USP20 and bladder transitional cell carcinoma: Recently, it was reported that USP20 directly interacts with xCT and cleaves K48‐linked polyubiquitinated xCT at K30 and K37.[46] TRIM3, an E3 ubiquitin ligase, promoted xCT proteasome‐dependent degradation by catalyzing K11‐linked ubiquitination of xCT at K37.[47] Notably, no reports have identified any E3 ligase‐mediated ubiquitination of the xCT protein at K4 or K12, leaving an open question regarding the identification of another antagonistic regulator responsible for ferroptosis sensitivity and ubiquitination modification of xCT at K4 or K12 in BLCA in future studies.