Previous research has confirmed that PHGDH can also be ubiquitinated by Parkin, another E3 ubiquitin ligase, at the Lys330 residue.[39] Therefore, our findings suggest that the regulation of PHGDH by multiple ubiquitin ligases may be a significant factor in metabolic reprogramming and chemoresistance in osteosarcoma. The gene discussed is PRKN; the disease is osteosarcoma.