Fig. 4

The TRAIL-TRAILR axis leads to CCL2 secretion by tumor cells. A Schematic outline of the RNA-seq. After incubation of 4T1 cells with 100 ng/mL smTRAIL or PBS for 24 h, the cells were harvested for transcriptome sequencing. B Heatmap of functional genes differentially expressed in smTRAIL and control. C After 4T1 cells and CT26 cells were incubated with smTRAIL for 24 h, the levels of Ccl2 mRNA were analyzed by real-time RT-PCR and normalized to β-actin (n = 3). D The levels of Ccl2 mRNA in 4T1 tumor tissue and CT26 tumor tissue was analyzed by real-time RT-PCR and normalized to β-actin (n = 5). E The secretion of CCL2 in 4T1 tumor tissue and CT26 tumor tissue were analyzed (n = 5). F UMAP plots demonstrating the cancer cell cluster distribution for each treatment group. G Stacked histograms of the frequencies of clusters in the groups. H Trajectory plot of macrophage clusters. I The expression levels of relative genes are shown in the density plot. J After 4T1-TRAILR-KO cells and CT26-TRAILR-KO cells were incubated with smTRAIL for 24 h, the levels of Ccl2 mRNA were analyzed by real-time RT-PCR and normalized to β-actin (n = 3). K Tumor growth curves (n = 6). L The level of Ccl2 mRNA in CT26-TRAILR-KO tumor tissue was analyzed by real-time RT-PCR and normalized to β-actin (n = 5). M Representative images of CT26-TRAILR-KO tumor-bearing mice treated with smTRAIL. Tumor tissues stained with DAPI and anti-CD206. Scale bars, 50 μm. N The level of Il-10 mRNA in CT26-TRAILR-KO tumor tissue was analyzed by real-time RT-PCR and normalized to β-actin (n = 5). Statistical analysis was carried out by unpaired t-test, one-way ANOVA, and two-way ANOVA test. *P < 0.05; ***P < 0.001; and ****P < 0.0001