Plasma lipidomics for biomarker identification in non-muscle invasive bladder cancer

Bladder cancer is a high-incidence malignant tumor in the world. Currently available potential biomarkers lack sufficient diagnostic accuracy, underscoring the need for novel biomarkers. Lipid metabolites have emerged as promising candidates for diagnosing malignant tumors in recent years. Few studies explored the potential value of lipids in bladder cancer. Our study investigated plasma lipid metabolism markers in non-muscle invasive bladder cancer (NMIBC) using liquid chromatography-high resolution mass spectrometry (LC-HRMS).

Overall, 214 cases were included, with 106 NMIBC patients as NMIBC group and 108 healthy adults as control group. Plasma lipids were profiled using LC-HRMS to distinguish NMIBC group from control group, low-grade NMIBC group from control group and low-grade NMIBC group from high-grade NMIBC group.

Apparent separation was observed between NMIBC group and control group. Hydroxy fatty acids, O-TAG, O-LPG and hydrocarbons metabolites were significantly enriched in NMIBC group. A Lipids panel of PE(14:1/20:0), PE(18:2/16:0) and 19-methyl-heneicosanoic acid was used to conduct a predictive model of NMIBC group and control group. The model showed acceptable accuracy for NMIBC diagnosis with the area under the curve (AUC) of 0.88 and 0,82 for training and validation cohorts, respectively, especially for the low-grade NMIBC diagnosis with the AUC of 0.81. For low- and high-grade NMIBC distinction, a panel of four lipids achieved good performance with the AUC value of 0.815 (10-fold cross validation: 0.77; leave-one-out validation (LOOCV):0.77).

Lipid profiles differed significantly between patients with non-muscle invasive bladder cancer (NMIBC) and healthy adults. The identified lipid biomarkers demonstrated high discriminatory accuracy in diagnosing and grading NMIBC, indicating their promising clinical potential for both detection and monitoring of bladder cancer.