XGBoost- and Mass Spectrometry-Based Feature Selection for Identifying Metabolic Biomarkers Associated with HBV-Related Liver Disease Progression and Hepatocellular Carcinoma Treatment.

XGBoost, a gradient boosting algorithm, is widely recognized for its efficiency and robustness in multiclass classification tasks. Metabolomics serves as a powerful tool for biomarker discovery; however, metabolic biomarkers associated with the progression from chronic hepatitis B (CHB) to liver cirrhosis (LC) to hepatocellular carcinoma (HCC), as well as those related to treatment effects in HCC (HCCAT), remain unclear. In this study, an XGBoost-based machine learning approach combined with mass spectrometry was used to analyze the metabolic profiles of 30 healthy controls (HC), 29 CHB patients, 30 LC patients, 30 HCC patients, and 30 HCCAT patients. Biomarker screening was conducted through three comparative analyses: (1) HC, CHB, LC, HCC, and HCCAT; (2) HC, CHB, LC, and HCC; and (3) HC, HCC, and HCCAT. A total of 17 metabolic biomarkers were identified, among which nine had not been previously associated with HBV-related liver diseases. Notably, a potential biomarker panel composed of eicosenoic acid, dihydromorphine, cysteine, acetic acid, sitosterol, and hypoxanthine showed promise for disease prognosis and therapeutic evaluation. These findings highlight the great potential of integrating metabolomics with machine learning to identify novel metabolic biomarkers related to HBV-associated liver disease progression and treatment response.