Hsa-miR-370 inhibited P-selectin-induced cell adhesion in human colon adenocarcinoma cells

Sialyl Lewis x (sLe^x) is a minimal recognition motif for ligands of P-selectin and plays an important role in tumor cell adhesion and migration. Thus, targeting sLe^x could be an effective method to prevent tumor metastasis. In this study, we aimed to identify a microRNA (miRNA) which is capable to suppress the expression of sLe^x. MicroRNAs which may target ST3GAL4 were predicted by the online tools. Colo 320 HSR human colon adenocarcinoma cells were employed. The transcriptional and translational levels of ST3GAL4 were evaluated by western blotting and Real-time quantitative polymerase chain reaction. Cell adhesion and spread were assessed with or without hsa-miR-370 treatment. It was shown that hsa-miR-370 inhibited the expression of sLe^x in colo-320 cells, which repressed the binding of P-selectin, and led to reduced cell attachment and spread. Our results found that P-selectin-induced elevations of p-p38 and p-PI3K levels were significantly inhibited by hsa-miR-370, indicating that repressed sLe^x level is able to reduce the P-selectin binding and therefore eliminating the P-selectin-induced activation of p38 and PI3K signaling. In conclusion, we found that hsa-miR-370 specifically inhibits the expression of sLe^x, represses cell adhesion and spreading in colo-320 cells. Our study provides a possible effective treatment against tumor invasion.