The cancer cell types included prostate cancer cell lines LNCaP, C4-2, CL1, PC3, DU145, tumor xenografts LuCaP 35 and LuCaP 49, CD26+ Gleason pattern 3 (G3) and pattern 4 (G4) cancer cells isolated from primary tumors [8]. The gene discussed is DPP4; the disease is cancer.