CXCR2 and neoplasm: In this study, it was demonstrated that activation of CXCR2 has induced senescence in luminal-A breast tumor cells and limited tumor growth and metastasis; but in parallel, the pro-metastatic potential of the cancer cells was elevated when they were co-injected with PTTG-1-over-expressing MCF-7 cells, by creating a metastasis-promoting TME (65).