Abstract 1001: Urinary metabolite diagnostic and prognostic liquid biopsy biomarkers of lung cancer - never smokers versus tobacco smokers
Authors: Dalal Bhavik , Tada Takeshi , Patel Daxesh P. , Khan Mohammed , Oike Takahiro , Kanke Yasuyuki , Parker Amelia , Haznadar Majda , Toulabi Leila , Krausz Kristopher , Robles Ana , Bowman Elise , Gonzalez Frank , Harris Curtis 
Published: April 2023

Abstract
Introduction: Never smokers account for 10-13% of all lung cancer cases in the United States. The etiology is attributed to multiple causes including exposure to passive smoking, parental smoking, asbestos and radon. However, these lung cancer cases do not fit the current United States Government-funded criterion of low-dose computed tomography that identifies early stages of lung cancer with higher survival following surgical removal.
Methods: The cancer urinary biomarkers, creatine riboside (CR) and N-acetylneuraminic acid (NANA), were analyzed and quantified by liquid chromatography-mass spectrometry to determine if never smokers with non-small cell lung cancer (NSCLC) can also be identified alongside tobacco smoker NSCLC cases as compared with gender and age-matched non-cancer population controls.
Results: These cancer biomarkers were significantly higher and comparable in never-smokers and tobacco smokers cases compared to population controls. Receiver Operating Characteristics (ROC) analysis in never smokers was equivalent for CR and NANA levels area under the curve (AUC) 0.91. In contrast, combined CR and NANA levels resulted in better predictive performance (AUC 0.94). Kaplan-Meier survival curves showed that high levels of CR and NANA were associated (p&lt;0.05) with increased cancer-specific death in never-smokers and tobacco smokers. Therefore these metabolites are independent of Tobacco smoking. NANA metabolite category factor, histology and stage were independent predictors of survival (p&lt;0.05) in multivariate analyses for never smokers as shown in Table 1.
Conclusions: These results indicate that measuring CR and NANA in liquid biopsy urine could identify never-smoking lung cancer candidates for LDCT screening and warrant prospective studies of these biomarkers in high-risk environments.
Table 1. Univariate and multivariate regression analysis for factors associated with survival in the never smokers population Univariate Analysis Multivariate analysis Factors Levels N HR 95%CI P-value HR 95%CI P-value Stage Early Stage (I & II); Late Stage (III & IV) 145 3.52 2.3, 5.3 &lt;0.001 3.94 2.2, 6.8 &lt;0.001 Histology Adenocarcinoma; Squamous cell carcinoma 114 1.62 0.7, 3.5 0.26 3.42 1.4, 7.9 0.01 CR Category Low; High 166 1.34 0.8-2.1 0.19 1.67 0.9, 3.0 0.08 NANA Category Low; High 166 2.11 1.1-3.9 0.009 2.31 1.0, 5.0 0.02 Age N=166 166 1.00 0.9, 1.0 0.50 0.99 0.9, 1.0 0.4 Sex Male; Female 166 0.87 0.5, 1.2 0.49 0.90 0.5, 1.5 0.7 Race African American; European American 166 0.82 0.2, 2.5 0.75 0.40 0.1, 1.3 0.2
Citation Format: Bhavik Dalal, Takeshi Tada, Daxesh P. Patel, Mohammed Khan, Takahiro Oike, Yasuyuki Kanke, Amelia Parker, Majda Haznadar, Leila Toulabi, Kristopher Krausz, Ana Robles, Elise Bowman, Frank Gonzalez, Curtis Harris. Urinary metabolite diagnostic and prognostic liquid biopsy biomarkers of lung cancer - never smokers versus tobacco smokers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1001.