Nuclear factor-kappaB activation: from bench to bedside

NF-κB p65 subunit DNA-binding activity: association with depleted antioxidant levels in breast carcinoma patients

NF-κB is recognized as a redox-sensitive transcription factor and has been implicated in cellular response to oxidative stress. The study was designed to correlate the changes in antioxidant status with the levels of nuclear factor-κB (NF-κB) p65 subunit DNA-binding activity in relation to lymph node involvement, tumor size, and staging in breast carcinoma patients. Case control study comprised of 40 breast carcinoma patients along with 40 age- and sex-matched healthy subjects as controls. Levels of enzymatic/nonenzymatic antioxidants along with the trace elements were measured to study the antioxidant status in the study subjects. Levels of NF-κB p65 subunit DNA-binding activity was estimated by ELISA assay. The levels of enzymatic, nonenzymatic antioxidants, and trace elements were found to be significantly depleted in breast carcinoma patients in comparison to healthy controls suggesting significantly decreased levels of antioxidant activity in the breast carcinoma patients. Also, these results indicate that antioxidant levels decrease progressively with the advancement of stage and subsequent progression of disease. DNA-binding activity of NF-κB p65 subunit was higher in breast cancer patients in comparison to normal healthy controls, and the activity was found to increase with the advancement of disease. Significant correlation was observed between the DNA-binding activity of NF-κB p65 subunit and antioxidant status in the patients. The logistic regression analysis revealed decreased levels of antioxidants and increased level of DNA-binding activity of NF-κB p65 subunit were significantly associated with incidence of breast carcinoma. Depleted antioxidant status and increased level of DNA-binding activity of NF-κB p65 subunit thus point clearly of an association in relation to disease progression, clinical stage, and cytological grade in the pathophysiology of breast carcinoma.

Reciprocal effects of Toll-like receptors and miRNAs on biological processes in human health and disease: a systematic review

The roles of miRNAs in human diseases are emerging. Manipulation of miRNA expression seems to be an effective approach to control disease severity. It has recently been found that Toll-like receptors and miRNAs work by exerting reciprocal effects. Toll-like receptor stimulation can lead to up-/down-regulation of various miRNA expressions. Lipopolysaccharide induction may result in interactions between different miRNAs. Several miRNAs are involved in cancers, indicating the importance of identifying strategies to properly manipulate their expression level. The control of various miRNA expression levels, taking into consideration the plethora of their target genes and the possibility that this may lead to contracting function, which is an important issue in treatment of any miRNA-based (phenotype) disease.

A facile stereoselective total synthesis of (R)-rugulactone

An efficient and novel synthesis of (R)-rugulactone has been achieved employing Sharpless asymmetric epoxidation of allyl alcohols followed by selective hydride reduction of epoxy alcohols and olefin cross metathesis reactions.

Cancer chemoprevention by traditional chinese herbal medicine and dietary phytochemicals: targeting nrf2-mediated oxidative stress/anti-inflammatory responses, epigenetics, and cancer stem cells

Excessive oxidative stress induced by reactive oxygen species (ROS), reactive nitrogen species (RNS), and reactive metabolites of carcinogens alters cellular homeostasis, leading to genetic/epigenetic changes, genomic instability, neoplastic transformation, and cancer initiation/progression. As a protective mechanism against oxidative stress, antioxidant/detoxifying enzymes reduce these reactive species and protect normal cells from endo-/exogenous oxidative damage. The transcription factor nuclear factor-erythroid 2 p45 (NF-E2)-related factor 2 (Nrf2), a master regulator of the antioxidative stress response, plays a critical role in the expression of many cytoprotective enzymes, including NAD(P)H:quinine oxidoreductase (NQO1), heme oxygenase-1 (HO-1), UDP-glucuronosyltransferase (UGT), and glutathione S-transferase (GST). Recent studies demonstrated that many dietary phytochemicals derived from various vegetables, fruits, spices, and herbal medicines induce Nrf2-mediated antioxidant/detoxifying enzymes, restore aberrant epigenetic alterations, and eliminate cancer stem cells (CSCs). The Nrf2-mediated antioxidant response prevents many age-related diseases, including cancer. Owing to their fundamental contribution to carcinogenesis, epigenetic modifications and CSCs are novel targets of dietary phytochemicals and traditional Chinese herbal medicine (TCHM). In this review, we summarize cancer chemoprevention by dietary phytochemicals, including TCHM, which have great potential as a safer and more effective strategy for preventing cancer.

Antioxidants and human diseases

Oxidative stress plays a pivotal role in the development of human diseases. Reactive oxygen species (ROS) that includes hydrogen peroxide, hyphochlorus acid, superoxide anion, singlet oxygen, lipid peroxides, hypochlorite and hydroxyl radical are involved in growth, differentiation, progression and death of the cell. They can react with membrane lipids, nucleic acids, proteins, enzymes and other small molecules. Low concentrations of ROS has an indispensable role in intracellular signalling and defence against pathogens, while, higher amounts of ROS play a role in number of human diseases, including arthritis, cancer, diabetes, atherosclerosis, ischemia, failures in immunity and endocrine functions. Antioxidants presumably act as safeguard against the accumulation of ROS and their elimination from the system. The aim of this review is to highlight advances in understanding of the ROS and also to summarize the detailed impact and involvement of antioxidants in selected human diseases.

Activation of nuclear factor κB pathway and downstream targets survivin and livin by SHARPIN contributes to the progression and metastasis of prostate cancer

BACKGROUND

Nuclear factor κB (NFκB) signaling is strongly associated with tumor progression, and studies have shown that SHANK-associated RH domain interacting protein (SHARPIN) is crucial for NFκB pathway activation. However, the expression and functions of SHARPIN in prostate cancer (PCa) have not yet been defined.

METHODS

The expression of SHARPIN in PCa cell lines and tissues was evaluated with western blotting, quantitative real-time polymerase chain reaction, and immunohistochemistry. After SHARPIN was silenced in the PCa cell lines, western blots were used to confirm that SHARPIN physically associated with components of the NFκB pathway and the downstream targets (survivin and livin). The functions of SHARPIN in cell proliferation, migration, and invasion in vitro were measured with 5-(3-carboxymethoxyphenyl)-2-(4,5-dimenthylthiazoly)-3-(4-sulfophenyl)tetrazolium, inner salt (MTS), Transwell, and invasion assays, respectively. Flow cytometry was employed to evaluate cell apoptosis. Furthermore, tumorigenesis in vivo was examined with tumorigenicity assays.

RESULTS

SHARPIN expression was upregulated in PCa cell lines and tissues. The knockdown of SHARPIN or incubation with Bay 11-7082 (an NFκB inhibitor) led to dramatically decreased levels of phosphorylated IκBα and phosphorylated p65 in comparison with the control group. Downregulation of survivin and livin due to SHARPIN inhibition was attributable to transcriptional repression (P < .05). Decreases in cell viability, migration, invasion, and survival with a higher sensitivity to docetaxel in vitro and with repressed tumorigenesis in vivo were observed upon SHARPIN silencing, and this was consistent with the results from inhibition of the NFκB pathway and its downstream targets.

CONCLUSION

The current study demonstrates that overexpression of SHARPIN promotes activation of the NFκB pathway and downstream targets survivin and livin, which potentially contributes to PCa development.

Crebanine, an aporphine alkaloid, sensitizes TNF-α-induced apoptosis and suppressed invasion of human lung adenocarcinoma cells A549 by blocking NF-κB-regulated gene products

Crebanine is an alkaloid known to exhibit anticancer, but its mechanism is not well understood. Besides, the nuclear factor-kappa B (NF-κB) transcription factor has been correlated with inflammation, carcinogenesis, tumor cell survival, invasion, and angiogenesis. In this study, we investigated the effects of crebanine on tumor necrosis factor alpha (TNF-α)-induced NF-κB activation and the expression of NF-κB-regulated gene products. We found that crebanine reduced the cell proliferation of lung, ovarian, and breast cancer cells. Crebanine also potentiated TNF-α-induced apoptosis which correlated with the suppression of the gene products linked to cell survival, B cell lymphoma-extra large, and proliferation, cyclin D1. In addition, crebanine affected TNF-α-induced activation of caspase-8, caspase-3, and poly(ADP-ribose) polymerase cleavage, indicating that the apoptotic effects of TNF-α were enhanced by crebanine. Moreover, crebanine reduced TNF-α-induced A549 cell invasion and migration. Furthermore, crebanine suppressed the TNF-α-mediated expression of proteins that involved cancer cell invasion (matrix metalloproteinase 9 urokinase-type plasminogen activator, urokinase-type plasminogen activator receptor and intercellular adhesion molecule 1) and angiogenesis (COX-2 and VEGF), all of which are known to be regulated by NF-κB. We also demonstrated that TNF-α induced NF-κB DNA-binding activity, which was inhibited by crebanine. Moreover, crebanine suppressed the TNF-α-induced degradation of inhibitor of NF-κB alpha (IκBa), which led to reduced NF-κB translocation to the nucleus. Taken together, our results demonstrated that crebanine reduced TNF-α-induced cancer cell proliferation, invasion, and survival by suppressing NF-κB activity and expression profile of its downstream genes.

Montelukast rescues primary neurons against Aβ1-42-induced toxicity through inhibiting CysLT1R-mediated NF-κB signaling

Amyloid-β peptide (Aβ), which can invoke a cascade of inflammatory responses, is considered to play a causal role in the development and progress of Alzheimer's disease (AD). Montelukast, known as a cysteinyl leukotriene receptor 1 (CysLT1R) antagonist, is currently used for treatment of inflammatory diseases such as asthma. We have previously reported that CysLT1R activation is involved in Aβ generation. In this study, we investigated rescuing effect of CysLT1R antagonist montelukast on Aβ1-42-induced neurotoxicity in primary neurons. Our data showed that Aβ1-42 elicited a marked increase of CysLT1R expression in primary mouse neurons. This increment of CysLT1R expression was accompanied by increases of inflammatory factors such as NF-κB p65, tumor necrosis factor-α (TNFα) and interleukin-1β (IL-1β) as well as pro-apoptotic protein Caspase-3 activation and anti-apoptosis protein Bcl-2 reduction. Aβ1-42-mediated increase of CysLT1R expression was associated with Aβ1-42-induced cytotoxicity as measured by MTT reduction assay and lactate dehydrogenase (LDH) release assay. This observation was confirmed with treatment of montelukast, a selective CysLT1R antagonist, which had significant effect on Aβ1-42-induced cytotoxicity. Moreover, blockade of CysLT1R with montelukast reversed Aβ1-42-mediated increase of CysLT1R expression, and concomitant changes of the pro-inflammatory factors and the apoptosis-related proteins. The results demonstrate that montelukast rescued neurons against Aβ1-42-induced neurotoxicity, neuroinflammation and apoptosis by down-regulating CysLT1R-mediated NF-κB signaling, suggesting that CysLT1R may be a potential target for AD, and its antagonist may have beneficial effects for treatment of AD.

Loss of p53 enhances NF-κB-dependent lamellipodia formation

Tumor suppressor p53 prevents tumorigenesis and tumor growth by suppressing the activation of several transcription factors, including nuclear factor-κB (NF-κB) and STAT3. On the other hand, p53 stimulates actin cytoskeleton remodeling and integrin-related signaling cascades. Here, we examined the p53-mediated link between regulation of the actin cytoskeleton and activation of NF-κB and STAT3 in MCF-7 cells and mouse embryonic fibroblasts (MEFs). In the absence of p53, STAT3 was constitutively activated. This activation was attenuated by depleting the expression of p65, a component of NF-κB. Integrin β3 expression and lamellipodia formation were also downregulated by NF-κB depletion. Inhibition of integrin αvβ3, Rac1 or Arp2/3, which diminished lamellipodia formation, suppressed STAT3 activation induced by p53 depletion. These results suggest that loss of p53 leads to STAT3 activation via NF-κB-dependent lamellipodia formation. Our study proposes a novel role for p53 in modulating the actin cytoskeleton through suppression of NF-κB, which restricts STAT3 activation.

Protective effect of pranlukast on Aβ₁₋₄₂-induced cognitive deficits associated with downregulation of cysteinyl leukotriene receptor 1

Deposition of extracellular amyloid-β (Aβ) peptide is one of the pathological hallmarks of Alzheimer's disease (AD). Accumulation of Aβ is thought to associate with cognition deficits, neuroinflammation and apoptosis observed in AD. However, effective neuroprotective approaches against Aβ neurotoxicity are unavailable. In the present study, we analysed the effects of pranlukast, a selective cysteinyl leukotriene receptor 1 (CysLT₁R) antagonist, on the impairment of learning and memory formation induced by Aβ and the probable underlying electrophysiological and molecular mechanisms. We found that bilateral intrahippocampal injection of Aβ₁₋₄₂ resulted in a significant decline of spatial learning and memory of mice in the Morris water maze (MWM) and Y-maze tests, together with a serious depression of in vivo hippocampal long-term potentiation (LTP) in the CA1 region of the mice. Importantly, this treatment caused significant increases in CysLT₁R expression and subsequent NF-κB signaling, caspase-3 activation and Bcl-2 downregulation in the hippocampus or prefrontal cortex. Oral administration of pranlukast at 0.4 or 0.8 mg/kg for 4 wk significantly reversed Aβ₁₋₄₂-induced impairments of cognitive function and hippocampal LTP in mice. Furthermore, pranlukast reversed Aβ₁₋₄₂-induced CysLT₁R upregulation, and markedly suppressed the Aβ₁₋₄₂-triggered NF-κB pathway, caspase-3 activation and Bcl-2 downregulation in the hippocampus and prefrontal cortex in mice. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay confirmed its presence in the brain after oral administration of pranlukast in mice. These data disclose novel findings about the therapeutic potential of pranlukast, revealing a previously unknown therapeutic possibility to treat memory deficits associated with AD.

Capsaicin inhibits cell proliferation by cytochrome c release in gastric cancer cells

Capsaicin (trans-8-methyl-N-vanillyl-6-nonenamide) is the principal pungent component in hot peppers. The role of capsaicin in carcinogenesis is quite controversial. Although some investigators suspect that capsaicin is a carcinogen, co-carcinogen, or tumor promoter, others have reported that it has chemopreventive and chemotherapeutic effects. The present study aimed to evaluate the cytotoxicity and chemosensitizing activities of capsaicin alone and on 5-flourouracil (5-FU)-treated gastric cancer cells. In this study, the gastric cancer cell line HGC-27 was used and capsaicin used as a chemosensitizer and 5-flourouracil (5-FU) was used as chemotherapeutic. Cytotoxicity and chemosensitizing activities were analyzed with MTT assay; supernatant levels of LDH and glucose were detected as biochemical markers of cell viability; cytochrome c and AIF were evaluated with western blot; and additionally, wound-healing assays were employed. Results suggested that capsaicin had significant anticancer abilities; such capsaicin were capable of causing multifold decreases in the half maximal inhibitory concentration IC50 value of 5-FU. The continuing controversy surrounding consumption or topical application of capsaicin clearly suggests that more well-controlled epidemiologic studies are needed to evaluate the safety and efficacy of capsaicin use. In summary, the present study demonstrated that capsaicin has the potential to be used for treating gastric carcinoma with 5-FU in vitro.

Long non-coding RNAs: new players in ocular neovascularization

Pathological neovascularization are the most prevalent causes of moderate or severe vision loss. Long non-coding RNAs (lncRNAs) have emerged as a novel class of regulatory molecules involved in numerous biological processes and complicated diseases. However, the role of lncRNAs in ocular neovascularization is still unclear. Here, we constructed a murine model of ocular neovascularization, and determined lncRNA expression profiles using microarray analysis. We identified 326 or 51 lncRNAs that were significantly either up-regulated or down-regulated in the vaso-obliteration or neovascularization phase, respectively. Based on Pearson correlation analysis, lncRNAs/mRNAs co-expression networks were constructed. GO enrichment analysis of lncRNAs-co-expressed mRNAs indicated that the biological modules were correlated with chromosome organization, extracellular region and guanylate cyclase activator activity in the vaso-obliteration phase, and correlated with cell proliferation, extracellular region and guanylate cyclase regulator activity in the neovascularization phase. KEGG pathway analysis indicated that MAPK signaling was the most significantly enriched pathway in both phases. Importantly, Vax2os1 and Vax2os2 were not only dynamically expressed in the vaso-obliteration and neovascularization phases, but also significantly altered in the aqueous humor of patients with neovascular age-related macular degeneration (AMD), suggesting a potential role of lncRNAs in the regulation of ocular neovascularization. Taken together, this study provided novel insights into the molecular pathogenesis of ocular neovascularization. The intervention of dysregulated lncRNA could become a potential target for the prevention and treatment of ocular vascular diseases.

Lysine deacetylase (KDAC) regulatory pathways: an alternative approach to selective modulation

Protein lysine deacetylases (KDACs), including the classic Zn(2+) -dependent histone deacetylases (HDACs) and the nicotinamide adenine dinucleotide (NAD(+) )-requiring sirtuins, are enzymes that play critical roles in numerous biological processes, particularly the epigenetic regulation of global gene expression programs in response to internal and external cues. Dysregulation of KDACs is characteristic of several human diseases, including chronic metabolic, neurodegenerative, and cardiovascular diseases and many cancers. This has led to the development of KDAC modulators, two of which (HDAC inhibitors vorinostat and romidepsin) have been approved for the treatment of cutaneous T cell lymphoma. By their nature, existing KDAC modulators are relatively nonspecific, leading to pan-KDAC changes and undesired side effects. Given that KDACs are regulated at many levels, including transcriptional, post-translational, subcellular localization, and through their complexation with other proteins, it should be possible to affect specific KDAC activity through manipulation of endogenous signaling pathways. In this Minireview, we discuss our present knowledge of the cellular controls of KDAC activity and examples of their pharmacologic regulation.

Potential association between TLR4 and chitinase 3-like 1 (CHI3L1/YKL-40) signaling on colonic epithelial cells in inflammatory bowel disease and colitis-associated cancer

Inflammatory bowel disease (IBD) is a group of inflammatory disorders in the small and large intestines. Several studies have proved that persistent and disregulated host/microbial interactions are required for the development of IBD. It is well known that chronic IBD is strongly associated with an increased risk of developing colorectal cancer by 0.5-1% annually, 8-10 years after the initial diagnosis. To detect the tiny dysplasia or early stage of cancer in chronic IBD patients, a tremendous amount of effort is currently directed for improving colonoscopic technology and noninvasive serological marker development. However, there is only a limited amount of data available to understand the exact mechanism of how long term chronic colitis is connected to the development of colorectal tumors. Recently, our group has identified significantly increased expression of chitinase 3-like 1 (CHI3L1) molecule in non-dysplastic mucosa from patients with IBD and remote dysplasia/cancer, compared to patients with IBD without dysplasia or healthy controls. CHI3L1 seems to contribute to the proliferation, migration, and neoplastic progression of colonic epithelial cells (CECs) under inflammatory conditions. Furthermore, the TLR4-mediated intracellular signaling cascade is likely to interact with CHI3L1 signaling in CECs. In this review article, we have concisely summarized the cellular and molecular mechanisms underlining the development of IBD and colitis-associated cancer, with particular focus on the TLR4- and CHI3L1-signaling pathways in CECs.

Investigation of NF-κB1 and NF-κBIA gene polymorphism in non-small cell lung cancer

Lung cancer is a complex, multifactorial disease which is the leading cause of cancer death in both men and women. NF-κB is a transcription factor which is known to affect the expression of more than 150 genes related to inflammation, lymphocyte activation, cell proliferation, differentiation, and apoptosis, as well as contributing to cell apoptosis and survival. However, NF-κBIA (IκBα) is the inhibitor of the transcription factor. The -94ins/delATTG polymorphism of the NF-κB1 gene promoter region which causes a functional effect and NF-κBIA 3′UTR A → G polymorphism has been shown to be related to various inflammatory diseases and cancer. Ninety-five NSCLC patients and 99 healthy controls were included in study. The NF-κB1 -94ins/delATTG and NF-κBIA 3′UTR A → G polymorphism have been studied by using PCR-RFLP method. It was found that the NF-κB1 -94ins/delATTG DD genotype and D allele frequencies were higher in patients than healthy controls and the presence of the DD genotype has a 3.5-fold increased risk of the disease (P: 0.014). This study is the first to investigate the NF-κB1 -94ins/delATTG and NF-κBIA 3′UTR A → G polymorphism together in the Turkish population. According to the results, the NF-κB1 -94ins/del ATTG promoter polymorphism may have a role in lung carcinogenesis and prognosis.

Regulation of Mcl-1 by constitutive activation of NF-κB contributes to cell viability in human esophageal squamous cell carcinoma cells

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is one of the most lethal malignancies with a 5-year survival rate less than 15%. Understanding of the molecular mechanisms involved in the pathogenesis of ESCC becomes critical to develop more effective treatments.

METHODS

Mcl-1 expression was measured by reverse transcription (RT)-PCR and Western blotting. Human Mcl-1 promoter activity was evaluated by reporter gene assay. The interactions between DNA and transcription factors were confirmed by electrophoretic mobility shift assay (EMSA) in vitro and by chromatin immunoprecipitation (ChIP) assay in cells.

RESULTS

Four human ESCC cell lines, TE-1, Eca109, KYSE150 and KYSE510, are revealed increased levels of Mcl-1 mRNA and protein compare with HaCaT, an immortal non-tumorigenic cell line. Results of reporter gene assays demonstrate that human Mcl-1 promoter activity is decreased by mutation of kappaB binding site, specific NF-kappaB inhibitor Bay11-7082 or dominant inhibitory molecule DNMIkappaBalpha in TE-1 and KYSE150 cell lines. Mcl-1 protein level is also attenuated by Bay11-7082 treatment or co-transfection of DNMIkappaBalpha in TE-1 and KYSE150 cells. EMSA results indicate that NF-kappaB subunits p50 and p65 bind to human Mcl-1-kappaB probe in vitro. ChIP assay further confirm p50 and p65 directly bind to human Mcl-1 promoter in intact cells, by which regulates Mcl-1 expression and contributes to the viability of TE-1 cells.

CONCLUSIONS

Our data provided evidence that one of the mechanisms of Mcl-1 expression in human ESCC is regulated by the activation of NF-kappaB signaling. The newly identified mechanism might provide a scientific basis for developing effective approaches to treatment human ESCC.

Induction of apoptosis through oxidative stress-related pathways in MCF-7, human breast cancer cells, by ethyl acetate extract of Dillenia suffruticosa

Background

Breast cancer is one of the most dreading types of cancer among women. Herbal medicine has becoming a potential source of treatment for breast cancer. Herbal plant Dillenia suffruticosa (Griff) Martelli under the family Dilleniaceae has been traditionally used to treat cancerous growth. In this study, the anticancer effect of ethyl acetate extract of D. suffruticosa (EADs) was examined on human breast adenocarcinoma cell line MCF-7 and the molecular pathway involved was elucidated.

Methods

EADs was obtained from the root of D. suffruticosa by using sequential solvent extraction. Cytotoxicity was determined by using MTT assay, mode of cell death by cell cycle analysis and apoptosis induction by Annexin-FITC/PI assay. Morphology changes in cells were observed under inverted light microscope. Involvement of selected genes in the oxidative stress-mediated signaling pathway was explored using multiplex gene expression analysis.

Results

The treatment of EADs caused cytotoxicity to MCF-7 cells in a dose- and time-dependent manner at 24, 48 and 72 hours with IC₅₀ of 76 ± 2.3, 58 ± 0.7 and 39 ± 3.6 μg/mL, respectively. The IC₅₀ of tamoxifen-treated MCF-7 cells was 8 ± 0.5 μg/mL. Induction of apoptosis by EADs was dose- and time- dependent. EADs induced non-phase specific cell cycle arrest at different concentration and time point. The multiplex mRNA expression study indicated that EADs-induced apoptosis was accompanied by upregulation of the expression of SOD1, SOD2, NF-κB, p53, p38 MAPK, and catalase, but downregulation of Akt1.

Conclusion

It is suggested that EADs induced apoptosis in MCF-7 cells by modulating numerous genes which are involved in oxidative stress pathway. Therefore, EADs has the potential to act as an effective intervention against breast cancer cells.

Sensitization of U937 leukemia cells to doxorubicin by the MG132 proteasome inhibitor induces an increase in apoptosis by suppressing NF-kappa B and mitochondrial membrane potential loss

Background

The resistance of cancerous cells to chemotherapy remains the main limitation for cancer treatment at present. Doxorubicin (DOX) is a potent antitumor drug that activates the ubiquitin-proteasome system, but unfortunately it also activates the Nuclear factor kappa B (NF-кB) pathway leading to the promotion of tumor cell survival. MG132 is a drug that inhibits I kappa B degradation by the proteasome-avoiding activation of NF-кB. In this work, we studied the sensitizing effect of the MG132 proteasome inhibitor on the antitumor activity of DOX.

Methods

U937 human leukemia cells were treated with MG132, DOX, or both drugs. We evaluated proliferation, viability, apoptosis, caspase-3, -8, and −9 activity and cleavage, cytochrome c release, mitochondrial membrane potential, the Bcl-2 and Bcl-XL antiapoptotic proteins, senescence, p65 phosphorylation, and pro- and antiapoptotic genes.

Results

The greatest apoptosis percentage in U937 cells was obtained with a combination of MG132 + DOX. Likewise, employing both drugs, we observed a decrease in tumor cell proliferation and important caspase-3 activation, as well as mitochondrial membrane potential loss. Therefore, MG132 decreases senescence, p65 phosphorylation, and the DOX-induced Bcl-2 antiapoptotic protein. The MG132 + DOX treatment induced upregulation of proapoptotic genes BAX, DIABLO, NOXA, DR4, and FAS. It also induced downregulation of the antiapoptotic genes BCL-XL and SURVIVIN.

Conclusion

MG132 sensitizes U937 leukemia cells to DOX-induced apoptosis, increasing its anti-leukemic effectiveness.

PSY-1, a Taxus chinensis var. mairei Extract, Inhibits Cancer Cell Metastasis by Interfering with MMPs

Cancer is the most common disease worldwide, with death often occurring as a result of metastasis. Thus, interfering with metastasis has been regarded as a promising strategy to improve the current cancer treatments. However, exploration and development of novel anti-metastatic agents remains a major challenge. Recent evidence indicated that a polysaccharide isolated from Taxus yunnanensis suppressed tumor cells proliferation. With the objective of seeking bioactive extracts, we had previously isolated, purified and characterized a complex, water-soluble polysaccharides, PSY-1, from the leaves of Taxus chinensis var. mairei, and identified its anti-neoplastic effects. In this study, we focused on the effects of PSY-1 on cancer metastasis and its mechanism(s). The results illustrated that PSY-1 effectively suppressed the migration and invasion ability of the melanoma cancer cell line B16-F10, caused down-regulation of MMP-2 and MMP-9, and that the NF-κB pathway was involved in the anti-metastatic effects imposed by PSY-1.

Identification and expression profiles of genes and protens in SMMC-7721 cells

In the study presented here, we first evaluated effect of CDDP on liver cancer cells SMMC-7721 apoptosis and motility capacity. Then, we evaluate inhibitory effect of CDDP on tumour growth and its possible molecular mechanism in liver cancer mice model. Results showed that the apoptosis rate of cells decreased with increasing CDDP. Analysis of the effect of the CDDP on cell cycle was performed by flow cytometry and results show a dose-dependent increase in the percentage of cells in the S-phase of the cell cycle, with a decrease in the percentage of cells in the G1 and G2/M phases. CDDP did not close the wound even after 48 h, as opposed to untreated cells (0 mg/l). Similarly, the migratory and invasion capacity of SMMC-7721 cells was also reduced after treatment with CDDP, as evaluated by a transwell assay. Animal experiment indicated that CDDP administration could increase blood WBC, total protein, albumin and A/G, decrease blood alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase levels in hepatocellular carcinomas mice. Immunohistochemistry analysis showed that positive expression of Fas and Bax proteins in the medicine-treated (II, III) group was significantly higher, whereas the expression of NF-κB, P53, Bcl-2 proteins was significantly lower than those of the control group. Gene expression analysis using Real time PCR methods revealed a significant up-regulation in the expression levels of Bax mRNA in the medicne-treated (II, III) group when compared to untreated control. In contrast, CDDP-treated group showed a significant down regulation in the expression levels of Bcl-2 mRNA as compared to untreated control group. These results are in agreement with immunohistochemistry data. Our observations indicate that CDDP has damaged effects on liver tumour cells SMMC-7721 including apoptosis, motility and cell cycle under in vitro. CDDP can enhance pro-apoptosis gene Fas, Bax expression, decrease anti-apoptosis genes Bcl-2 expression, and mutant genes P53, NF-κB proteins expression.

Selective killing of lung cancer cells by miRNA-506 molecule through inhibiting NF-κB p65 to evoke reactive oxygen species generation and p53 activation

The tumor suppressor p53, nuclear factor-κB (NF-κB) and reactive oxygen species (ROS) have crucial roles in tumorigenesis, although the mechanisms of cross talk between these factors remain largely unknown. Here we report that miR-506 upregulation occurs in 83% of lung cancer patients (156 cases), and its expression highly correlates with ROS. Ectopic expression of miR-506 inhibits NF-κB p65 expression, induces ROS accumulation and then activates p53 to suppress lung cancer cell viability, but not in normal cells. Interestingly, p53 promotes miR-506 expression level, indicating that miR-506 mediates cross talk between p53, NF-κB p65 and ROS. Furthermore, we demonstrated that miR-506 mimics inhibited tumorigenesis in vivo, implicating that miR-506 might be a potential therapeutic molecule for selective killing of lung cancer cells.

Montelukast targeting the cysteinyl leukotriene receptor 1 ameliorates Aβ1-42-induced memory impairment and neuroinflammatory and apoptotic responses in mice

Montelukast, known as a cysteinyl leukotriene receptor 1 (CysLT1R) antagonist, is currently used for treatment of inflammatory diseases such as asthma. Here, we investigated effects of montelukast on neuroinflammatory, apoptotic responses, and memory performance following intracerebral infusions of amyloid-β (Aβ). The data demonstrated that intracerebroventrical infusions of aggregated Aβ1-42 (410 pmol/mouse) produced deficits in learning ability and memory, as evidenced by increase in escape latency during acquisition trials and decreases in exploratory activities in the probe trial in Morris water maze (MWM) task, and by decrease in the number of correct choices and increase in latency to enter the shock-free compartment in Y-maze test, and caused significant increases in pro-inflammatory cytokines such as NF-κB p65, TNF-α and IL-1β as well as pro-apoptotic molecule caspase-3 activation and anti-apoptotic protein Bcl-2 downregulation in hippocampus and cortex. Interestingly, this treatment resulted in upregulation of protein or mRNA of CysLT1R in both hippocampus and cortex. Blockade of CysLT1R by repeated treatment with montelukast (1 or 2 mg/kg, ig, 4 weeks) reduced Aβ1-42-induced CysLT1R expression and also suppressed Aβ1-42-induced increments of NF-κB p65, TNF-α, IL-1β and caspase-3 activation, and Bcl-2 downregulation in the hippocampus and cortex. Correspondingly, montelukast treatment significantly improved Aβ1-42-induced memory impairment in mice, but had little effect on normal mice. Our results show that montelukast may ameliorate Aβ1-42-induced memory impairment via inhibiting neuroinflammation and apoptosis mediated by CysLT1R signaling, suggesting that CysLT1R antagonism represents a novel treatment strategy for Alzheimer's disease.

Transmembrane protein with unknown function 16A overexpression promotes glioma formation through the nuclear factor-κB signaling pathway

Ion channels have been suggested to be important in the development and progression of tumors, however, chloride channels have rarely been analyzed in tumorigenesis. More recently, transmembrane protein with unknown function 16A (TMEM16A), hypothesized to be a candidate calcium‑activated Cl‑ channel, has been found to be overexpressed in a number of tumor types. Although several studies have implicated the overexpression of TMEM16A in certain tumor types, the exact role of TMEM16A in gliomas and the underlying mechanisms in tumorigenesis, remain poorly understood. In the present study, the role of TMEM16A in gliomas and the potential underlying mechanisms were analyzed. TMEM16A was highly abundant in various grades of gliomas and cultured glioma cells. Knockdown of TMEM16A suppressed cell proliferation, migration and invasion. Furthermore, nuclear factor‑κB (NF‑κB) was activated by overexpression of TMEM16A. In addition, TMEM16A regulated the expression of NF‑κB‑mediated genes, including cyclin D1, cyclin E and c‑myc, involved in cell proliferation, and matrix metalloproteinases (MMPs)‑2 and MMP‑9, which are associated with the migration and invasion of glioma cells. Collectively, results of the present study provide evidence for the involvement of TMEM16A in gliomas and the potential mechanism through which TMEM16A promotes glioma formation.

C5-curcuminoid-dithiocarbamate based molecular hybrids: synthesis and anti-inflammatory and anti-cancer activity evaluation

The C5-curcumin-dithiocarbamate analogues were synthesized in search of new molecules with anti-proliferation potential against cancer cells. These new compounds demonstrated higher anti-proliferation and anti-inflammatory activity against cancer cell lines in comparison to curcumin.

Molecular mechanisms behind anti-cancer effects of curcumin in hepatocellular carcinoma

Primary liver cancer, also known as hepatocellular carcinoma (HCC), is one of the most lethal cancers worldwide. Most HCC cases are reported in the developing countries in Asia and Africa. Viral hepatitis, alcoholism as well as dietary carcinogens, such as aflatoxins and nitrosoamines, contribute to HCC. Surgical resection is the best treatment for early HCC, and Chinese medicine is one of the main measures for the treatment of advanced HCC. Numerous studies show that curcumin has anti-cancer, anti-oxidant and anti-inflammatory properties. This article will discuss the mechanisms behind anti-cancer effects of curcumin in HCC.

MafK positively regulates NF-κB activity by enhancing CBP-mediated p65 acetylation

Reactive oxygen species, produced by oxidative stress, initiate and promote many metabolic diseases through activation/suppression of redox-sensitive transcription factors. NF-κB and Nrf2 are important regulators of oxidation resistance and contribute to the pathogenesis of many diseases. We identified MafK, a novel transcriptional regulator that modulates NF-κB activity. MafK knockdown reduced NF-κB activation, whereas MafK overexpression enhanced NF-κB function. MafK mediated p65 acetylation by CBP upon LPS stimulation, thereby facilitating recruitment of p65 to NF-κB promoters such as IL-8 and TNFα. Consistent with these results, MafK-depleted mice showed prolonged survival with a reduced hepatic inflammatory response after LPS and D-GalN injection. Thus, our findings reveal a novel mechanism by which MafK controls NF-κB activity via CBP-mediated p65 acetylation.

Oral free and dipeptide forms of glutamine supplementation attenuate oxidative stress and inflammation induced by endotoxemia

OBJECTIVE

The aim of the present study was to determine the effects of oral supplementation with L-glutamine plus L-alanine (GLN+ALA), both in the free form and L-alanyl-L-glutamine dipeptide (DIP) in endotoxemic mice.

METHODS

B6.129 F2/J mice were subjected to endotoxemia (Escherichia coli lipopolysaccharide [LPS], 5 mg/kg, LPS group) and orally supplemented for 48 h with either L-glutamine (1 g/kg) plus L-alanine (0.61 g/kg) (GLN+ALA-LPS group) or 1.49 g/kg DIP (DIP-LPS group). Plasma glutamine, cytokines, and lymphocyte proliferation were measured. Liver and skeletal muscle glutamine, glutathione (GSH), oxidized GSH (GSSG), tissue lipoperoxidation (TBARS), and nuclear factor (NF)-κB-interleukin-1 receptor-associated kinase 1 (IRAK1)-Myeloid differentiation primary response gene 88 pathway also were determined.

RESULTS

Endotoxemia depleted plasma (by 71%), muscle (by 44%), and liver (by 49%) glutamine concentrations (relative to the control group), which were restored in both GLN+ALA-LPS and DIP-LPS groups (P < 0.05). Supplemented groups reestablished GSH content, intracellular redox status (GSSG/GSH ratio), and TBARS concentration in muscle and liver (P < 0.05). T- and B-lymphocyte proliferation increased in supplemented groups compared with controls and LPS group (P < 0.05). Tumor necrosis factor-α, interleukin (IL)-6, IL-1 β, and IL-10 increased in LPS group but were attenuated by the supplements (P < 0.05). Endotoxemic mice exhibited higher muscle gene expression of components of the NF-κB pathway, with the phosphorylation of IκB kinase-α/β. These returned to basal levels (relative to the control group) in both GLN+ALA-LPS and DIP-LPS groups (P < 0.05). Higher mRNA of IRAK1 and MyD88 were observed in muscle of LPS group compared with the control and supplemented groups (P < 0.05).

CONCLUSION

Oral supplementations with GLN+ALA or DIP are effective in attenuating oxidative stress and the proinflammatory responses induced by endotoxemia in mice.

Anti-invasion effect of crebanine and O-methylbulbocapnine from Stephania venosa via down-regulated matrix metalloproteinases and urokinase plasminogen activator

The alkaloids isolated from Stephania venosa (S. venosa) have been shown to inhibit the proliferation and to induce the apoptosis of cancer cells. However, the anti-metastatic effect of the alkaloids on cancer cell invasion is unknown. In this study, we investigated the anti-invasive properties of four alkaloids from S. venosa, crebanine (CN), O-methylbulbocapnine (OMBC), tetrahydropalmatine (THP), and N-methyltetrahydropalmatine (NMTHP), in HT1080 human fibrosacroma cells. Treatment of the cells with 15 µg/mL of CN and OMBC reduced the chemo-invasion of HT1080 cells to 45 and 50%, respectively, whereas THP and NMTHP had a negative effect. On the other hand, CN and OMBC had no effect on cell migration. Matrix metalloproteinases (MMPs) and urokinase plasminogen activator (uPA) are the extracellular matrix (ECM) degradation enzymes that play an important role in cancer cell metastasis. Results from zymography and western blot analysis showed that CN and OMBC comparatively reduced MMP-2, MMP-9, MT1-MMP and uPA expression in a dose-dependent manner. However, CN and OMBC had no effect on the activity of collagenase, MMP-2 and MMP-9. We also found that CN and OMBC reduced the nuclear translocation and DNA binding activity of nuclear factor kappa B (NF-κB), which is the expressed mediator of ECM degradation enzymes. These findings demonstrated that CN and OMBC mediated HT1080 cell invasion by the reduction of MMP-2, MMP-9, uPA and MT1-MMP expression, possibly by targeting of NF-κB signaling pathway in the HT1080 cells.

Pulmonary oxidative stress, inflammation and cancer: respirable particulate matter, fibrous dusts and ozone as major causes of lung carcinogenesis through reactive oxygen species mechanisms

Reactive oxygen or nitrogen species (ROS, RNS) and oxidative stress in the respiratory system increase the production of mediators of pulmonary inflammation and initiate or promote mechanisms of carcinogenesis. The lungs are exposed daily to oxidants generated either endogenously or exogenously (air pollutants, cigarette smoke, etc.). Cells in aerobic organisms are protected against oxidative damage by enzymatic and non-enzymatic antioxidant systems. Recent epidemiologic investigations have shown associations between increased incidence of respiratory diseases and lung cancer from exposure to low levels of various forms of respirable fibers and particulate matter (PM), at occupational or urban air polluting environments. Lung cancer increases substantially for tobacco smokers due to the synergistic effects in the generation of ROS, leading to oxidative stress and inflammation with high DNA damage potential. Physical and chemical characteristics of particles (size, transition metal content, speciation, stable free radicals, etc.) play an important role in oxidative stress. In turn, oxidative stress initiates the synthesis of mediators of pulmonary inflammation in lung epithelial cells and initiation of carcinogenic mechanisms. Inhalable quartz, metal powders, mineral asbestos fibers, ozone, soot from gasoline and diesel engines, tobacco smoke and PM from ambient air pollution (PM₁₀ and PM₂.₅) are involved in various oxidative stress mechanisms. Pulmonary cancer initiation and promotion has been linked to a series of biochemical pathways of oxidative stress, DNA oxidative damage, macrophage stimulation, telomere shortening, modulation of gene expression and activation of transcription factors with important role in carcinogenesis. In this review we are presenting the role of ROS and oxidative stress in the production of mediators of pulmonary inflammation and mechanisms of carcinogenesis.

Suppression of inflammatory cascade is implicated in methyl amooranin-mediated inhibition of experimental mammary carcinogenesis

Breast cancer represents the second leading cause of cancer-related deaths among women worldwide and preventive therapy could reverse or delay the devastating impact of this disease. Methyl-amooranin (methyl-25-hydroxy-3-oxoolean-12-en-28-oate, AMR-Me), a novel synthetic oleanane triterpenoid, reduced the incidence and burden of 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumors in rats through antiproliferative and proapoptotic effects. Since chronic inflammation plays an important role in the pathogenesis of breast cancer and several synthetic oleanane compounds are known potent anti-inflammatory agents, we aim to investigate anti-inflammatory mechanisms of AMR-Me by monitoring various proinflammatory and stress markers, such as cyclooxygenase-2 (COX-2) and heat shock protein 90 (HSP90), and nuclear factor-κB (NF-κB) signaling during DMBA mammary tumorigenesis in rats. Mammary tumors were harvested from a chemopreventive study in which AMR-Me (0.8-1.6 mg/kg) was found to inhibit mammary carcinogenesis in a dose-response manner. The expressions of COX-2, HSP90, NF-κB, and inhibitory κB-α (IκB-α) were determined by immunohistochemistry and reverse transcription-polymerase chain reaction. AMR-Me downregulated the expression of intratumor COX-2 and HSP90, suppressed the degradation of IκB-α, and reduced the translocation of NF-κB from cytosol to nucleus. Our present study provides the first in vivo evidence that NF-κB-evoked inflammatory cascade is a major target of AMR-Me in breast cancer. Our current results together with our previous findings suggest that disruption of NF-κB signaling contributes to anti-inflammatory, antiproliferative, and apoptosis-inducing mechanisms involved in AMR-Me-mediated chemoprevention of rat mammary carcinogenesis. These encouraging mechanistic results coupled with a safety profile should facilitate the clinical development of AMR-Me as breast cancer chemopreventive drug.

Modulation of the expression of the proinflammatory IL-8 gene in cystic fibrosis cells by extracts deriving from olive mill waste water

A persistent recruitment of neutrophils in the bronchi of cystic fibrosis (CF) patients contributes to aggravate the airway tissue damage, suggesting the importance of modulating the expression of chemokines, including IL-8 during the management of the CF patients. Polyphenols rich extracts derived from waste water from olive mill, obtained by a molecular imprinting approach, have been investigated in order to discover compounds able to reduce IL-8 expression in human bronchial epithelial cells (IB3-1 cells), derived from a CF patient with a ΔF508/W1282X mutant genotype and stimulated with TNF-alpha. Initially, electrophoretic mobility shift assays (EMSAs) were performed to determine whether the different active principles were able to inhibit the binding between transcription factor (TF) NF-kappaB and DNA consensus sequences. Among different representative active principles present in the extract, three compounds were selected, apigenin, oleuropein, and cyanidin chloride, which displayed remarkable activity in inhibiting NF-kappaB/DNA complexes. Utilizing TNF-alpha-treated IB3-1 cells as experimental model system, we demonstrated that apigenin and cyanidin chloride are able to modulate the expression of the NF-kappaB-regulated IL-8 gene, while oleuropein showed no effect in regulating the expression of the gene IL-8.

The involvement of SIRT1 and transcription factor NF-κB (p50/p65) in regulation of porcine ovarian cell function

The role of either mTOR system/enzyme sirtuin1 (SIRT1) or transcription factor NF-κB in the direct control of ovarian function has not been estabished. The aim of our in vitro experiments was to examine the involvement of SIRT1 and the p65 and p50 subunits of NFκB in control of porcine ovarian granulosa cell functions and the interrelationships between SIRT1, NFκB (p65, p50) 30 and FSH in the ovary. Monolayers of primary granulosa cells were transfected with gene constructs encoding either SIRT1 or p65 and p50, and thereafter cultured with, or without, addition of FSH. The accumulation of markers of proliferation (cyclin B1 and cyclin-dependent protein kinase Cdc2/p34) and proteins p50, p65 and SIRT1 in the cells was detected by using SDS-PAGE/Western immunoblotting and immunocytochemistry. The secretion of progesterone (P4) and insulin-like growth factor I (IGF-I) was measured by using radioimmunoassay. It was observed that transfection of cells with a SIRT1 gene construct promoted accumulation of proliferation markers, Cdc2/p34, cyclin B1, decreased accumulation of p50 and p65 and stimulated release of P4 and IGF-I. Co-transfection of cells with cDNA p50 and cDNA p65 enhanced the accumulation of SIRT1 and the release of P4 but did not influence the release of IGF-I. Adding FSH to the culture medium stimulated accumulation of both subunits of NF-κB, as well as accumulation of Cdc2/p34, cyclin B1 and release of both P4 and IGF-I. The ability of FSH to promote NF-κB accumulation, the similarity of the main effects of FSH, SIRT1 and NF-κB, as well as the inability of NF-κB to substantially modify the the majority of FSH effects suggest that SIRT1/NF-κB system could be a mediator of FSH action on ovarian cell functions. On the other hand, SIRT1 was able to inhibit NF-κB and to change stimulatory the effect of FSH on NF-κB from stimulatory to inhibitory. This could suggest the existence of negative feedback control of FSH/NF-κB system by high amounts of SIRT1. Our observations (1) confirm the previous data on proliferation, P4 and IGF-I release in ovarian cells and their up-regulation by FSH, (2) demonstrate the presence of SIRT1, NF-κB/p50 and NF-κB/p65 in these cells, (3) show for the first time the involvement of SIRT1 and NF-κB in direct control of proliferation and secretory activity of ovarian cells, (4) represent the first data on interrelationships between FSH, SIRT1 and NF-κB within the ovary.

Role of nuclear factor-κB in female breast cancer: a study in Indian patients

INTRODUCTION

The nuclear factor κB (NF-κB) is a super family of transcription factors which plays important roles in development and progression of cancer. The present investigation concerns NF-κB /p65 activity in human breast cancers with overexpression of ER, PR, HER-2/neu, as well as the significance of p65 expression with regard to menopausal status, stage, grade, tumor size, nodal status, and NPI of invasive ductal carcinomas in Eastern India.

MATERIALS AND METHODS

In this hospital based study 57 breast cancer patients attending a Breast Clinic of a reputed institute of Eastern India were assessed for p65 protein expression in breast tumor tissue samples by Western blotting. ER, PR and HER-2/neu expression was determined by immunohistochemistry.

RESULTS

NF-κB/p65 was significantly associated with advanced stage, large tumor size (≥5 cm), high grade, negative ER, negative PR, and positive HER-2/neu. High NF-κB/p65 expression was more frequent in patients with a high NPI (NPI≥5.4, 84.6%) compared with low NPI (<5.4, 44.4%) and this association was statistically significant (p=0.002).

CONCLUSION

NF-κB/p65 overexpression was associated with advanced stage, large tumor size, high grade, and high NPI which are poor prognostic factors linked to enhanced aggressiveness of the disease. NF-κB/p65 expression implies aggressive biological behavior of breast cancer and this study validates significant association of NF-κB /p65 overexpression with negative estrogen and progesterone receptor status and overexpression of HER-2/neu oncoprotein. In our good clinical practice, patients with NF-κB positive tumors need to be treated aggressively.

Deubiquitinase inhibition of 19S regulatory particles by 4-arylidene curcumin analog AC17 causes NF-κB inhibition and p53 reactivation in human lung cancer cells

Proteasome inhibitors have been suggested as potential anticancer agents in many clinical trials. Recent evidence indicates that proteasomal deubiquitinase (DUB) inhibitors, bearing a different mechanism from that of traditional proteasome inhibitors, would be appropriate candidates for new anticancer drug development. In the present study, we describe the deubiquitinase inhibition of 19S regulatory particles (19S RP) by AC17, a 4-arylidene curcumin analog synthesized in our laboratory. Although 4-arylidene curcumin analogs were reported to act as inhibitory κB (IκB) kinase (IKK) inhibitors, AC17 instead induced a rapid and marked accumulation of ubiquitinated proteins without inhibiting proteasome proteolytic activities. In contrast to its parent compound, curcumin, which is a proteasome proteolytic inhibitor, AC17 serves as an irreversible deubiquitinase inhibitor of 19S RP, resulting in inhibition of NF-κB pathway and reactivation of proapoptotic protein p53. In addition, in a murine xenograft model of human lung cancer A549, treatment with AC17 suppresses tumor growth in a manner associated with proteasome inhibition, NF-κB blockage, and p53 reactivation. These results suggest that 4-arylidene curcumin analogs are novel 19S deubiquitinase inhibitors with great potential for anticancer drug development.

Rho kinase inhibitor fasudil protects against β-amyloid-induced hippocampal neurodegeneration in rats

BACKGROUND AND PURPOSE

Alzheimer's disease (AD) is a progressive neurodegenerative disorder, and Aβ-induced neuronal damage is the major pathology of AD. There is increasing evidence that neuroinflammation induced by Aβ is also involved in the pathogenesis of AD. Fasudil is a Rho kinase inhibitor and has been reported to have neuroprotective effects. In this study, the main purpose is to investigate whether fasudil has beneficial effects on cognitive impairment and neuronal toxicity induced by Aβ.

METHODS AND RESULTS

In the present study, intracerebroventricular injection of Aβ1-42 to rats resulted in marked cognitive impairment, severe neuronal damage, as well as increased IL-1β, tumor necrosis factor alpha (TNF-α) production, and NF-κB activation. Administration of fasudil significantly ameliorated the spatial learning and memory impairment, attenuated neuronal loss, and neuronal injury induced by Aβ1-42 . In addition, fasudil inhibited IL-1β and TNF-α production and NF-κB activation in the rat brain.

CONCLUSIONS

Fasudil can protect against Aβ-induced hippocampal neurodegeneration by suppressing inflammatory response, suggesting that fasudil might be a promising agent for the prevention and treatment of inflammation-related diseases, such as AD.

Involvement of Nrf2-mediated upregulation of heme oxygenase-1 in mollugin-induced growth inhibition and apoptosis in human oral cancer cells

Although previous studies have shown that mollugin, a bioactive phytochemical isolated from Rubia cordifolia L. (Rubiaceae), exhibits antitumor effects, its biological activity in oral cancer has not been reported. We thus investigated the effects and putative mechanism of apoptosis induced by mollugin in human oral squamous cell carcinoma cells (OSCCs). Results show that mollugin induces cell death in a dose-dependent manner in primary and metastatic OSCCs. Mollugin-induced cell death involved apoptosis, characterized by the appearance of nuclear shrinkage, flow cytometric analysis of sub-G₁ phase arrest, and annexin V-FITC and propidium iodide staining. Western blot analysis and RT-PCR revealed that mollugin suppressed activation of NF-κB and NF-κB-dependent gene products involved in antiapoptosis (Bcl-2 and Bcl-xl), invasion (MMP-9 and ICAM-1), and angiogenesis (FGF-2 and VEGF). Furthermore, mollugin induced the activation of p38, ERK, and JNK and the expression of heme oxygenase-1 (HO-1) and nuclear factor E2–related factor 2 (Nrf2). Mollugin-induced growth inhibition and apoptosis of HO-1 were reversed by an HO-1 inhibitor and Nrf2 siRNA. Collectively, this is the first report to demonstrate the effectiveness of mollugin as a candidate for a chemotherapeutic agent in OSCCs via the upregulation of the HO-1 and Nrf2 pathways and the downregulation of NF-κB.

Synthesizing oncogenic signal-processing systems that function as both "signal counters" and "signal blockers" in cancer cells

RNA-protein interaction plays a significant role in regulating eukaryotic translation. This phenomenon raises questions about the ability of artificial biological systems to take the advantage of protein-RNA interaction. Here, we designed an oncogenic signal-processing system expressing both a Renilla luciferase reporter gene controlled by RNA-protein interaction in its 5'-untranslated region (5'-UTR) and a Firefly luciferase normalization gene. To test the ability of the designed system, we then constructed vectors targeting the nuclear factor-κB (NF-κB) or the β-catenin signal. We found that the inhibition (%) of luciferase expression was correlated to the targeted protein content, allowing quantitative measurement of oncogenic signal intensity in cancer cells. The systems inhibited the expression of oncogenic signal downstream genes and induced bladder cancer cell proliferation inhibition and apoptosis without affecting normal urothelial cells. Compared to traditional methods (ELISA and quantitative immunoblotting), the bio-systems provided highly accurate, consistent, and reproducible quantification of protein signals and were able to discriminate between cancerous and non-cancerous cells. In conclusion, the synthetic systems function as both "signal counters" and "signal blockers" in cancer cells. This approach provides a synthetic biology platform for oncogenic signal measurement and cancer treatment.

Role of NF-κB as a Prognostic Marker in Breast Cancer : A Pilot Study in Indian Patients

The nuclear factor κB (NF-κB) is a superfamily of transcription factors. It plays an important role in development & progression of cancer. This study was conducted in a tertiary care centre to investigate the significance of NF-κB as a prognostic marker in breast cancer and study its relation with established prognostic markers such as tumor grade, lymph node status, hormone receptor & HER-2/neu expression. We measured NF-κB expression of breast cancer tissue as a test sample & from fibroadenoma as a control. Measurement was done by Western Blot Technique using p65 protein of NF-κB super family of transcription factors. ER,PR and HER-2/neu were measured by immunohistochemistry methods. NF-κB/p65 is significantly associated with large tumor size (≥5 cm), high grade tumors, negative ER, negative PR, positive HER-2/neu and high NPI (≥5.4) scores. NF-κB/p65 expression implies aggressive biological behaviour of breast cancer & this study validates significant association of NF-κB /p65 overexpression with large tumor size, negative estrogen & progesterone receptor status and overexpression of c-erbB2 oncoprotein.

PMS1077 sensitizes TNF-α induced apoptosis in human prostate cancer cells by blocking NF-κB signaling pathway

Our previous studies have demonstrated that PMS1077, a platelet-activating factor (PAF) antagonist, could induce apoptosis of Raji cells. However, the mechanism of action has not yet been determined. The nuclear transcription factor-kappa B (NF-κB) signaling pathway plays a critical role in tumor cell survival, proliferation, invasion, metastasis, and angiogenesis, so we determined the effects of PMS1077 and its structural analogs on tumor necrosis factor-α (TNF-α) induced activation of NF-κB signaling. In this study, we found that PMS1077 inhibited TNF-α induced expression of the NF-κB regulated reporter gene in a dose dependent manner. Western blot assay indicated that PMS1077 suppressed the TNF-α induced inhibitor of κB-α (IκB-α) phosphorylation, IκB-α degradation, and p65 phosphorylation. PMS1077 consistently blocked TNF-α induced p65 nuclear translocation as demonstrated in the immunofluorescence assay used. Docking studies by molecular modeling predicted that PMS1077 might interact directly with the IκB kinase-β (IKK-β) subunit. These results suggested that PMS1077 might suppress the activation of NF-κB by targeting IKK-β involved in the NF-κB signaling pathway. Finally, we showed that PMS1077 sensitized cells to TNF-α induced apoptosis by suppressing the expression of NF-κB regulated anti-apoptotic genes. Our results reveal a novel function of PMS1077 on the NF-κB signaling pathway and imply that PMS1077 can be considered as an anti-tumor lead compound.

Anti-Bladder-Tumor Effect of Baicalein from Scutellaria baicalensis Georgi and Its Application In Vivo

Some phytochemicals with the characteristics of cytotoxicity and/or antimetastasis have generated intense interest among the anticancer studies. In this study, a natural flavonoid baicalein was evaluated in bladder cancer in vitro and in vivo. Baicalein inhibits 5637 cell proliferation. It arrests cells in G1 phase at 100  μ M and in S phase below 75  μ M. The protein expression of cyclin B1 and cyclin D1 is reduced by baicalein. Baicalein-induced p-ERK plays a minor role in cyclin B1 reduction. Baicalein-inhibited p65NF- κ B results in reduction of cell growth. Baicalein-induced pGSK(ser9) has a little effect in increasing cyclin B1/D1 expression instead. The translation inhibitor cycloheximide blocks baicalein-reduced cyclin B1, suggesting that the reduction is caused by protein synthesis inhibition. On the other hand, neither cycloheximide nor proteasome inhibitor MG132 completely blocks baicalein-reduced cyclin D1, suggesting that baicalein reduces cyclin D1 through protein synthesis inhibition and proteasomal degradation activation. In addition, baicalein also inhibits cell invasion by inhibiting MMP-2 and MMP-9 mRNA expression and activity. In mouse orthotopic bladder tumor model, baicalein slightly reduces tumor size but with some hepatic toxicity. In summary, these results demonstrate the anti-bladder-tumor properties of the natural compound baicalein which shows a slight anti-bladder-tumor effect in vivo.

On the increase in network robustness and decrease in network response ability during the aging process: a systems biology approach via microarray data

Aging, an extremely complex and system-level process, has attracted much attention in medical research, especially since chronic diseases are quite prevalent in the elderly population. These may be the result of both gene mutations that lead to intrinsic perturbations and environmental changes that may stimulate signaling in the body. Therefore, analysis of network robustness to tolerate intrinsic perturbations and network response ability of gene networks to respond to external stimuli during the aging process may provide insight into the systematic changes caused by aging. We first propose novel methods to estimate network robustness and measure network response ability of gene regulatory networks by using their corresponding microarray data in the aging process. Then, we find that an aging-related gene network is more robust to intrinsic perturbations in the elderly than the young, and therefore is less responsive to external stimuli. Finally, we find that the response abilities of individual genes, especially FOXOs, NF-κB, and p53, are significantly different in the young versus the aged subjects. These observations are consistent with experimental findings in the aged population, e.g., elevated incidence of tumorigenesis and diminished resistance to oxidative stress. The proposed method can also be used for exploring and analyzing the dynamic properties of other biological processes via corresponding microarray data to provide useful information on clinical strategy and drug target selection.

The Herbal Drug Melampyrum pratense L. (Koch): Isolation and Identification of Its Bioactive Compounds Targeting Mediators of Inflammation

Melampyrum pratense L. (Koch) is used in traditional Austrian medicine for the treatment of different inflammation-related conditions. In this work, we show that the extracts of M. pratense stimulated peroxisome proliferator-activated receptors- (PPARs-)α and -γ that are well recognized for their anti-inflammatory activities. Furthermore, the extract inhibited the activation of the proinflammatory transcription factor NF-κB and induction of its target genes interleukin-8 (IL-8) and E-selectin in vitro. Bioassay-guided fractionation identified several active flavonoids and iridoids including melampyroside and mussaenoside and the phenolic compound lunularin that were identified in this species for the first time. The flavonoids apigenin and luteolin were distinguished as the main components accountable for the anti-inflammatory properties. Apigenin and luteolin effectively inhibited tumor necrosis factor α (TNF-α)-induced NF-κB-mediated transactivation of a luciferase reporter gene. Furthermore, the two compounds dose-dependently reduced IL-8 and E-selectin protein expression after stimulation with lipopolysaccharide (LPS) or TNF-α in endothelial cells (ECs). The iridoids melampyroside and mussaenoside prevented the elevation of E-selectin in LPS-stimulated ECs. Lunularin was found to reduce the protein levels of the proinflammatory mediators E-selectin and IL-8 in ECs in response to LPS. These data validate the ethnomedical use of M. pratense for the treatment of inflammatory conditions and point to the constituents accountable for its anti-inflammatory activity.

A dual-regulated oncolytic adenovirus expressing interleukin-24 sensitizes melanoma cells to temozolomide via the induction of apoptosis

Malignant melanoma is one of the most lethal and aggressive human malignancies. Suppressed apoptosis and extraordinary invasiveness are the distinctive features that contribute to malignant melanoma. The alkylating agent temozolomide (TMZ) is one of the most effective single chemotherapeutic agents for patients with malignant melanoma, but resistance develops quickly and with high frequency. We constructed a dual-regulated oncolytic adenovirus expressing interleukin 24 (IL-24) gene (Ki67-ZD55-IL-24) by utilizing the Ki67 promoter to replace the native viral promoter of E1A gene. We investigated whether a combination of Ki67-ZD55-IL-24-mediated gene virotherapy and chemotherapy using TMZ produces increased cytotoxicity against human melanoma cells via the induction of apoptosis. Our data indicate that this novel strategy thus holds promising potentials for further developing an effective approach to treat malignant melanoma.