Brundl J, et al. - Researchers sought to study the expression pattern, localisation and potential clinical significance of aquaporin water channels (AQP) both in prostate cancer (PC) cell lines and in benign and malignant human prostate tissue. Human prostate cell lines, benign prostatic hyperplasia and PC were systematically characterized in relation to all 13 members of the AQP family for the first time in this study. In benign and malignant prostate tissue, the differential expression of several AQPs was indicated by the findings. AQP 3 expression was significantly correlated to the tumour grade, with progressive loss in more malignant tumours. Taken together, a role in the progression of PC could be played by the AQPs and the prognostic marker may be AQP expression patterns.