CXCR1 and neoplasm: G31P is an analog of CXCL8 which has antagonistic effects against CXCR1/2 (Buller et al., 1988). The inhibition of CXCR2 signaling has been shown to decrease MDSC infiltration, suppression of angiogenesis, reduce tumor growth, and increased anti-PD-1 treatment sensitivity (Buller et al., 1988; Colamonici et al., 1995; Sigismund et al., 2018; Inoue et al., 2021)