PT - JOURNAL ARTICLE AU - AYA TOKUDA AU - TORU MIYAKE AU - DAIKI YASUKAWA AU - DAIJI IKUTA AU - KEN-ICHI MUKAISHO AU - SATOSHI MURATA AU - TOMOHARU SHIMIZU AU - MASAJI TANI TI - Cancer-derived Exosomes Activate Immune Surveillance and Suppress Peritoneal Metastasis of Murine Colonic Cancer AID - 10.21873/anticanres.14890 DP - 2021 Mar 01 TA - Anticancer Research PG - 1327--1339 VI - 41 IP - 3 4099 - http://ar.iiarjournals.org/content/41/3/1327.short 4100 - http://ar.iiarjournals.org/content/41/3/1327.full SO - Anticancer Res2021 Mar 01; 41 AB - Background: Colonic cancer is associated with a low incidence of peritoneal metastasis compared with gastric cancer; however, the reason for this remains unclear. In this study, a model of peritoneal dissemination using the CT26 murine colon cancer cell line was used to analyze the physiological roles of cancer-derived exosomes. Materials and Methods: Exosomes were collected from the supernatant of CT26 cell culture by ultracentrifugation. The number of peritoneal disseminations in two mouse models of colonic cancer pre-administered exosomes or phosphate-buffered saline were compared. Results: Cancer-derived exosomes suppressed peritoneal dissemination compared to phosphate-buffered saline. After administration of exosomes, the number of intraperitoneal macrophages and the expression of inducible nitric oxide synthase increased. Furthermore, cancer-derived exosomes increased activated natural killer cells and interferon-γ expression. Conclusion: Tumor-derived exosomes from colonic cancer may suppress peritoneal metastasis via an immunological mechanism.