Statistical data were presented in histograms (KLF2(total)/DAPI area ratio: PBS, 0.027 ± 0.0034; EXO, 0.012 ± 0.0055; KLF2(tumor)/DAPI area ratio: PBS, 0.023 ± 0.0025, EXO, 0.011 ± 0.0052; KLF2(vessel)/CD31 area ratio: PBS, 0.026 ± 0.012, EXO, 0.0049 ± 0.0026, *P < 0.05, **P < 0.01) (Fig. 8B). The gene discussed is PECAM1; the disease is neoplasm.