Wnt-signaling has recently been identified as a regulator of a number of endocrine functions in health and disease in addition to its original attribution to developmental biology. Wnts are extracellular ligands on frizzled receptors and on lipoprotein receptor-related protein co-receptors. Ligand binding leads eventually to the activation of intracellular signaling cascades; based on the involvement of the transcriptional co-activator β-catenin it can be distinguished between canonical (i.e. β-catenin) and non-canonical Wnt-signaling. Recent studies revealed that canonical Wnt-signaling regulates the function of endocrine organs and contributes to a number of endocrine disorders. In this review, we would like to focus on a) recent mechanistic data on Wnts in pancreatic β-cell function; b) human genetic studies on Wnt signaling in type 2 diabetes mellitus; c) crosstalk between adipocytes and endocrine cells through Wnt-signaling molecules (with a focus on the role of Wnt-signaling in adrenocortical cells).
Sven Schinner, Holger S Willenberg, Matthias Schott and Werner A Scherbaum
Martin Späth, Svetlana Korovkin, Christiane Antke, Martin Anlauf and Holger S Willenberg
Current guidelines suggest proving angiotensin-independent aldosterone secretion in patients with primary aldosteronism (PA). It is further recommended to demonstrate unilateral disease because of its consequence for therapy. A general screening for excess secretion of other hormones is not recommended. However, clinically relevant autonomous aldosterone production rarely originates in adrenal tumors, compromised of zona glomerulosa cells only. This article reviews published data on aldosterone- and cortisol-co-secreting tumors and shows that pre-operative diagnosis of such a lesion is beneficial for patients. Overt or subclinical glucocorticoid hypersecretion may interfere with diagnostic studies, e.g. adrenal venous sampling, screening of familial forms of PA on the basis of serum 18-hydroxy-cortisol (18-OH-F) determination, and provoke glucocorticoid deficiency after surgical removal of the tumor. In addition, knowledge from histological and molecular studies in patients with aldosterone- and cortisol-co-secreting tumors challenges some concepts of the development of adrenal autonomy. The presence of an aldosterone- and cortisol-co-secreting adrenocortical tumor should be considered if a patient has i) PA and an adenoma that is larger than 2.5 cm, ii) cortisol that is non-suppressible with overnight low-dose dexamethasone, or iii) grossly elevated serum levels of hybrid steroids, such as 18-OH-F.
Anne Thiel, Anna-Carinna Reis, Matthias Haase, Gerald Goh, Matthias Schott, Holger S Willenberg and Ute I Scholl
Cortisol excess due to adrenal adenomas or hyperplasia causes Cushing's syndrome. Recent genetic studies have identified a somatic PRKACA L206R mutation as a cause of cortisol-producing adenomas. We aimed to compare the clinical features of PRKACA-mutant lesions with those of CTNNB1 mutations, and to search for similar mutations in unilateral hyperplasia or tumors co-secreting aldosterone.
Design, patients, and methods
In this study, 60 patients with cortisol excess who had adrenalectomies at our institution between 1992 and 2013 were assessed, and somatic mutations were determined by Sanger sequencing. A total of 36 patients had overt Cushing's syndrome, the remainder were subclinical: 59 cases were adenomas (three bilateral) and one was classified as hyperplasia. Four tumors had proven co-secretion of aldosterone.
Among cortisol-secreting unilateral lesions without evidence of co-secretion (n=52), we identified somatic mutations in PRKACA (L206R) in 23.1%, CTNNB1 (S45P, S45F) in 23.1%, GNAS (R201C) in 5.8%, and CTNNB1+GNAS (S45P, R201H) in 1.9%. PRKACA and GNAS mutations were mutually exclusive. Of the co-secreting tumors, two (50%) had mutations in KCNJ5 (G151R and L168R). The hyperplastic gland showed a PRKACA L206R mutation, while patients with bilateral adenomas did not have known somatic mutations. PRKACA-mutant lesions were associated with younger age, overt Cushing's syndrome, and higher cortisol levels vs non-PRKACA-mutant or CTNNB1-mutant lesions. CTNNB1 mutations were more significantly associated with right than left lesions.
PRKACA L206R is present not only in adenomas, but also in unilateral hyperplasia and is associated with more severe autonomous cortisol secretion. Bilateral adenomas may be caused by yet-unknown germline mutations.
Britta Heinze, Leonie J M Herrmann, Martin Fassnacht, Cristina L Ronchi, Holger S Willenberg, Marcus Quinkler, Nicole Reisch, Martina Zink, Bruno Allolio and Stefanie Hahner
The Li–Fraumeni tumor syndrome is strongly associated with adrenocortical carcinoma (ACC) and is caused by germline mutations in TP53 in 70% of cases. Also, TP53 polymorphisms have been shown to influence both cancer risk and clinical outcome in several tumor entities. We, therefore, investigated TP53 polymorphisms in a cohort of adult patients with ACC.
Evaluation of the role of TP53 polymorphisms in adult patients with ACC.
Subjects and methods
Peripheral blood for DNA extraction was collected from 72 ACC patients. Polymorphism analysis was carried out by amplification and sequencing of exons and adjacent intron sections of TP53. Results were correlated with clinical data and the distribution of the polymorphisms was compared with published Caucasian control groups.
Compared with control groups, genotype frequencies of analyzed TP53 polymorphisms among ACC patients were significantly different in three out of four polymorphisms: IVS2+38G>C (G/G, P=0.0248), IVS3ins16 (NoIns/NoIns, P<0.0001; NoIns/Ins, P<0.0001), and IVS6+62A>G (G/G, P<0.0001; G/A, P<0.0001). Overall, the survival of ACC patients, which harbored at least one of the less frequent genotype variants of four analyzed polymorphisms (n=23), was significantly inferior (median survival: 81.0 months in patients with the common homozygous genotypes vs 20.0 months in patients with the less frequent genotypes, HR 2.56, 95% CI 1.66–7.07; P=0.001). These results were confirmed by multivariable regression analysis (HR 2.84, 95% CI 1.52–7.17; P=0.037).
Some TP53 polymorphisms seem to influence overall survival in ACC patients. This effect was observed for a combination of polymorphic changes rather than for single polymorphisms.
Marianne Weigel, Anna Riester, Gregor Hanslik, Katharina Lang, Holger S Willenberg, Stephan Endres, Bruno Allolio, Felix Beuschlein, Martin Reincke and Marcus Quinkler
The saline infusion test (SIT) is widely used as a confirmatory test for primary aldosteronism (PA). SIT results are judged as follows: post-test aldosterone levels <50 ng/l exclude PA, whereas levels >50 ng/l confirm PA. We hypothesized that post-SIT aldosterone concentrations indicate the severity of PA and might predict outcome.
The study includes 256 PA patients of the German Conn's Registry who prospectively underwent SIT. The data of 126 patients with complete follow-up of 1.2±0.3 years after diagnosis were analyzed. The patients were divided into two groups with post-SIT aldosterone levels of 50–100 ng/l (group 1; n=38) and of >100 ng/l (group 2; n=88).
Patients in group 2 had a significantly shorter duration of hypertension (7.5 vs 11.7 years (median), P=0.014), higher systolic blood pressure (BP; 151±16 vs 143±17 mmHg, P=0.036), lower serum potassium (3.3±0.6 vs 3.5±0.4 mmol/l, P=0.006), higher 24-h urine protein excretion (7.4 vs 5.4 mg/dl (median), P=0.012), and were more often female (P=0.038). They showed more often unilateral disease (P<0.005) with larger tumors (14±10 vs 7±10 mm, P=0.021), underwent more often adrenalectomy (75% vs 37%, P<0.005), required a lower number of antihypertensive drugs after adrenalectomy (1.2±1.2 vs 2.5±1.4, P=0.001), had a faster normalization of urinary protein excretion (with medical treatment P=0.049; with Adx P<0.005) at follow-up, and more frequently underlying well-characterized mutation (P=0.047).
PA patients with post-SIT aldosterone levels of >100 ng/l have a more rapid development of PA caused more frequently by unilateral disease with larger aldosterone-producing adenomas. However, this group of patients may have a significantly better outcome following specific treatment.
Valeria Laufs, Barbara Altieri, Silviu Sbiera, Stefan Kircher, Sonja Steinhauer, Felix Beuschlein, Marcus Quinkler, Holger S Willenberg, Andreas Rosenwald, Martin Fassnacht and Cristina L Ronchi
Platinum-based chemotherapy (PBC) is the most effective cytotoxic treatment for advanced adrenocortical carcinoma (ACC). Excision repair cross complementing group 1 (ERCC1) plays a critical role in the repair of platinum-induced DNA damage. Two studies investigating the role of ERCC1 immunostaining as a predictive marker for the response to PBC in ACC had reported conflicting results. Both studies used the ERCC1-antibody clone 8F1 that later turned out to be not specific. The aim of this study was to evaluate the predictive role of ERCC1 with a new specific antibody in a larger series of ACC.
Design and methods
146 ACC patients with available FFPE slides were investigated. All patients underwent PBC (median cycles = 6), including cisplatin (n = 131) or carboplatin (n = 15), in most cases combined with etoposide (n = 144), doxorubicin (n = 131) and mitotane (n = 131). Immunostaining was performed with the novel ERCC1-antibody clone 4F9. The relationship between ERCC1 expression and clinicopathological parameters, as well as best objective response to therapy and progression-free survival (PFS) during PBC was evaluated.
High ERCC1 expression was observed in 66% of ACC samples. During PBC, 43 patients experienced objective response (29.5%), 49 stable disease (33.6%), 8 mixed response (5.5%) and 46 progressive disease (31.5%) without any relationship with the ERCC1 immunostaining. No significant correlation was also found between ERCC1 expression and progression-free survival (median 6.5 vs 6 months, P = 0.33, HR = 1.23, 95% CI = 0.82–2.0).
ERCC1 expression is not directly associated with sensitivity to PBC in ACC. Thus, other predictive biomarkers are required to support treatment decisions in patients with ACC.
Dirk Weismann, Mirko Peitzsch, Anna Raida, Aleksander Prejbisz, Maria Gosk, Anna Riester, Holger S Willenberg, Reiner Klemm, Georg Manz, Timo Deutschbein, Matthias Kroiss, Roland Därr, Martin Bidlingmaier, Andrzej Januszewicz, Graeme Eisenhofer and Martin Fassnacht
Reports conflict concerning measurements of plasma metanephrines (MNs) for diagnosis of pheochromocytomas/paragangliomas (PPGLs) by immunoassays compared with other methods. We aimed to compare the performance of a commercially available enzyme-linked immunoassay (EIA) kit with liquid chromatography–tandem mass spectrometric (LC–MS/MS) measurements of MNs to diagnose PPGLs.
In a substudy of a prospective, multicenter trial to study the biochemical profiles of monoamine-producing tumors, we included 341 patients (174 males and 167 females) with suspected PPGLs (median age 54 years), of whom 54 had confirmed PPGLs. Plasma MNs were measured by EIA and LC–MS/MS, each in a specialized laboratory.
Plasma normetanephrine (NMN) and MN were measured 60 and 39% lower by EIA than by LC–MS/MS. Using upper cut-offs stipulated for the EIA, diagnostic sensitivity was only 74.1% at a specificity of 99.3%. In contrast, use of similar cut-offs for MN and overall lower age-adjusted cut-offs for NMN measured by LC–MS/MS returned a diagnostic sensitivity and specificity of 98.1 and 99.7%. Areas under receiver-operating characteristic curves, nevertheless, indicated comparable diagnostic performance of the EIA (0.993) and LC–MS/MS (0.985). Diagnostic sensitivity for the EIA increased to 96.2% with a minimal loss in specificity (95.1%) following use of cut-offs for the EIA adapted to correct for the negative bias.
The EIA underestimates plasma MNs and diagnostic sensitivity is poor using commonly stipulated cut-offs, resulting in a high risk for missing patients with PPGLs. Correction of this shortcoming can be achieved by appropriately determined cut-offs resulting in comparable diagnostic performance of EIA and LC–MS/MS assays.
Gregor Hanslik, Henri Wallaschofski, Anna Dietz, Anna Riester, Martin Reincke, Bruno Allolio, Katharina Lang, Ivo Quack, Lars C Rump, Holger S Willenberg, Felix Beuschlein, Marcus Quinkler, Anke Hannemann and for the participants of the German Conn's Registry
Abnormalities in glucose homeostasis have been described in patients with primary aldosteronism (PA) but most studies show inconsistent results. Therefore, we aimed to compare the prevalence of type 2 diabetes mellitus and metabolic syndrome (MetS) in newly diagnosed PA patients to a matched control cohort of the background population.
In total, 305 PA patients of the prospective German Conn's Registry were compared to the population-based Study of Health In Pomerania (SHIP1; n=2454). A 1:1 match regarding sex, age, and BMI resulted in 269 matched pairs regarding type 2 diabetes and 183 matched pairs regarding MetS. Of the total, 153 PA patients underwent oral glucose tolerance testing (OGTT) at diagnosis and 38 PA patients were reevaluated at follow-up.
Type 2 diabetes and MetS were significantly more frequent in PA patients than in the control population (17.2% vs 10.4%, P=0.03; 56.8% vs 44.8%, P=0.02 respectively). Also, HbA1c levels were higher in PA patients than in controls (P<0.01). Of the total, 35.3% of non-diabetic PA patients showed an abnormal OGTT (¼ newly diagnosed type 2 diabetes and ¾ impaired glucose tolerance). PA patients with an abnormal OGTT at baseline presented with significantly improved 2 h OGTT glucose (P=0.01) at follow-up. We detected a negative correlation between 2 h OGTT glucose levels and serum potassium (P<0.01).
Type 2 diabetes and MetS are more prevalent in patients with PA than in controls matched for sex, age, BMI, and blood pressure. This may explain in part the increased cardiovascular disease morbidity and mortality in PA patients.
Daniel A Heinrich, Christian Adolf, Lars C Rump, Ivo Quack, Marcus Quinkler, Stefanie Hahner, Andrzej Januszewicz, Jochen Seufert, Holger S Willenberg, Nina Nirschl, Lisa Sturm, Felix Beuschlein and Martin Reincke
Primary aldosteronism (PA) is the most common endocrine form of arterial hypertension. The German Conn’s Registry’s purpose is to improve treatment outcomes of PA. We assessed whether key clinical, biochemical and epidemiological characteristics of newly diagnosed PA cases have changed over time, potentially indicating a different screening and referral practice in Germany evolving from 2008 to 2016.
The German Conn’s Registry is a multicenter database prospectively analyzing morbidity and long-term outcome of patients with PA.
Phenotypic changes between three year periods were calculated using Mann–Whitney U tests and Kruskal–Wallis tests for independent variables.
Over three time periods from 2008 to 2016, we noted a relative decrease of unilateral PA cases (67 vs 43%). Significantly more females were diagnosed with PA (33 vs 43%). Median daily defined drug doses decreased (3.1 vs 2.0) in the presence of unchanged SBP (150 vs 150 mmHg), plasma aldosterone (199 vs 173 ng/L) and PRC (3.2 vs 3.2 U/L). Median ARR values decreased (70 vs 47 ng/U) and median potassium levels at diagnosis (3.5 vs 3.7 mmol/L) increased as the percentage of normokalemic patients (25 vs 41%), indicating milder forms of PA.
Our results are in accordance with an increased screening intensity for PA. We identified a trend toward diagnosing milder forms, increasingly more females and less unilateral cases of PA.
Verena Fourkiotis, Oliver Vonend, Sven Diederich, Evelyn Fischer, Katharina Lang, Stephan Endres, Felix Beuschlein, Holger S Willenberg, Lars C Rump, Bruno Allolio, Martin Reincke, Marcus Quinkler and for the Mephisto Study Group
Primary aldosteronism (PA) has deleterious effects on kidney function independent of blood pressure levels. Up to now, data on effectiveness of different PA therapies regarding renal function are scarce.
Design and methods
This prospective multi-center study included 29 patients with newly diagnosed PA evaluated before and 1 year after treatment initiation, and a second cohort including 119 patients who were evaluated 5.3 and 6.8 years after treatment initiation. Glomerular filtration rate (GFR), spot urine albumin excretion/urinary creatinine (UAE/Ucrea) ratio, biochemical parameters, and 24-h blood pressure were measured. In a larger cross-sectional cohort, renal function was evaluated depending on the type of treatment (adrenalectomy (ADX; n=86); spironolactone (n=65); and eplerenone (n=18)).
GFR and UAE/Ucrea ratio significantly decreased in newly diagnosed PA patients after treatment initiation. In the second cohort, GFR and UAE/Ucrea ratio did not change during study period, and blood pressure was well controlled. In the larger cross-sectional cohort, no differences were seen in GFR and UAE/Ucrea ratio between PA patients on different treatment regimens. However, eplerenone treatment showed lower potassium levels and higher number of required antihypertensive medications.
Renal dysfunction with elevated albuminuria was seen in PA patients and was reversible after treatment initiation. Medical therapies with spironolactone or eplerenone seem to be as effective as ADX regarding renal function and blood pressure; however, sufficient daily doses need to be given.