ELISA measurement for urinary 3-hydroxyproline-containing peptides and its preliminary application to healthy persons and cancer patients

Background/Aim: We reported that endogenous urinary 3-hydroxyproline (3-Hyp) is useful for cancer screening because cancer invasion involves the destruction of basement membrane. A simple and sensitive assay is desired. Patients and Methods: An ELISA method using a specific antibody against a synthetic peptide of 10 amino acids including 3-Hyp corresponding to the amino acid sequences of collagen type IV alpha chain was applied to urine samples from 180 healthy controls and 22 cancer patients. Results: The values in controls were 2.44±1.90 (SD) mg peptide/g creatinine for 52 men and 2.87±2.01 for 128 women, while the values in 22 cancer patients were very low at 0.110±0.137 (p<0.001). Discussion: The discrepancy in the data between our previous and present studies is based on the difference of targets measured. 3-Hyp-containing peptides in cancer patients might be destroyed by the elevated peptidase levels found in these patients. Conclusion: This ELISA assay may be useful for cancer screening.