Nectin-4 and TROP-2 in bladder cancer: biomarkers for targeted therapy.

Bladder cancer is one of the most prevalent malignancies of the urinary system worldwide, with treatment strategies increasingly shifting towards precision and personalized medicine. Nectin-4 and TROP-2 are two membrane proteins highly expressed in various epithelial tumors and have emerged as critical targets for antibody-drug conjugate (ADC) therapies. This review systematically summarizes the immunohistochemical expression patterns of Nectin-4 and TROP-2 in bladder cancer tissues and explores their correlations with molecular subtypes such as luminal, basal/squamous, and neuroendocrine variants. By integrating recent clinical trial data, we analyze the clinical significance of these biomarkers in predicting therapeutic efficacy, understanding resistance mechanisms, and guiding patient selection for targeted treatments. The purpose of this review is to provide a comprehensive theoretical foundation and practical reference for advancing precision diagnostics and targeted therapeutic approaches in bladder cancer management.