Figure 4 from HuR-Regulated Extracellular Vesicles Promote Endothelial Cell Remodeling in Pancreatic Cancer

Tumor-intrinsic HuR promotes endothelial cell recruitment and sprouting in PDAC tumors. A, Immunoblot of KPC WT and HuR-KO clones 6, 8, and 9 probed for HuR and loading control vinculin. B, KPC WT and HuR-KO cells were implanted orthotopically into the pancreas of immunocompetent C57BL6 mice, and tumor volume (mm³) was measured after 14 days (WT n = 6; HuR-KO n = 10). C, KPC WT vs. HuR-KO IF staining for endothelial cells (endomucin, magenta) and nuclei (DAPI, teal; scale bar, 100 µm; WT n = 7 and HuR-KO n = 6). D, Ultrasound power Doppler imaging of orthotopic KPC WT and HuR-KO tumors to quantify percent vascularity at 13 days after implantation with tumor border in green and blood flow in red (WT n = 5; HuR-KO n = 4; scale bar, 1 mm). IF co-staining of KPC WT vs. HuR-KO tumors for (E) endothelial cells (endomucin, magenta) and sprouting (DLL4, white) and (F) endothelial cells (CD31, magenta) and ICAM-1 (white; scale bar, 100 µm; n = 5). P values were calculated using an unpaired two-tailed Student t test. *, P < 0.05; **, P < 0.01; ***, P < 0.001; ns, not significant.