PRF1 and neoplasm: Primary tumor growth was comparable between <i>WT</i> and <i>Cxcr2</i><sup>-/-</sup> mice, whereas lung metastasis was significantly increased in <i>Cxcr2</i><sup>-/-</sup> mice, with reduced expression of inflammatory cytokines, chemokines and cytotoxic molecules, including granzyme B and perforin, in primary tumors and metastatic lungs of <i>Cxcr2</i><sup>-/-</sup> mice.