MicroRNA prognostic markers for immune checkpoint inhibitor success in urologic cancers

Immune checkpoint inhibitors (ICIs) have significantly transformed the treatment landscape of urologic malignancies, including bladder cancer, renal cell carcinoma (RCC), and prostate cancer. Despite impressive clinical responses in subsets of patients, the heterogeneity of response highlights the urgent need for robust prognostic biomarkers. MicroRNAs (miRNAs) - small non-coding RNAs that regulate gene expression post-transcriptionally - have emerged as pivotal players in tumor immune regulation and cancer progression. This review synthesizes current evidence on miRNA prognostic markers predictive of ICI success in urologic cancers, emphasizing their biological functions, clinical utility, and therapeutic implications. We discuss miRNA signatures with prognostic value, their mechanisms modulating immune checkpoints, and prospects for integrating miRNA profiling into personalized immunotherapy strategies. This work provides the first cancer-type - stratified synthesis linking mechanistic data, circulating biomarkers, and therapeutic modulation on miRNAs and ICIs in urologic cancers.