mortality. Its molecular basis has remained poorly understood until the past few years, when several proteins and genes [such as testicular orphan nuclear receptor 4 (TR4) and heat shock protein 90 (HSP90)] were found to play key roles in the disease. Most recently, mutations in the gene of ubiquitin-specific peptidase 8 (USP8) increasing its deubiquination activity were discovered in a high percentage of corticotroph adenomas. Here, we will discuss emerging insights in the molecular alterations that finally result in CD. The therapeutic potential of these findings needs to be carefully evaluated in the near future, hopefully resulting in new treatment options for this devastating disorder.


Assuntos
Hipersecreção Hipofisária de ACTH/metabolismo , Proteínas 14-3-3/metabolismo , Animais , Receptores ErbB/metabolismo , Humanos , Hipersecreção Hipofisária de ACTH/genética
19.
Endocrinology ; 156(11): 3895-908, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26305886

RESUMO

Adrenocortical carcinoma (ACC) is a rare malignancy that harbors a dismal prognosis in advanced stages. Mitotane is approved as an orphan drug for treatment of ACC and counteracts tumor growth and steroid hormone production. Despite serious adverse effects, mitotane has been clinically used for decades. Elucidation of its unknown molecular mechanism of action seems essential to develop better ACC therapies. Here, we set out to identify the molecular target of mitotane and altered downstream mechanisms by combining expression genomics and mass spectrometry technology in the NCI-H295 ACC model cell line. Pathway analyses of expression genomics data demonstrated activation of endoplasmic reticulum (ER) stress and profound alteration of lipid-related genes caused by mitotane treatment. ER stress marker CHOP was strongly induced and the two upstream ER stress signalling events XBP1-mRNA splicing and eukaryotic initiation factor 2 A (eIF2α) phosphorylation were activated by mitotane in NCI-H295 cells but to a much lesser extent in four nonsteroidogenic cell lines. Lipid mass spectrometry revealed mitotane-induced increase of free cholesterol, oxysterols, and fatty acids specifically in NCI-H295 cells as cause of ER stress. We demonstrate that mitotane is an inhibitor of sterol-O-acyl-transferase 1 (SOAT1) leading to accumulation of these toxic lipids. In ACC tissue samples we show variable SOAT1 expression correlating with the response to mitotane treatment. In conclusion, mitotane confers adrenal-specific cytotoxicity and down-regulates steroidogenesis by inhibition of SOAT1 leading to lipid-induced ER stress. Targeting of cancer-specific lipid metabolism opens new avenues for treatment of ACC and potentially other types of cancer.


Assuntos
Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Mitotano/farmacologia , Esterol O-Aciltransferase/antagonistas & inibidores , Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Neoplasias do Córtex Suprarrenal/genética , Neoplasias do Córtex Suprarrenal/metabolismo , Carcinoma Adrenocortical/tratamento farmacológico , Carcinoma Adrenocortical/genética , Carcinoma Adrenocortical/metabolismo , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Intervalo Livre de Doença , Estresse do Retículo Endoplasmático/genética , Cromatografia Gasosa-Espectrometria de Massas , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Immunoblotting , Imuno-Histoquímica , Lipídeos/análise , Mitotano/uso terapêutico , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esterol O-Aciltransferase/genética , Esterol O-Aciltransferase/metabolismo , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo , Transcriptoma/efeitos dos fármacos
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