Fig. 5: TI cells co-opt collagenase-expressing G-MDSCs to facilitate tumor invasion.

a Percent of CD45⁺ cells present by flow cytometry in tongue epithelia at 1, 6, 10, and 15 days after transgene induction. Each time point was analyzed individually with p-values calculated by one-way ANOVA with Tukey correction for multiple comparisons (From days 0-15: N = 5, 3, 10, and 21 mice; E = 5, 5, 11, and 21 mice; Y = 4, 3, 8, and 17 mice; EY = 3, 1, 9, and 16 mice); means with SEM shown: **p < 0.01, ****p < 0.0001. b UMAP of immune cell clusters by scRNAseq, n = 11,2286 cells (n = 2 mice per group). c Stacked bar graph and d UMAP of immune cell types stratified by transgenic condition; N = 1,964, E = 1,571, Y = 5,163, EY = 2,583 cells (n = 2 mice per group). e Representative immunofluorescence images of pan-Cytokeratin, LY6G, and IBA1 expression in N, E, Y, and EY tongue epithelia 20 days after transgene induction; scale bars: all 20μm; n = 4 mice per group. f Expression of chemokine genes among epithelial clusters and corresponding receptor genes among immune clusters. g Representative H&E-stained sections (left) and collagen imaging by second harmonic generation microscopy (SHM, middle) in control epithelia (N) and infiltrative carcinoma (EY) 20 days after transgene induction. Right: fluorescent intensity of second harmonic generation signal at basement membrane and invasive front. n = 4 mice per group, one-way ANOVA with Tukey correction for multiple comparisons. Boxplots show median, interquartile range (IQR), and range. ***p < 0.001, ****p < 0.0001. Scale bars: 100 μm (left), 20 μm (right) for H&E and SHM. h Collagenase gene expression across epithelial and immune clusters. i Frequency (left) and burden of carcinoma per mouse tongue (right) after treatment of transgene-induced EY mice with control (n = 11) or anti-LY6G depleting antibody (n = 9). j Frequency of carcinoma (left) and carcinoma burden per mouse tongue (right) after treatment of transgened induced EY mice with vehicle (n = 23) or the CXCR1/2 dual inhibitor ladarixin (Ldx, n = 12); mean and standard error of the mean shown. For i and j, two-sided Mann-Whitney test. Panels a, i, j display biological replicates. See Source Data for panels a, g, i, j.