Tamoxifen induces radioresistance through NRF2-mediated metabolic reprogramming in breast cancer

BACKGROUND

Recently, we reported that tamoxifen-resistant (TAM-R) breast cancer cells are cross-resistant to irradiation. Here, we investigated the mechanisms associated with tamoxifen-induced radioresistance, aiming to prevent or reverse resistance and improve breast cancer treatment.

METHODS

Wild-type ERα-positive MCF7 and ERα-negative MDA-MB-231 breast cancer cells and their TAM-R counterparts were analyzed for cellular metabolism using the Seahorse metabolic analyzer. Real-time ROS production, toxicity, and antioxidant capacity in response to H₂O₂, tamoxifen, and irradiation were determined. Tumor material from 28 breast cancer patients before and after short-term presurgical tamoxifen (ClinicalTrials.gov Identifier: NCT00738777, August 19, 2008) and cellular material was analyzed for NRF2 gene expression and immunohistochemistry. Re-sensitization of TAM-R cells to irradiation was established using pharmacological inhibition.

RESULTS

TAM-R cells exhibited decreased oxygen consumption and increased glycolysis, suggesting mitochondrial dysfunction. However, this did not explain radioresistance, as cells without mitochondria (Rho-0) were actually more radiosensitive. Real-time measurement of ROS after tamoxifen and H₂O₂ exposure indicated lower ROS levels and toxicity in TAM-R cells. Consistently, higher antioxidant levels were found in TAM-R cells, providing protection from irradiation-induced ROS. NRF2, a main activator of the antioxidant response, was increased in TAM-R cells and in tumor tissue of patients treated with short-term presurgical tamoxifen. NRF2 inhibition re-sensitized TAM-R cells to irradiation.

CONCLUSION

Mechanisms underlying tamoxifen-induced radioresistance are linked to cellular adaptations to persistently increased ROS levels, leading to cells with chronically upregulated antioxidant capacity and glycolysis. Pharmacological inhibition of antioxidant responses re-sensitizes breast cancer cells to irradiation.

Conditioning cortisol in humans: design and pilot study of a randomized controlled trial

Background

Conditioning of physiological responses can be achieved by repeatedly pairing a previously neutral conditioned stimulus with the administration of a pharmacologically salient unconditioned stimulus. This type of conditioning has been effective for specific immune and endocrine responses, but results with regard to conditioning of cortisol, a key stress-regulatory parameter, are currently unclear. This paper describes a pharmacological conditioning design, optimized for the examination of effects of cortisol conditioning under both basal conditions and in response to stress.

Methods

A double-blind randomized controlled conditioning paradigm aimed at conditioning of cortisol is conducted in 48 healthy female volunteers. During the acquisition phase, a gustatory stimulus (conditioned stimulus) is paired with hydrocortisone (100 mg, capsulated, unconditioned stimulus) three times before being administered together with placebo during three evocation sessions. To investigate possible effects of cortisol conditioning in response to stress, participants are exposed to the Trier Social Stress Test during the third evocation session. Primary outcome measure of this study is the mean area under the curve of salivary cortisol during the first two evocation sessions. As secondary outcomes, self-reported affect and stress as well as alpha-amylase are investigated. A pilot study was conducted to ensure that this design is feasible to be used in a larger study.

Discussion

This study design provides an innovative opportunity to examine the conditioning of cortisol under basal conditions and in response to stress. Also, the possible effect of cortisol conditioning on secondary outcomes of self-reported affect and alpha-amylase can be investigated. If cortisol could successfully be conditioned, this would be of conceptual relevance, showing that hypothalamic pituitary adrenal (HPA) axis regulation can be influenced by associative learning processes. Eventually, this could also have important clinical implications for understanding and treating stress-related disorders in which HPA axis dysregulation might play a role.

Trial registration

Nederlands Trial Register, NTR4651. Registered on 29 July 2014

Electronic supplementary material

The online version of this article (10.1186/s40814-018-0382-5) contains supplementary material, which is available to authorized users.

Can the FIGO 2000 scoring system for gestational trophoblastic neoplasia be simplified? A new retrospective analysis from a nationwide dataset

Background

Worldwide introduction of the International Fedaration of Gynaecology and Obstetrics (FIGO) 2000 scoring system has provided an effective means to stratify patients with gestational trophoblastic neoplasia to single- or multi-agent chemotherapy. However, the system is quite elaborate with an extensive set of risk factors. In this study, we re-evaluate all prognostic risk factors involved in the FIGO 2000 scoring system and examine if simplification is feasible.

Patients and methods

Between January 2003 and December 2012, 813 patients diagnosed with gestational trophoblastic neoplasia were identified at the Trophoblastic Disease Centre in London and scored using the FIGO 2000. Multivariable analysis and stepwise logistic regression were carried out to evaluate whether the FIGO 2000 scoring system could be simplified.

Results

Of the eight FIGO risk factors only pre-treatment serum human chorionic gonadotropin (hCG) levels exceeding 10 000 IU/l (OR = 5.0; 95% CI 2.5-10.4) and 100 000 IU/l (OR = 14.3; 95% CI 4.7-44.1), interval exceeding 7 months since antecedent pregnancy (OR = 4.1; 95% CI 1.0-16.2), and tumor size of over 5 cm (OR = 2.2; 95% CI 1.3-3.6) were identified as independently predictive for single-agent resistance. In addition, increased risk was apparent for antecedent term pregnancy (OR = 3.4; 95% CI 0.9-12.7) and the presence of five or more metastases (OR = 3.5; 95% CI 0.4-30.4), but patient numbers in these categories were relatively small. Stepwise logistic regression identified a simplified risk scoring model comprising age, pretreatment serum hCG, number of metastases, antecedent pregnancy, and interval but omitting tumor size, previous failed chemotherapy, and site of metastases. With this model only 1 out 725 patients was classified different from the FIGO 2000 system.

Conclusion

Our simplified alternative using only five of the FIGO prognostic factors appears to be an accurate system for discriminating patients requiring single as opposed to multi-agent chemotherapy. Further work is urgently needed to validate these findings.

The added value of hysterectomy in the management of gestational trophoblastic neoplasia

BACKGROUND

Despite the undoubted effectiveness of chemotherapeutic treatment in gestational trophoblastic neoplasia (GTN), problems related to toxicity of chemotherapy and chemo-resistant disease have led to reconsideration of the use of hysterectomy. Aim of the present study was to evaluate indications for and outcome of hysterectomy in patients with GTN in a nation-wide cohort.

METHODS

Between 1977 and 2012, we identified all patients diagnosed with GTN and treated with hysterectomy from the Dutch national databases. Demographics, clinical characteristics and follow-up were recorded retrospectively.

RESULTS

One hundred and nine patients (16.5% of all registered patients with GTN) underwent hysterectomy as part of their management for GTN. The majority of patients was classified as low-risk disease (74.3%), post-molar GTN (73.5%) and disease confined to the uterus (65.1%). After hysterectomy, complete remission was achieved in 66.2% of patients with localized disease and in 15.8% of patients with metastatic disease. For patients with localized disease, treated with primary hysterectomy, treatment duration was significantly shorter (mean 3.2weeks and 8.0weeks respectively, p=0.01) with lower number of administered chemotherapy cycles (mean 1.5 and 5.8 respectively, p<0.01) than patients in a matched control group.

CONCLUSION

In selected cases, a hysterectomy may be an effective means to either reduce or eliminate tumor bulk. Primary hysterectomy should mainly be considered in older patients with localized disease and no desire to preserve fertility, whereas patients with chemotherapy-resistant disease may benefit from additional hysterectomy, especially when disease is localized. For patients with widespread metastatic disease, the benefit of hysterectomy lies in the removal of chemotherapy-resistant tumor bulk with subsequent effect on survival.

Adrenal Steroid Metabolites Accumulating in Congenital Adrenal Hyperplasia Lead to Transactivation of the Glucocorticoid Receptor

Patients with congenital adrenal hyperplasia (CAH) are often clinically less severely affected by cortisol deficiency than anticipated from their enzymatic defect. We hypothesize that adrenal steroid hormone precursors that accumulate in untreated or poorly controlled CAH have glucocorticoid activity and partially compensate for cortisol deficiency. We studied the in vitro effects of 17-hydroxyprogesterone (17OHP), progesterone (P), 21-deoxycortisol (21DF), and androstenedione (Δ4) on the human glucocorticoid receptor (hGR). Competitive binding assays were performed in HeLa cells. Nuclear translocation of the hGR was studied by transfection of COS-7 cells with a GFP-tagged hGR and fluorescence microscopy. Transactivation assays were performed in COS-7 cells and in HEK 293 cells after cotransfection with hGR and luciferase reporter vectors using a dual luciferase assay. 17OHP, P, and 21DF are able to bind to the hGR with binding affinities of 24-43% compared with cortisol. Δ4 has a low binding affinity. Incubation with 21DF led to complete nuclear translocation of the hGR, whereas treatment with 17OHP or P resulted in partial nuclear translocation. 21DF transactivated the hGR with an EC50 approximately 6 times the EC50 of cortisol. 17OHP and P transactivated the hGR with EC50s of more than 100 times the EC50 of cortisol. No hGR transactivation was detected after incubation with Δ4. 21DF, 17OHP, and P are able to bind, translocate, and transactivate the hGR in vitro and thus may have glucocorticoid activity. 21DF might have a clinically relevant agonistic effect on the hGR and could potentially partially compensate the cortisol deficiency in CAH patients.

Genotype-specific differences in the tumor metabolite profile of pheochromocytoma and paraganglioma using untargeted and targeted metabolomics

CONTEXT AND OBJECTIVE

Pheochromocytomas and paragangliomas (PGLs) are neuroendocrine tumors of sympathetic or parasympathetic paraganglia. Nearly 40% of PGLs are caused by germline mutations. The present study investigated the effect of genetic alterations on metabolic networks in PGLs.

DESIGN

Homogenates of 32 sporadic PGLs and 48 PGLs from patients with mutations in SDHB, SDHD, SDHAF-2, VHL, RET, and NF-1 were subjected to proton ((1)H) nuclear magnetic resonance (NMR) spectroscopy at 500 MHz for untargeted and HPLC tandem mass spectrometry for targeted metabolite profiling.

RESULTS

(1)H NMR spectroscopy identified 28 metabolites in PGLs of which 12 showed genotype-specific differences. Part of these results published earlier reported low complex II activity (P < .0001) and low ATP/ADP/AMP content (P < .001) in SDH-related PGLs compared with sporadics and PGLs of other genotypes. Extending these results, low levels of N-acetylaspartic acid (NAA; P < .05) in SDH tumors and creatine (P < .05) in VHL tumors were observed compared with sporadics and other genotypes. Positive correlation was observed between NAA and ATP/ADP/AMP content (P < .001) and NAA and complex II activity (P < .0001) of PGLs. Targeted purine analysis in PGLs showed low adenine in cluster 1 compared with cluster 2 tumors (SDH P < .0001; VHL P < .05) whereas lower levels (P < .05) of guanosine and hypoxanthine were observed in RET tumors compared with SDH tumors. Principal component analysis (PCA) of metabolites could distinguish PGLs of different genotypes.

CONCLUSIONS

The present study gives a comprehensive picture of alterations in energy metabolism in SDH- and VHL-related PGLs and establishes the interrelationship of energy metabolism and amino acid and purine metabolism in PGLs.

Plasminogen activators are involved in angiostatin generation in vivo in benign and malignant ovarian tumor cyst fluids

In many tumor types, angiogenesis is the net result of pro- and anti-angiogenic mediators and correlated with metabolic activity, growth, and degree of malignancy. One of the first discovered anti-angiogenic compounds is angiostatin, a proteolytic fragment of plasminogen. The requirements for in vivo angiostatin generation have not yet been determined. We investigated the levels of plasminogen and angiostatin by western blotting and of components of the plasminogen activator complex by ELISA in cyst fluid derived from benign and malignant ovarian tumors. Fluid samples from functional ovarian follicles, dermoid cysts and endometriotic lesions were evaluated separately. When no or minimal amounts of plasminogen were present in the cyst fluids, angiostatin was generally absent as well, irrespective of plasminogen activator concentrations. When plasminogen was present, the degree of conversion of plasminogen to angiostatin was significantly correlated with the level of uPA, and, to a lesser extent, to the tPA level. However, angiostatin was also found in a number of cyst fluid samples with minimal or no plasminogen activators, suggesting the involvement of other angiostatin generating proteases in these samples. Conversely, no angiostatin was observed in a number of cyst fluid samples containing both plasminogen and plasminogen activators. The presence of an inhibitor of the enzymatic activity of uPA and/or tPA, like PAI-1, may explain this finding. Our data show that plasminogen activators are clearly involved in in vivo angiostatin formation in ovarian cysts. Most likely, however, other proteases, as well as inhibitors of plasminogen activators, are involved as well.

Pacemaker current inhibition in experimental human cardiac sympathetic activation: a double-blind, randomized, crossover study

Hyperpolarization-activated, cyclic nucleotide-gated 4 (HCN4) channels comprise the final pathway for autonomic heart rate (HR) regulation. We hypothesized that HCN4 inhibition could reverse autonomic imbalance in a human model of cardiac sympathetic activation. Nineteen healthy men ingested oral metoprolol+reboxetine, ivabradine+reboxetine, or placebo+reboxetine in a double-blind, randomized, crossover fashion. We assessed HR, blood pressure (BP), stroke volume, and cardiac output during rest and profound orthostatic stress. HR variability, BP variability, and baroreflex sensitivity were analyzed. Metoprolol, but not ivabradine, decreased resting HR and BP. Ivabradine attenuated the HR increase to orthostatic stress, albeit to a lesser extent than metoprolol. Stroke volume and cardiac output at a given HR were significantly lower with metoprolol. Unlike metoprolol, ivabradine did not affect HR variability, BP variability, or baroreflex sensitivity. Ivabradine attenuates sympathetic influences on HR at the sinus node level, leaving myocardial sympathetic activation unopposed. Reversal of parasympathetic dysfunction by ivabradine appears limited.

Association between thyroid function, thyroid autoimmunity, and state and trait factors of depression

OBJECTIVE

The aim of this study was to investigate whether thyroid function and thyroid peroxidase antibodies (TPOAb) are associated with depression, when using both state and trait parameters of depression.

METHOD

In 1125 participants of the Nijmegen Biomedical Study, thyroid-stimulating hormone (TSH), free thyroxine (FT4), and TPOAb were measured twice. The Beck Depression Inventory (BDI), a self-reported lifetime diagnosis of depression, and the neuroticism scale of the Eysenck Personality Questionnaire Revised Short Scale (EPQ-RSS) were used to evaluate the presence of state and trait features of depression.

RESULTS

We found no association between TSH and FT4 levels and BDI score, current depression, lifetime diagnosis of depression, and EPQ-RSS neuroticism score. Subjects with TPOAb had higher EPQ-RSS neuroticism scores in comparison with subjects without TPOAb, mean score 4.1 vs. 3.2 (regression coefficient 0.70; 95% CI 0.1-1.3; P-value 0.02 after adjustment for confounders). The prevalence of a lifetime diagnosis of depression was higher in subjects with positive TPOAb in comparison with participants without TPOAb: 24.2% vs. 16.7% (relative risk 1.4; 95% CI 1.0-2.1; P-value 0.04 after adjustment for confounders).

CONCLUSION

Thyroid peroxidase antibodies are positively associated with trait markers of depression. The presence of TPOAb may be a vulnerability marker for depression.

Human chorionic gonadotropin (hCG) regression normograms for patients with high-risk gestational trophoblastic neoplasia treated with EMA/CO (etoposide, methotrexate, actinomycin D, cyclophosphamide and vincristine) chemotherapy

BACKGROUND

We present normograms for human chorionic gonadotropin (hCG) regression in patients with high-risk gestational trophoblastic neoplasia (GTN) successfully treated with multiagent chemotherapy in order to predict treatment resistance.

PATIENTS AND METHODS

We collected data for 46 patients with high-risk GTN treated with EMA/CO (etoposide, methotrexate, actinomycin D, cyclophosphamide and vincristine) who had hCG values available. Patients were classified as having methotrexate (MTX)-resistant disease (n = 22) or primary high-risk disease (n = 24). The 10th, 50th and 90th percentiles of the hCG before every chemotherapy course were calculated and plotted in normograms.

RESULTS

Half of the patients treated for MTX-resistant disease and primary high-risk disease had normal hCG levels before the third and sixth course of chemotherapy, respectively. In patients with MTX-resistant disease, the 90th percentile line fell below normal before the start of the fourth course, whereas in patients with primary high-risk disease this was not the case until the eighth course of chemotherapy.

CONCLUSION

Resistance to EMA/CO treatment for high-risk GTN, as illustrated by examples, could be predicted using normograms for hCG resistance. Normograms differed depending on the indication for multiagent chemotherapy due to much higher initial hCG values in patients with primary high-risk disease compared with those treated for MTX-resistant disease.

Comparing cisplatin-based combination chemotherapy with EMA/CO chemotherapy for the treatment of high risk gestational trophoblastic neoplasia

BACKGROUND

Cisplatin-based chemotherapy (etoposide 100 mg/m(2) days 1-5, methotrexate 300 mg/m(2) day 1, cyclophosphamide 600 mg/m(2) day 1, actinomycin D 0.6 mg/m(2) day 2 and cisplatin 60 mg/m(2) day 4, EMACP) was compared to EMA/CO (etoposide 100 mg/m(2) days 1-2, methotrexate 300 mg/m(2) day 1 and actinomycin D 0.5 mg i.v. bolus day 1 and 0.5 mg/m(2) day 2, alternating with cyclophosphamide 600 mg/m(2) day 8 and vincristine 1 mg/m(2) day 8) for the treatment of high-risk gestational trophoblastic neoplasia (GTN).

PATIENTS AND METHODS

In the Netherlands, 83 patients were treated with EMACP and 103 patients with EMA/CO. Outcome measures were remission rate, median number of courses to achieve normal human chorionic gonadotrophin (hCG) concentrations, toxicity, recurrent disease rate and disease specific survival.

RESULTS

Remission rates were similar (EMACP 91.6%, EMA/CO 85.4%). The median number of courses of EMA/CO to reach hCG normalisation for single-agent resistant disease and primary high-risk disease was three and five courses, respectively, compared to 1.5 (p=0.001) and three (p<0.001) courses of EMACP. Patients treated with EMACP more often developed fever, renal toxicity, nausea and diarrhoea compared to patients treated with EMA/CO. Patients treated with EMA/CO more often had anaemia, neuropathy and hepatotoxicity.

CONCLUSION

EMACP combination chemotherapy is an effective treatment for high-risk GTN, with a remission rate comparable to EMA/CO. However, the difference in duration of treatment is only slightly shorter with EMACP. Cisplatin-based chemotherapy in the form of EMACP in this study was not proven more effective than EMA/CO.

Overexpression of the natural antisense hypoxia-inducible factor-1alpha transcript is associated with malignant pheochromocytoma/paraganglioma

Paragangliomas (PGLs) have widely different metastastic potentials. Two different types of PGLs can be defined by expression profiling. Cluster 1 PGLs exhibit VHL and/or succinate dehydrogenase (SDH) mutations and a pseudohypoxic phenotype. RET and neurofibromatosis type 1 (NF1) mutations occur in cluster 2 tumors characterized by deregulation of the RAS/RAF/MAP kinase signaling cascade. Sporadic PGLs can exhibit either profile. During sustained hypoxia, a natural antisense transcript of hypoxia-inducible factor 1 (aHIF) is expressed. The role of aHIF in the metastatic potential of PGL has not yet been investigated. The aim was to test the hypothesis that genotype-specific overexpression of aHIF is associated with an increased metastatic potential. Tumor samples were collected from 87 patients with PGL. Quantitative PCR was performed for aHIF, vascular endothelial growth factor (VEGF), aquaporin 3, cytochrome b561, p57Kip2, slit homolog 3, and SDHC. Expression was related to mutation status, benign versus malignant tumors, and metastasis-free survival. We found that both aHIF and VEGF were overexpressed in cluster 1 PGLs and in metastatic tumors. In contrast, slit homolog 3, p57Kip2, cytochrome b561, and SDHC showed overexpression in non-metastatic tumors, whereas no such difference was observed for aquaporin 3. Patients with higher expression levels of aHIF and VEGF had a significantly decreased metastasis-free survival. Higher expression levels of SDHC are correlated with an increased metastasis-free survival. In conclusion, we not only demonstrate a higher expression of VEGF in cluster 1 PGL, fitting a profile of pseudohypoxia and angiogenesis, but also of aHIF. Moreover, overexpression of aHIF and VEGF marks a higher metastatic potential in PGL.

Regulation of cytokine responses by seasonality of vitamin D status in healthy individuals

The immune modulating capacity of vitamin D(3) is well-recognized. Ultra-violet (UV) exposure determines production of vitamin D(3) in vivo and varies through the course of the year, especially in temperate regions. However, it is not known whether the human innate immune response differs due to seasonality. To validate the seasonal effects of vitamin D(3) , the effect of 1,25(OH)(2) D(3) on peripheral blood mononuclear cells (PBMC) cytokine response was first determined in vitro. 1,25(OH)(2) D(3) decreased interleukin (IL)-6 and tumour necrosis factor (TNF)-α release by PBMC stimulated with tripalmitoyl-S-glycerylcysteine (Pam3Cys) or lipopolysaccharide (LPS). Subsequently, ex-vivo stimulation studies were performed in 15 healthy volunteers through the course of the four seasons of the year. PBMC were isolated and stimulated with Toll-like receptor (TLR)-2 and TLR-4 ligands Pam3Cys and LPS, respectively. Circulating concentrations of 25(OH)D(3) and 1,25(OH)(2) D(3) were higher during summer (P<0·05) and a down-regulation of TLR-4-mediated IL-1β, IL-6, TNF-α, interferon (IFN)-γ and IL-10 production in summer was observed compared to winter (P<0·05). The variation in cytokine response upon TLR-2 (Pam3Cys) stimulation was moderate throughout the four seasons. The repressed cytokine production during the summer months could be explained partly by the reduced cell-membrane expression of TLRs. Physiological variation in vitamin D(3) status through the four seasons of the year can lead to alteration in the innate immune responses. Elevated vitamin D(3) level in vivo is associated with down-regulation of cytokine response through diminished surface expression of pattern recognition receptors.

How stress gets under the skin: cortisol and stress reactivity in psoriasis

BACKGROUND

Psychological stressors might contribute to the severity of chronic inflammatory diseases such as psoriasis by dysregulating hypothalamic-pituitary-adrenal (HPA) axis activity.

OBJECTIVES

To evaluate the role of cortisol, a key component of the HPA axis, in reaction to psychological stress in patients with psoriasis.

METHODS

Serum cortisol, clinical indicators of disease severity (Psoriasis Area and Severity Index) and self-report measures of daily stressors were measured monthly for 6 months in 62 patients with psoriasis.

RESULTS

In addition to the previous findings in this sample showing that peak levels of daily stressors predicted an increase in disease severity a month later, the peak levels of daily stressors were also significantly associated with a lower cortisol level. Moreover, patients who persistently experienced higher levels of daily stressors had lower mean cortisol levels than patients who experienced lower levels of daily stressors.

CONCLUSIONS

Results suggest that daily stressors influence disease outcome in patients with psoriasis by affecting cortisol levels at moments of high stress. Furthermore, patients with persistently high levels of stressors seem to have a specific psychophysiological profile of lowered cortisol levels and may be particularly vulnerable to the influence of stressors on their psoriasis.

Neurohumoral and metabolic response to exercise in water

Atrial natriuretic peptide (ANP) stimulates lipid mobilization and lipid oxidation in humans. The mechanism appears to promote lipid mobilization during exercise. We tested the hypothesis that water immersion augments exercise-induced ANP release and that the change in ANP availability is associated with increased lipid mobilization and lipid oxidation. In an open randomized and cross-over fashion we studied 17 men (age 31+/-3.6 years; body mass index 24+/-1.7 kg/m(2); body fat 17+/-6.7%) on no medication. Subjects underwent two incremental exercise tests on a bicycle ergometer. One test was conducted on land and the other test during immersion in water up to the xiphoid process. In a subset (n=7), we obtained electromyography recordings in the left leg. We monitored gas exchange, blood pressure, and heart rate. In addition, we obtained blood samples towards the end of each exercise step to determine ANP, norepinephrine, epinephrine, lactate, free fatty acids, insulin, and glucose concentrations. Heart rate, systolic blood pressure, and oxygen consumption at the anaerobic threshold and during peak exercise were similar on land and with exercise in water. The respiratory quotient was mildly reduced when subjects exercised in water. Glucose and lactate measurements were decreased whereas free fatty acid concentrations were increased with exercise in water. Water immersion attenuated epinephrine and norepinephrine and augmented ANP release during exercise. Even though water immersion blunts exercise-induced sympathoadrenal activation, lipid mobilization and lipid oxidation rate are maintained or even improved. The response may be explained by augmented ANP release.

Acute psychomotor effects of MDMA and ethanol (co-) administration over time in healthy volunteers

In Western societies, a considerable percentage of young people use 3,4-methylenedioxymethamphetamine (MDMA or 'ecstasy'). The use of alcohol (ethanol) in combination with ecstasy is common. The aim of the present study was to assess the acute psychomotor and subjective effects of (co-) administration of MDMA and ethanol over time and in relation to the pharmacokinetics. We performed a four-way, double blind, randomized, crossover, placebo-controlled study in 16 healthy volunteers (nine men, seven women) between the ages of 18 and 29. MDMA (100 mg) was given orally while blood alcohol concentration was maintained at pseudo-steady state levels of approximately 0.6 per thousand for 3 h by a 10% intravenous ethanol clamp. MDMA significantly increased psychomotor speed but did not affect psychomotor accuracy and induced subjective arousal. Ethanol impaired both psychomotor speed and accuracy and induced sedation. Coadministration of ethanol and MDMA improved psychomotor speed but impaired psychomotor accuracy compared with placebo and reversed ethanol-induced sedation. Pharmacokinetics and pharmacodynamics showed maximal effects at 90-150 min after MDMA administration after which drug effects declined in spite of persisting MDMA plasma concentration, with the exception of ethanol-induced sedation, which manifested itself fully only after the infusion was stopped. In conclusion, results show that subjects were more aroused when intoxicated with both substances combined compared with placebo, but psychomotor accuracy was significantly impaired. These findings may have implications for general neuropsychological functioning as this may provide a sense of adequate performance that does not agree with a significant reduction in psychomotor accuracy.

Ethanol co-administration moderates 3,4-methylenedioxymethamphetamine effects on human physiology

Alcohol is frequently used in combination with 3,4-methylenedioxymethamphetamine (MDMA). Both drugs affect cardiovascular function, hydration and temperature regulation, but may have partly opposing effects. The present study aims to assess the acute physiologic effects of (co-) administration of MDMA and ethanol over time. A four-way, double blind, randomized, crossover, placebo-controlled study in 16 healthy volunteers (9 male and 7 female) between the ages of 18 and 29. MDMA (100 mg) was given orally and blood ethanol concentration was maintained at pseudo-steady state levels of 0.6 per thousand by a three-hour 10% intravenous ethanol clamp. Cardiovascular function, temperature and hydration measures were recorded throughout the study days. Ethanol did not significantly affect physiologic function, with the exception of a short lasting increase in heart rate. MDMA potently increased heart rate and blood pressure and induced fluid retention as well as an increase in temperature. Co-administration of ethanol with MDMA did not affect cardiovascular function compared to the MDMA alone condition, but attenuated the effects of MDMA on fluid retention and showed a trend for attenuation of MDMA-induced temperature increase. In conclusion, co-administration of ethanol and MDMA did not exacerbate physiologic effects compared to all other drug conditions, and moderated some effects of MDMA alone.

Increased oxytocin concentrations and prosocial feelings in humans after ecstasy (3,4-methylenedioxymethamphetamine) administration

MDMA (3,4-methylenedioxymethamphetamine or "ecstasy") is a recreationally used drug with remarkable and characteristic prosocial effects. In spite of abundant attention in the scientific literature, the mechanism of its prosocial effects has not been elucidated in humans. Recently, research in animals has suggested that the neuropeptide oxytocin may induce these effects. In a double blind, randomized, crossover, and placebo-controlled study in 15 healthy volunteers we assessed blood oxytocin and MDMA concentrations and subjective prosocial effects after oral administration of 100 mg MDMA or placebo. MDMA induced a robust increase of blood oxytocin concentrations and an increase of subjective prosocial feelings. Within subjects, the variations in these feelings were significantly and positively correlated with variation in oxytocin levels, and the correlations between these feelings and oxytocin were significantly stronger than those between these feelings and blood MDMA levels. MDMA induces oxytocin release in humans, which may be involved in the characteristic prosocial effects of ecstasy.

Testicular adrenal rest tumours in congenital adrenal hyperplasia

In adult patients with congenital adrenal hyperplasia (CAH) the presence of testicular adrenal rest tumours (TART) is an important cause of gonadal dysfunction and infertility. In the last decade several papers have focused on the origin and pathogenesis of these tumours. In this paper we review the embryological, histological, biochemical and clinical features of TART and discuss the treatment options. Furthermore, we propose a new five-stage classification of TART, based on sonographic, clinical and biochemical parameters, that may lead to a better follow up and treatment of patients with TART.

Methylated genes as new cancer biomarkers

Aberrant hypermethylation of promoter regions in specific genes is a key event in the formation and progression of cancer. In at least some situations, these aberrant alterations occur early in the formation of malignancy and appear to be tumour specific. Multiple reports have suggested that measurement of the methylation status of the promoter regions of specific genes can aid early detection of cancer, determine prognosis and predict therapy responses. Promising DNA methylation biomarkers include the use of methylated GSTP1 for aiding the early diagnosis of prostate cancer, methylated PITX2 for predicting outcome in lymph node-negative breast cancer patients and methylated MGMT in predicting benefit from alkylating agents in patients with glioblastomas. However, prior to clinical utilisation, these findings require validation in prospective clinical studies. Furthermore, assays for measuring gene methylation need to be standardised, simplified and evaluated in external quality assurance programmes. It is concluded that methylated genes have the potential to provide a new generation of cancer biomarkers.

Harmonisation of multi-centre real-time reverse-transcribed PCR results of a candidate prognostic marker in breast cancer: an EU-FP6 supported study of members of the EORTC - PathoBiology Group

AIM

Assessment of intra- and inter-laboratory variation in multi-centre real-time reverse-transcribed PCR (qRT-PCR)-based mRNA quantification of a prognostic marker in breast cancer using external quality assurance (EQA).

METHODS

A questionnaire on the methodologies used and EQA calibrators were sent to 5 participating laboratories from 4 European countries, which measured mRNA levels of PITX2 splice variants and reference genes by qRT-PCR.

RESULTS

Differences in the methodology included PCR quantification methodology and equipment, RNA extraction and cDNA synthesis procedures. The intra-laboratory coefficient of variation (CV) ranged from 5 to 23%, and the inter-laboratory CV ranged from 17 to 30%. The inter-laboratory CV was reduced to 13% by using prediluted calibrators and by harmonising the data in the central QA laboratory. Additional normalisation using reference genes did not decrease the variation further.

CONCLUSIONS

Both externally provided calibrators and centralised harmonisation are required to reduce the intra-laboratory variation in multi-centre qRT-PCR results to an acceptable level.

Angiogenesis, hypoxia and VEGF expression during tumour growth in a human xenograft tumour model

Tumour growth and spread of tumour cells requires angiogenesis. Incipient angiogenesis is not induced by tumour cell hypoxia but probably by proangiogenic factors. During growth tumours depend on a further induction of vascular development for adequate oxygen and nutrient supply. If the oxygen supply is insufficient, the resulting hypoxia stimulates angiogenesis through upregulation of HIF-1 alpha and VEGF. VEGF upregulation is associated with a poor response to treatment and poor prognosis. The aim of the study was to analyze the interrelationship between hypoxia and angiogenesis during tumour growth. Therefore the tumour vasculature architecture and functional properties of the vessels were studied during subsequent phases of tumour growth in relation to hypoxia and VEGF-expression. Tumours from the human glioblastoma multiforme tumour line E106 were transplanted in athymic mice. Tumours were harvested at 2 days after transplantation and when tumours reached a mean size of 2, 4, 6, 8 and 10 mm. VEGF was present early in the onset of angiogenesis independent of HIF-1 alpha. During tumour growth VEGF increased from 0.94 to 7.27 ng/mg assessed by ELISA. However, there was increasing intratumoural heterogeneity in the architecture of the tumours, even in the largest tumours small well oxygenated areas were detected resembling the relatively well organized architecture of the smallest tumours. The observation that tumour vasculature develops in early phases under normoxic and at later phases under hypoxic conditions with the presence of both conditions in the larger tumours, suggested that anti-angiogenic therapy should be directed towards HIF-1 alpha dependent and HIF 1-alpha independent pathways.

Metastases but not cardiovascular mortality reduces life expectancy following surgical resection of apparently benign pheochromocytoma

The treatment of choice for non-metastatic pheochromocytoma is surgical resection. Its goals are to abolish catecholamine hypersecretion, normalize blood pressure, and prevent further tumor growth or progression to metastatic disease. Data on long-term mortality and morbidity after pheochromocytoma surgery are limited. We here report a retrospective study on the long-term outcome after surgery for apparently benign pheochromocytoma at the Radboud University Nijmegen Medical Centre. Data on clinical presentation, treatment, post-surgical blood pressure and recurrence, metastasis and death were collected of 69 consecutive patients (January 1966-December 2000; follow-up: until death or January 2006). Survival was compared with survival of a matched reference population. Two patients died of surgical complications. All ten patients with metastatic disease (including three diagnosed at first surgery) died. At follow-up, 40 patients were alive and recurrence free and three patients were lost to follow up. Two patients experienced a benign recurrence. Mean+/-s.d. follow-up was 10.2+/-7.5 (median 9, range 1-38) years. Kaplan-Meier estimates for 5- and 10-year survival since surgery were 85.8% (95% CI: 77.2-94.4%) and 74.2% (95% CI: 62.0-86.4%) for patients versus 95.5 and 89.4% in the reference population (P<0.05). Sixty-four percent of all patients with hypertension prior to surgery showed a significant decrease in blood pressure, but remained hypertensive after surgery. In conclusion, compared with the general population patients have a reduced life expectancy following pheochromocytoma surgery, due to their risk of developing metastatic disease. Only one-third becomes normotensive without antihypertensive medication. Therefore, lifelong follow-up is warranted.

Thyroid function in patients with proteinuria

BACKGROUND

Patients with proteinuria may suffer from substantial losses of functional proteins such as hormones and hormone-binding proteins. A limited number of studies have reported urinary losses of thyroid hormones and thyroxin-binding globulin. Overt hypothyroidism attributable to these urinary losses has been described. However, the impact of proteinuria on thyroid function parameters has not been studied in a large patient cohort.

METHODS

We evaluated thyroid function parameters in patients with proteinurea who are negative to thyroxine peroxidase antibodies (TPOAbs). Values of free thyroxin and thyroid-stimulating hormone (TSH) were compared with data from age- and gender-matched controls derived from the Nijmegen Biomedical Study, a population-based survey conducted in our hospital.

RESULTS

We evaluated 159 patients. There were 111 males and 48 females. Median (IQR) age was 52 (40 to 62) years, serum creatinine concentration 99 (82 to 134) micromol/l, serum albumin concentration 29 (22 to 35) g/l, and proteinuria 6.6 (3.1 to 10.9) g/10 mmol creatinine. Median TSH was significantly higher in the patients than the controls (1.81 mU/l vs 1.34 mU/l, p.<0.001); however, overt hypothyroidism was observed in only one patient.

CONCLUSION

Patients with proteinuria have higher TSH levels, consistent with urinary loss of thyroid hormones. However, these urinary losses do not result in overt, clinically relevant, hypothyroidism. The role of subclinical hypothyroidism in these patients needs further evaluation.

A decrease of plasma macrophage migration inhibitory factor concentration is associated with lower numbers of circulating lymphocytes in experimental Plasmodium falciparum malaria

Macrophage migration inhibitory factor (MIF) has recently been implicated in the pathogenesis of malarial anaemia. However, field studies have reported contradictory results on circulating MIF concentrations in patients with clinically overt Plasmodium falciparum malaria. We determined plasma MIF levels over time in 10 healthy volunteers during experimental P. falciparum infection. Under fully controlled conditions, MIF levels decreased significantly during early blood-stage infection and reached a nadir at day 8 post-infection. A decrease in the number of circulating lymphocytes, which are an important source of MIF production, paralleled the decrease in MIF levels. Monocyte/macrophage counts remained unchanged. At MIF nadir, the anti-inflammatory cytokine interleukin (IL)-10, which is an inhibitor of T-cell MIF production, was detectable in only 2 of 10 volunteers. Plasma concentrations of the pro-inflammatory cytokines IL-8 and IL-1beta were only marginally elevated. We conclude that circulating MIF levels decrease early in blood-stage malaria as a result of the decline in circulating lymphocytes.

CSF levels of growth factors and plasminogen activators in leptomeningeal metastases

OBJECTIVE

To investigate the diagnostic value of transforming growth factor beta(1) (TGFbeta(1)), vascular endothelial growth factor (VEGF), urokinase-type plasminogen activator (uPA), and tissue-type plasminogen activator (tPA) in CSF for leptomeningeal metastasis (LM).

METHODS

The authors measured concentrations of biomarkers by ELISA in matched samples of CSF and serum, collected from 132 patients with a solid malignancy with LM (n = 19) and without LM (n = 54) and patients with viral (n = 16) and bacterial (n = 16) meningitis and a variety of nonmalignant, noninfectious neurologic disorders (n = 27). Indexes of the biomarkers (CSF/serum value relative to CSF/serum albumin ratios) were calculated to correct for the serum contribution to the CSF marker concentration.

RESULTS

CSF VEGF concentration was significantly higher in LM than in all other groups. VEGF indexes were also higher, although not significant. In contrast, the tPA index was significantly decreased in LM compared with all other groups. The combination of the VEGF and tPA indexes resulted in a sensitivity of 100% for LM and a specificity of 73% for the patient group with a primary tumor but without LM.

CONCLUSION

Patients with leptomeningeal metastasis have high vascular endothelial growth factor (VEGF) indexes and low tissue-type plasminogen activator (tPA) indexes. As cytologic examination of CSF lacks 100% sensitivity for the diagnosis of leptomeningeal metastasis (LM), the combination VEGF and tPA index analysis may be of additional value in the diagnostic workup of patients suspected of having LM.

Absence of exercise-induced leptin suppression associated with insufficient epinephrine reserve in patients with classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency

OBJECTIVE

Patients with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency suffer from glucocorticoid and mineralocorticoid deficiency. They have insufficient epinephrine reserves and increased basal leptin levels and are often insulin resistant. In healthy subjects, an inhibitory effect of acute catecholamine elevation on the leptin plasma concentrations has been reported. However, it is not yet known how leptin levels respond to exercise in CAH patients.

METHODS

We performed a cycle ergometer test in six CAH patients to measure the response of plasma leptin, glucose and the catecholamines, epinephrine (E) and norepinephrine (N), as well as their respective metabolites, metanephrine (M) and normetanephrine (NM), to intense exercise.

RESULTS

Baseline leptin concentrations in CAH patients were not different from those of controls. Leptin levels decreased significantly with exercise in healthy controls, whereas they remained unchanged in CAH patients. In contrast to controls, CAH patients showed no rise of plasma glucose. Basal and stimulated E and M levels were significantly lower in CAH patients compared to controls. Baseline and stimulated N and NM levels were comparable, showing a significant rise after exercise. Peak systolic blood pressure and peak heart rate in both groups were comparable.

CONCLUSION

CAH patients do not manifest exercise-induced leptin suppression. The most probable reason for this is their severely impaired epinephrine stress response. In addition, epinephrine deficiency is leading to secondary changes in various catecholamine dependent metabolic pathways, e. g., energy balance. Although obvious clinical sequelae are so far unknown, the catecholamine-deficient state and the resulting hyperleptinemia might contribute to the severity of the disease in CAH.

Clinical utility of hyperglycosylated hCG in serum taken before hydatidiform mole evacuation to predict persistent trophoblastic disease

OBJECTIVE

Human chorionic gonadotropin (hCG) is widely used in the management of hydatidiform mole and persistent trophoblastic disease (PTD). Studies on hyperglycosylated human chorionic gonadotropin (invasive trophoblast antigen, ITA) in PTD are limited. In serum samples taken before evacuation of molar pregnancies we measured the concentrations of free hCG beta-subunit (free hCGbeta), "total" hCG (hCG+hCGbeta) and ITA, and determined whether ITA, the two other hCG analytes, or the calculated ratios of hCGbeta/hCG+hCGbeta, hCGbeta/ITA and hCG+hCGbeta/ITA could predict the later development of PTD.

DESIGN

A retrospective study based on blood specimens collected in the Dutch Central Registry for Hydatidiform Moles. The study group comprised 97 patients with hydatidiform moles who did not develop PTD after mole evacuation and 33 patients who did develop PTD.

METHODS

Serum samples from 130 patients with hydatidiform mole with or without PTD were assayed using specific (radio)immunoassays for free hCGbeta, total hCG, and ITA. From these analytes we also calculated the ratios hCGbeta/hCG+hCGbeta, hCGbeta/ITA, and hCG+hCGbeta/ITA. To predict the development of PTD from these analytes and parameters we performed receiver-operating characteristic (ROC) curve analysis, resulting in areas under the curve (AUCs) that represented the diagnostic accuracy which was rated in a range from excellent (AUC >0.9 or <0.1) to poor (AUC 0.4-0.6).

RESULTS

The diagnostic accuracy of ITA was moderate (0.618) and not different from that of free hCGbeta (0.610) and hCG+hCGbeta (0.622).

CONCLUSIONS

ITA as well as the other analytes and parameters in serum taken prior to evacuation from patients with molar pregnancies cannot be used to predict the subsequent development of persistent trophoblastic disease.