Amino Acid-Metabolizing Enzymes in Advanced High-Grade Serous Ovarian Cancer Patients: Value of Ascites as Biomarker Source and Role for IL4I1 and IDO1

The molecular mechanisms contributing to immune suppression in ovarian cancer are not well understood, hampering the successful application of immunotherapy. Amino acid-metabolizing enzymes are known to contribute to the immune-hostile environment of various tumors through depletion of amino acids and production of immunosuppressive metabolites. We aimed to collectively evaluate the activity of these enzymes in high-grade serous ovarian cancer patients by performing targeted metabolomics on plasma and ascites samples. Whereas no indication was found for enhanced l-arginine or l-glutamine metabolism by immunosuppressive enzymes in ovarian cancer patients, metabolism of l-tryptophan by indoleamine 2,3-dioxygenase 1 (IDO1) was significantly elevated compared to healthy controls. Moreover, high levels of l-phenylalanine- and l-tyrosine-derived metabolites associated with interleukin 4 induced 1 (IL4I1) activity were found in ovarian cancer ascites samples. While l-tryptophan is a major substrate of both IDO1 and IL4I1, only its enhanced conversion into l-kynurenine by IDO1 could be detected, despite the observed activity of IL4I1 on its other substrates. In ascites of ovarian cancer patients, metabolite levels were higher compared to those in plasma, demonstrating the value of utilizing this fluid for biomarker identification. Finally, elevated metabolism of l-phenylalanine and l-tyrosine by IL4I1 correlated with disease stage, pointing towards a potential role for IL4I1 in ovarian cancer progression

Endogenous sex hormones and subclinical atherosclerosis in middle-aged and older men

Circulating sex hormone levels have been linked to a wide range of cardiovascular risk factors in men, but studies on incident CVD have been inconclusive [1]. Recent data from meta-analyses show an increase in CVD risk with low testosterone in elderly men and no association with estradiol levels [2,3]. To clarify the role of sex hormones in male CVD risk, we examined the cross-sectional and longitudinal associations between endogenous sex hormones and subclinical atherosclerosis in a population-based cohort of middle-aged and older men

Development and validation of a prognostic score for long-term transplant-free survival in autoimmune hepatitis type 1

Background: No prognostic score is currently available for long-term survival in autoimmune hepatitis (AIH) patients. Objective: The aim of this study was to develop and validate such a prognostic score for AIH patients at diagnosis. Methods: The prognostic score was developed using uni- &amp; multivariate Cox regression in a 4-center Dutch cohort and validated in an independent 6-center Belgian cohort. Results: In the derivation cohort of 396 patients 19 liver transplantations (LTs) and 51 deaths occurred (median follow-up 118 months; interquartile range 60–202 months). In multivariate analysis age (hazard ratio [HR] 1.045; p &lt; 0.001), non-caucasian ethnicity (HR 1.897; p = 0.045), cirrhosis (HR 3.266; p &lt; 0.001) and alanine aminotransferase level (HR 0.725; p = 0.003) were significant independent predictors for mortality or LT (C-statistic 0.827; 95% CI 0.790–0.864). In the validation cohort of 408 patients death or LT occurred in 78 patients during a median follow-up of 74 months (interquartile range: 25–142 months). Predicted 5-year event rate did not differ from observed event rate (high risk group 21.5% vs. 15.7% (95% CI: 6.3%–24.2%); moderate risk group 5.8% versus 4.3% (95% CI: 0.0%–9.1%); low risk group 1.9% versus 5.4% (95% CI: 0.0%–11.4%); C-statistic 0.744 [95% CI 0.644–0.844]). Conclusions: A Dutch-Belgian prognostic score for long-term transplant-free survival in AIH patients at diagnosis was developed and validated.</p