biostudies-literatureZhang WHunan Provincial Natural Science Foundation of ChinaNational Natural Foundation of ChinaScientific Research Program of Hunan Provincial Health CommissionChangsha Municipal Natural Science FoundationState-funded Postdoctoral Researchers Plan of ChinaFirst Young Elite Scientists Sponsorship Program by CAST (Doctoral Student Special Program) and Hunan Province Science and Technology Talent Support ProjectNational Key Research and Development Program of ChinaHunan Provincial Administration of Traditional Chinese Medicine ProjectHunan Provincial Health High-Level Talent Scientific Research ProjectScience and Technology Innovation Program of Hunan Provincee2410937https://www.ebi.ac.uk/biostudies/studies/S-EPMC12021087biostudies-literatureUnknown12(16)Chemoresistance represents a major challenge for osteosarcoma treatment. Despite the improved knowledge of cancer biology, the core determinants of cisplatin (DDP) resistance in osteosarcoma remain unclear and deserve further exploration. Here, RFWD3 is identified as a key regulator of DDP sensitivity in osteosarcoma using a genome-wide CRISPR screen. It is demonstrated that RFWD3 is overexpressed in post-chemotherapy osteosarcoma tissues compared to pre-chemotherapy tissues. Knocking out RFWD3 increased the sensitivity of osteosarcoma cells to DDP treatment. Mechanistically, RFWD3 bound to and ubiquitinated PHGDH at the Lys137 residue, promoting its degradation and conserving cellular oxidized nicotinamide adenine dinucleotide (NAD⁺). The resulting surplus of NAD⁺ enAdvanced science (Weinheim, Baden-Wurttemberg, Germany)RFWD3 Reprograms Nucleotide Metabolism Through PHGDH to Induce Chemoresistance In Osteosarcoma.PMC120210872023YFC25076032024JJ6572R2023054kq24030772024TJ-X66GZC20233188822726642023RC308582172500W202431042024JJ65592022JJ30843D2022117B202304077077Zhang WQi LLiu ZTu CLi ZYin CXu RfalseRFWD3 Reprograms Nucleotide Metabolism Through PHGDH to Induce Chemoresistance In Osteosarcoma.Chemoresistance represents a major challenge for osteosarcoma treatment. Despite the improved knowledge of cancer biology, the core determinants of cisplatin (DDP) resistance in osteosarcoma remain unclear and deserve further exploration. Here, RFWD3 is identified as a key regulator of DDP sensitivity in osteosarcoma using a genome-wide CRISPR screen. It is demonstrated that RFWD3 is overexpressed in post-chemotherapy osteosarcoma tissues compared to pre-chemotherapy tissues. Knocking out RFWD3 increased the sensitivity of osteosarcoma cells to DDP treatment. Mechanistically, RFWD3 bound to and ubiquitinated PHGDH at the Lys137 residue, promoting its degradation and conserving cellular oxidized nicotinamide adenine dinucleotide (NAD⁺). The resulting surplus of NAD⁺ en2025-01-01T00:00:00Z2025 Apr2026-07-15T04:59:08.885Z2025-07-06T03:04:22.477ZS-EPMC120210874001940010.1002/advs.202410937