PECAM1 and neoplasm: In regional lymph nodes along the lesser gastric curvature prior to metastasis, the control group showed already existed, aggregated, high intensity of CD97 protein expression, as well as the elevated intensity of CD44, VEGF and CD31 expression; while the CD97/EGF1,2,5 kd clones showed comparatively scattered and down regulated transmembrane receptors protein expression, which indicated CD97 small isoform may also contribute to the metastasizing tumor cells settlement and involved in the preparation of the metastatic niche formation.