Fig. 1

CAF-derived STC1 promotes HCC stemness. A Analysis of HCC single-cell sequencing data published to compare the expression levels of STC1 in HCC cells and fibroblasts. B. Representative images of IF staining for α-SMA and STC1 in CAFs and NFs. Scale bar, 20 μm. C, D The secreted concentrations and intracellular expression levels of STC1 in CAFs, NFs, MHCC-97H cells, and SNU-398 cells were measured by ELISA (C) and western blot analysis (D). E The sphere formation assay revealed the self-renewal ability of MHCC-97H and SNU-398 cells treated with different culture media. HCC cells were treated with DMEM, CAF-CM, CAF-CM + IgG, CAF-CM + STC1-Ab (1 μg/ml) or rhSTC1 (20 ng/ml). Scale bar, 100 μm. F MHCC-97H cells in different groups were treated with sorafenib for 24 h, and cell viability was assessed by a CCK8 toxicity assay. G The colony formation assay showed the proliferation abilities of the indicated cells. H Transwell migration and invasion assays showed the migration and invasion abilities in different MHCC-97H cell groups. Scale bar, 100 μm. I Measurement of the expression levels of cancer stemness markers, including NANOG, OCT4, and SOX2, in MHCC-97H and SNU-398 cells treated with different culture media. For the statistical analysis, ns, no significance, *P < 0.05, **P < 0.01, and ***P < 0.001, t test