Fig. 6: CD26+ NFs are recruited toward tumor cells and induce invasiveness.

A, B Representative result of fibroblast migration toward tumor cells. Transwell assays were used to assess the recruitment of CD26− and CD26+ fibroblasts toward ILC-derived tumor cells (A) and TNBC-derived tumor cells (B). Tumor cells were plated in the bottom compartment and fibroblasts were plated in Matrigel-coated inserts. 24 h after plating the bottom-side of the inserts were fixed and stained with crystal violet to visualize the migrated cells. All assays were done in low serum conditions (0.2% FCS). 20% FCS and 0.2% FCS alone were used as positive and negative controls, respectively. Scale bars are 120 um. C Quantification of transwell assays (n = 7 independent experiments with similar outcome, WB1P n = 6). Statistical significance was determined using two-tailed Student’s t test. Bars represent mean ± SEM. D Representative result of organotypic invasion assay, in which collagen-containing gels are loaded with CD26− or CD26+ NFs or left empty. Tumor cells are plated on top of these gels and invasion into the gels is assessed after 1 week. Gels are processed as HE slides or stained for EpCAM to visualized tumor cells. Scale bars are 200 um. E Quantification of organotypic invasion assays based on EpCAM staining (n = 5 for TUM only, n = 7 for TUM + NFs conditions). All replicates shown are independent experiments with similar outcome. Invasion was measured in um from top of the gel to the invasive front of the tumor cells. Bars represent mean ± SEM. Statistical significance was determined using two-tailed Student’s t test. Source data for C and E are provided in source data file.