PDE4B and aneurysmal bone cyst: From the gene expression in the training data and validated data, a gene set (MYBL1, LMO2, MME, and BCL6) was significantly overexpressed in GCB subtype relative to the level of ABC; Inversely, the other set (IRF4, PDE4B, NKFBIZ, and SLA) was significantly more level in ABC than GCB group.