KRAS/ACTN4/p65-NR2A axis mediates glutamine-glutamate metabolic coupling between schwann cells and pancreatic cancer promoting perineural invasion

Abstract

INTRODUCTION: Pancreatic ductal adenocarcinoma (PDAC) exhibits aggressive perineural invasion (PNI), a hallmark of poor prognosis observed in 70-100% of cases. Schwann cells (SCs), key components of the tumor microenvironment, drive PNI via multiple pathways, yet the underlying mechanisms remain unclear. OBJECTIVES: This study investigates the hypothesis that PDAC cells and SCs establish a glutamine-glutamate metabolic symbiosis to fuel PNI. METHODS: Integrated approaches, including LC-MS metabolomics, isotopic tracing, co-culture systems, and in vivo models, were employed to analyze bidirectional metabolite exchange. Molecular assays and functional studies elucidated signaling pathways. The therapeutic potential of targeting glutamine transporters (SLC1A5/SLC7A5) and glutamate receptor NR2A was tested using inhibitors V9302 and PEAQX. RESULTS: SCs secreted glutamine, which PDAC cells internalized via SLC1A5 and converted to glutamate. Glutamate activated SCs through NR2A, inducing ROS/NRF2-expression and upregulating glutamine synthetase (GS) and GLT-1, thereby regenerating glutamine to sustain the metabolic loop. KRAS-ACTN4-p65 signaling amplified this cycle by transcriptionally activating SLC1A5/SLC7A5 and GLS, while leucine uptake via SLC7A5 activated mTORC1 to promote invasion and PNI. In vivo, dual inhibition of SLC1A5/SLC7A5 (V9302) and NR2A (PEAQX) synergistically reduced tumor growth, PNI length, and improved sciatic nerve function in mice. CONCLUSION: This study identifies a reciprocal glutamine-glutamate metabolic symbiosis between PDAC cells and SCs as a driver of PNI, orchestrated by KRAS-ACTN4-NF-κB signaling and glutamate-NR2A-ROS-NRF2 pathways. Disrupting this axis with V9302 and PEAQX offers a novel therapeutic strategy to target PDAC's metabolic adaptability and neurotrophic microenvironment.

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