In contrast, PAI-1 increased the production of CXCL5, suggesting that PAI-1 might increase the tumor infiltrating CXCR2+ myeloid-derived suppressor cells (MDSCs) and tumor-associated neutrophils (TANs) (Figure 3), both of which are known to be immunosuppressive cells 12. Here, CXCR2 is linked to neoplasm.