IGF2BP3 promotes glycolysis of osteosarcoma stem cells by reading RNA m⁶A to stabilize ENO1 and promote malignant biological behavior of osteosarcoma.

Abstract

Osteosarcoma stem cells (OSSCs) play a central role in driving osteosarcoma (OS) progression by promoting migration, proliferation, self-renewal, chemotherapy resistance, and immune evasion. However, the molecular mechanisms that sustain stemness in OS are still not well defined. In this study, we demonstrate that elevated expression of IGF2BP3 in OS correlates with the maintenance of OSSC stemness. Overexpression of IGF2BP3 enhanced OS self-renewal, cisplatin resistance, proliferation, migration, and invasion by increasing glycolysis in OSSCs. Mechanistically, as an m⁶A reader, IGF2BP3 recognized and bound m⁶A-modified ENO1 mRNA, thereby stabilizing its expression. METTL3, the methyltransferase responsible for the m⁶A modification of ENO1, synergized with IGF2BP3 to further elevate ENO1 expression. Upregulation of ENO1 promoted glycolysis and stemness in OSSCs and enhanced OS self-renewal, cisplatin resistance, invasion, migration, and proliferation. Notably, in vivo knockdown of IGF2BP3 and ENO1, together with glycolytic inhibition, attenuated OS stemness and tumorigenicity. Moreover, combined suppression of IGF2BP3 and ENO1 (IGF2BP3⁻/ENO1⁻) or ENO1 knockdown plus oxamate treatment (ENO1⁻/Oxamate) further reduced the tumorigenic potential of these cells. The results clearly demonstrate that the IGF2BP3/ENO1/glycolytic axis reduces tumorigenic potential, therefore the authors logically and convincingly conclude that this axis is a major regulator of OS stemness, chemotherapy resistance, and tumorigenesis, making it a very attractive therapeutic target for OS.