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The aim of the study was to quantify the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) in prostate cancer and adjacent non-tumorous tissue in a standardized experimental set-up and to evaluate the paracrine effects of three endothelial stimuli on neovascularisation. Immunohistochemical staining of prostate cancer (PCa) specimens for VEGF, bFGF, EGF and the endothelial marker CD31 was performed (n=56). Sections were analyzed for growth factor-positive cancer/epithelial cells as well as staining intensity in (I) malignant and (II) non-tumorous tissue. Within PCa the topographic relationship (TR) of maximum microvessel density (MWD) and maximum expression of each growth factor was assessed. The number of VEGF- and EGF-positive cells in PCa was significantly enhanced compared with non-tumorous tissue (p<0.0001), whereas there was no difference in staining intensity. In contrast, the staining intensity of bFGF sections revealed a stronger expression in non-tumorous tissue compared with PCa (p<0.0001). In benign glands, VEGF, EGF and bFGF expression is chiefly restricted to basal cells. VEGF and EGF displayed a close TR in 65 and 57% of cases, respectively, whereas bFGF revealed a close TR in only 43% of PCa specimens. The results outline the relationship of the investigated growth factors and angiogenesis in PCa, which is strongest for VEGF and EGF. The relevance of VEGF and EGF is underlined by the increased number of positive cancer cells. Although previously reported to be a pro-angiogenic growth hormone, bFGF appears to play an assimilably minor role in the angiogenesis of PCa. [ABSTRACT FROM AUTHOR]

Cystinuria is the cause of 1–2% of stones observed in adults and about 10% of those occurring in children. Recurrent stone formation and multiple operations cause considerable morbidity. We investigated the transfection efficiency of naked plasmid DNA in porcine kidney cells by applying holmium laser (Ho:YAG) energy in vitro as well as ex vivo in a porcine kidney papilla model. In the in vitro experiments, naked plasmid DNA was added to LLC-PK1 cells suspended in a medium and Ho:YAG laser applied with varying pulses. The transfection efficiency was measured by the expression of EGFP reporter gene in the cells by FACScan analysis and fluorescence microscopy. Ex vivo, papilla from porcine kidney was excised and naked plasmid DNA was added to the tissue in the medium. The laser was then applied and the cryosectioned tissue observed under fluorescence microscope. The efficiency of transfection in vitro significantly improved with the increase in impulses (P<0.01). Transfection at 50 impulses averaged 0.7±0.3%, at 200 impulses 28.3±7.7%, and at 500 impulses 36.1±3.1%. The cell mortality rate increased with higher pulse rate up to 70%. Ex vivo trials showed transfection in extended regions of the tissue and also in the peripheral layers of the papilla. Our study indicates that the transfection of benign kidney cells by Ho:YAG is a promising new gene transfer strategy. The ex vivo trials showed that peripheral renal tissue layers are susceptible to transfection by Ho:YAG applied from the papillary surface. [ABSTRACT FROM AUTHOR]