Tumorigenesis has been considered to be as a result of abnormal cell-cell communication. It has been proposed that exosomes act as communicators between tumors and their microenvironment and have been demonstrated to be involved in tumorigenesis and subsequent metastasis. However, the mechanisms underlying the role of exosomes in these processes remains elusive. The present study sought to determine the underlying mechanisms. Using two lung cancer cell lines, it was demonstrated that exosomes derived from metastatic small cell lung cancer cells (NCI-H1688) have greater effects on cancer cell migration, compared with exosomes derived from primary non-small cell lung cancer cells (NCI-H2228). Further characterization of the contents of the exosomes demonstrated that there were increased levels of TGF-β and IL-10 in exosomes from NCI-H1688 cells compared with exosomes derived from NCI-H2228 cells, in particular under hypoxia. Blockade of TGF-β and IL-10 with antibodies confirmed that these cytokines were essential for the regulation of cancer cell migration. Taken together, the results of the present study indicated that exosomes derived from cancer cells regulated the cellular migration of tumor cells through TGF-β and IL-10, which may provide a novel approach for developing therapeutic methods against cancer.
Keywords: exosomes; lung cancer; migration; tumor.