The mechanism of immune microenvironment reshaping by exosomal miRNAs. Exosomes secreted by the primary tumor cells are taken up by the receptor immune cells, wherein the exosomal miR-212-3p target the MHC class II TF RFXAP complexus and activate the HLA-DR, -DP, and -DQ molecules. The exosomal miRNAs (miR-222-3p, miR-21, miR-10a, etc.) target the proteins (SOCS3, PTEN, RORA, etc.) and activate the molecules (p-STAT3, p-p65, p-AKT, p53, etc.). These exosomal miRNAs reshape inmune microenvironment by mediating immunosuppression.