Some cationic polymers, such as polyethyleneimine (PEI) and cationic dextran, have shown their capacity to modulate by TLR4 signaling the immunosuppressive profile of myeloid-derived suppressor cells (MDSCs) towards an anti-tumor phenotype with an effective restoration of T cell activity and a reduction of the tumor growth in 4T1-tumor-bearing mice [51]. This evidence concerns the gene TLR4 and neoplasm.