Midgut neuroendocrine tumor patients have a depleted gut microbiome with a discriminative signature

Rationale: When compared to other types of cancer, the prevalence of midgut neuroendocrine tumors (NET) has disproportionally increased over the past decades. To date, there has been very little progress in discovering (epi)genetic drivers and treatment options for these tumors. Recent microbiome research has revealed that enteroendocrine cells communicate with the intestinal microbiome and has provided novel treatment targets for various other cancer types. Hence, our aim was to analyze the role of the gut microbiome in midgut NET patients. Methods: Fecal samples, prospectively collected from patients and control subjects, were analyzed with next generation 16S sequencing. Patients with neuroendocrine carcinomas and recent antibiotics use were excluded. Relevant variables were extracted from questionnaires and electronic health records. Microbial composition was compared between patients and controls as well as between groups within the patient cohort. Results: 87 midgut NET patients and 95 controls were included. Midgut NET patients had a less rich and diverse gut microbiome than controls (p &lt; 0.001). Moreover, we identified 31 differentially abundant species and a gut microbial signature consisting of 17 species that was predictive of midgut NET presence with an area under the receiver operating characteristic curve of 0.863. Gut microbial composition was not directly associated with the presence of the carcinoid syndrome, tumor grade or multifocality. Nonetheless, we did observe a potential link between microbial diversity and the presence of carcinoid syndrome symptoms within the subset of patients with elevated 5-hydroxyindolacetic acid levels. Conclusion: Midgut NET patients have an altered gut microbiome which suggests a role in NET development and could provide novel targets for microbiome-based diagnostics and therapeutics.</p

In active acromegaly, IGF1 bioactivity is related to soluble Klotho levels and quality of life

The value of measuring IGF1 bioactivity in active acromegaly is unknown. Soluble Klotho (S-Klotho) level is elevated in active acromegaly and it has been suggested that S-Klotho can inhibit activation of the IGF1 receptor (IGF1R). A cross-sectional study was carried out in 15 patients with active acromegaly based on clinical presentation, unsuppressed GH during an oral glucose tolerance test, and elevated total IGF1 levels (>+2 s.d.). Total IGF1 was measured by immunoassay, IGF1 bioactivity by the IGF1R kinase receptor activation assay and S-Klotho by an ELISA. Quality of Life (QoL) was assessed by Acromegaly QoL (AcroQoL) Questionnaire and Short-Form-36 Health Survey Questionnaire (SF-36). Out of 15 patients, nine had IGF1 bioactivity values within the reference range. S-Klotho was higher in active acromegaly compared with controls. Age-adjusted S-Klotho was significantly related to IGF1 bioactivity (r=0.75, P=0.002) and to total IGF1 (r=0.62, P=0.02). IGF1 bioactivity and total IGF1 were inversely related to the physical component summary of the SF-36 (r=−0.78, P=0.002 vs r=−0.60, P=0.03). Moreover, IGF1 bioactivity, but not total IGF1, was significantly inversely related to the physical dimension of the AcroQoL Questionnaire (r=−0.60, P=0.02 vs r=−0.37, P=0.19). In contrast to total IGF1, IGF1 bioactivity was within the reference range in a considerable number of subjects with active acromegaly. Elevated S-Klotho levels may have reduced IGF1 bioactivity. Moreover, IGF1 bioactivity was more strongly related to physical measures of QoL than total IGF1, suggesting that IGF1 bioactivity may better reflect physical limitations perceived in active acromegaly

Adolescent weak decoders writing in a shallow orthography: process and product

It has been hypothesised that students with dyslexia struggle with writing because of a word level focus that reduces attention to higher level textual features (structure, theme development). This may result from difficulties with spelling and/or from difficulties with reading. 26 Norwegian upper secondary students (M = 16.9 years) with weak decoding skills and 26 age-matched controls composed expository texts by keyboard under two conditions: normally and with letters masked to prevent them reading what they were writing. Weak decoders made more spelling errors and produced poorer quality text. Their inter key-press latencies were substantially longer pre-word, at word-end, and within-word. These findings provide some support for the word-level focus hypothesis, although we found that weak decoders were slightly less likely to engage in word-level editing. Masking did not affect differences between weak decoders and controls indicating that reduced fluency was associated with production rather than monitoring what they had produced

17-β-Estradiol-dependent regulation of somatostatin receptor subtype expression in the 7315b prolactin secreting rat pituitary tumor in vitro and in vivo

In the present study, we have investigated the role of estrogens in the regulation of somatostatin receptor subtype (sst) expression in 7315b PRL- secreting rat pituitary tumor cells in vitro and in vivo. sst were undetectable in freshly dispersed cells of the transplantable 7315b tumor. When 7315b cells were cultured in medium containing 10% FCS, the number of high affinity sst increased with prolonged culture time. However, when the medium was supplemented with 10% horse serum (HS) instead of FCS, no sst were detectable on 7315b cells even after three weeks of culturing. In contrast to HS, FCS contains high E2-levels (HS, 8 pM; FCS, 134 pM). The antiestrogen tamoxifen (0.5 μM) significantly inhibited the sst number to 50.5% of the value of untreated FCS-grown cells, suggesting that E2 stimulates sst expression in 7315b rat pituitary tumor cells. E2 (l0 nM) induced a rapid increase in sst number in HS-grown 7315b cells. Octreotide (1μM) significantly inhibited PRL release and the intracellular PRL concentration of 7315b cells that were cultured in medium supplemented with FCS or with HS + l0 nM E2 but not in HS alone. This indicates that the sst present on these cells are biologically active. RT-PCR analysis revealed that none of the five currently known sst subtypes were present in freshly dispersed 7315b pituitary tumor cells. The expression of sst2- and sst3- messenger RNA (mRNA) was unequivocally correlated to the presence of E2 because these sst subtypes were detected only in cells that were cultured for7 and 14 days in medium supplemented with FCS or with HS + 10 nM E2. sst1, sst4 and sst5 messenger RNA could not be detected. The 7315b tumor itself synthesizes and secretes huge amounts of PRL. The high PRL levels in tumor-bearing rats inhibit the ovarian E2-production. No detectable E2 levels could be measured in the serum of 7315b tumor-bearing rats. The sc administration of 20 μg/day E2-benzoate normalized the circulating E2 levels in 7315b tumor- bearing rats. Moreover, E2-treatment indeed induced sst expression in vivo as shown by ligand binding studies using membrane homogenates and [125I- Tyr3]-octreotide as radioligand and by autoradiography on tissue sections. In agreement with the in vitro studies, the expression of the sst2 subtype was established by RT-PCR analysis in 7315b tumors of E2-treated rats. However, in contrast to the in vitro studies. E2-treatment did not effectuate the expression of the sst3 subtype, suggesting that the in vitro stimulus of E2 is stronger. In conclusion: 1) sst2 and sst3 expression in the 7315b rat prolactinoma model is primarily dependent upon the presence of estrogens; 2) the antihormonal action of octreotide in 7315b tumor cells in vitro is mediated via the sst2 and/or sst3 subtypes; 3) the absence of sst expression in vivo can be explained by the hormonal environment of the 7315b tumor cells. The 7315b tumor cells in vivo may down-regulate their own receptor status via their host, because of the ensuing hyperprolactinemia results in a hypo-estrogenic state.</p

IGF-I Bioactivity in an Elderly Population: Relation to Insulin Sensitivity, Insulin Levels, and the Metabolic Syndrome

OBJECTIVE - There is a complex relationship between IGF-I, IGF binding proteins, growth hormone, and insulin. The IGF-I kinase receptor activation assay (KIRA) is a novel method for measuring IGF-I bioactivity in human serum. We speculated that determination of IGF-I bioactivity might broaden our understanding of the IGF-I system in subjects with the metabolic syndrome. The purpose of our study was to investigate whether IGF-I bioactivity was related to insulin sensitivity and the metabolic syndrome. RESEARCH DESIGN AND METHODS - We conducted a cross-sectional study embedded in a random sample (1,036 elderly subjects) of a prospective population-based cohort study. IGF-I bioactivity was determined by the IGF-I KIRA. Categories of glucose (in)tolerance were defined by the 2003 American Diabetes Association criteria. Insulin sensitivity was assessed by homeostasis model assessment. The Adult Treatment Panel III definition of the metabolic syndrome was used. RESULTS - In subjects with normal fasting glucose and impaired fasting glucose, IGF-I bioactivity progressively increased with increasing insulin resistance, peaked at fasting glucose levels just below 7.0 mmol/l, and dropped at higher glucose levels. Mean IGF-I bioactivity peaked when three criteria of the metabolic syndrome were present and then declined significantly when five criteria of the metabolic syndrome were present. CONCLUSIONS - We observed that IGF-I bioactivity was related to insulin sensitivity, insulin levels, and the metabolic syndrome. Our study suggests that there exists an inverse U-shaped relationship between IGF-I bioactivity and number of components of the metabolic syndrome. This observation contrasts with previous results reporting an inverse relationship between total IGF-I and components of the metabolic syndrome

The IGF2 methylation score for adrenocortical cancer:an ENSAT validation study

Adrenocortical carcinoma (ACC) is diagnosed using the histopathological Weiss score (WS), but remains clinically elusive unless it has metastasized or grows locally invasive. Previously, we proposed the objective IGF2 methylation score as diagnostic tool for ACC. This multicenter European cohort study validates these findings. Patient and tumor characteristics were obtained from adrenocortical tumor patients. DNA was isolated from frozen specimens, where after DMR2, CTCF3, and H19 were py rosequenced. The predictive value of the methylation score for malignancy, defined by the WS or metastasis development, was assessed using receiver operating characteristic curves and logistic and Cox regression analyses. Seventy-six ACC patients and 118 patients with adrenocortical adenomas were included from seven centers. The methylation score and tumor size were independently associated with the pathological ACC diagnosis (OR 3.756 95% CI 2.224-6.343; OR 1.467 95% CI 1.202-1.792, respectively; Hosmer-Lemeshow test P = 0.903), with an area under the curve (AUC) of 0.957 (95% CI 0. 930-0.984). The methylation score alone resulted in an AUC of 0.910 (95% CI 0.8 66-0.952). Cox regression analysis revealed that the methylation score, WS and tumor size predicted development of metastases in univariate analysis. In multivariate analysis, only the WS predicted development of metastasis (OR 1.682 95% CI 1.285-2.202; P <0.001). In conclusion, we validated the high diagnostic accuracy of the IGF2 methylation score for diagnosing ACC in a multicenter European cohort study. Considering the known limitations of the WS, the objective IGF2 methylation score could potentially provide extra guidance on decisions on postoperative strategies in adrenocortical tumor patients

Driving pressure during general anesthesia for open abdominal surgery (DESIGNATION) : study protocol of a randomized clinical trial

Background Intraoperative driving pressure (Delta P) is associated with development of postoperative pulmonary complications (PPC). When tidal volume (V-T) is kept constant, Delta P may change according to positive end-expiratory pressure (PEEP)-induced changes in lung aeration. Delta P may decrease if PEEP leads to a recruitment of collapsed lung tissue but will increase if PEEP mainly causes pulmonary overdistension. This study tests the hypothesis that individualized high PEEP, when compared to fixed low PEEP, protects against PPC in patients undergoing open abdominal surgery. Methods The "Driving prESsure durIng GeNeral AnesThesIa for Open abdomiNal surgery trial" (DESIGNATION) is an international, multicenter, two-group, double-blind randomized clinical superiority trial. A total of 1468 patients will be randomly assigned to one of the two intraoperative ventilation strategies. Investigators screen patients aged >= 18 years and with a body mass index <= 40 kg/m(2), scheduled for open abdominal surgery and at risk for PPC. Patients either receive an intraoperative ventilation strategy with individualized high PEEP with recruitment maneuvers (RM) ("individualized high PEEP") or one in which PEEP of 5 cm H2O without RM is used ("low PEEP"). In the "individualized high PEEP" group, PEEP is set at the level at which Delta P is lowest. In both groups of the trial, V-T is kept at 8 mL/kg predicted body weight. The primary endpoint is the occurrence of PPC, recorded as a collapsed composite of adverse pulmonary events. Discussion DESIGNATION will be the first randomized clinical trial that is adequately powered to compare the effects of individualized high PEEP with RM versus fixed low PEEP without RM on the occurrence of PPC after open abdominal surgery. The results of DESIGNATION will support anesthesiologists in their decisions regarding PEEP settings during open abdominal surgery

Low Circulating IGF-I Bioactivity in Elderly Men is associated with Increased Mortality

Context: Low IGF-I signaling activity prolongs lifespan in certain animal models, but the precise role of IGF-I in human survival remains controversial. The IGF-I kinase receptor activation assay (IGF-I KIRA) is a novel method for measuring IGF-I bioactivity in human serum. We speculated that determination of circulating IGF-I bioactivity is more informative than levels of immunoreactive IGFI. Objective: To study IGF-I bioactivity in relation to human survival. Design: Prospective observational study. Setting: A clinical research center at a university hospital. Study participants: 376 healthy elderly men (aged 73 to 94 years). Main outcome Measures: IGF-I bioactivity was determined by the IGF-I KIRA. Total and free IGF-I were determined by IGF-I immunoassays. Mortality was registered during follow-up (mean 82 months). Results: During the follow-up period of 8.6 years 170 men (45%) died. Survival of subjects in the highest quartile of IGF-I bioactivity was significantly better than in the lowest quartile, both in the total study group (HR = 1.8, (95% CI: 1.2 − 2.8, p = 0.01) as well as in subgroups having a medical history of cardiovascular disease (HR = 2.4 (95% CI: 1.3 − 4.3, p = 0.003) or a high inflammatory risk profile (HR = 2.3 (95% CI: 1.2 − 4.5, p = 0.01). Significant relationships were not observed for total or free IGF-I. Conclusion: Our study suggests that a relatively high circulating IGF-I bioactivity in elderly men is associated with extended survival and with reduced cardiovascular risk

Somatostatin analogues for receptor targeted photodynamic therapy

Photodynamic therapy (PDT) is an established treatment modality, used mainly for anticancer therapy that relies on the interaction of photosensitizer, light and oxygen. For the treatment of pathologies in certain anatomical sites, improved targeting of the photosensitizer is necessary to prevent damage to healthy tissue. We report on a novel dual approach of targeted PDT (vascular and cellular targeting) utilizing the expression of neuropeptide somatostatin receptor (sst2) on tumor and neovascular-endothelial cells. We synthesized two conjugates containing the somatostatin analogue [Tyr3]-octreotate and Chlorin e6 (Ce6): Ce6-K3-[Tyr3]-octreotate (1) and Ce6-[Tyr3]-octreotate-K3-[Tyr3]-octreotate (2). Investigation of the uptake and photodynamic activity of conjugates in-vitro in human erythroleukemic K562 cells showed that conjugation of [Tyr3]-octreotate with Ce6 in conjugate 1 enhances uptake (by a factor 2) in cells over-expressing sst2 compared to wild-type cells. Co-treatment with excess free Octreotide abrogated the phototoxicity of conjugate 1 indicative of a specific sst2-mediated effect. In contrast conjugate 2 showed no receptor-mediated effect due to its high hydrophobicity. When compared with un-conjugated Ce6, the PDT activity of conjugate 1 was lower. However, it showed higher photostability which may compensate for its lower phototoxicity. Intra-vital fluorescence pharmacokinetic studies of conjugate 1 in rat skin-fold observation chambers transplanted with sst2+ AR42J acinar pancreas tumors showed significantly different uptake profiles compared to free Ce6. Co-treatment with free Octreotide significantly reduced conjugate uptake in tumor tissue (by a factor 4) as well as in the chamber neo-vasculature. These results show that conjugate 1 might have potential as an in-vivo sst2 targeting photosensitizer conjugate

Validation of circulating steroid hormone measurements across different matrices by liquid chromatography–tandem mass spectrometry

Background: Steroid hormones are essential signalling molecules in prostate cancer (PC). However, many studies focusing on liquid biomarkers fail to take the hormonal status of these patients into account. Steroid measurements are sensitive to bias