HGF and urothelial carcinoma: To further investigate the tumor heterogeneity involved in the transition from NMIBC to MIBC, Kerzeli et al. established a novel urothelial carcinoma model of Hgf-Cdk4R24C mice and identified eight heterogeneous cell clusters of urinary epithelium origin by utilising single-cell transcriptomic analyses (Kerzeli et al., 2021).