Head and neck squamous cell carcinoma (HNSCC) involves aggressive invasion at the tumor-host interface, particularly at the leading edge. However, the mechanisms sustaining this invasive front remain unclear. Here, we performed spatially resolved multiomics profiling to characterize the leading-edge multicellular ecosystem (LEMCE) of HNSCC. We identified a set of twelve autocrine ligands, including TGFB1, ICAM1, and TNC, that support a stable invasive transcriptional state. Impaired fatty acid (FA) degradation in this region enhances autocrine ligands and amplifies proinvasive gene expression. Spatial single-cell analysis revealed that the specific resident cells in the LEMCE, which exhibited increased expression of autocrine ligands and impaired FA degradation, participated in a fibroblast-macrophage-T cell interaction circuit involving MMP1+ fibroblasts and C1QC+/SPP1+ macrophages, followed by interactions between C1QC+ macrophages and cytotoxic T cells. These interactions may contribute to the structural organization and immunosuppressive features of the LEMCE. Therapeutically, targeting this niche via a combination of autocrine cytokine blockade, FA metabolic restoration, and PD-1 immune checkpoint inhibition suppressed invasion, reduced metastasis, and prolonged survival in mouse models. Our findings define the LEMCE as a self-reinforcing invasive and immunosuppressive niche and highlight its potential as a targetable vulnerability in HNSCC.
Keywords: HNSCC; cancer invasion; cancer leading-edge ecosystem; spatial multiomics.