Expression Of Exosome In Gastric Serum And Clinical Significance

Objective To investigate the serum exosome in gastric cancer patients and its clinicalsignificance.Methods We designed an ELISA to capture and quantify exosomes in plasma based onexpression of EXOSC2(exosome component2). We evaluated the levels of plasma exosomesexpressing EXOSC2in gastric cancer patients (n=77) and healthy donors (n=34). The relationship ofexosome levels with clinicopathological features was statistically analyzed.Results The median of exosome level in serum from gastric cancer patients andhealthy donors were670.92pg/ml(R=22974.88pg/ml) and585.49pg/ml(R=3575.95pg/ml). The exosome level in serum from gastric cancer patients was significantly higherthan healthy donors (P<0.05). The exosome level in serum from gastric cancer patientswas positively associated with lymph nodal metastasis status (P<0.01). Patients of gastriccancer with stages III and IV had significantly higher levels of exosome than those withstages I and II(P<0.05). Serum exosome expression was significantly associated withdifferentiation degree(P<0.05). In gastric cancer, the expression of exosome was notrelated to the age, gender, depth of invasion, distant metastasis and tumor size (P>0.05). Inthe diagnosis of gastric cancer, the sensitivities of exosome and CEAwere79.2%and24%,respectively. The areas under ROC curve of exosome and CEAwere0.649and0.753.Conclusion The increased exosome level in serum from gastric cancer patients wassignificantly correlated to nodal metastasis status, tumor stage and differentiationdegree,which suggests that levels of plasma exosomes might serve as the progressionestimation of gastric cancer.