Urine Biomarker Helps Detect Aggressive Bladder Cancer

By LabMedica International staff writers
Posted on 10 Dec 2013

A simple urine test could distinguish between aggressive and less aggressive bladder cancers and quickly detect patients with the most advanced forms of the disease, helping to tailor and speed up their treatment.

The epithelial cell adhesion molecule (EpCAM) is overexpressed in bladder tumors and released from bladder cancer cells in vitro and therefore urinary EpCAM could act as a biomarker for primary bladder cancer detection and risk stratification.

Image: Histopathology of urothelial carcinoma of the urinary bladder from a transurethral biopsy (Photo courtesy of Wikipedia).

Scientists at University of Birmingham (UK) and their Dutch colleagues collected urine from 607 patients with primary bladder tumors and urine from 53 noncancer controls. The level of the protein EpCAM in the urine samples was measured by an enzyme linked immunosorbent assay (ELISA) and the structure of urinary EpCAM was investigated by western blotting and mass spectrometry.

The EpCAM ELISA utilizes capture and detection antibodies raised against the extracellular domain of recombinant human EpCAM (R&D Systems Europe Ltd; Abingdon, UK). EpCAM was significantly elevated in patients with urothelial bladder cancer (UBC), median 6.74 pg/mg creatinine compared with 3.86 pg/mg creatinine in the controls. Alongside grade and stage, elevated urinary EpCAM of greater than 24 pg/mg creatinine is an independent indicator of poor prognosis with a hazard ratio of 1.76 for bladder cancer-specific mortality. The soluble form of EpCAM in urine is the extracellular domain generated by cleavage between ala243 and gly244.

Douglas G Ward, PhD, the senior author of the study, said, “This protein could be used to help doctors to decide what the best course of investigation or treatment for the patients is, and may prevent unnecessary delays. We’ve known for some time that the protein EpCAM is released from some tumor cells but it wasn’t clear whether it would be useful as a way to decide the best investigation and treatment for patients suspected of having bladder cancer. We are now planning further studies to test the benefits of urine biomarker testing to patients and the UK National Health Service NHS.” There are around 10,300 cases of bladder cancer are diagnosed every year in the UK. The study was published on November 28, 2013, in the British Journal of Cancer.

Related Links:
University of Birmingham
R&D Systems Europe Ltd.