CXCL12 and cancer: Figure 5c shows values of PC1 and PC2 for each specific cytokine, by which TGF-β, MIF, CCL2, CXCL5, CXCL8 and CXCL12 were suggested as key regulators in determining the behavior of examined cancer cells line and particularly in modulating the response to RT of RH30-RR cells.