title: Variation of leukocyte neuraminidase with Duke stage in patients with adenocarcinoma of the colon and rectum.
abstract: In 14 patients with adenocarcinoma of the colon or rectum (Duke stages A to D), positive results for neuraminidase were obtained with the isolated leukocytes at pH 6. These were tested by a cytochemical method using a chromogenic substrate for neuraminidase. Under the same conditions, normal leukocyte neuraminidase has a pH optimum of 4. The percentage of leukocytes showing neuraminidase activity increased with the progression of Duke stage and presence of liver or peritoneal metastases. Neuraminidase activity was also found in tumor and metastases specimens of these patients as well as in a human cell line derived from colonic adenocarcinoma (HT-29). Neuraminidase antibodies were found in blood and certain tumor materials. Neuraminidase inhibition tests were positive with neuraminidase inhibitors, patients' sera, N2 neuraminidase antibodies, and antisera against some type C retroviruses (GaLV and MLV), which were used because highly purified MLV preparations proved to contain biologically active neuraminidase (N2).
authors.affiliation: Research Group of Viruses and Tissue Cultures, National Research Center, Dokki, Cairo, Egypt.
authors.forename: E N
authors.initials: EN
authors.lastname: Arida
mesh_terms: D000230:Adenocarcinoma / Q000201:enzymology* / Q000473:pathology; D000368:Aged; D001706:Biopsy; D002460:Cell Line; D003110:Colonic Neoplasms / Q000201:enzymology* / Q000473:pathology; D005260:Female; D006801:Humans; D007962:Leukocytes / Q000201:enzymology*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009439:Neuraminidase / Q000276:immunology / Q000378:metabolism*; D012004:Rectal Neoplasms / Q000201:enzymology* / Q000473:pathology
chemical_list: D009439:Neuraminidase