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Chemokines undergo alterations during neoplasia. However, knowledge about their functional significance in prostate cancer (PCa) progression is still sparse. Since chemokine (C–C motif) ligand 2 (CCL2) is significantly up-regulated in patients with PCa, aim of the current study was to assess whether CCL2 contributes to invasive behavior of prostate cancer cells in vitro. The human PCa cell line PC3 was stimulated with CCL2. Cell growth was investigated by MTT dye reduction assay. Cell adhesion was analyzed by measuring attachment to a human endothelial cell (HUVEC) monolayer and immobilized collagen. Cell migration was assessed by a chemotactic assay. Integrin expression on the cell surface was evaluated by Western blot. Blocking studies were performed with anti-integrin α3, anti-integrin α6 and anti-integrin β4 monoclonal antibodies. PC3 cell growth 72 h after CCL2 exposure was significantly increased, compared to controls. Activation of tumor cells by CCL2 significantly enhanced tumor cell adhesion to HUVEC and immobilized collagen. CCL2, added for 4 or 24 h, elevated α6 and β4 (4 > 24 h) integrin expression. α3 was enhanced after 4 h, but reduced after 24 h. Blocking either α3, α6 or β4 led to significant suppression of tumor cell binding to immobilized collagen. CCL2 stimulates PCa cell adhesion and induces alterations in α3-, α6- and β4-integrin expression on the cell surface. Blocking these integrins leads to a significant reduction in cell adhesion.

Pharmacologic options for patients with castration-resistant prostate cancer are limited. It has been suggested that targeting intracellular molecules, which have been altered during neoplastic development, may slow tumor growth. Therefore, the growth-blocking potential of the histone deacetylase-inhibitor LBH589 and the multiple tyrosine kinase-inhibitor TKI258, applied alone or in combination, was investigated in a panel of prostate cancer cell lines. PC-3, DU-145 or LNCaP cells were treated with various concentrations of LBH589 and/or TKI258. Tumor cell growth, cell cycle regulating proteins, HDAC3- and HDAC4-expression and histone H3 and H4 acetylation were then evaluated by MTT assay and Western blotting. LBH589 dose-dependently blocked prostate cancer cell growth. In contrast, TKI258 did not down-regulate tumor cell growth up to a 1,000 nM dosage. LBH589 elevated histone H3 and H4 acetylation. The cell cycle regulators cyclin B, cyclin D1, cdk1 and cdk4 were down-regulated in PC-3, whereas the suppressor proteins p21 and p27 were up-regulated in LNCaP by LBH589. TKI258 up-regulated p27 in PC-3 or p21 in LNCaP and additionally elevated cyclin B, cyclin D1, cdk1 and cdk4 in both cell lines. Presumably, the increase in cyclin and cdk caused by TKI258 counteracts the benefit of p21 or p27 up-regulation, resulting in TKI258 non-responsiveness. The LBH589/TKI258-combination was not superior to the LBH589 single-drug use in terms of growth reduction. Obviously, TKI258 did not enhance the sensitivity of prostate cancer cells towards an HDAC based regimen. Therefore, the LBH589/TKI258-combination probably does not provide an optimum strategy in fighting advanced prostate cancer.

The influence of the bisphosphonate zoledronic acid (ZA) on prostate cancer (PC) growth, adhesion and invasive behavior was investigated.PC-3, DU-145 and LNCaP cells were treated with ZA, and tumor-cell growth was then investigated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Furthermore, tumor-cell adhesion to vascular endothelium or to immobilized extracellular matrix proteins, as well as migratory properties of the cells, was evaluated. Integrin β subtypes, integrin-dependent signaling, as well as cell-cycle regulating proteins, were analyzed by western blots.ZA dose-dependently reduced tumor-cell growth but did not impair tumor-endothelium and tumor-matrix interaction. However, ZA significantly inhibited tumor migration and invasive activity. Cyclin E was reduced by ZA in LNCaP and DU-145, and p21 was elevated in LNCaP cells. p27 was upregulated in all tumor cell lines, compared with the controls. ZA elevated β1-integrin in PC-3 and diminished β4-integrin in PC-3 and DU-145 cells.ZA inhibits PC growth and motility but does not influence the mechanical contact between tumor cells and the vascular wall.

The concept of molecular tumor targeting might provide new hope in the treatment of advanced prostate cancer. We evaluated metastasis blocking properties of the histone deacetylase (HDAC) inhibitor valproic acid (VPA) and the mammalian target of rapamycin (mTOR) inhibitor RAD001 on prostate cancer cell lines. RAD001 or VPA were applied to PC-3 or LNCaP cells, either separately or in combination. Adhesion to vascular endothelium or to immobilized collagen, fibronectin or laminin was quantified. Migration and invasion were explored by a modified Boyden chamber assay. Integrin α and β subtypes were analyzed by flow cytometry, western blotting and RT-PCR. Effects of drug treatment on integrin related signaling, Akt and p70S6kinase activation, histone H3 and H4 acetylation were also determined. Separate application of RAD001 or VPA distinctly reduced tumor cell adhesion, migration and invasion, accompanied by elevated Akt activation and p70S6kinase de-activation. Integrin subtype expression was altered significantly by both compounds (VPA > RAD001). When both drugs were used in concert additive effects were observed on the migratory and invasive behavior but not on tumor-endothelium and tumor-matrix interaction. Separate mTOR or HDAC inhibition slows processes related to tumor metastasis. The RAD001-VPA combination showed advantage over VPA monotreatment with particular respect to migration and invasion. Ongoing studies are required to assess the relevance of VPA monotherapy versus VPA-RAD001 combination on tumor cell motility.

Haematuria is the most common clinical symptom of bladder cancer. Besides antibiotic treatment of a probably existing urinary tract infection, ultrasonography of the urinary organs, diagnostic cystoscopy (with biopsy if needed), and radiologic evaluation of the upper urinary tract (intravenous urography, computed tomography or magnetic resonance urography, retrograde pyelography) should be done for further evaluation. Atypical manifestations of systemic diseases with bladder infiltration could feign the clinical appearance of chronic cystitis and hinder determination of the correct diagnosis. The case of a 40-year-old man with recurrent gross haematuria due to extremely rare bladder infiltration through an IgM plasmacytoma is presented.

Maspin belongs to the serpin family and has been shown to suppress tumor growth and metastasis in several tumor types. The role of maspin in bladder carcinoma has not been fully elucidated, and the object of this study was to investigate whether maspin contributes to bladder tumor adhesion to vascular endothelial cells (HUVEC).Expression of maspin-coding mRNA was evaluated in a panel of bladder carcinoma cell lines. Maspin distribution in maspin mRNA(high) versus maspin mRNA(low) cells was further analyzed by flow cytometry and confocal microscopy. Adhesion to HUVEC was measured in a coculture model and correlated with the surface-bound maspin.Maspin(high) (RT-4, RT-112) cell lines strongly attached to HUVEC, whereas maspin(low) (UMUC-3, MGH-U1) cell lines poorly adhered to HUVEC. Distinct cytoplasmic maspin accumulation and moderate surface-bound maspin was found in RT-4 cells. Blocking maspin surface receptors prevented tumor cell attachment to HUVEC, indicating that surface-bound maspin is responsible for triggering cell adhesion. PMA-triggered elevation of surface-bound maspin was accompanied by an enhanced adhesion capacity of RT-4 cells, compared to controls. Finally, exposing the bladder carcinoma cells to the differentiation-inducing agent valproic acid led to a surface-bound (but not cytoplasmic) maspin decrease, paralleled by a significant reduction in tumor cell binding to HUVEC.Surface-bound maspin directly controls bladder carcinoma cell adhesion to the vascular wall. Blocking this process may prevent transendothelial migration and tumor cell dissemination. Therefore, therapeutic down-regulation of surface-bound maspin might become an option to prevent tumor spread into distant organs.

Konventionelle Masnahmen zur Therapie des fortgeschrittenen Nierenzellkarzinoms (NZK) sind limitiert. Rezeptortyrosinkinaseinhibitoren (RTKI) eroffnen neue Behandlungsoptionen. Wir evaluierten die Wirkung des RTKI AEE788 auf das Wachstum und die Adhasionskapazitat von NZK-Zelllinien in vitro. NZK-Zellen wurden mit AEE788 behandelt und die daraus resultierenden Veranderungen im Wachstumsverhalten sowie die Interaktion mit dem Gefasendothel und Extrazellularmatrixproteinen ermittelt. Es wurde zusatzlich gepruft, ob die gleichzeitige Applikation von Interferon-α (IFN-α) die Effizienz von AEE788 steigern kann. AEE788 fuhrte zu einer signifikanten Hemmung des Tumorzellwachstums und der Adhasion. Rezeptoranalysen ergaben eine Modulation von Integrinproteinen des α- und β-Subtyps sowie eine Hemmung der integrinabhangigen Signalkaskade. Die kombinierte Anwendung von IFN-α und AEE788 bewirkte eine starkere Blockade des Tumorwachstums und der intrazellularen Signalaktivitat, als die alleinige Gabe von AEE788. AEE788 zeigt signifikante antitumorale Eigenschaften, insbesondere in Kombination mit IFN-α, und prasentiert somit eine vielversprechende Substanz zur Behandlung des fortgeschrittenen NZK.

Background Treatment options for metastatic renal cell carcinoma (RCC) are limited due to resistance to chemo- and radiotherapy. The development of small-molecule multikinase inhibitors has now opened novel treatment options. We evaluated the influence of the receptor tyrosine kinase inhibitor AEE788, applied alone or combined with the mammalian target of rapamycin (mTOR) inhibitor RAD001, on RCC cell adhesion and proliferation in vitro. Methods RCC cell lines Caki-1, KTC-26 or A498 were treated with various concentrations of RAD001 or AEE788 and tumor cell proliferation, tumor cell adhesion to vascular endothelial cells or to immobilized extracellular matrix proteins (laminin, collagen, fibronectin) evaluated. The anti-tumoral potential of RAD001 combined with AEE788 was also investigated. Both, asynchronous and synchronized cell cultures were used to subsequently analyze drug induced cell cycle manipulation. Analysis of cell cycle regulating proteins was done by western blotting. Results RAD001 or AEE788 reduced adhesion of RCC cell lines to vascular endothelium and diminished RCC cell binding to immobilized laminin or collagen. Both drugs blocked RCC cell growth, impaired cell cycle progression and altered the expression level of the cell cycle regulating proteins cdk2, cdk4, cyclin D1, cyclin E and p27. The combination of AEE788 and RAD001 resulted in more pronounced RCC growth inhibition, greater rates of G0/G1 cells and lower rates of S-phase cells than either agent alone. Cell cycle proteins were much more strongly altered when both drugs were used in combination than with single drug application. The synergistic effects were observed in an asynchronous cell culture model, but were more pronounced in synchronous RCC cell cultures. Conclusion Potent anti-tumoral activitites of the multikinase inhibitors AEE788 or RAD001 have been demonstrated. Most importantly, the simultaneous use of both AEE788 and RAD001 offered a distinct combinatorial benefit and thus may provide a therapeutic advantage over either agent employed as a monotherapy for RCC treatment.