from the tissue-culture flasks with 0.05% trypsin, 0.02% EDTA, and 0.1% glucose in PBS for 2 min at 37°C. Electron microscopyCell suspensions were fixed for 10 min at room temperature in 2% glutaraldehyde in PBS. After rinsing with PBS, the cell pellet was resuspended at 37°C in 10% gelatin solution and centrifuged for 4 min at 4300 g. After solidifying of the gelatin, cells were post-fixed in 1% OsO, in Palade buffer, PH-7.3, dehydrated in ethanol, treated with propylene oxide and embedded in epoxy resin. Ultra-thin sections were obtained, stained with uranylacetate solution, and examined using a Philips 200 electron microscope. Immunocytochemistry and monoclonal antibodiesCultures of MV3 cells were detached from culture flasks. Cell suspensions were washed 3 times with PBS containing 3% MATERIAL AND METHODS Clinical and pathological dataA 76-year-old male patient suffered from a primary cutaneous amelanotic malignant melanoma of the chin region (nod-3To whom correspondence and reprint requests should be addressed, at

Results provide evidence for the location of TRPV4 in human bladder urothelium. TRPV4 is molecularly connected to adherence junctions on the urothelial cell membrane. TRPV4 coupling to a rigid intracellular and intercellular structural network would agree with the hypothesis that TRPV4 can be activated by bladder stretch.

This study reveals an important role for chondroitin sulfate in bladder barrier function. Therapies aiming at restoring the luminal glycosaminoglycan layer in pathological conditions such as bladder pain syndrome/interstitial cystitis are based on a sound principle.

We compared integrin‐mediated adhesion to extracellular matrix (ECM) components of cultured human melanocytes and 6 human melanoma cell lines with different metastatic capacities in nude mice. Cultured melanocytes and most melanoma cell lines adhered strongly to fibronectin (FN), whereas only highly metastatic cell lines adhered to laminin (LM), collagen type I (COI) and type IV (COIV). Adhesion to LM and CO could be blocked by anti‐α6 and anti‐α2 monoclonal antibodies (MAbs) respectively. This observation is consistent with the finding that expression of LM receptor α6β1 and LM/CO receptor α2β1 was low on melanocytes and non‐ or poorly metastatic cell lines, whereas these integrins were strongly expressed on highly metastatic cell lines. In addition, immunoprecipitation from [35S]‐methionine‐labeled cells demonstrated increased synthesis of α6, α2 and β1 in highly metastatic cell lines and immunohis‐tochemistry showed expression of α6β1 and α2β1 only in xenograft lesions from highly metastatic cell lines. Furthermore, the observation that adhesion of melanocytes and non‐ or poorly metastatic cell lines could be stimulated with anti β1 MAbs demonstrates that these receptors, on these cells, are expressed in an inactive state. Our results suggest that α2β1 and α6β1 play a role in human melanoma metastasis in nude mice and demonstrate that interactions of these integrins with their ligands can be regulated at the level of surface expression and activation state of the receptor.

Significance The human prostate accumulates high luminal citrate levels to serve sperm viability. There is only indirect qualitative evidence about metabolic pathways and carbon sources maintaining these levels. Human citrate-secreting prostate cancer cells were supplied with 13 C-labeled substrates, and NMR spectra of extracellular fluid were recorded. We report absolute citrate production rates of prostate cells and direct evidence that glucose is the main carbon source for secreted citrate. Pyruvate carboxylase provides sufficient anaplerotic carbons to support citrate secretion. Glutamine carbons exchange with carbons for secreted citrate but are likely not involved in its net synthesis. Moreover, we developed metabolic models employing the 13 C distribution in extracellular citrate as input to assess intracellular pathways followed by carbons toward citrate.