PECAM1 and neoplasm: To further explore the mechanism of PMS inhibition on tumor lung metastasis, we detected the biomarker of angiogenesis-CD31 in primary tumor tissues by IHC staining (Fig. 6g), after IPP software semi quantitative analysis, there were significant differences between the two groups (Fig. 6h) (P <0.01)(control vs. PMS is 0.37 ± 0.08 vs.0.19 ± 0.03).