Studies on alkaline phosphatase isoenzyme in gastric carcinoma tissues

An analysis of the alkaline phosphatase (ALP) isoenzyme in 75 gastric carcinoma tissues was performed. The properties and the originating cells of ALP isoenzymes in them were clarified by using both enzyme histochemical and biochemical methods which had respective superiorities. Also the relationship between intestinal metaplasia and gastric carcinoma was discussed. Liver, placental and small intestinal type ALPs were found in the carcinoma tissues. No ALP activity was found in the carcinoma cells except in the stromal cells in 46 out of 75 cases. In all of these cases, only liver type ALP was found. While, in 29 cases, the activity was also found in carcinoma cells. In these cases, placental and small intestinal type ALPs were found in addition to liver type ALP in 26 and 3 cases, respectively These results indicated that liver type ALP came from the stromal cells and placental and small intestinal type ALPs came from carcinoma cells. The ALP found in carcinoma cells was placental (Nagao isoenzyme) type in most cases. While, the ALP in intestinal metaplastic epithelial cells was small intestinal type in all cases. No sufficient evidence indicating the relationship between intestinal metaplasia and gastric carcinoma was obtained in respect of ALP isoenzyme.