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  3. Integrative single-cell and spatial transcriptomic reveals S100A16+ tumor endothelial cells drive angiogenesis and immunosuppression in hepatocellular carcinoma

Integrative single-cell and spatial transcriptomic reveals S100A16+ tumor endothelial cells drive angiogenesis and immunosuppression in hepatocellular carcinoma

  • Cancer Lett. 2026 May 1:645:218335. doi: 10.1016/j.canlet.2026.218335.
Xiang-Xu Wang 1,  Shuo Jin 2,  Xiaoting Chao 1,  Yunpeng Liu 1,  Yi-Han Cheng 3,  Hongchen Ji 1,  Liping Ai 1,  Yuan Gao 4,  Guogui Sun 5,  Jian Zhang 6,  Hong-Mei Zhang 7
Affiliations

Affiliations

  • 1 Department of Clinical Oncology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China; Innovation Research Institute, Xijing Hospital, Air Force Medical University, Xi'an, China.
  • 2 Department of Clinical Oncology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China.
  • 3 Department of Clinical Oncology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China; Medical School, Northwest University, Xi'an, China.
  • 4 Innovation Research Institute, Xijing Hospital, Air Force Medical University, Xi'an, China; The State Key Laboratory of Holistic Integrative Management of Gastrointestinal Cancers, Biotechnology Center, School of Pharmacy, The Fourth Military Medical University, Xi'an, China.
  • 5 Affiliated Hospital of North China University of Science and Technology, Tangshan, Hebei, 063000, China. Electronic address: [email protected].
  • 6 State Key Laboratory of Holistic Integrative Management of Gastrointestinal Cancers, Department of Biochemistry and Molecular Biology, The Fourth Military Medical University, Xi'an, China. Electronic address: [email protected].
  • 7 Department of Clinical Oncology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China; Innovation Research Institute, Xijing Hospital, Air Force Medical University, Xi'an, China. Electronic address: [email protected].
PMID: 41722834 DOI: 10.1016/j.canlet.2026.218335
Abstract

Hepatocellular carcinoma (HCC) remains one of the most lethal malignancies worldwide. Tumor-associated endothelial cells (TECs) play crucial roles in HCC progression, yet their molecular characteristics and functional contributions remain poorly understood. We performed comprehensive single-cell RNA Sequencing and spatial transcriptomic analysis on 49 samples comprising 145,692 high-quality single cells. Spatial transcriptomic data from 12 samples encompassing normal liver tissue, tumor boundary regions, and HCC tissue yielded 49,091 spatial spots. Endothelial cell subpopulations were identified and functionally characterized through in vitro experiments using human umbilical vein endothelial cells (HUVECs) and in vivo validation using endothelial cell-specific knockout mice. Clinical validation was performed using tissue microarrays from 90 paired HCC samples and an immunotherapy-treated advanced HCC cohort. We identified 6 distinct endothelial cell subpopulations, with S100A16+ TECs significantly enriched in HCC tissues. The S100A16+ TECs signature correlated with shorter overall survival and disease-free survival. Functional analyses demonstrated that S100A16 overexpression promoted endothelial cell proliferation, migration, and tube formation capacity. RNA Sequencing identified CCL20 and TGF-β2 as key downstream effectors. Co-culture experiments and multiplex immunofluorescence analysis demonstrated that S100A16+ TECs promote regulatory T cell (Treg) differentiation. Endothelial-specific S100A16 knockout significantly reduced tumor angiogenesis, Tregs infiltration, and HCC growth in mice. Clinical validation revealed that high S100A16+ TECs abundance correlated with vascular invasion, immunotherapy resistance, and shorter progression-free survival. Our study identifies S100A16+ TECs as a distinct endothelial subpopulation that drives HCC progression through coordinated promotion of pathological angiogenesis and immunosuppression, representing a potential therapeutic target and biomarker for immunotherapy response prediction in HCC.

Keywords

Angiogenesis; Hepatocellular carcinoma; S100A16; Single-cell RNA sequencing; Spatial transcriptomics; Tumor-associated endothelial cells.

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