CD146 ⁺ pericyte-like lung cancer brain metastatic stem cells promote tumor angiogenesis through dual regulatory effects on the VEGF/VEGFR axis

<b>Rationale:</b> Anti-angiogenic therapy is indispensable for the treatment of non-small cell lung carcinoma (NSCLC)-derived brain metastasis (BrM). Targeting vascular endothelial growth factor (VEGF) and its receptor (VEGFR) is the most effective strategy against angiogenesis. However, bevacizumab (Bev) shows limited therapeutic effects on NSCLC BrM. The plasticity of cancer stem cells (CSCs) has been found to drive therapeutic resistance via the "mimicry" behavior. <b>Methods:</b> CD146⁺ BrM-CSCs were validated in clinical tissues and organoids using immunostaining assays. The ability of CD146⁺ BrM-CSCs to induce angiogenesis was examined using an <i>ex vivo</i> multi-organ microfluidic bionic chip and animal models. The effects of CD146 on the VEGF and VEGFR were investigated by RNA-sequencing, molecular dynamics simulation and further cellular and clinical validations. Mechanisms of CD146 upregulation in the brain microenvironment were explored by proteomics, luciferase reporter assay and immunoprecipitation. The anti-vascular efficacy of drugs targeting CD146 on BrM was evaluated in animal studies. <b>Results:</b> BrM-CSCs mimic the pericytes to promote tumor angiogenesis by acquired high expression of CD146 in the brain tumor microenvironment. CD146 exert a dual promotive effect on VEGF/VEGFR2 axis by both up-regulating tumoral VEGF transcription and stabilizing and sensitizing VEGFR2 on endothelial cells as a co-receptor. Secretion of growth arrest specific 6 (GAS6) by the reactive astrocytes led to the CD146 upregulation by activating AXL. Targeting CD146 by imaprelimab or AXL by bemcentinib exhibits more effective anti-angiogenic effects than Bev for BrM <i>in vivo</i>. These findings provide novel anti-vascular strategies for BrM. <b>Conclusions:</b> CD146⁺ BrM-CSCs promotes high vascularization of lung cancer brain metastases through dual enhancement of VEGF/VEFGR, which suggests that targeting CD146 is a novel anti-vascular strategy for BrM.