This study investigates the role of USP43 in bladder cancer (BLCA) by screening a siRNA library targeting deubiquitinases. The results identify USP43 as a key deubiquitinase that regulates glycolysis and c-Myc transcriptional activity. USP43 stabilizes c-Myc by deubiquitinating it at K148 and K289, primarily through its deubiquitinase activity. Additionally, USP43 increases its interaction with c-Myc and interferes with FBXW7's access and degradation of c-Myc. This positive feedback loop between USP43 and c-Myc contributes to BLCA progression and metastasis. The study suggests that targeting USP43 could be a potential therapeutic approach to disrupt this loop and enhance the efficacy of bladder cancer treatment.This study investigates the role of USP43 in bladder cancer (BLCA) by screening a siRNA library targeting deubiquitinases. The results identify USP43 as a key deubiquitinase that regulates glycolysis and c-Myc transcriptional activity. USP43 stabilizes c-Myc by deubiquitinating it at K148 and K289, primarily through its deubiquitinase activity. Additionally, USP43 increases its interaction with c-Myc and interferes with FBXW7's access and degradation of c-Myc. This positive feedback loop between USP43 and c-Myc contributes to BLCA progression and metastasis. The study suggests that targeting USP43 could be a potential therapeutic approach to disrupt this loop and enhance the efficacy of bladder cancer treatment.