In mice with large established (~125 mm3) orthotopic mammary tumors of 4T1HA cells, MagPix multiplex cytokine bead array showed that bortezomib treatment significantly increased protein levels of immunostimulatory cytokines IL-2, IL-12p40, IL-12p70, and IL-15, and decreased the levels of tumor-promoting cytokines IL-1β and VEGF in the splenic lysates when compared with protein levels in untreated mice with tumor alone (Figure 1 and Table 1). Here, VEGFA is linked to breast cancer.