Our proposed scheme of prostate cancer de-differentiation could proceed from Gleason pattern 3 adenocarcinoma/LNCaP → C4–2B → Gleason pattern 4 → PC3/non-adenocarcinoma (LuCaP 173)/SOX2+ small cell carcinoma LuCaP 49 [2] → LuCaP 93 → LuCaP 145. Here, SOX2 is linked to small cell carcinoma.