To determine whether high CXCR4 and CXCL12 mRNA expression translated into high protein levels, immunohistochemical analysis for CXCR4 and CXCL12 was performed on the DLBCL samples (Figure 1d, n = 40), for which enough material was left. The gene discussed is CXCR4; the disease is diffuse large B-cell lymphoma.