However, the most consistently differentially expressed gene from chr18q21 in ABC-DLBCL was TCF4. This gene encodes a transcription factor also known as E2-2, which can drive SPIB expression and co-operate with SPIB to regulate the transcriptional program of plasmacytoid dendritic cells [63], [64]. This evidence concerns the gene SPIB and aneurysmal bone cyst.