Endothelial cells appear to express phosphorylated PDGF-R when they are exposed to tumor cells that express PDGF. Using STI571 to inhibit PDGF-R phosphorylation may, especially in combination with paclitaxel, produce substantial therapeutic effects against prostate cancer bone metastasis.

We determined whether the expression of interleukin-8 (IL-8) by human prostate cancer cells correlates with induction of angiogenesis, tumorigenicity, and production of metastasis. Low and high IL-8-producing clones were isolated from the heterogeneous PC-3 human prostate cancer cell line. The secretion of IL-8 protein correlated with transcriptional activity and levels of IL-8 mRNA. All PC-3 cells expressed both IL-8 receptors, CXCR1 and CXCR2. The low and high IL-8-producing clones were injected into the prostate of nude mice. Titration studies indicated that PC-3 cells expressing high levels of IL-8 were highly tumorigenic, producing rapidly growing, highly vascularized prostate tumors with and a 100% incidence of lymph node metastasis. Low IL-8-expressing PC-3 cells were less tumorigenic, producing slower growing and less vascularized primary tumors and a significantly lower incidence of metastasis. In situ hybridization (ISH) analysis of the tumors for expression of genes that regulate angiogenesis and metastasis showed that the expression level of IL-8, matrix metalloproteinases, vascular endothelial growth factor (VEGF), and E-cadherin corresponded with microvascular density and biological behavior of the prostate cancers in nude mice. Collectively, the data show that the expression level of IL-8 in human prostate cancer cells is associated with angiogenesis, tumorigenicity, and metastasis.

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Background/AimsNephrotoxicity is a frequent and major limitation in cisplatin (CDDP)-based chemotherapy. 5-Aminolevulinic acid (ALA) is widely distributed in animal cells, and it is a precursor of tetrapyrole compounds such as heme that is fundamentally important in aerobic energy metabolism. The aim of this study is to evaluate the protective role of ALA in CDDP-induced acute kidney injury (AKI).MethodWe used CDDP-induced AKI rat model and cultured renal tubular cells (NRK-52E). We divided four groups of rats: control, CDDP only, CDDP + ALA(post);(ALA 10 mg/kg + Fe in drinking water) after CDDP, CDDP + ALA(pre & post).ResultCDDP increased Cr up to 6.5 mg/dl, BUN up to 230 mg/dl, and ALA significantly reduced these changes. ALA ameliorates CDDP-induced morphological renal damages, and reduced tubular apoptosis evaluated by TUNEL staining and cleaved caspase 3. Protein and mRNA levels of ATP5α, complex(COX) IV, UCP2, PGC-1α in renal tissue were significantly decreased by CDDP, and ALA ameliorates reduction of these enzymes. In contrast, Heme Oxigenase (HO)-1 level is induced by CDDP treatment, and ALA treatment further up-regulates HO-1 levels. In NRK-52E cells, the CDDP-induced reduction of protein and mRNA levels of mitochondrial enzymes was significantly recovered by ALA + Fe. CDDP-induced apoptosis were ameliorated by ALA + Fe treatment. Furthermore, we evaluated the size of transplantated bladder carcinoma to the rat skin, and ALA did not change the anti cancer effects of CDDP.ConclusionThese data suggested that the protective role of ALA in cisplatin-induced AKI is via protection of mitochondrial viability and prevents tubular apoptosis. Also there are no significant effects of ALA on anticancer efficiency of CDDP in rats. Thus, ALA has the potential to prevent CDDP nephrotoxicity without compromising its anticancer efficacy.

These data advance the hypotheses that VEGF expression and an "invasive phenotype" characterized by the ratio of MMP-9-to-E-cadherin expression are mechanistically relevant to clinically aggressive locally advanced bladder cancers that are not cured by currently available combined modality treatment. Thus, in our view there is a compelling rationale to target these aspects of the malignant phenotype in this patient population.

Purpose: The purpose of this study was to clarify the regulatory mechanism of protoporphyrin IX (PpIX) synthesis mediated by 5-aminolevulinic acid (ALA) in human urothelial carcinoma (UC), leading to improved accuracy in photodynamic diagnosis and therapy using ALA. Experimental Design: PpIX accumulation in cultured UC cells after incubation for 1–5 h with 0.5–5 mM ALA was analyzed by fluorescence analysis using fluorescence microscopy and flow cytometry technique. Results: PpIX fluorescence mediated by ALA was increased, and the intensity of PpIX fluorescence was time-dependently increased in UC cells compared to noncancerous cells. The distribution of endogenous PpIX fluorescence primarily coincided with mitochondria, and then increased at a specific perinuclear region in the cells during the time of incubation. The ALA-mediated PpIX synthesis in UC cells was suppressed by β-alanine, an inhibitor of β-transporters of cell membrane, and carbonylcyanide p-trifluoromethoxyphenyl hydrazone, an uncoupler of mitochondrial oxidative phosphorylation. In contrast, the ALA-mediated PpIX accumulation was increased by deferoxamine, an iron chelator, manganese and nitric oxide, which is contributed to PpIX metabolism by inhibiting ferrochelatase activity, generated by a nitric oxide-generating reagent NOC-18. As observed above, ALA-mediated PpIX synthesis in human UC cells was regulated by the process of ALA uptake, ALA conversion to PpIX and metabolism of accumulated PpIX to heme. Conclusions: This shows that the suppression of ferrochelatase increased PpIX accumulation in UC cells using small amount of ALA, thus leading to an improved clinical practicability of photodynamic diagnosis and therapy.

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Objective: This study was designed to determine the relative activity of angiogenesis-related genes in the regulation of tumorigenicity and subsequent metastases of urothelial cell carcinomas (UC) of the urinary bladder. Methods: We selected the clones with the highest and lowest expression level of basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF)/vascular permeability factor or interleukin-8 (IL-8) in the highly tumorigenic and metastatic human UC cell line 253J B-V. Tumorigenicity and production of spontaneous lymph node metastases were evaluated 1, 2, 4, 8 and 12 weeks after orthotopic implantation of each specific expression clone into the urinary bladder of athymic nude mice. Moreover, the transitional changes in the expression of angiogenesis-related genes and neovascularization were determined in tumors and metastases. Results: At the early stage of tumor growth following orthotopic implantation, tumorigenicity and metastases were significantly increased in the clones with the highest expression of bFGF and IL-8, while they were significantly inhibited in the clones with the lowest expression of bFGF and IL-8 compared to parental 253J B-V. In the tumors, specific expression of angiogenesis-related genes and intratumor neovascularity of each clone were gradually regulated to the same level as parental 253J B-V. In metastasized tumors of the highest and lowest IL-8-expressing clones, IL-8 expression was consistently high and low, respectively. Conclusions: These findings indicate that at the early stage of tumor growth, bFGF and IL-8 expression play important roles in the regulation of angiogenesis, tumorigenicity and subsequent metastases of human bladder cancer.