CCR1 and neoplasm: An in vitro evaluation of a clinical trial for oncolytic virotherapy with 12 patients revealed that receptor/ligand pairs C-X-C motif chemokine receptor-1 (CXCR1)/IL-8 and CC chemokine receptor 1/CC chemokine ligand 5 (CCR1/CCL5) were involved in successful migration of MSCs to the tumor [52] (Fig. 1A).