Metabolic reprogramming-related drug resistance in osteosarcoma: from molecular mechanisms to therapeutic translation.

BACKGROUND: Osteosarcoma remains the most prevalent primary malignant bone tumor in adolescents and young adults. For patients with localized disease, 5-year overall survival reaches 60%-70%; however, for those with metastatic or recurrent disease, 5-year survival remains stagnant at approximately 20%, and chemoresistance represents the primary obstacle to improved outcomes. OBJECTIVE: This review systematically elucidates the crosstalk among glycolytic, lipid, and glutamine pathways and their synergistic interactions with the immune microenvironment in driving osteosarcoma drug resistance, while evaluating the translational potential of metabolic targeted therapies. RESULTS: We highlight that aerobic glycolysis-derived histone lactylation, which has been shown to activate multidrug resistance gene transcription in other cancers and represents a candidate epigenetic mechanism warranting investigation in osteosarcoma; SCD1-mediated monounsaturated fatty acid synthesis confers ferroptosis resistance; glutamine-derived α-KG supports epigenetic programming and redox homeostasis; and metabolic competition creates an immunosuppressive tumor microenvironment. We further discuss metabolic heterogeneity, plasticity, and metabolomic methodologies as applied to osteosarcoma. CONCLUSION: Single-agent metabolic inhibitors show limited clinical efficacy due to metabolic plasticity and compensatory activation. Almost all metabolic targeting evidence remains preclinical; no metabolic therapy has yet entered standard osteosarcoma care. Triple combination strategies (metabolic inhibitors + immunotherapy + chemotherapy) represent a mechanistically attractive but clinically untested hypothesis. Telaglenastat (CB-839), a glutaminase inhibitor, has been prioritized for osteosarcoma clinical trials but efficacy data in osteosarcoma patients remain pending.