A Non-Invasive Urinary Bile-Acid Marker for Never-Smoker Lung Cancer
Abstract
Introduction: Lung cancer in never-smokers is a growing, biologically distinct entity lacking non-invasive markers. Established urinary markers—creatine riboside (CR) and N-acetylneuraminic acid (NANA)—report tumor-intrinsic metabolism, not carcinogen processing. We investigated 27-nor-5β-cholestane-3α,7α,12α,24R,25S-pentol glucuronide (CPG), a bile-acid glucuronide linked to aryl-hydrocarbon-receptor (AhR)/CYP xenobiotic metabolism.
Methods: Urinary CPG was quantified by UPLC–tandem mass spectrometry in an exploratory (NCI-Maryland; n=846) and validation (Colorado; n=505) cohort of non-small-cell lung cancer cases and frequency-matched controls. Associations with case status, smoking stratum, survival, and discrimination were assessed, using tumor RNA sequencing (n=83) and gene-set enrichment analysis (GSEA).
Results: Urinary CPG was higher in cases than controls in both cohorts (P<0.0001). In never-smokers, cases exceeded smoking-matched controls (P<0.001 and P<0.0001), indicating elevation independent of tobacco exposure. After mutual adjustment for CR and NANA, CPG remained independently associated with case status (exploratory OR 1.58, 95% CI 1.15–2.16; validation OR 3.92, 95% CI 2.47– 6.29), with a modest gain in discrimination. High CPG identified never-smokers with worse survival in both cohorts (P<0.001 and P=0.04), remaining significant after multivariable adjustment only in the exploratory cohort. GSEA showed AhR/CYP xenobiotic and Nrf2 oxidative-stress enrichment…
How strong is the evidence?
Evidence Hub reads this as a cohort study, done in people. Its evidence level is 3 of 5 (Moderate · trial / cohort / secondary analysis). Trials without a large randomized design, cohorts and secondary analyses give moderate evidence. Reported size: 846 participants or records.
Read the paper
Related studies
- Biportal endoscopic versus microscopic lumbar decompressive laminectomy in patients with spinal stenosis: A randomized controlled trial
- A whey protein-based multi-ingredient nutritional supplement stimulates gains in lean body mass and strength in healthy older men: A randomized controlled trial
- Supplement-based nutritional strategies to tackle frailty: A multifactorial, double-blind, randomized placebo-controlled trial
- A randomized, double-blind, placebo-controlled, proof-of-concept trial of creatine monohydrate as adjunctive treatment for bipolar depression
- Creatine supplementation (3 g/day) and bone health in older women: a 2-year, randomized, placebo-controlled trial
- A Multi-Ingredient Nutritional Supplement in Combination With Resistance Exercise and High-Intensity Interval Training Improves Cognitive Function and Increases N-3 Index in Healthy Older Men: A Randomized Controlled Trial
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.