LYSOSOMAL ENZYMES IN MACROPHAGES OF COLONIC TUMORS INDUCED IN RATS BY 1,2-DIMETHYLHYDRAZINE DIHYDROCHLORIDE

  • 1 January 1978
    • journal article
    • research article
    • Vol. 38  (9) , 2763-2767
Abstract
Ten weekly doses of dimethylhydrazine (30 mg/kg) were given to rats to induce colonic tumors. Histochemical and electron cytochemical studies revealed a distinct pattern of lysosomal acid phosphatase and .beta.-glucuronidase activity in macrophages in the stroma of these neoplasma. A dramatic increase in the number of acid phosphatase-rich macrophages was present in adenomas when compared to that in normal colonic mucosa. Fewer numbers of these cells were seen in well-differentiated adenocarcinomas, and they were barely detectable in invasive mucinous adenocarcinomas. These macrophages may play a role in preventing the invasion of adenomatous neoplasms into the submucosa. Application of histochemical techniques to study macrophage lysosomal enzymes may prove a useful diagnostic tool in differentiation of human colonic tumors for prognostic evaluation.