Examples of various patterns of AQP3. Homogeneous, cell membrane-associated expression of AQP3 in a low-grade papillary tumour (top left, 10-fold magnification). Regular expression in the basal and suprabasal, but not superficial cell layers in a section of normal human ureter (top right, 40-fold magnification). Heterogeneous expression of AQP3 in a high-grade pT1 tumour (bottom left, 40-fold magnification). Lack of expression in another pT1G3 UBC specimen (bottom right, 10-fold magnification).