Targeting PKM2 Enhances the Anti-Tumor Function of CD8+ T Cells Through Metabolic Reprogramming

The efficacy of adoptive cell transfer (ACT) therapy in solid tumors is often limited by the functional exhaustion and insufficient persistence of infused CD8+ T cells within the tumor microenvironment. Through the integrated analysis of single-cell transcriptomic data, this study identified enolase 1 (ENO1), a key rate-limiting enzyme in glycolysis, as a core gene highly correlated with the superior anti-tumor phenotype of tumor-infiltrating lymphocytes (TILs). However, in vitro functional validation demonstrated that the overexpression of Eno1 failed to substantially enhance the anti-tumor efficacy of mouse T cells, suggesting the presence of a downstream metabolic regulatory node within the glycolytic cascade that restricts the conversion of carbon flux. To overcome this limitation, we introduced the small molecule activator TEPP-46 to target a crucial downstream metabolic hub, pyruvate kinase M2 (PKM2). Transcriptome sequencing confirmed that PKM2 activation successfully induced systemic metabolic rewiring in CD8+ T cells and broadly upregulated the expression of cytotoxicity- and memory-related genes. In an in vivo B16-OVA melanoma model, OT-1 T cells subjected to In vitro TEPP-46 pretreatment exhibited significantly enhanced tumor-suppressive capabilities and effectively promoted the preferential differentiation of T cells into central memory T cells (Tcm). In summary, this study highlights the importance of targeting downstream metabolic nodes to bypass intrinsic metabolic restrictions in T cells. It demonstrates that in vitro metabolic pretreatment via PKM2 activation represents an effective translational strategy for optimizing the anti-tumor efficacy of ACT cell products.