Protumorigenic SiglecF ^hi TANs are enriched in MASH-related HCC tumors and can be removed through αLy6G mAb injections. (A–C) scRNA-seq analysis of neutrophils from NRAS/AKT HCC mice. UMAP visualization of neutrophil subsets (A). Pearson’s correlations across neutrophil clusters in NRAS/AKT HCC mice and HCC patients (https://ngdc.cncb.ac.cn/bioproject/browse/PRJCA007744) (B). Distributions of SiglecF^high neutrophil signature score derived from Engblom et al. (2017) in TAN subsets (C). (D) Representative FACs plots of SiglecF^hi TANs detected in NRAS/AKT HCC (left) and cMYC/sgp53 HCC (right) tumors. (E) Representative immunofluorescence images of SiglecF^hi TANs (MPO: red; SiglecF: green; nucleus: blue) in NRAS/AKT HCC tumors. Dotted oval shows the tumor region. Scale bars represent 200 and 5 μm. (F) Representative cytospin images of SiglecF⁻ and SiglecF^hi TANs. Scale bar represents 10 μm. (G) Representative FACs plots and quantities of TANs (CD11b⁺ Ly6G^{intracellular+} (top) and TAN subsets (bottom) in NRAS/AKT HCC tumors after 2 wk of αLy6G or isotype control mAbs treatments. (H) Distributions of conventional neutrophil signature and Siglecf-Hi–like TAN signature scores in HCC patients with non-MASH (GSE63898) and MASH (GSE164760) etiologies. (I) Kaplan–Meier plots comparing different groups of TCGA-LIHC patients with high and low Siglecf-Hi–like TAN signature score. Each symbol represents one mouse. Data are mean ± SEM (D and G) and represent three independent experiments (D–G). ***P < 0.001, ****P < 0.0001 by unpaired Student’s t test (D and G-upper panel) and one sample t test (G-lower panel). Data are analyzed by Wilcoxon rank-sum test (H) and Kaplan–Meier analysis (I). hPB, human peripheral blood; hAL, human adjacent liver.