The clinical significance of circulating GPC1 positive exosomes and its regulative miRNAs in colon cancer patients

• DOI: 10.18632/oncotarget.20516
• Publication Date: 2017-08-27T12:03:47Z
• Authors: Jian Li; Bo Li; Caiping Ren; Yuxiang Chen; Xiong Guo; Lin Zhou; Zha Peng; Yaping Tang; Yang Chen; Weidong Liu; Bin Zhu; Lei Wang; Xuxu Liu; Xiao Shi; Zixuan Peng
• Keywords: 0301 basic medicine; 03 medical and health sciences; Research Paper; 3. Good health

Colorectal cancer (CRC) is a leading cause of cancer-related deaths worldwide. Recent study found an increased level of glypican-1 positive (GPC1+) plasma exosomes in patients with stage II CRC, but decreased levels of plasma miR-96-5p and miR-149. This study further investigated the clinical significance of plasma GPC1+ exosomes and plasma miR-96-5p and miR-149 levels in stage III CRC patients. To study the effect of these microRNAs on GPC1+ plasma exosomes, we isolated and purified exosomes and overexpressed human GPC1 and the microRNAs miR-96-5p and miR-149 by adenovirus vectors. Overexpression of GPC1 activated epithelial-mesenchymal transition (EMT) which then increased invasion and migration in HT29 and HCT-116 colon cancer cells. In contrast, silencing GPC1 expression and overexpressing miR-96-5p and miR-149 significantly inactivated EMT and decreased invasion and migration of HT29 and HCT-116 cells. miR-96-5p and miR-149 inhibitors significantly increased invasion and migration of HT29 and HCT-116 cells. Our results indicate that high levels of circulating GPC1 positive exosomes before and after surgery as well as low circulating miR-96-5p and miR-149 before surgery indicated a severe clinical status and poor prognosis in stage III colon cancer patients. We conclude that GPC1 can be a biomarker for relapse of stage III CRC and may be involved in EMT activation, invasion, and migration of colorectal cancer cells.