Zinc in native tissues and cultured cell lines of human prostate studied by SR-XRF and XANES

During longlasting attempts to understand the aetiology of prostate cancer (Cap) on molecular level, attention has been paid to a unique capability of prostate epithelial cells to accumulate zinc. The latter plays role in a wide range of cellular processes such as the function of immune system, angiogenesis or apoptosis. Zinc has a significant antioxidant function, and its presence in prostate cells is strongly connected with their metabolism. This paper reports on the analysis of zinc concentration and oxidation level in the samples of human Cap tissues and cultured human prostate cell lines such as DU-145, LNCaP and PC-3, aided by x-ray bioimaging. The study was performed by means of synchrotron radiation (SR) techniques. Bioimaging on cellular level, available through the SIR x-ray fluorescence (SR-XRF) methods, applied to the samples of native prostate tissue, revealed a complexity of structures, while cell culture samples provided areas of homogeneity required for reliable analysis. SR-XRF enabled us to establish the dependence of zinc concentration upon histological status of tissue (healthy, hyperplastic or cancerous). In-depth studies of local chemical environment of an x-ray absorbing zinc atom, including determination of Zn K-edge position, were possible through the use of x-ray absorption near edge structure (XANES) analysis. Copyright (C) 2009 John Wiley & Sons, Ltd.