We recently found that Evans blue, a water-soluble diazo dye with intense blue colour, accumulates specifically in vitro in spheroids composed of urothelial cell carcinoma cells and in vivo in non-muscle-invasive bladder cancer in a AY-27 rat model. Our data also strongly point to the accumulation of Evans blue in the paracellular space secondary to a relative lack of intercellular cohesion between malignant cells. We believe therefore that our present findings on Evans blue are important for future clinical developments in the field of diagnostics for bladder cancer detection, staging and grading, and for interstitial cystitis (ICS) involving white-light cystoscopy. Anticipating its clinical use, it is essential to understand its mechanism of action and to optimize its use in relevant preclinical animal models. To that end the accumulation of Evans blue will be examined in vitro in multicellular spheroids prepared from normal human urothelial (NHU) cells and ICS cells isolated from patients, and prepared from different human urothelial cell carcinoma (UCC) cell lines. The spheroids will also be examined on their gene- and protein-expression signatures, focusing on cell-cell adhesion proteins and the GAG-layer, and ultrastructurally by transmission and scanning electron microsocopy. Furthermore, the in vivo biodistribution of Evans blue will be examined in the different layers (urothelium, submucosa, muscle) of a normal rat bladder and of an UCC orthotopic AY-27 rat bladder tumor model, and in the different layers of a normal cat bladder and of a cat interstitial cystitis bladder model, after intravesical instillation. Also the therapeutic effect of radiolabeled Evans blue (and its selectivity) will be investigated in vitro using the above-mentioned spheroids prepared from NHU cells and different human UCC cell lines, and in vivo using a normal rat bladder and an UCC orthotopic rat bladder tumor model.
Applicants must hold a master’s degree before the start of the fellowship, but not necessarily when applying.