title: Serum 5'-nucleotidase: automation of a manual assay and brief observations on values in patients with breast cancer.
abstract: We have modified a manual assay method for the determination of serum 5'-nucleotidase so that the reaction product, phosphate, is assayed colorimetrically using a continuous flow system. The contribution of non-specific phosphatase enzymes is assessed in the presence of nickel ions which specifically inhibit 5'-nucleotidase. The detergent sodium lauryl sulfate is used to eliminate the need for deproteinization in the phosphate assay. We have measured 5'-nucleotidase activity in the sera of 123 breast cancer patients and correlated our data with the patients' clinical status. Receiver operating characteristic curve analysis showed the most advantageous cut-off point for indication of secondary spread to be 10 U/L. Using this cut-off point, 14% of patients who were clinically free of disease and 35% of patients with disease clinically present had elevated 5'-nucleotidase activity.
mesh_terms: D015720:5'-Nucleotidase; D001322:Autoanalysis / Q000379:methods; D001943:Breast Neoplasms / Q000201:enzymology*; D003124:Colorimetry; D005260:Female; D006801:Humans; D009708:Nucleotidases / Q000097:blood*; D010710:Phosphates / Q000032:analysis
chemical_list: D010710:Phosphates; D009708:Nucleotidases; D015720:5'-Nucleotidase