CXCL8 and neuroblastoma: Despite a possible decrease in the antiapoptotic resistance of SH-SY5Y cells, the proliferative activity of the cells in the triple co-culture was higher than in the double ones and the monocultures of neuroblastoma cells, which could be explained by an increased concentration of a number of cytokines (CXCL8/IL-8, I-TAC/CXCL11, IP10/CXCL10, MDC/CCL22, IL1β, ENA-78/CXCL5, Gro-a/CXCL1, MCP-1/CCL2, TECK/CCL25, and IL-6) secreted by PBMCs and BM-MSCs.