This distribution pattern was found to be consistent with that reported by Wang and Liu [25].This expression pattern of OPN could be explained by the argument of Wang and Liu [25] who stated that OPN protein is probably synthesized and secreted by stellate reticulum like cells, picked up by ameloblast like cells and released into the peritumor nest stromal tissue (transcytosis in ameloblast like cells) in ameloblastoma. The gene discussed is SPP1; the disease is ameloblastoma.