CXCR4 and hematopoietic and lymphoid cell neoplasm: To assess the role of FtH on CXCR4 signaling in hematological tumors, we first measured CXCR4 levels in K562shFtH and in K562shRNA and we found that FtH knock down significantly enhanced CXCR4 expression at both mRNA and protein levels (Figure 1A).