Nitric oxide (NO) is a potent cell-signaling, effector, and vasodilator molecule that plays important roles in diverse biological effects in the kidney, vasculature, and many other tissues. Because of its high biological reactivity and diffusibility, multiple tiers of regulation, ranging from transcriptional to posttranslational controls, tightly control NO biosynthesis. Interactions of each of the major NO synthase (NOS) isoforms with heterologous proteins have emerged as a mechanism by which the activity, spatial distribution, and proximity of the NOS isoforms to regulatory proteins and intended targets are governed. Dimerization of the NOS isozymes, required for their activity, exhibits distinguishing features among these proteins and may serve as a regulated process and target for therapeutic intervention. An increasingly wide array of proteins, ranging from scaffolding proteins to membrane receptors, has been shown to function as NOS-binding partners. Neuronal NOS interacts via its PDZ domain with several PDZ-domain proteins. Several resident and recruited proteins of plasmalemmal caveolae, including caveolins, anchoring proteins, G protein-coupled receptors, kinases, and molecular chaperones, modulate the activity and trafficking of endothelial NOS in the endothelium. Inducible NOS (iNOS) interacts with the inhibitory molecules kalirin and NOS-associated protein 110 kDa, as well as activator proteins, the Rac GTPases. In addition, protein-protein interactions of proteins governing iNOS transcription function to specify activation or suppression of iNOS induction by cytokines. The calpain and ubiquitin-proteasome pathways are the major proteolytic systems responsible for the regulated degradation of NOS isozymes. The experimental basis for these protein-protein interactions, their functional importance, and potential implication for renal and vascular physiology and pathophysiology is reviewed.

The ability of cancer cells to invade along nerves is associated with aggressive disease and diminished patient survival rates. Perineural invasion (PNI) may be mediated by nerve secretion of glial cell line-derived neurotrophic factor (GDNF) attracting cancer cell migration through activation of cell surface Ret proto-oncogene (RET) receptors. GDNF family receptor (GFR)α1 acts as coreceptor with RET, with both required for response to GDNF. We demonstrate that GFRα1 released by nerves enhances PNI, even in the absence of cancer cell GFRα1 expression. Cancer cell migration toward GDNF, RET phosphorylation, and MAPK pathway activity are increased with exposure to soluble GFRα1 in a dose-dependent fashion. Dorsal root ganglia (DRG) release soluble GFRα1, which potentiates RET activation and cancer cell migration. In vitro DRG coculture assays of PNI show diminished PNI with DRG from GFRα1 +/− mice compared with GFRα1 +/+ mice. An in vivo murine model of PNI demonstrates that cancer cells lacking GFRα1 maintain an ability to invade nerves and impair nerve function, whereas those lacking RET lose this ability. A tissue microarray of human pancreatic ductal adenocarcinomas demonstrates wide variance of cancer cell GFRα1 expression, suggesting an alternate source of GFRα1 in PNI. These findings collectively demonstrate that GFRα1 released by nerves enhances PNI through GDNF-RET signaling and that GFRα1 expression by cancer cells enhances but is not required for PNI. These results advance a mechanistic understanding of PNI and implicate the nerve itself as a key facilitator of this adverse cancer cell behavior.

This paper presents a unified calculation method and its application in determining the uniaxial mechanical properties of concrete with concrete strengths ranging from 10 to 140 MPa. By analyzing a large collection of test results of the uniaxial mechanical properties of normal-strength, high-strength and super high-strength concrete in China and performing a regression analysis, unified calculation formulas for the mechanical indexes of concrete are proposed that can be applied to various grades of concrete for determining the size coefficient, uniaxial compressive strength, uniaxial tensile strength, elastic modulus, and strain at peak uniaxial compression and tension. Optimized mathematical equations for the nonlinear stress-strain relationship of concrete, including the ascending and descending branches under uniaxial stress, are also established. The elastic modulus is almost constant throughout the elastic stage for the ascending branches of the stress-strain relationship for concrete. The proposed stress-strain relationship of concrete was applied to the nonlinear finite element analysis of both a steel-concrete composite beam and a concrete-filled steel tubular stub column. The analytical results are in good agreement with the experiment results, indicating that the proposed stress-strain relationship of concrete is applicable. The achievements presented in this paper can be used as references for the design and nonlinear finite element analysis of concrete structures.

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Malignant pleural mesothelioma (MPM) is a fatal disease with a median survival of less than 14 months. For the first time, a genetically engineered vaccinia virus is shown to produce efficient infection, replication, and oncolytic effect against MPM. GLV-1h68 is a replication-competent engineered vaccinia virus carrying transgenes encoding Renilla luciferase, green fluorescent protein (both inserted at the F14.5L locus), beta-galactosidase (inserted at the J2R locus, which encodes thymidine kinase), and beta-glucuronidase (at the A56R locus, which encodes hemagglutinin). This virus was tested in six human MPM cell lines (MSTO-211H, VAMT, JMN, H-2373, H-2452, and H-2052). GLV-1h68 successfully infected all cell lines. For the most sensitive line, MSTO-211H, expression of green fluorescent protein (GFP) started within 4 hr with increasing intensity over time until nearly 100% of cells expressed GFP at 24 hr. All cell lines were sensitive to killing by GLV-1h68, with the degree of sensitivity predictable by infectivity assay. Even the most resistant cell line exhibited 44 +/- 3.8% cell survival by day 7 when infected at a multiplicity of infection of 1.0. Viral proliferation assays demonstrated 2-to 4-fold logarithmic replication of GLV-1h68 in the cell lines tested. In an orthotopic model, GLV-1h68 effectively prevented development of cachexia and tumor-related morbidity, reduced tumor burden, and cured MPM in both early and late treatment groups. GLV-1h68 was successfully used to treat MPM in vitro and in an orthotopic model (in vivo). These promising results warrant clinical investigation of GLV-1h68 as a novel agent in the treatment of MPM.

Perineural invasion (PNI) is a form of cancer progression where cancer cells invade along nerves. This behavior is associated with poor clinical outcomes; therefore, it is critical to identify novel ligand-receptor interactions between nerves and cancer cells that support the process of PNI. A proteomic profiler chemokine array was used to screen for nerve-derived factors secreted from tissue explants of dorsal root ganglion (DRG), and CCL2 was identified as a lead candidate. Prostate cancer cell line expression of CCR2, the receptor to CCL2, correlated closely with MAPK and Akt pathway activity and cell migration towards CCL2 and DRG. In vitro nerve and cancer co-culture invasion assays of PNI demonstrated that cancer cell CCR2 expression facilitates PNI. PNI is significantly diminished in co-culture assays when using DRG harvested from CCL2−/− knockout mice as compared with control CCL2+/+ mice, indicating that CCR2 is required for PNI in this murine model of PNI. Furthermore, 20/21 (95%) of patient specimens of prostate adenocarcinoma with PNI exhibited CCR2 expression by immunohistochemistry, while just 3/13 (23%) lacking PNI expressed CCR2. In summary, nerve-released CCL2 supports prostate cancer migration and PNI though CCR2-mediated signaling.

Oncolytic viruses based on herpes simplex virus type 1 (HSV-1) are able to infect and lyse a variety of malignant cell lines. However, there is variability in the degree of tumor susceptibility, and the cancer cell determinants of HSV sensitivity are poorly defined. Nectin-1 is a cell surface adhesion molecule that functions as a cellular receptor to HSV envelope glycoprotein D (gD). We assessed tumor nectin-1 expression as a predictor of oncolytic HSV sensitivity. A panel of human squamous carcinoma cell lines was evaluated for viral entry, replication, and cytotoxicity to an attenuated, replication-competent, oncolytic HSV (NV1023). Potential tumor determinants of HSV sensitivity were assessed, including nectin-1, herpes viral entry mediator, total gD receptor expression, S-phase fraction, and doubling time. Significant correlations between nectin-1 expression measured by quantitative fluorescence-activated cell sorting and viral sensitivity measures were identified using Pearson's coefficients. Cancer cell nectin-1 receptor blockade and nectin-1 transfection led to inhibition and enhancement of NV1023 viral entry, respectively. Cell lines with varying nectin-1 expression showed corresponding sensitivity to NV1023 therapy in vivo. Immunohistochemistry for nectin-1 was inversely related to E-cadherin staining, suggesting increased herpes sensitivity of E-cadherin-deficient tumors. These results suggest that nectin-1 may be used as a marker to predict the sensitivity of a tumor to herpes oncolytic therapy.

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