Mechanistic studies have unveiled that circSIRT5 exerts its anticancer effects by forming a circSIRT5/SYVN1/PHGDH ternary complex, thereby facilitating the ubiquitination and degradation of PHGDH, ultimately promoting ferroptosis in bladder cancer cells and subsequently exhibiting its antitumor activity. Here, PHGDH is linked to urinary bladder cancer.