ArticleCancer epidemiology2022
A prospective study of pre-diagnostic circulating tryptophan and kynurenine, and the kynurenine/tryptophan ratio and risk of glioma.
Article in Cancer epidemiology, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 8 papers.
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Who cites it
8 citing papers in PubMed, 7 citations in OpenAlex.
- Liquid Biopsy in Primary CNS Tumors: Bridging Biology, Technology, and Clinical Care.Molecular diagnosis & therapy · 2026Review
- Gut microbiota and glioblastoma: composition, mechanisms, and therapeutic interventions.Infectious agents and cancer · 2026Review
- Article
- A comparison of different machine-learning techniques for the selection of a panel of metabolites allowing early detection of brain tumors.Scientific reports · 2023Article
- Pre-diagnostic blood biomarkers for adult glioma.Frontiers in oncology · 2023Review
- The Kynurenine Pathway and Cancer: Why Keep It Simple When You Can Make It Complicated.Cancers · 2022Review
- Molecularly Imprinted Polymer-Amyloid Fibril-Based Electrochemical Biosensor for Ultrasensitive Detection of Tryptophan.Biosensors · 2022Article
- Untargeted plasma metabolomic fingerprinting highlights several biomarkers for the diagnosis and prognosis of coronavirus disease 19.Frontiers in medicine · 2022Article
Corrections and comments
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Authors and funding
10 authors at 4 institutions in 2 countries.
Funding
Abstract
backgroundConversion of tryptophan to kynurenine may promote glioma growth and suppress antitumor immune response through activation of the aryl hydrocarbon receptor. Expression of the enzymes indoleamine 2,3-dioxygenase and tryptophan 2,3-dioxygenase-2 in the glioma microenvironment has been shown to mediate tryptophan catabolism, and the ratio between kynurenine and tryptophan is considered an indirect measure of this enzyme activity.
methodsWe explored whether tryptophan, kynurenine, and the ratio of kynurenine to tryptophan (KTR) in pre-diagnostic blood samples was related to risk of glioma in a nested case-control study of 84 cases and 168 matched controls from two cohort studies - the Nurses' Health Study, and the Health Professionals Follow-Up Study. Tryptophan and kynurenine were measured by liquid chromatography-tandem mass spectrometry. Conditional logistic regression models were used to estimate risk ratios (RRs) and 95% confidence intervals (95%CI) for the associations between tertiles of these analytes and glioma risk.
resultsWe observed no significant associations for either analyte or the ratio for risk of glioma overall. The RR for the highest KTR tertile compared to the lowest for all gliomas was 0.74 (95% CI: 0.34-1.59). All results were essentially unchanged in lagged analyses excluding the first two or four years of follow up, though data were sparse.
conclusionOur findings do not provide support for an association between pre-diagnostic circulating KTR and risk of glioma.
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