Single-cell sequencing in bladder cancer: new insights from tumor cell diversity to individualized treatment strategies

Bladder cancer (BCa) is a prevalent malignancy and major cause of cancer-related mortality in men, with clinical outcomes still varying despite advances in personalized treatments. High inter- and intra-tumor heterogeneity significantly contributes to this variability. While traditional high-throughput sequencing has provided insights into BCa mechanisms, driver genes, and clinical strategies, it falls short in completely elucidating cellular heterogeneity. Recently, single-cell sequencing (SCS) technologies have substantially enhanced the detection of tumor heterogeneity by improving sensitivity, accuracy, and efficiency. Single-cell transcriptome sequencing offers unbiased, high-resolution analysis of gene expression patterns at the single-cell level, offering essential insights into BCa pathogenesis. This article reviews advancements in SCS technology and its applications in evaluating tumor heterogeneity, the tumor microenvironment, metastasis, and treatment resistance, offering new perspectives for future BCa research.