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Effects of Ketoconazole on ACTH-Producing and Non-ACTH-Producing Neuroendocrine Tumor Cells

Herrera-Martínez, Aura D; Feelders, Richard A; de Herder, Wouter W; Castaño, Justo P; Gálvez Moreno, María Ángeles; Dogan, Fadime; van Dungen, Rosanna; van Koetsveld, Peter; Hofland, Leo J
Prolonged remission of hypercortisolism with steroidogenesis inhibitors has been described in patients with ectopic adrenocorticotropic hormone (ACTH) syndrome. The anti-proliferative and pro-apoptotic effect of ketoconazole in human cancer cells was previously suggested. The aim of this study was to explore the effects of ketoconazole on ACTH-producing and non-ACTH-producing neuroendocrine tumor (NET) cell lines. The effects of ketoconazole alone, and in combination with somatostatin analogs, were evaluated in two human cell lines: DMS-79 (ectopic ACTH-producing small cell lung carcinoma) and BON-1 (human pancreatic NET). Total DNA measurement, apoptosis, cell cycle, chromogranin A (CgA)/proopiomelanocortin (POMC) expression by qRT-PCR, serotonin, CgA, and ACTH secretion assays were performed. In both cell lines, ketoconazole significantly suppressed cell growth and colony formation in a dose and time-dependent manner. The effect in DMS-79 was primarily cytotoxic, while it was more apoptotic in BON-1 cells. Ketoconazole also induced increase in G0/G1 phase in both cell lines and arrest in phase G2/M of BON-1 cells. Ketoconazole did not affect the secretion of serotonin, CgA, ACTH, or the mRNA expression of CgA and POMC. Decreased serotonin secretion was observed after the combination treatment with pasireotide. These results suggest a direct effect of ketoconazole on cell proliferation, apoptosis, and cell cycle in both ACTH- and non-ACTH-producing NET cells.
PMID: 31102172
ISSN: 1868-8500
CID: 4003532

The Effect of Perioperative Music on the Stress Response to Surgery: A Meta-analysis

Fu, Victor X; Oomens, Pim; Sneiders, Dimitri; van den Berg, Sjoerd A A; Feelders, Richard A; Wijnhoven, Bas P L; Jeekel, Johannes
BACKGROUND:Current perioperative patient care aims to maintain homeostasis by attenuation of the stress response to surgery, as a more vigorous stress response can have detrimental effects on postoperative recovery. This systematic review and meta-analysis aims to assess the effect of perioperative music on the physiological stress response to surgery. METHODS:The Embase, Medline Ovid, Cochrane Central, Web of Science, and Google Scholar databases were searched from inception date until February 5, 2019, using a systematic literature search following the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines for randomized controlled trials investigating the effect of music before, during, and/or after surgery in adult surgical patients on the stress response to surgery. Meta-analysis was performed using a random effects model and pooled standardized mean differences were calculated with 95% confidence intervals. This study was registered in the PROSPERO database (CRD42018097060). RESULTS: = 0). CONCLUSIONS:Perioperative music can attenuate the neuroendocrine stress response to surgery.
PMID: 31326711
ISSN: 1095-8673
CID: 4003562

Targeted Systemic Treatment of Neuroendocrine Tumors: Current Options and Future Perspectives

Herrera-Martínez, Aura D; Hofland, Johannes; Hofland, Leo J; Brabander, Tessa; Eskens, Ferry A L M; Gálvez Moreno, María A; Luque, Raúl M; Castaño, Justo P; de Herder, Wouter W; Feelders, Richard A
Neuroendocrine tumors (NETs) originate from the neuroendocrine cell system in the bronchial and gastrointestinal tract and can produce hormones leading to distinct clinical syndromes. Systemic treatment of patients with unresectable NETs aims to control symptoms related to hormonal overproduction and tumor growth. In the last decades prognosis has improved as a result of increased detection of early stage disease and the introduction of somatostatin analogs (SSAs) as well as several new therapeutic options. SSAs are the first-line medical treatment of NETs and can control hormonal production and tumor growth. The development of next-generation multireceptor targeted and radiolabelled somatostatin analogs, as well as target-directed therapies (as second-line treatment options) further improve progression-free survival in NET patients. To date, however, a significant prolongation of overall survival with systemic treatment in NET has not been convincingly demonstrated. Several new medical options and treatment combinations will become available in the upcoming years, and although preliminary results of preclinical and clinical trials are encouraging, large, preferrably randomized clinical studies are required to provide definitive evidence of their effect on survival and symptom control.
PMCID:6338796
PMID: 30560479
ISSN: 1179-1950
CID: 4003432

Advances in the medical treatment of Cushing's syndrome

Feelders, Richard A; Newell-Price, John; Pivonello, Rosario; Nieman, Lynnette K; Hofland, Leo J; Lacroix, Andre
Cushing's syndrome is associated with multisystem morbidity and, when suboptimally treated, increased mortality. Medical therapy is an option for patients if surgery is not successful and can be classified into pituitary-directed drugs, steroid synthesis inhibitors, and glucocorticoid receptor antagonists. In the last decade there have been new developments in each drug category. Targeting dopamine and somatostatin receptors on corticotroph adenomas with cabergoline or pasireotide, or both, controls cortisol production in up to 40% of patients. Potential new targets in corticotroph adenomas include the epidermal growth factor receptor, cyclin-dependent kinases, and heat shock protein 90. Osilodrostat and levoketoconazole are new inhibitors of steroidogenesis and are currently being evaluated in multicentre trials. CORT125134 is a new selective glucocorticoid receptor antagonist under investigation. We summarise the drug therapies for various forms of Cushing's syndrome and focus on emerging drugs and drug targets that have the potential for new and effective tailor-made pharmacotherapy for patients with Cushing's syndrome.
PMID: 30033041
ISSN: 2213-8595
CID: 4003412

Small intestinal neuroendocrine tumours and fibrosis: an entangled conundrum

Blažević, Anela; Hofland, Johannes; Hofland, Leo J; Feelders, Richard A; de Herder, Wouter W
Small intestinal neuroendocrine tumours (SI-NETs) are neoplasms characterized by their ability to secrete biogenic amines and peptides. These cause distinct clinical pathology including carcinoid syndrome, marked by diarrhoea and flushing, as well as fibrosis, notably mesenteric fibrosis. Mesenteric fibrosis often results in significant morbidity by causing intestinal obstruction, oedema and ischaemia. Although advancements have been made to alleviate symptoms of carcinoid syndrome and prolong the survival of patients with SI-NETs, therapeutic options for patients with mesenteric fibrosis are still limited. As improved insight in the complex pathogenesis of mesenteric fibrosis is key to the development of new therapies, we evaluated the literature for known and putative mediators of fibrosis in SI-NETs. In this review, we discuss the tumour microenvironment, growth factors and signalling pathways involved in the complex process of fibrosis development and tumour progression in SI-NETs, in order to elucidate potential new avenues for scientific research and therapies to improve the management of patients suffering from the complications of mesenteric fibrosis.
PMID: 29233841
ISSN: 1479-6821
CID: 4003342

Mesenteric fibrosis and palliative surgery in small intestinal neuroendocrine tumours

Blažević, Anela; Zandee, Wouter T; Franssen, Gaston J H; Hofland, Johannes; van Velthuysen, Marie-Louise F; Hofland, Leo J; Feelders, Richard A; de Herder, Wouter W
Mesenteric fibrosis (MF) surrounding a mesenteric mass is a hallmark feature of small intestinal neuroendocrine tumours (SI-NETs). Since this can induce intestinal obstruction, oedema and ischaemia, prophylactic resection of the primary tumour and mesenteric mass is often recommended. This study assessed the predictors for mesenteric metastasis and fibrosis and the effect of MF and palliative surgery on survival. A retrospective analysis of 559 patients with pathologically proven SI-NET and available CT-imaging data was performed. Clinical characteristics, presence of mesenteric mass and fibrosis on CT imaging and the effect of palliative abdominal surgery on overall survival were assessed. We found that MF was present in 41.4%. Older age, 5-HIAA excretion ≥67 μmol/24 h, serum CgA ≥121.5 μg/L and a mesenteric mass ≥27.5 mm were independent predictors of MF. In patients ≤52 years, mesenteric mass was less often found in women than in men (39% vs 64%, P = 0.002). Corrected for age, tumour grade, CgA and liver metastasis, MF was not a prognostic factor for overall survival. In patients undergoing palliative surgery, metastasectomy of mesenteric mass or prophylactic surgery did not result in survival benefit. In conclusion, we confirmed known predictors of MF and mesenteric mass and suggest a role for sex hormones as women ≤52 years have less often a mesenteric mass. Furthermore, the presence of MF has no effect on survival in a multivariate analysis, and we found no benefit of metastasectomy of mesenteric mass or prophylactic surgery on overall survival.
PMID: 29255095
ISSN: 1479-6821
CID: 4003352

Preoperative medical treatment in Cushing's syndrome: frequency of use and its impact on postoperative assessment: data from ERCUSYN

Valassi, Elena; Franz, Holger; Brue, Thierry; Feelders, Richard A; Netea-Maier, Romana; Tsagarakis, Stylianos; Webb, Susan M; Yaneva, Maria; Reincke, Martin; Droste, Michael; Komerdus, Irina; Maiter, Dominique; Kastelan, Darko; Chanson, Philippe; Pfeifer, Marija; Strasburger, Christian J; Tóth, Miklós; Chabre, Olivier; Krsek, Michal; Fajardo, Carmen; Bolanowski, Marek; Santos, Alicia; Trainer, Peter J; Wass, John A H; Tabarin, Antoine
BACKGROUND:Surgery is the definitive treatment of Cushing's syndrome (CS) but medications may also be used as a first-line therapy. Whether preoperative medical treatment (PMT) affects postoperative outcome remains controversial. OBJECTIVE:(1) Evaluate how frequently PMT is given to CS patients across Europe; (2) examine differences in preoperative characteristics of patients who receive PMT and those who undergo primary surgery and (3) determine if PMT influences postoperative outcome in pituitary-dependent CS (PIT-CS). PATIENTS AND METHODS/METHODS:1143 CS patients entered into the ERCUSYN database from 57 centers in 26 countries. Sixty-nine percent had PIT-CS, 25% adrenal-dependent CS (ADR-CS), 5% CS from an ectopic source (ECT-CS) and 1% were classified as having CS from other causes (OTH-CS). RESULTS: < 0.01). Within 6 months of surgery, no differences in morbidity or remission rates were observed between SX and PMT groups. CONCLUSIONS:PMT may confound the interpretation of immediate postoperative outcome. Follow-up is recommended to definitely evaluate surgical results.
PMID: 29440375
ISSN: 1479-683x
CID: 4003362

Unenhanced CT imaging is highly sensitive to exclude pheochromocytoma: a multicenter study

Buitenwerf, Edward; Korteweg, Tijmen; Visser, Anneke; Haag, Charlotte M S C; Feelders, Richard A; Timmers, Henri J L M; Canu, Letizia; Haak, Harm R; Bisschop, Peter H L T; Eekhoff, Elisabeth M W; Corssmit, Eleonora P M; Krak, Nanda C; Rasenberg, Elise; van den Bergh, Janneke; Stoker, Jaap; Greuter, Marcel J W; Dullaart, Robin P F; Links, Thera P; Kerstens, Michiel N
BACKGROUND:A substantial proportion of all pheochromocytomas is currently detected during the evaluation of an adrenal incidentaloma. Recently, it has been suggested that biochemical testing to rule out pheochromocytoma is unnecessary in case of an adrenal incidentaloma with an unenhanced attenuation value ≤10 Hounsfield Units (HU) at computed tomography (CT). OBJECTIVES/OBJECTIVE:We aimed to determine the sensitivity of the 10 HU threshold value to exclude a pheochromocytoma. METHODS:Retrospective multicenter study with systematic reassessment of preoperative unenhanced CT scans performed in patients in whom a histopathologically proven pheochromocytoma had been diagnosed. Unenhanced attenuation values were determined independently by two experienced radiologists. Sensitivity of the 10 HU threshold was calculated, and interobserver consistency was assessed using the intraclass correlation coefficient (ICC). RESULTS:214 patients were identified harboring a total number of 222 pheochromocytomas. Maximum tumor diameter was 51 (39-74) mm. The mean attenuation value within the region of interest was 36 ± 10 HU. Only one pheochromocytoma demonstrated an attenuation value ≤10 HU, resulting in a sensitivity of 99.6% (95% CI: 97.5-99.9). ICC was 0.81 (95% CI: 0.75-0.86) with a standard error of measurement of 7.3 HU between observers. CONCLUSION/CONCLUSIONS:The likelihood of a pheochromocytoma with an unenhanced attenuation value ≤10 HU on CT is very low. The interobserver consistency in attenuation measurement is excellent. Our study supports the recommendation that in patients with an adrenal incidentaloma biochemical testing for ruling out pheochromocytoma is only indicated in adrenal tumors with an unenhanced attenuation value >10 HU.
PMID: 29467230
ISSN: 1479-683x
CID: 4003372

Increased Urinary Extracellular Vesicle Sodium Transporters in Cushing Syndrome With Hypertension

Salih, Mahdi; Bovée, Dominique M; van der Lubbe, Nils; Danser, Alexander H J; Zietse, Robert; Feelders, Richard A; Hoorn, Ewout J
Context:Increased renal sodium reabsorption contributes to hypertension in Cushing syndrome (CS). Renal sodium transporters can be analyzed noninvasively in urinary extracellular vesicles (uEVs). Objective:To analyze renal sodium transporters in uEVs of patients with CS and hypertension. Design:Observational study. Setting:University hospital. Participants:The uEVs were isolated by ultracentrifugation and analyzed by immunoblotting in 10 patients with CS and 7 age-matched healthy participants. In 7 patients with CS, uEVs were analyzed before and after treatment. Main Outcome Measure:Abundance of protein in uEVs. Results:The 10 patients with CS were divided in those with suppressed and nonsuppressed renin-angiotensin-aldosterone system (RAAS; n = 5 per group). Patients with CS with suppressed RAAS had similar blood pressure but significantly lower serum potassium than patients with CS with nonsuppressed RAAS. Compared with healthy participants, only patients with suppressed RAAS had higher phosphorylated Na+-K+-Cl- cotransporter type 2 (pNKCC2) and higher total and phosphorylated Na+-Cl- cotransporter (pNCC) in uEVs. Serum potassium but not urinary free cortisol correlated with pNKCC2, pNCC, and Na+-Cl- cotransporter (NCC) in uEVs. Treatment of CS reversed the increases in pNKCC2, NCC, and pNCC. Conclusions:CS increases renal sodium transporter abundance in uEVs in patients with hypertension and suppressed RAAS. Potassium has recently been identified as an important driver of NCC activity, and low serum potassium may also contribute to increased renal sodium reabsorption and hypertension in CS. These results may also be relevant for hypertension induced by exogenous glucocorticoids.
PMID: 29726949
ISSN: 1945-7197
CID: 4003402

Epidrug-induced upregulation of functional somatostatin type 2 receptors in human pancreatic neuroendocrine tumor cells

Veenstra, Marije J; van Koetsveld, Peter M; Dogan, Fadime; Farrell, William E; Feelders, Richard A; Lamberts, Steven W J; de Herder, Wouter W; Vitale, Giovanni; Hofland, Leo J
Somatostatin receptors are a pivotal target for treatment of pancreatic neuroendocrine tumors (pNET), either with somatostatin analogues (SSA) or radiolabeled SSA. The highest affinity target for the most commonly used SSA is the somatostatin receptor type 2 (sst
PMCID:5871078
PMID: 29599907
ISSN: 1949-2553
CID: 4003392