CXCR1 and neoplasm: CRIP1 expressed in tumor cells promotes the infiltration of MDSCs via CXCL1/5-CXCR1/2 signaling, and the inhibition of CXCR1/2 decreases the recruitment of MDSCs and enhances the antitumor effect of PD-L1 treatment to improve resistance to immune-checkpoint blockers(ICBs) [37].