Fig. 2
From: Exosomes: key players in cancer and potential therapeutic strategy

Signal transduction pathway of exosomes in tumor microenvironment. The most important cells in tumor microenvironment mainly include CAFs, CSCs, MSCs, TMICs, etc. These four types of cells use exosomes to promote EMT, tumor metastasis and drug resistance through a variety of mechanisms. CAFs cancer-associated fibroblasts, CSCs cancer stem cells, MSCs mesenchymal stromal cells, TMICs tumor microenvironmental immune cells