Resveratrol (Res), a natural polyphenolic compound, has anticancer activity in a variety of cancers. In the present study, the antitumor effect and underlying molecular mechanism of Res on rat C6 glioma growth was studied. The results demonstrated that Res inhibited glioma cell proliferation, arrested cell cycle in S phase and induced apoptosis in vitro. Res also suppressed intracranial C6 tumor growth in vivo and prolonged survival in a fraction of the rats bearing intracranial gliomas. Res significantly downregulated the specific miRs, including miR-21, miR-30a-5p and miR-19, which have been identified as oncomiRs in our previous studies, and altered the expression of their targeting and crucial genes for glioma formation and progression such as p53, PTEN, EGFR, STAT3, COX-2, NF-κB and PI3K/AKT/mTOR pathway. Therefore, the anti-glioma effect of Res, at least in part, is through the regulation of oncogenic miRNAs. The effect of Res on non-coding RNAs should be studied further. Res is a potential multi-targeting drug for the treatment of gliomas.

Epithelial-to-mesenchymal transition (EMT) enables metastasis. E-cadherin loss is a hallmark of EMT, but there remains an incomplete understanding of the epigenetics of this process. The protein arginine methyltransferase PRMT7 functions in various physiologic processes, including mRNA splicing, DNA repair, and neural differentiation, but its possible roles in cancer and metastasis have not been explored. In this report, we show that PRMT7 is expressed at higher levels in breast carcinoma cells and that elevated PRMT7 mediates EMT and metastasis. PRMT7 could inhibit the expression of E-cadherin by binding to its proximal promoter in a manner associated with altered histone methylation, specifically with elevated H4R3me2s and reduced H3K4me3, H3Ac, and H4Ac, which occurred at the E-cadherin promoter upon EMT induction. Moreover, PRMT7 interacted with YY1 and HDAC3 and was essential to link these proteins to the E-cadherin promoter. Silencing PRMT7 restored E-cadherin expression by repressing H4R3me2s and by increasing H3K4me3 and H4Ac, attenuating cell migration and invasion in MDA-MB-231 breast cancer cells. Overall, our results define PRMT7 as an inducer of breast cancer metastasis and present the opportunity for applying PRMT7-targeted therapeutics to treat highly invasive breast cancers. Cancer Res; 74(19); 5656–67. 2014 AACR.

Objective To study the potential of high-dose N-acetylcysteine (NAC) to attenuate silica-induced pulmonary fibrosis in the rat. Methods Rats exposed to intratracheal instillation of silica particles were treated with 500 mg/kg NAC orally every day for 7 days, before and up to 28 days after silica administration ( n = 32), or received no treatment following silica exposure ( n = 32); a third group received intratracheal saline ( n = 32). Fibrosis score, and hydroxyproline (HYP) and malondialdehyde (MDA) content, were assessed in lung tissue. Bronchoalveolar lavage fluid (BALF) and serum levels of tumour necrosis factor (TNF)-α, interleukin (IL)-8 and high-sensitivity C-reactive protein (hsCRP) were assessed by enzyme-linked immunosorbent assay. Results Histopathology revealed inflammation and fibrosis in lung tissue from rats exposed to silica, but not in saline controls. The fibrosis score was significantly lower in animals treated with NAC compared with silica-exposed untreated rats. HYP and MDA content were significantly lower at all timepoints, following NAC treatment versus no treatment, in silica-exposed rats. NAC attenuated silica-induced increases in TNF-α, IL-8 and hsCRP in BALF and serum. Conclusions Oral treatment with high-dose NAC during early silica exposure can ameliorate the activity of proinflammatory cytokines, thus attenuating subsequent lung fibrosis. These results suggest that NAC has potential as a treatment for silica-induced lung fibrosis.

Objective. Our previous studies have demonstrated the efficacy of resveratrol, a grape constituent noted for its antioxidant and anti-inflammatory properties, in reducing temporary threshold shifts and decreasing cochlear hair cell damage following noise exposure. This study was designed to identify the potential protective mechanism of resveratrol by measuring its effect on cyclooxygenase-2 (COX-2) protein expression and reactive oxygen species (ROS) formation following noise exposure.Study Design. Controlled animal intervention study.Setting. Otology Laboratory, Henry Ford Health System.Subjects and Methods. Twenty-two healthy male Fischer 344 rats (2-3 months old) were exposed to acoustic trauma of variable duration with or without intervention. An additional 20 healthy male rats were used to study COX-2 expression at different time points during and following treatment of 24 hours of noise exposure. Cochlear harvest was performed at various time intervals for measurement of COX-2 protein expression via Western blot analysis and immunostaining. Peripheral blood was also obtained for ROS analysis using flow cytometry.Results. Acoustic trauma exposure resulted in a progressive up-regulation of COX-2 protein expression, commencing at 8 hours and peaking at 32 hours. Similarly, ROS production increased after noise exposure. However, treatment with resveratrol reduced noise-induced COX-2 expression as well as ROS formation in the blood as compared with the controls.Conclusion. COX-2 levels are induced dramatically following noise exposure. This increased expression may be a potential mechanism of noise-induced hearing loss (NIHL) and a possible mechanism of resveratrol's ability to mitigate NIHL by its ability to reduce COX-2 expression.

A new series of isoxazole derivatives, N-phenyl-5-carboxamidyl isoxazoles, was investigated for their anticancer activity with solid tumor selectivity. Six N-phenyl-5-carboxamidylisoxazoles were chemically synthesized and evaluated by the in vitro disk-diffusion assay and IC50 cytotoxicity determination. The results showed that one of the derivatives, compound 3,N-(4-chlorophenyl)-5-carboxamidyl isoxazole, was the most active against colon 38 and CT-26 mouse colon tumor cells with an IC50 of 2.5 μg/mL for both cell lines. Western blot analysis showed that compound 3 significantly down-regulated the expression of phosphorylated STAT3 in both human and mouse colon cancer cells indicating that the mechanism of action for compound 3 may involve the inhibition of JAK3/STAT3 signaling pathways. Flow cytometric analysis with Annexin V staining showed that the death induced by compound 3 is mediated through cell necrosis and not apoptotic pathway. In summary, our results show that compound 3 is a new N-phenyl-5-carboxamidyl isoxazole with potential anticancer activity. Compound 3 inhibits the phosphorylation of STAT3, a novel target for chemotherapeutic drugs, and is worthy of further investigation as a potential chemotherapeutic agent for treating colon cancer.

a Neuropharmacology, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China b Zhongshan ophthalmic center, Sun Yat-sen University, Guangzhou, China c Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel d Department of Neurology, Henry Ford Hospital, Detroit, MI, USA e Department of Anesthesiology, State University of New York — Downstate Medical Center, Brooklyn, NY, USA

Modifications in signaling of the proline-rich Akt substrate of 40-kDa (PRAS40) pathway is implicated in type 2 diabetes and melanoma. PRAS40 is known for its ability to regulate the mammalian target of rapamycin complex 1 (mTORC1) kinase activity, possessing a key regulatory role at the cross point of signal transduction pathways activated by growth factor receptors. Recently it has been found that PRAS40 is regulated by its upstream phosphatidylinositol 3-kinase/Akt (PI3K/Akt) which is activated by many tyrosine kinase receptors growth factors including insulin-like growth factor 1. Also, PRAS40 functions downstream of mTORC1 and upstream from its effectors ribosomal protein S6 kinase 1 (S6K1) and eukaryotic initiation factor 4E binding protein 1 (4E-BP1). Phosphorylation of PRAS40 by Akt and mTORC1 disrupts the binding between mTORC1 and PRAS40, and relieves the inhibitory constraint of PRAS40 on mTORC1 activity. This review summarizes the signaling regulating PRAS40 phosphorylation, as well as the dual function of PRAS40 as substrate and inhibitor of mTORC1 upon growth factor stimulation and under pathophysiological conditions.

Pituitary adenylate cyclase activating peptide (PACAP), a potent neuropeptide which crosses the blood–brain barrier, is known to provide neuroprotection in rat stroke models of middle cerebral artery occlusion (MCAO) by mechanism(s) which deserve clarification. We confirmed that following i.v. injection of 30 ng/kg of PACAP38 in rats exposed to 2 h of MCAO focal cerebral ischemia and 48 h reoxygenation, 50 % neuroprotection was measured by reduced caspase-3 activity and volume of cerebral infarction. Similar neuroprotective effects were measured upon PACAP38 treatment of oxygen–glucose deprivation and reoxygenation of brain cortical neurons. The neuroprotection was temporally associated with increased expression of brain-derived neurotrophic factor, phosphorylation of its receptor—tropomyosin-related kinase receptor type B (trkB), activation of phosphoinositide 3-kinase and Akt, and reduction of extracellular signal-regulated kinases 1/2 phosphorylation. PACAP38 increased expression of neuronal markers beta-tubulin III, microtubule-associated protein-2, and growth-associated protein-43. PACAP38 induced stimulation of Rac and suppression of Rho GTPase activities. PACAP38 downregulated the nerve growth factor receptor (p75 NTR ) and associated Nogo-(Neurite outgrowth-A) receptor. Collectively, these in vitro and in vivo results propose that PACAP exhibits neuroprotective effects in cerebral ischemia by three mechanisms: a direct one, mediated by PACAP receptors, and two indirect, induced by neurotrophin release, activation of the trkB receptors and attenuation of neuronal growth inhibitory signaling molecules p75 NTR and Nogo receptor.

The catalytic and regulatory subunits of class I phosphoinositide 3-kinase (PI3K) have oncogenic potential. The catalytic subunit p110α and the regulatory subunit p85 undergo cancer-specific gain-of-function mutations that lead to enhanced enzymatic activity, ability to signal constitutively, and oncogenicity. The β, γ, and δ isoforms of p110 are cell-transforming as overexpressed wild-type proteins. Class I PI3Ks have the unique ability to generate phosphoinositide 3,4,5 trisphosphate (PIP3). Class II and class III PI3Ks lack this ability. Genetic and cell biological evidence suggests that PIP3 is essential for PI3K-mediated oncogenicity, explaining why class II and class III enzymes have not been linked to cancer. Mutational analysis reveals the existence of at least two distinct molecular mechanisms for the gain of function seen with cancer-specific mutations in p110α; one causing independence from upstream receptor tyrosine kinases, the other inducing independence from Ras. An essential component of the oncogenic signal that is initiated by PI3K is the TOR (target of rapamycin) kinase. TOR is an integrator of growth and of metabolic inputs. In complex with the raptor protein (TORC1), it controls cap-dependent translation, and this function is essential for PI3K-initiated oncogenesis.

Nuclear translocation of Forkhead transcription factors of the O class (FoxOs) is important for the action of growth factors. However it is not known if all members of the FOXO family have the same translocation properties. We examined the effects of nerve growth factor (NGF) on nuclear/cytoplasmic shuttling of FoxO1, FoxO3a and FoxO6 in PC12 cells and determined their translocation kinetics. Our data demonstrated that NGF could induce the nuclear exclusion of FoxO1-GFP and FoxO3a-GFP in PC12 cells with different properties, but had no effect on FoxO6-GFP's nuclear localization and FoxO6-GFP showed an exclusive nuclear localization. Translocat ould be blocked by K252a and LY294002 but not by PD98059. Moreover, FoxO3a returned to cytoplasm at a higher rate than FoxO1 after NGF stimulation and it was more sensitive than FoxO1 to NGF stimulation.

We demonstrate that tissue plasminogen activator (tPA) and its inhibitors contribute to neurite outgrowth in the central nervous system (CNS) after treatment of stroke with multipotent mesenchymal stromal cells (MSCs). In vivo, administration of MSCs to mice subjected to middle cerebral artery occlusion (MCAo) significantly increased activation of tPA and downregulated PAI-1 levels in the ischemic boundary zone (IBZ) compared with control PBS treated mice, concurrently with increases of myelinated axons and synaptophysin. In vitro, MSCs significantly increased tPA levels and concomitantly reduced plasminogen activator inhibitor 1 (PAI-1) expression in astrocytes under normal and oxygen and glucose deprivation (OGD) conditions. ELISA analysis of conditioned medium revealed that MSCs stimulated astrocytes to secrete tPA. When primary cortical neurons were cultured in the conditioned medium from MSC co-cultured astrocytes, these neurons exhibited a significant increase in neurite outgrowth compared to conditioned medium from astrocytes alone. Blockage of tPA with a neutralizing antibody or knock-down of tPA with siRNA significantly attenuated the effect of the conditioned medium on neurite outgrowth. Addition of recombinant human tPA into cortical neuronal cultures also substantially enhanced neurite outgrowth. Collectively, these in vivo and in vitro data suggest that the MSC mediated increased activation of tPA in astrocytes promotes neurite outgrowth after stroke.

Resveratrol is a naturally occurring polyphenolic compound highly enriched in grapes, peanuts, red wine, and a variety of food sources. Sulforaphane belongs to the family of isothiocyanates and is highly enriched in cruciferous vegetables. Our previous study showed that resveratrol, when used at high concentrations, inhibited cell proliferation, caused the cell cycle arrest and induced apoptotic cell death in glioma cells. In the current study, we tested the effect of combination treatment with resveratrol and sulforaphane, when both were used at low concentrations, on cell proliferation, migration and death in human U251 glioma cells. Our study shows that combination treatment with resveratrol and sulforaphane inhibits cell proliferation and migration, reduces cell viability, induces lactate dehydrogenase release, decreases pro-survival Akt phosphorylation and increases caspase-3 activation. The use of combination of bioactive food components, such as resveratrol and sulforaphane, may be a viable approach for the treatment of glioma.

Our previous study demonstrated that SEPT7 was downregulated at mRNA level in human gliomas. This study is to further examine the expression of SEPT7 in glioma samples and characterizes its role on cell cycle progression and growth of glioma cells. mRNA and protein expression of SEPT7 were detected by RT-PCR, immunohistochemical staining, and western blot analysis in human glioma specimens and normal brain tissues. A pcDNA3-SEPT7 expression plasmid was constructed and transfected into human glioblastoma cell line U251, and cell proliferation and apoptosis were examined. The growth of established U251 and TJ905 subcutaneous xenograft gliomas was measured in nude mice treated with pcDNA3-SEPT7 and U251 xenograft tumors treated with SEPT7 siRNA. SEPT7 expression is negatively correlated with the increase of glioma grade. Overexpression of SEPT7 is able to inhibit cell proliferation and arrest cell cycle progression in the G0/G1 phase both in vitro and in vivo. Knocking down further the already low endogenous expression of SEPT7 in U251 xenograft tumors with siRNA leads to faster tumor growth compared with control tumors. This study demonstrates that SEPT7 is involved in gliomagenesis and suppresses glioma cell growth.

Aberrant Wnt/β-catenin signaling contributes to the development of many cancers, including glial tumorigenesis. While cross talk between the Wnt/β-catenin and PI3K/AKT signaling pathways has been proposed, the impact of PI3K/AKT inhibition on β-catenin signaling in glioma remains unknown. In the present study, we report decreased cell proliferation and invasive ability upon the LY294002-induced inhibition of PI3K in both U251 and LN229 human glioblastoma cells in vitro. Pharmacologic inhibition of PI3K resulted in the downregulation of several members of the β-catenin pathway, including Fra-1, c-Myc, and cyclin D1. Downregulation impacted β-catenin-mediated transcription, as LY294002 decreased β-catenin/TCF transcriptional activity, determined by the reporter assay. Similar results were observed in vivo, as intratumoral injection of LY294002 downregulated the expression of the components of the β-catenin pathway and delayed tumor growth in nude mice harboring subcutaneous LN229 xenografts. These results suggest that the PI3K/AKT signaling pathway regulates glioma cell proliferation, in part via repression of the Wnt/β-catenin pathway.

Promotion of apoptosis in cancer cells could potentially lead to the regression and improved prognosis of hormone-refractory prostate cancer. Xanthohumol (XN), a prenylated chalcone-derived from hops, has shown strong antitumorigenic activity towards diverse types of cancer cells. In the present study, the growth-inhibitory and apoptosis-inducing activity of XN was tested in hormone-sensitive and hormone-refractory human prostate cancer cells lines. Cell growth/viability assay (MTS) demonstrated that prostate cancer cells are highly sensitive to XN at a concentration range of 20-40 μM. The primary mode of tumor cell destruction was apoptosis as demonstrated by the binding of annexin V-FITC, cleavage of PARP-1, activation of procaspases -3, -8, and -9, mitochondrial depolarization and release of cytochrome c from mitochondria. Induction of apoptosis by XN was associated with the inhibition of prosurvival Akt, NF-κB and mTOR signaling proteins and NF-κB-regulated anti-apoptotic Bcl-2 and survivin. These studies provide a rationale for clinical evaluation of XN for the treatment of hormone-refractory metastatic prostate cancer.

OBJECT The authors' previous studies have demonstrated that simvastatin treatment promotes neuronal survival and reduces inflammatory cytokine release from astrocytes after traumatic brain injury (TBI) in rats. Since reactive astrocytes produce inflammation mediators, in the current study the authors investigated the effect of simvastatin on astrocyte activation after TBI and its underlying signaling mechanisms. METHODS Saline or simvastatin (1 mg/kg) was orally administered to rats starting at Day 1 after TBI and then daily for 14 days. Rats were killed at 1, 3, 7, and 14 days after treatment. Brain sections and tissues were prepared for immunohistochemical staining and Western blot analysis, respectively. Cultured astrocytes were subjected to oxygen-glucose deprivation (OGD) and followed by immunocytochemical staining with glial fibrillary acidic protein/caveolin-1 and Western blot analysis. Lipid rafts were isolated from the cell lysate and Western blotting was carried out to detect the changes in epidermal growth factor receptor (EGFR) expression and phosphorylation in the lipid rafts. RESULTS Simvastatin significantly promoted neuronal survival after TBI and attenuated activation of astrocytes. Simvastatin modified the caveolin-1 expression in lipid rafts in astrocyte cell membrane, suppressed the phosphorylation of EGFR in lipid rafts of astrocytes after OGD, and inhibited the OGD-induced interleukin-1 production. CONCLUSIONS These data suggest that simvastatin reduces reactive astrogliosis and rescues neuronal cells after TBI. These beneficial effects of simvastatin may be mediated by inhibiting astrocyte activation after TBI through modifying the caveolin-1 expression in lipid rafts and the subsequent modulation of EGFR phosphorylation in lipid rafts.

Traumatic brain injury (TBI) elicits a strong inflammatory response that contributes to the acute pathological processes seen following TBI, including cerebral edema and disruption of the blood-brain barrier (BBB), in addition to longer-term neurological damage and cognitive impairment. Proteasome inhibitors reduce vascular thrombotic and inflammatory events and consequently protect vascular function. In the present study we evaluated the neuroprotective effect of Velcade (bortezomib), a potent and selective inhibitor of proteasomes, which is in clinical use for the treatment of multiple myeloma. When administered within 2 h after TBI onset, Velcade reduced inflammatory responses, lesion volume, and neurological functional deficits, and enhanced neuronal survival. Western blot and ELISA showed that Velcade decreased the expression of NF-κB. These results suggest that in the experimental setting, Velcade is an effective neuroprotective agent for the treatment of TBI.

The catalytic and regulatory subunits of class I phosphoinositide 3-kinase (PI3K) have oncogenic potential. The catalytic subunit p110 α and the regulatory subunit p85 undergo cancer-specific gain-of-function mutations that lead to enhanced enzymatic activity, ability to signal constitutively and oncogenicity. The β , γ and δ isoforms of p110 are cell-transforming as overexpressed wild-type proteins. Class I PI3Ks have the unique ability to generate phosphoinositide 3,4,5 trisphosphate (PIP 3 ). Class II and class III PI3Ks lack this ability. Genetic and cell biological evidence suggests that PIP 3 is essential for PI3K-mediated oncogenicity, explaining why class II and class III enzymes have not been linked to cancer. Mutational analysis reveals the existence of at least two distinct molecular mechanisms for the gain of function seen with cancer-specific mutations in p110 α , one causing independence from upstream receptor tyrosine kinases, the other inducing independence from Ras. An essential component of the oncogenic signal that is initiated by PI3K is the TOR (target of rapamycin) kinase. TOR is an integrator of growth and of metabolic inputs. In complex with the raptor protein (TORC1), it controls cap-dependent translation, and this function is essential for PI3K-initiated oncogenesis.