Vascular niche IL-6 induces alternative macrophage activation in glioblastoma through HIF-2α.

Spatiotemporal regulation of tumor immunity remains largely unexplored. Here we identify a vascular niche that controls alternative macrophage activation in glioblastoma (GBM). We show that tumor-promoting macrophages are spatially proximate to GBM-associated endothelial cells (ECs), permissive for angiocrine-induced macrophage polarization. We identify ECs as one of the major sources for interleukin-6 (IL-6) expression in GBM microenvironment. Furthermore, we reveal that colony-stimulating factor-1 and angiocrine IL-6 induce robust arginase-1 expression and macrophage alternative activation, mediated through peroxisome proliferator-activated receptor-γ-dependent transcriptional activation of hypoxia-inducible factor-2α. Finally, utilizing a genetic murine GBM model, we show that EC-specific knockout of IL-6 inhibits macrophage alternative activation and improves survival in the GBM-bearing mice. These findings illustrate a vascular niche-dependent mechanism for alternative macrophage activation and cancer progression, and suggest that targeting endothelial IL-6 may offer a selective and efficient therapeutic strategy for GBM, and possibly other solid malignant tumors

Diagnostic utility of aberrant methylation of tissue factor pathway inhibitor 2 in pure pancreatic juice for pancreatic carcinoma

医薬保健研究域医学系The tissue factor pathway inhibitor 2 (TFPI-2) is a Kunitz-type serine proteinase inhibitor. Recently, the aberrant methylation of TFPI-2 was detected frequently in pancreatic carcinoma (PCa) tissues but not in normal pancreatic tissues. We analyzed the aberrant methylation of TFPI-2 in the pure pancreatic juice (PPJ) aspirated endoscopically from patients with various pancreatic diseases. Using the highly sensitive methylation-specific polymerase chain reaction (MSP) and quantitative MSP (Q-MSP) assay, we investigated the aberrant methylation of TFPI-2 in nine human PCa cell lines and in the PPJ from patients with PCa, intraductal papillary mucinous neoplasms (IPMN) and chronic pancreatitis (CP). The incidence of aberrant TFPI-2 methylation was seven (77.8%) of nine PCa cell lines by Q-MSP. In cell lines, the expression of TFPI-2 mRNA by quantitative reverse transcription-polymerase chain reaction showed an inverse correlation to the aberrant methylation of TFPI-2. The incidence of aberrant TFPI-2 methylation in the PPJ was 21 (58.3%) of 36 PCa patients, three (17.6%) of 17 IPMN and one (4.8%) of 21 CP by MSP assay. Using a suitable cut-off value of 2.5 according to the receiver operating characteristic curve, the incidence of aberrant TFPI-2 methylation in the PPJ by real-time MSP was 18 (62.1%) of 29 PCa patients, one (5.1%) of 17 IPMN and three (14.3%) of 21 CP, respectively. The incidence of quantitative TFPI-2 hypermethylation in the PPJ with PCa was significantly higher than that with IPMN (P < 0.001) or CP (P < 0.001). Moreover, the aberrant methylation rate of TFPI-2 in the PPJ was 100%, as observed (6/6) in the PCa patients with liver metastasis, and 86.7% (26/30) in stages IVa + IVb of PCa by Q-MSP assay. These results suggest that promoter methylation of TFPI-2 in the PPJ may be a useful marker in the diagnosis and progression of PCa using an endoscopically feasible approach. © 2006 Japanese Cancer Association

Genipin-cross-linked collagen/chitosan biomimetic scaffolds for articular cartilage tissue engineering applications

This was the first study to use genipin to cross-link collagen and chitosan.In this study, genipin-cross-linked collagen/chitosan biodegradable porous scaffolds were prepared for articular cartilage regeneration. The influence of chitosan amount and genipin concentration on the scaffolds physicochemical properties was evaluated. The morphologies of the scaffolds were characterized by scanning electron microscope (SEM) and cross-linking degree was investigated by ninhydrin assay. Additionally, the mechanical properties of the scaffolds were assessed under dynamic compression. To study the swelling ratio and the biostability of the collagen/chitosan scaffold, in vitro tests were also carried out by immersion of the scaffolds in PBS solution or digestion in collagenase, respectively. The results showed that the morphologies of the scaffolds underwent a fiber-like to a sheet-like structural transition by increasing chitosan amount. Genipin cross-linking remarkably changed the morphologies and pore sizes of the scaffolds when chitosan amount was less than 25%. Either by increasing the chitosan ratio or performing cross-linking treatment, the swelling ratio of the scaffolds can be tailored. The ninhydrin assay demonstrated that the addition of chitosan could obviously increase the cross-linking efficiency. The degradation studies indicated that genipin cross-linking can effectively enhance the biostability of the scaffolds. The biocompatibility of the scaffolds was evaluated by culturing rabbit chondrocytes in vitro. This study demonstrated that a good viability of the chondrocytes seeded on the scaffold was achieved. The SEM analysis has revealed that the chondrocytes adhered well to the surface of the scaffolds and contacted each other. These results suggest that the genipin-cross-linked collagen/chitosan matrix may be a promising formulation for articular cartilage scaffolding.Key Projects in the National Science and Technology Pillar Program in the Eleventh Five-year Plan Period. Grant Number: 2006BA116B04Guangdong Natural Science Foundation. Grant Number: 07300602Natural Science Foundation Team Project of Guangdong. Grant Number: 4205786State Key Program of National Natural Science of China. Grant Number: 50732003National Basic Research Program of China. Grant Number: 2005CB62390

Phytochemical and bioactivity investigations of three invasive neophytes Buddleja davidii Franch (Buddlejaceae), Polygonum cuspidatum Sieb. & Zucc. and Polygonum sachalinensis F. Schmidt ex Maxim (Nakai) (Polygonaceae)

This work aimed to reveal the invasive mechanism of invasiv plant species and to study their beneficial uses. An acetylcholinesterase inhibitor linarin was isolated from Buddleja davidii Franch (Buddlejaceae), and the structure-activity relationship was studied. HPLC/UV/ESI-MS analyses demonstrated different phytochemcial profiles of Polygonum cuspidatum Sieb. & Zucc. and P. sachalinensis F. Schmidt ex Maxim (Polygonaceae) from China and Switzerland. Seven compounds of 21 isolated compounds were reported for the first time from these two species. Allelopathy tests revealed strong phytotoxicity of the leaf and root extracts, and discovered two strong allelochemicals resveratrol and rhein, as well as piceid, resveratroloside or piceatannol glucoside with stronger activity than (-) - catechin. Other biotests showed the potential of the isolated compounds against α-glucosidase, aromatase or as anti-inflammatory agents. At last the total content of resveratrol in the invasive Swiss variety of P. cuspidatum was measured to prove it a source of resveratrol

Cannabisin F from Hemp (<i>Cannabis sativa</i>) Seed Suppresses Lipopolysaccharide-Induced Inflammatory Responses in BV2 Microglia as SIRT1 Modulator

Hemp seed (Fructus cannabis) is rich in lignanamides, and initial biological screening tests showed their potential anti-inflammatory and anti-oxidative capacity. This study investigated the possible effects and underlying mechanism of cannabisin F, a hempseed lignanamide, against inflammatory response and oxidative stress in lipopolysaccharide (LPS)-stimulated BV2 microglia cells. Cannabisin F suppressed the production and the mRNA levels of pro-inflammatory mediators such as interleukin 6 (IL-6) and tumor necrosis factor &#945; (TNF-&#945;) in a concentration-dependent manner in LPS-stimulated BV2 microglia cell. Furthermore, cannabisin F enhanced SIRT1 expression and blocked LPS-induced NF-&#954;B (Nuclear factor kappa B) signaling pathway activation by inhibiting phosphorylation of I&#954;B&#945; (Inhibit proteins of nuclear factor kappaB) and NF-&#954;B p65. And the SIRT1 inhibitor EX527 significantly inhibited the effect of cannabisin F on pro-inflammatory cytokines production, suggesting that the anti-inflammatory effects of cannabisin F are SIRT1-dependent. In addition, cannabisin F reduced the production of cellular reactive oxygen species (ROS) and promoted the expression of Nrf2 (Nuclear factor erythroid-2 related factor 2) and HO-1 (Heme Oxygenase-1), suggesting that the anti-oxidative effects of cannabisin F are related to Nrf2 signaling pathway. Collectively, these results suggest that the neuro-protection effect of cannabisin F against LPS-induced inflammatory response and oxidative stress in BV2 microglia cells involves the SIRT1/NF-&#954;B and Nrf2 pathway

Anti-inflammatory Activity of the Invasive Neophyte Polygonum Cuspidatum Sieb. and Zucc. (Polygonaceae) and the Chemical Comparison of the Invasive and Native Varieties with regard to Resveratrol

Polygonum cuspidatum Sieb. and Zucc. has been traditionally used as a member of many anti-inflammatory polyherbal formulations, but is now a widespread invasive neophyte in Europe and America. To discuss if the invasive variety is chemically identical to the native one in traditional medicine, the different constituents of the invasive variety compared to the native variety were isolated and their anti-inflammatory activity was tested. Resveratroloside and catechin-(4α→8)-catechin, the newly found constituents in the invasive variety, have similar nitric oxide (NO) inhibition potency as that of piceid (the major constituent of P. cuspidatum), but the newly found major constituent, i.e., piceatannol glucoside, showed no apparent effect. On the other hand, as a marker, the total content of resveratrol in the methanol root extract after glucosidase hydrolysis was measured and compared between the invasive and native varieties. The total content of resveratrol measured in the root extracts of the Swiss sample was about 2.5 times less than that of the Chinese one. This study brings attention to the point that when the invasive variety of P. cuspidatum is used in traditional medicine, the chemical difference should be kept in mind

Acetylcholinesterase-Inhibitory Activity of Linarin from Buddleja davidii, Structure-Activity Relationships of Related Flavonoids, and Chemical Investigation of Buddleja nitida

In order to find some medicinal value for invasive neophytes, inhibition of acetylcholinesterase of Reynoutria sachalinensis F. Schmidt ex Maxim. (Polygonaceae), Polygonum cuspidatum Siebold. Zucc. (Polygonaceae), Heracleum mantegazzianum Sommier Levier (Apiaceae), Buddleja davidii Franch. (Buddlejaceae), and Ambrosia artemisiifolia L. (Asteraceae) was prescreened by a bioautographic TLC assay. Activity was found in the methanol extract of the leaves of the common ornamental bush B. davidii. Its fractionation by centrifugal partition chromatography led to the isolation of linarin as the most active compound. While extracts of Buddleja nitida Benth. (Buddlejaceae) from Panama were inactive, some constituents were identified on the basis of a comparison with B. davidii by HPLC-MS/MS. Structure-activity relationships of linarin and related flavonoids were investigated. For this purpose, fortunellin and tilianin were prepared by methylation reactions. It appears that the structural elements important for acetylcholinesterase inhibition are not only the 4' -OMe group, but also the 7-substituted sugar and the pattern of substitution on the B-ring