1. Determination of the complex between urokinase and its type-1 inhibitor in plasma from healthy donors and breast cancer patients
- Author
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An, Pedersen, Brünner N, Høyer-Hansen G, Hamer P, Jarosz D, Larsen B, Hj, Nielsen, and Rw, Stephens
- Subjects
Male ,Reproducibility of Results ,Breast Neoplasms ,Enzyme-Linked Immunosorbent Assay ,Middle Aged ,Sensitivity and Specificity ,Urokinase-Type Plasminogen Activator ,Plasminogen Activator Inhibitor 1 ,Biomarkers, Tumor ,Humans ,Female ,Aged ,Neoplasm Staging ,Protein Binding - Abstract
The complex between urokinase (uPA) and its type-1 inhibitor (PAI-1) is formed exclusively from the active forms of these components; thus, the complex concentration in a biological sample may reflect the ongoing degree of plasminogen activation. Our aim was to establish an ELISA for specific quantification of the uPA:PAI-1 complex in plasma of healthy donors and breast cancer patients.A kinetic sandwich format immunoassay was developed, validated, and applied to plasma from 19 advanced-stage breast cancer patients, 39 age-matched healthy women, and 31 men.The assay detection limit was2 ng/L, and the detection of complex in plasma was validated using immunoabsorption, competition, and recovery tests. Eighteen cancer patients had a measurable complex concentration (median, 68 ng/L; range,16 to 8700 ng/L), whereas for healthy females and males the median signal values were below the detection limit (median,16 ng/L; range,16 to 200 ng/L; P0.0001). For patient plasma, a comparison with total uPA and PAI-1 showed that the complex represented a variable, minor fraction of the uPA and PAI-1 concentrations of each sample.The reported ELISA enables detection of the uPA:PAI-1 complex in blood and, therefore, the evaluation of the complex as a prognostic marker in cancer.
- Published
- 1999