CXCR4 and follicular lymphoma: We determined the expression levels of CXCR4, CXCR7, and their ligand CXCL12 [19] in NGCB- and GCB-DLCBLs consisting of primary and transformed follicular lymphomas (n = 71 in total) and germinal center B cells (GC-B, n = 5) serving as non-neoplastic controls by using RQ-PCR.