Eicosanoids in inflammation and cancer: the role of COX-2

Chalcone derivatives' interaction with human serum albumin and cyclooxygenase-2

Chalcone derivatives are an extremely valuable class of compounds, primarily due to the keto-ethylenic group, CO-CH[double bond, length as m-dash]CH-, they contain. Moreover, the presence of a reactive α,β-unsaturated carbonyl group confers upon them a broad range of pharmacological properties. Recent developments in heterocyclic chemistry have led to the synthesis of chalcone derivatives, which have been biologically investigated for their activity against certain diseases. In this study, we investigated the binding of new chalcone derivatives with COX-2 (cyclooxygenase-2) and HSA (Human Serum Albumin) using spectroscopic and molecular modeling studies. COX-2 is commonly found in cancer and plays a role in the production of prostaglandin E (2), which can help tumors grow by binding to receptors. HSA is the most abundant protein in blood plasma, and it transports various compounds, including hormones and fatty acids. The conformation of chalcone derivatives in the HSA complex system was established through fluorescence steady and excited state spectroscopy techniques and FTIR analyses. To gain a more comprehensive understanding, molecular docking, and dynamics were conducted on the target protein (COX-2) and transport protein (HSA). In addition, we conducted density-functional theory (DFT) and single-point DFT to understand intermolecular interaction in protein active sites.

An extensive review on phenolic compounds and their potential estrogenic properties on skin physiology

Polyphenolic compounds constitute a diverse group of natural components commonly occurring in various plant species, known for their potential to exert both beneficial and detrimental effects. Additionally, these polyphenols have also been implicated as endocrine-disrupting (ED) chemicals, raising concerns about their widespread use in the cosmetics industry. In this comprehensive review, we focus on the body of literature pertaining to the estrogenic properties of ED chemicals, with a particular emphasis on the interaction of isoflavones with estrogen receptors. Within this review, we aim to elucidate the multifaceted roles and effects of polyphenols on the skin, exploring their potential benefits as well as their capacity to act as ED agents. By delving into this intricate subject matter, we intend to provoke thoughtful consideration, effectively opening a Pandora's box of questions for the reader to ponder. Ultimately, we invite the reader to contemplate whether polyphenols should be regarded as friends or foes in the realm of skincare and endocrine disruption.

Sulindac sulfide as a non-immune suppressive γ-secretase modulator to target triple-negative breast cancer

Introduction

Triple-negative breast cancer (TNBC) comprises a heterogeneous group of clinically aggressive tumors with high risk of recurrence and metastasis. Current pharmacological treatment options remain largely limited to chemotherapy. Despite promising results, the efficacy of immunotherapy and chemo-immunotherapy in TNBC remains limited. There is strong evidence supporting the involvement of Notch signaling in TNBC progression. Expression of Notch1 and its ligand Jagged1 correlate with poor prognosis. Notch inhibitors, including g-secretase inhibitors (GSIs), are quite effective in preclinical models of TNBC. However, the success of GSIs in clinical trials has been limited by their intestinal toxicity and potential for adverse immunological effects, since Notch plays key roles in T-cell activation, including CD8 T-cells in tumors. Our overarching goal is to replace GSIs with agents that lack their systemic toxicity and ideally, do not affect tumor immunity. We identified sulindac sulfide (SS), the active metabolite of FDA-approved NSAID sulindac, as a potential candidate to replace GSIs.

Methods

We investigated the pharmacological and immunotherapeutic properties of SS in TNBC models in vitro, ex-vivo and in vivo.

Results

We confirmed that SS, a known γ-secretase modulator (GSM), inhibits Notch1 cleavage in TNBC cells. SS significantly inhibited mammosphere growth in all human and murine TNBC models tested. In a transplantable mouse TNBC tumor model (C0321), SS had remarkable single-agent anti-tumor activity and eliminated Notch1 protein expression in tumors. Importantly, SS did not inhibit Notch cleavage in T- cells, and the anti-tumor effects of SS were significantly enhanced when combined with a-PD1 immunotherapy in our TNBC organoids and in vivo.

Discussion

Our data support further investigation of SS for the treatment of TNBC, in conjunction with chemo- or -chemo-immunotherapy. Repurposing an FDA-approved, safe agent for the treatment of TNBC may be a cost-effective, rapidly deployable therapeutic option for a patient population in need of more effective therapies.

Dual inhibition of cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX) by resveratrol derivatives in cancer therapy: in silico approach

In a number of human cancers, both cycloxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX) are up-regulated and co-expressed, promoting cancer cell proliferation and angiogenesis. Resveratrol (3,4',5-trihydroxy-trans-stilbene) is a natural polyphenolic phytoalexin found in a variety of plants that influences various signal-transduction pathways which control apoptosis, cell growth and cell division, metastasis, angiogenesis and inflammation, and has an impact on cancer stages ranging from initiation to progression. In this work, molecular docking and molecular dynamics simulation method are employed to design resveratrol derivatives for COX-2 and 5-LOX enzymes. By attaching several functional groups on four different places of the resveratrol scaffold, the R group enumeration approach was employed to build four libraries of resveratrol derivatives. Thus, R group enumeration is done to focus on the enhancement of potency of compounds and other chemical characteristics like solubility. Drug-like filters such as REOS 1, 2, 3 and PAINS were applied to the libraries, generating a total of 5557 compounds. Drug-like filters such as REOS and PAINS-1, 2 and 3 were applied to the libraries, generating a total of 5557 compounds. All of these compounds were docked with both enzymes using the Glide SP and XP docking methods. Enrichment calculations were performed using 40 compounds from XP docking along with resveratrol, and 1000 decoy compounds from the DUD-E database to validate the docking protocol. The stability of the complexes was further studied using molecular dynamics simulation, radius of gyration, MM/GBSA, H bond monitoring and electrostatic potential surface (EPS). ADMET properties of compounds were studied using SwissADME and pkCSM server.Communicated by Ramaswamy H. Sarma.

Crossroad between the Heat Shock Protein and Inflammation Pathway in Acquiring Drug Resistance: A Possible Target for Future Cancer Therapeutics

The development of multidrug resistance (MDR) against chemotherapeutic agents has become a major impediment in cancer therapy. Understanding the underlying mechanism behind MDR can guide future treatment for cancer with better therapeutic outcomes. Recent studies evidenced that crossroads interaction between the heat shock proteins (HSP) and inflammatory responses under the tumor microenvironment plays a pivotal role in modulating drug responsiveness and drug resistance through a complex cytological process. This review aims to investigate the interrelationship between inflammation and HSP in acquiring multiple drug resistance and investigate strategies to overcome the drug resistance to improve the efficacy of cancer treatment. HSP plays a dual regulatory effect as an immunosuppressive and immunostimulatory agent, involving the simultaneous blockade of multiple signaling pathways in acquiring MDR. For example, HSP27 shows biological effects on monocytes by causing IL10 and TNFα secretion and blocking monocyte differentiation to normal dendritic cells and tumor-associated macrophages to promote cancer progression and chemoresistance. Thus, the HSP function and immune-checkpoint release modalities provide a therapeutic target for a therapeutically beneficial approach for enhancing anti-tumor immune responses. The interconnection between inflammation and HSP, along with the tumor microenvironment in acquiring drug resistance, has become crucial for rationalizing the effect of HSP immunomodulatory activity with immune checkpoint blockade. This relationship can overcome drug resistance and assist in the development of novel combinatorial cancer immunotherapy in fighting cancer with decreasing mortality rates.

Purification and activity evaluation of novel anti-inflammatory peptides from pearl oyster (Pinctada martensii) hydrolysates

Pearl oyster meat, a by-product of pearl production, is rich in protein, but has a low utilization rate. Our previous study showed that pearl oyster meat hydrolysates have potential anti-inflammatory activity. In this study, highly active peptides from pearl oyster meat hydrolysates were purified, identified, and extracted, and their anti-inflammatory activity was further investigated. A total of 206 peptides were identified, and three novel anti-inflammatory peptides, TWP (402.1903 Da), TAMY (484.1992 Da) and FPGA (390.1903 Da), were screened by molecular docking. The molecular docking results showed that TWP, TAMY and FPGA can bind to key regions in the cyclooxygenase-2 (COX-2) active site. Furthermore, the three anti-inflammatory peptides can effectively regulate the release of inflammatory mediators from RAW264.7 macrophages by reducing the levels of nitric oxide (NO) and pro-inflammatory cytokines (such as TNF-α, IL-6 and IL-1β), and increasing the production of anti-inflammatory cytokine IL-10, showing great anti-inflammatory activity. This study provides a new theoretical reference for the development of functional foods or nutritional supplements with natural anti-inflammatory effects.

Exploring the potential effect of phospholipase A2 antibody to extend beef shelf-life in a beef liposome model system

The objective of this study was to elucidate the effect of phospholipase A2 (PLA2) and a PLA2 antibody (aPLA2) on phospholipid (PL) hydrolysis in beef and to understand how the altered PL composition may affect lipid oxidation and antioxidant capacity of beef in an in vitro system. Various combinations of PLA2 and aPLA2 were introduced to a beef liposome model system and exposed to a retail display. The PL and free fatty acid (FFA) profiles, antioxidant capacity and lipid oxidation were measured for the liposome system. Key PL classes were reduced and the release of polyunsaturated FFAs was increased with the inclusion of PLA2 in the treatments (P < 0.05). There was no inhibition of PL hydrolysis with the addition of aPLA2. PLA2 showed strong antioxidant capacity in the liposome system (P < 0.01), but lipid oxidation still increased in samples treated with PLA2 throughout the retail display (P < 0.01). Finally, aPLA2 treatments demonstrated potential to decrease lipid oxidation (P < 0.01).

Bioassay-Guided Isolation of Anti-Inflammatory Constituents of the Subaerial Parts of Cyperus articulatus (Cyperaceae)

Based on data from a previous ethnobotanical study in northern Angola, phytochemical investigations into the methanolic rhizomes and roots extract of Cyperus articulatus, monitored by in vitro assays, resulted in the recovery of 12 sesquiterpenes, 3 stilbenes, 2 phenolic acids, 1 monoterpene, and 1 flavonoid. Among them, 14 compounds were isolated for the first time from this species. Their inhibitory potential against nitric oxide (NO) production, as well as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression, was evaluated in LPS-treated J774A.1 murine macrophages. Especially, both stilbene dimer trans-scirpusin B and trimer cyperusphenol B showed promising inhibitory activity against the production of the inflammatory mediator, NO, in a concentration-dependent manner (10−1 µM). The obtained data are the first results confirming the anti-inflammatory potential of C. articulatus and support its indigenous use as a traditional remedy against inflammation-related disorders.

Chemo-photodynamic Activity of Silicon Phthalocyanines Bearing Cyclooxygenase Inhibitors on Colorectal Cancer Cell Lines

Colorectal cancer ranks as the third most lethal cancer worldwide, resulting in over 1 million cases and 900 000 deaths per year. According to population-based studies, administration of long-term non-steroidal anti-inflammatory drugs (NSAIDs) was proven to reduce the risk of a subject developing colorectal cancer. In the present study, the anti-cancer activity of two different NSAIDs, sulindac- (Pc-1) or diclofenac-substituted (Pc-2) asymmetric silicon phthalocyanine derivatives, was evaluated in four different colorectal cancer cell lines bearing various carcinogenic mutations. In this context, the IC₅₀ values of each compound after 24 and 48 h were determined on HCT116, SW480, LoVo, and HT29 cell lines, and the effects of the compounds on programmed cell death pathways apoptosis and autophagy, their impact on cell cycle progression, and the effect of NSAID moieties they bear on COX-1 and COX-2 proteins were analyzed. In addition, the photophysical and photochemical properties of a synthesized Pc derivative bearing axial diclofenac and triethylene glycol groups (Pc-2) have been investigated, and the compound has been characterized by using different analytical techniques. Our results indicated that both compounds inhibit COX protein expression levels, activate apoptosis in all cell lines, and lead to cell cycle arrest in the G2/M phase, depending on the COX expression profiles of the cell lines, indicating that NSAIDs can be coupled with Pc's to achieve increased anti-cancer activity, especially on cancer cells known to have high COX activity.

Inhibition of DDX3 and COX-2 by forskolin and evaluation of anti-proliferative, pro-apoptotic effects on cervical cancer cells: molecular modelling and in vitro approaches

Several studies have reported up-regulation of both cyclooxygenase-2 (COX-2) and DEAD-box RNA helicase3 (DDX3) and have validated their oncogenic role in many cancers. Inhibition of COX-2 and DDX3 offers a potential pharmacological strategy for prevention of cancer progression. The COX-2 isoform is expressed in response to pro-inflammatory stimuli in premalignant lesions, including cervical tissues. This study elucidates the potential role of plant derived compound Forskolin (FSK) in plummeting the expression of COX-2 and DDX3 in cervical cancer. To establish this, the cervical cancer cells were treated with the FSK compound which induced a dose dependent significant inhibition of COX-2 and DDX3 expression. The FSK treatment also significantly induced apoptosis in cancer cells by modulating the expression of apoptotic markers like caspase-3, cleaved caspase-3, caspase-9, cleaved caspase-9, full length-poly ADP ribose polymerase (PARP), cleaved-poly ADP ribose polymerase (C-PARP) and Bcl2 in dose dependent manner. Further FSK significantly modulated the cell survival pathway Phosphatidylinositol 3-kinase (PI3-K)/Akt signalling pathway upon 24 h of incubation in cervical cancer cells. The molecular docking studies revealed that the FSK engaged the active sites of both the targets by interacting with key residues.

COVID-19 and cancer: start the resolution!

Coronavirus disease 2019 (COVID-19) due to infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been an ongoing pandemic causing significant morbidity and mortality worldwide. The “cytokine storm” is a critical driving force in severe COVID-19 cases, leading to hyperinflammation, multi-system organ failure, and death. A paradigm shift is emerging in our understanding of the resolution of inflammation from a passive course to an active biochemical process driven by endogenous specialized pro-resolving mediators (SPMs), such as resolvins, protectins, lipoxins, and maresins. SPMs stimulate macrophage-mediated debris clearance and counter pro-inflammatory cytokine production, a process collectively termed as the “resolution of inflammation.” Hyperinflammation is not unique to COVID-19 and also occurs in neoplastic conditions, putting individuals with underlying health conditions such as cancer at elevated risk of severe SARS-CoV-2 infection. Despite approaches to block systemic inflammation, there are no current therapies designed to stimulate the resolution of inflammation in patients with COVID-19 or cancer. A non-immunosuppressive therapeutic approach that reduces the cytokine storm in patients with COVID-19 and cancer is urgently needed. SPMs are potent immunoresolvent and organ-protective lipid autacoids that stimulate the resolution of inflammation, facilitate clearance of infections, reduce thrombus burden, and promote a return to tissue homeostasis. Targeting endogenous lipid mediators, such as SPMs, offers an entirely novel approach to control SARS-CoV-2 infection and cancer by increasing the body’s natural reserve of pro-resolving mediators without overt toxicity or immunosuppression.

Inflammation, It's Regulation and Antiphlogistic Effect of the Cyanogenic Glycoside Amygdalin

The inflammatory reaction accompanies in part or in full any disease process in the vascularized metazoan. This complicated reaction is controlled by regulatory mechanisms, some of which produce unpleasant symptomatic manifestations of inflammation. Therefore, there has been an effort to develop selective drugs aimed at removing pain, fever, or swelling. Gradually, however, serious adverse side effects of such inhibitors became apparent. Scientific research has therefore continued to explore new possibilities, including naturally available substances. Amygdalin is a cyanogenic glycoside present, e.g., in bitter almonds. This glycoside has already sparked many discussions among scientists, especially about its anticancer potential and related toxic cyanides. However, toxicity at different doses made it generally unacceptable. Although amygdalin given at the correct oral dose may not lead to poisoning, it has not yet been accurately quantified, as its action is often affected by different intestinal microbial consortia. Its pharmacological activities have been studied, but its effects on the body's inflammatory response are lacking. This review discusses the chemical structure, toxicity, and current knowledge of the molecular mechanism of amygdalin activity on immune functions, including the anti-inflammatory effect, but also discusses inflammation as such, its mediators with diverse functions, which are usually targeted by drugs.

Apigenin-Loaded PLGA-DMSA Nanoparticles: A Novel Strategy to Treat Melanoma Lung Metastasis

The flavone apigenin (APG), alone as well as in combination with other chemotherapeutic agents, is known to exhibit potential anticancer effects in various tumors and inhibit growth and metastasis of melanoma. However, the potential of apigenin nanoparticles (APG-NPs) to prevent lung colonization of malignant melanoma has not been well investigated. APG-loaded PLGA-NPs were surface-functionalized with meso-2,3-dimercaptosuccinic acid (DMSA) for the treatment of melanoma lung metastasis. DMSA-conjugated APG-loaded NPs (DMSA-APG-NPs) administered by an oral route exhibited sustained APG release and showed considerable enhancement of plasma half-life, C_max value, and bioavailability compared to APG-NPs both in plasma and the lungs. DMSA-conjugated APG-NPs showed comparably higher cellular internalization in B16F10 and A549 cell lines compared to that of plain NPs. Increased cytotoxicity was observed for DMSA-APG-NPs compared to APG-NPs in A549 cells. This difference between the two formulations was lower in B16F10 cells. Significant depolarization of mitochondrial transmembrane potential and an enhanced level of caspase activity were observed in B16F10 cells treated with DMSA-APG-NPs compared to APG-NPs as well. Western blot analysis of various proteins was performed to understand the mechanism of apoptosis as well as prevention of melanoma cell migration and invasion. DMSA conjugation substantially increased accumulation of DMSA-APG-NPs given by an intravenous route in the lungs compared to APG-NPs at 6 and 8 h. This was also corroborated by scintigraphic imaging studies with radiolabeled formulations administered by an intravenous route. Conjugation also allowed comparatively higher penetration as evident from an in vitro three-dimensional tumor spheroid model study. Finally, the potential therapeutic efficacy of the formulation was established in experimental B16F10 lung metastases, which suggested an improved bioavailability with enhanced antitumor and antimetastasis efficacy of DMSA-conjugated APG-NPs following oral administration.

Overview on the Discovery and Development of Anti-Inflammatory Drugs: Should the Focus Be on Synthesis or Degradation of PGE2?

Inflammation is a protective response that develops against tissue injury and infection. Chronic inflammation, on the other hand, is the key player in the pathogenesis of many inflammatory disorders including cancer. The cytokine storm, an inflammatory response flaring out of control, is mostly responsible for the mortality in COVID-19 patients. Anti-inflammatory drugs inhibit cyclooxygenases (COX), which are involved in the biosynthesis of prostaglandins that promote inflammation. The conventional non-steroidal anti-inflammatory drugs (NSAIDs) are associated with gastric and renal side-effects, as they inhibit both the constitutive COX-1 and the inducible COX-2. The majority of selective COX-2 inhibitors (COXIBs) are without gastric side-effects but are associated with cardiac side-effects on long-term use. The search for anti-inflammatory drugs without side-effects, therefore, has become a dream and ongoing effort of the Pharma companies. As PGE₂ is the key mediator of inflammatory disorders, coming up with a strategy to reduce the levels of PGE₂ alone without affecting other metabolites may form a better choice for the development of next generation anti-inflammatory drugs. In this direction the options being explored are on synthesis of PGE₂-mPGES-1; PGE₂ degradation through a specific PG dehydrogenase, 15-PGDH, and by blocking its activity mediated through a specific PGE receptor, EP4. As leukotrienes formed via the 5-lipoxygenase (5-LOX) pathway also play an important role in the mediation of inflammation, efforts are also being made to target both COX and LOX pathways. This review focuses on addressing the following three points: 1) How NSAIDs and COXIBs are associated with gastric, renal and cardiac side-effects; 2) Should the focus be on the targets upstream or downstream of PGE₂; and 3) the status of alternative targets being explored for the discovery and development of anti-inflammatory drugs without side-effects.

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Efficacy of thymoquinone in the treatment of experimental lipopolysaccharide-induced acute lung injury

Introduction

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are acute onset syndromes affecting the lungs, which develop for several reasons and are characterized by hypoxemia and diffuse lung infiltration. The activity of thymoquinone (TQ) is known in acute lung injury. It is considered that it could be effective in ALI/ARDS treatment by ensuring possible COX-2 inhibition.

Aim

By this study was to show the protective activity of TQ in lipopolysaccharide (LPS) induced acute lung injury.

Material and methods: A total of 28 BALB/c male mice were randomized to 4 groups of 7 as the Control group, TQ group (3 mg/kg), LPS group (5 mg/kg) and TQ treatment group. TQ was administered intraperitoneally 1 hour before the intratracheal administration of LPS (5 mg/kg). The mice were sacrificed 6 hours after the LPS administration and the lungs were extracted for histopathological examination. All experimental procedures complied with the requirements of the Animal Care and Ethics Committee of Dokuz Eylul University.

Results

When all the study groups were compared, significant differences were found between the groups in terms of the degrees of neutrophil migration (p = 0.042), intra-alveolar hemorrhage (p = 0.004) and alveolar destruction (p < 0.0006). A significant recovery was observed in the lung histopathological changes (neutrophil migration, intra-alveolar hemorrhage and alveolar destruction) in the TQ treatment group.

Conclusions

The results of this study showed that TQ may have a protective effect against LPS-induced acute lung injury. The possible mechanism could be considered to be cyclooxygenase 2 (COX-2) inhibition.

Development and validation of a rapid, specific and sensitive LC-MS/MS bioanalytical method for eicosanoid quantification - assessment of arachidonic acid metabolic pathway activity in hypertensive rats

Lipid mediators such as eicosanoids maintain various physiological processes, and their alterations are involved in the development of numerous cardiovascular diseases. Therefore, the reliable assessment of their profile could be helpful in diagnosis as well as in eicosanoid biomarker-based treatment. Hence, the presented study aimed to develop and validate a new rapid, specific and sensitive LC-MS/MS method for quantification of arachidonic acid-derived eicosanoids in plasma, including lipid mediators generated via COX-, LOX- and CYP450-dependent pathways. The developed method features high sensitivity because the lower limit of quantification ranged from 0.05 to 0.50 ng mL^-1 as well as the accuracy and precision estimated within 88.88-111.25% and 1.03-11.82%, respectively. An application of a simple and fast liquid-liquid extraction procedure for sample cleaning resulted in a highly satisfactory recovery of the analytes (>88.30%). Additionally, the method was validated using artificial plasma, an approach that enabled the elimination of the matrix effect caused by an endogenous concentration of studied lipid mediators. Importantly, the presented LC-MS/MS method allowed for simultaneous quantitative and qualitative [quan/qual] analysis of the selected eicosanoids, leading to an additional improvement of the method specificity. Moreover, the validated method was successfully applied for eicosanoid profiling in rat, mouse and human plasma samples, clearly demonstrating the heterogeneity of the profile of studied lipid mediators in those species.

Current Anti-Inflammatory Therapies and the Potential of Secretory Phospholipase A2 Inhibitors in the Design of New Anti-Inflammatory Drugs: A Review of 2012 - 2018

The inflammatory process is a natural self-defense response of the organism to damage agents and its action mechanism involves a series of complex reactions. However, in some cases, this process can become chronic, causing much harm to the body. Therefore, over the years, many anti-inflammatory drugs have been developed aiming to decrease the concentrations of inflammatory mediators in the organism, which is a way of controlling these abnormal chain reactions. The main target of conventional anti-inflammatory drugs is the cyclooxygenase (COX) enzyme, but its use implies several side effects. Thus, based on these limitations, many studies have been performed, aiming to create new drugs, with new action mechanisms. In this sense, the phospholipase A2 (PLA2) enzymes stand out. Among all the existing isoforms, secretory PLA2 is the major target for inhibitor development, since many studies have proven that this enzyme participates in various inflammatory conditions, such as cancer, Alzheimer and arthritis. Finally, for the purpose of developing anti-inflammatory drugs that are sPLA2 inhibitors, many molecules have been designed. Accordingly, this work presents an overview of inflammatory processes and mediators, the current available anti-inflammatory drugs, and it briefly covers the PLA2 enzymes, as well as the diverse structural array of the newest sPLA2 inhibitors as a possible target for the production of new anti-inflammatory drugs.

Antitumor activity of Cuphea ignea extract against benzo(a)pyrene-induced lung tumorigenesis in Swiss Albino mice

Lung cancer has one of the highest mortality rates among various types of cancer and is the most frequent cancer in the world. The incidence of lung cancer is increasing rapidly, in parallel with an increased incidence of smoking. Effective chemoprevention may be an alternative strategy to control the incidence of lung cancer. Thus, the objective of current work was to ascertain the possible preventive and therapeutic efficacies of Cuphea ignea extract in a mouse model of lung tumorigenesis and its cytotoxicity toward the A549 human lung cancer cell line. Lung tumorigenesis was induced by the oral administration of benzo(a)pyrene (50 mg/kg b.w.) twice per week to Swiss albino mice for 4 weeks. Benzo(a)pyrene-treated mice were orally administered C. ignea (300 mg/kg body weight, 5 days/week) for 2 weeks before or 9 weeks after the first benzo(a)pyrene dose, for a total of 21 weeks. At the end of the administration period, various parameters were measured in the serum and lung tissues. The results revealed that the oral administration of benzo(a)pyrene resulted in increases in relative lung weight, serum levels of tumor markers (ADA, AHH, and LDH), and the inflammatory marker NF-κB, and a decreased total antioxidant capacity compared with the control. In addition, decreased levels of enzymatic and non-enzymatic antioxidants, with a concomitant increase in lipid peroxidation, metalloproteinases (MMP-2 and MMP-12), and the angiogenic marker VEGF were detected in lung tissues. Moreover, benzo(a)pyrene administration induced the upregulation of PKCα, COX-2, and Bcl-2 expression, with the downregulation of BAX and caspase-3 expression. C. ignea treatment alleviated all alterations in these parameters, which was further confirmed by the histopathological analysis of lung tissues. The findings of the current work provide the first verification of the preventive and therapeutic potentials of C. ignea extract against benzo(a)pyrene-induced lung tumorigenesis in mice.

Inflammatory pathway interactions and cancer multidrug resistance regulation

Multidrug resistances against chemotherapeutics are among the major challenges related to cancer treatment. Recent studies have demonstrated that different conditions may tune the expression and activity of MDR transporters. For instance, inflammation occurs through a complex cytological process and chemical reactions in the most tumor microenvironment; it can play a critical role in cancer development and is capable of altering the expression and function of MDR transporters. Cytokines, interleukins, and prostaglandins are potent inflammatory mediators that can modulate the expression of MDRs at transcriptional and post-transcriptional levels in the most human cancer cells and tissues and potentially contribute to balance bioavailability of chemotherapeutic agents. Since cancer cases are usually accompanied by inflammatory responses, glucocorticoids and NSAIDs are the primary useful combination chemotherapies in a variety of cancer treatment protocols. In addition to the anti-inflammatory activities of these agents, they exert diverse modulatory effects on MDR-mediated drug resistance via specific mechanisms. Several factors, including cell and MDR-protein types, pharmacokinetics, and pharmacogenetics, mainly influence the regulatory mechanisms. Uncovering the networks between inflammation and multidrug resistance will be clinically helpful in the treatment of malignant cancers and decreasing the cancer mortality rates.

Multi-pathway integrated adjustment mechanism of licorice flavonoids presenting anti-inflammatory activity

Glycyrrhiza, commonly known as licorice, is a herbal medicine that has been used for thousands of years. Licorice contains multiple flavonoids, which possess a variety of biological activities. On the basis of the anti-inflammatory effects of licorice flavonoids, the potential mechanism of action was investigated via a plasma metabolomics approach. A total of 9 differential endogenous metabolites associated with the therapeutic effect of licorice flavonoids were identified, including linoleic acid, sphingosine, tryptophanamide, corticosterone and leukotriene B4. Besides classical arachidonic acid metabolism, metabolism of sphingolipids, tryptophan and fatty acids, phospholipids synthesis, and other pathways were also involved. The multi-pathway integrated adjustment mechanism of licorice flavonoid action may reduce side effects in patients, along with any anti-inflammatory functions, which provides a foundation for identifying and developing novel, high-potential natural drugs with fewer side effects for clinical application.

Stress, inflammation, and eicosanoids: an emerging perspective

Clinical and experimental studies support the notion that adrenergic stimulation and chronic stress affect inflammation, metabolism, and tumor growth. Eicosanoids are also known to heavily influence inflammation while regulating certain stress responses. However, additional work is needed to understand the full extent of interactions between the stress-related pathways and eicosanoids. Here, we review the potential influences that stress, inflammation, and metabolic pathways have on each other, in the context of eicosanoids. Understanding the intricacies of such interactions could provide insights on how systemic metabolic effects mediated by the stress pathways can be translated into therapies for cancer and other diseases.

Omega-3 Polyunsaturated Fatty Acid Derived Lipid Mediators and their Application in Drug Discovery

Omega-3 (n-3) and omega-6 (n-6) polyunsaturated fatty acids (PUFAs) play crucial and often opposing regulatory roles in health and in pathological conditions. n-3 and n-6 PUFA undergo biotransformation to parallel series of lipid mediators that are potent modulators of many cellular processes. A wide range of biological actions have been attributed to lipid mediators derived from n-6 PUFA, and these mediators have served as lead compounds in the development of numerous clinically approved drugs, including latanoprost (Xalatan: Pfizer), which is listed on the WHO Model List of Essential Medicines. n-3 PUFA-derived mediators have received less attention, in part because early studies suggested that n-3 PUFA act simply as competitive substrates for biotransformation enzymes and decrease the formation of n-6 PUFA-derived lipid mediators. However, more recent studies suggest that n-3 PUFA-derived mediators are biologically important in their own right. It is now emerging that many n-3 PUFA-derived lipid mediators have potent and diverse activities that are distinct from their n-6 counterparts. These findings provide new opportunities for drug discovery. Herein, we review the biosynthesis of n-3 PUFA-derived lipid mediators and highlight their biological actions that may be exploited for drug development. Lastly, we provide examples of medicinal chemistry research that has utilized n-3 PUFA-derived lipid mediators as novel lead compounds in drug design.

Halo-Substituted Chalcones and Azachalcones-Inhibited, Lipopolysaccharited-Stimulated, Pro-Inflammatory Responses through the TLR4-Mediated Pathway

A series of B-ring, halo-substituted chalcones and azachalcones were synthesized to evaluate and compare their anti-inflammatory activity. Mouse BALB/c macrophage RAW 264.7 were pre-treated with 10 μg/mL of each compound for one hour before induction of inflammation by lipopolysaccharide (1 μg/mL) for 6 h. Some halo-chalcones and -azachalcones suppressed expression of pro-inflammatory factors toll-like receptor 4 (TLR4), IκB-α, transcription factor p65, interleukine 1β (IL-1β), IL-6, tumor necrosis factor α (TNF-α), and cyclooxygenase 2 (COX-2). The present results showed that the synthetic halo-azachalcones exhibited more significant inhibition than halo-chalcones. Therefore, the nitrogen atom in this series of azachalcones must play a more crucial role than the corresponding C-2 hydroxyl group of chalcones in biological activity. Our findings will lay the background for the future development of anti-inflammatory nutraceuticals.

Cryptotanshinone inhibits prostaglandin E2 production and COX-2 expression via suppression of TLR4/NF-κB signaling pathway in LPS-stimulated Caco-2 cells

Crytotanshinone (CTN), one of the main constituents of Salvia miltiorrhiza, has been known to exhibit antioxdative, anti-inflammatory and other important therapeutic activities. The aim of this study was to evaluate the effect of CTN on prostaglandin E2 and COX-2 production in LPS-stimulated human intestinal cells (Caco-2 cells). Caco-2 cells were stimulated with LPS in the presence or absence of CTN. The production of prostaglandin E2 (PGE₂) was detected by ELISA. The expression of COX-2 was detected by qRT-PCR and Western blot. The extent of phosphorylation of IκB-α, NF-κB p65 and the expression of TLR4 were detected by western blot. The results showed that CTN dose-dependently inhibited the expression of COX-2 both in mRNA and protein levels, resulting in a decreased production of PGE₂. We also found that CTN suppressed LPS-induced NF-κB activation and IκBα degradation. Furthermore, CTN inhibited the expression of TLR4 up-regulated by LPS. These results suggest that CTN exerts an anti-inflammatory property by inhibiting TLR4/NF-κB signaling pathway and the release of pro-inflammatory mediators. These findings suggest that CTN may be a therapeutic agent against intestinal inflammatory diseases.

In vitro functional characterization of prostaglandin-endoperoxide synthase 2 during chondrocyte hypertrophic differentiation

Cyclooxygenase 2 (Cox-2) has been implicated an essential role during bone repair, but the mechanisms remain elusive. Bone repair healing is known to include processes similar to endochondral ossification. In this study, we investigated the in vitro effect of Cox-2 on Col10a1 expression and chondrocyte hypertrophy, two critical components of endochondral ossification. Using quantitative RT-PCR, we detected increased mRNA levels of Cox-2 and Col10a1 in hypertrophic MCT cells, while cells treated with Cox-2 inhibitor, NS398, showed decreased mRNA and protein levels of Cox-2 and Col10a1. Increased Cox-2 also correlated with significantly upregulated Col10a1 in hypertrophic ATDC5 cells, whereas inhibition of Cox-2 significantly decreased Col10a1 expression. We further generated a Cox-2-expressing ATDC5 stable cell line. Compared with the controls, Cox-2 over-expression significantly increased Col10a1 as early as day 7 of continuous culturing, but not at days 14 and 21. Enhanced Alp staining was also observed in day 7 stable cell line. Correspondingly, we detected significantly increased levels of Runx2, Alp, Bcl-2, Bax, Col1a1, Osterix, and Bsp in day 7 stable line. Most of these genes have been associated with chondrocyte maturation and apoptosis. Together, our results support that Cox-2 promotes Col10a1 expression and chondrocyte hypertrophy in vitro, possibly through upregulation of Runx2 and other relevant transcription factors.

Celecoxib Enhances the Efficacy of Low-Dose Antibiotic Treatment against Polymicrobial Sepsis in Mice and Clinical Isolates of ESKAPE Pathogens

Treatment of multidrug resistant bacterial infections has been a great challenge globally. Previous studies including our study have highlighted the use of celecoxib, a non-steroidal anti-inflammatory drug in combination with antibiotic has decreased the minimal inhibitory concentration to limit Staphylococcus aureus infection. However, the efficacy of this combinatorial treatment against various pathogenic bacteria is not determined. Therefore, we have evaluated the potential use of celecoxib in combination with low doses of antibiotic in limiting Gram-positive and Gram-negative bacteria in vivo in murine polymicrobial sepsis developed by cecum ligation and puncture (CLP) method and against clinically isolated human ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species). The in vivo results clearly demonstrated a significant reduction in the bacterial load in different organs and in the inflammatory markers such as COX-2 and NF-κB via activation of SIRT1 in mice treated with imipenem, a choice of antibiotic for polymicrobial sepsis treatment. Combinatorial treatment of ampicillin and celecoxib was effective on clinical isolates of ESKAPE pathogens, 45% of tested clinical isolates showed more than 50% reduction in the colony forming units when compared to ampicillin alone. In conclusion, this non-traditional treatment strategy might be effective in clinic to reduce the dose of antibiotic to treat drug-resistant bacterial infections.

Anticonvulsive Effects of Licofelone on Status Epilepticus Induced by Lithium-pilocarpine in Wistar Rats: a Role for Inducible Nitric Oxide Synthase

Background and Purpose

Status epilepticus (SE) is a neurological disorder with high prevalence and mortality rates, requiring immediate intervention. Licofelone is a cyclooxygenase (COX) and 5-lipoxygenase (5-LOX) inhibitor, which its effectiveness to treat osteoarthritis has been approved. Increasing evidence suggests an involvement of COX and LOX enzymes in epileptic disorders. Thus, in the present study we investigate possible effects of licofelone on prevention and termination of SE. We also evaluated whether the nitrergic system could participate in this effect of licofelone.

Methods

We have utilized lithium-pilocarpine model of SE in adult Wistar rats to assess the potential effect of licofelone on seizure susceptibility. Licofelone was administered 1 h before pilocarpine. To evaluate probable role of nitric oxide (NO) system, L-arginine (60 mg/kg, i.p.), as a NO precursor; L-NAME (15 mg/kg, i.p.), as a non-selective nitric oxide synthase (NOS) inhibitor; aminoguanidine (100 mg/kg, i.p.), as an inducible NOS (iNOS) inhibitor and 7-nitroindazole (60 mg/kg, i.p.), as a neuronal NOS inhibitor were injected 15 min before licofelone. Also, licofelone and diazepam 10 mg/kg were administered 30 minutes after onset of SE.

Results

Pre-treatment with licofelone at the dosage of 10 mg/kg, significantly prevented the onset of SE in all subjects (p < 0.001). L-arginine significantly inverted this anticonvulsant effect (p < 0.05). However, L-NAME and aminoguanidine, potentiated the anticonvulsant effect of licofelone (p < 0.05, p < 0.01). Licofelone could not terminate seizures after onset which was terminated by diazepam.

Conclusions

Our findings showed that anticonvulsive effects of licofelone on SE could be mediated by iNOS. Also, we suggest that COX/5-LOX activation is possibly required in the initial stage of onset but SE recruits extra excitatory pathways with prolongation.

[Inflammation and Cancer Development in Pancreatic and Biliary Tract Cancer]

Chronic inflammation has been known to be a risk for many kinds of cancers, including pancreatic and biliary tract cancer. Recently, inflammatory process has emerged as a key mediator of cancer development and progression. Many efforts with experimental results have been given to identify the underlying mechanisms that contribute to inflammation-induced tumorigenesis. Diverse inflammatory pathways have been investigated and inhibitors for inflammation-related signaling pathways have been developed for cancer treatment. This review will summarize recent outcomes about this distinctive process in pancreatic and biliary tract cancer. Taking this evidence into consideration, modulation of inflammatory process will provide useful options for pancreatic and biliary tract cancer treatment.

Leukotriene receptor expression in esophageal squamous cell cancer and non-transformed esophageal epithelium: a matched case control study

BACKGROUND

Leukotriene B4 (LTB4R and LTB4R2) and cysteinyl leukotriene receptors (CYSLTR1 and CYSLTR2) contribute to malignant cell transformation. We aimed to investigate the expression of LTB4R, LTB4R2, CYSLTR1 and CYSLTR2 in esophageal squamous cell carcinoma and adjacent non-transformed squamous epithelium of the esophagus, as well as in control biopsy samples from esophageal squamous epithelium of patients with functional dyspepsia.

METHODS

Expression of LTB4R, LTB4R2, CYSLTR1 and CYSLTR2 was analyzed by immunohistochemistry (IHC) and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) in biopsy samples of 19 patients with esophageal squamous cell cancer and 9 sex- and age-matched patients with functional dyspepsia.

RESULTS

LTB4R, LTB4R2, CYSLTR1 and CYSLTR2 were expressed in all biopsy samples. Major findings were: 1) protein levels of all leukotriene receptors were significantly increased in esophageal squamous cell cancer compared to control mucosa (p < 0.05); 2) CYSLTR1 and CYSLTR2 gene expression was decreased in cancer tissue compared to control at 0.26-fold and 0.23-fold respectively; 3) an up-regulation of LTB4R (mRNA and protein expression) and a down-regulation of CYSLTR2 (mRNA expression) in non-transformed epithelium of cancer patients compared to control (p < 0.05) was observed.

CONCLUSIONS

The expression of leukotriene receptors was deregulated in esophageal squamous cell cancer. Up-regulation of LTB4R and down-regulation of CYSLTR2 gene expression may occur already in normal squamous esophageal epithelium of patients with esophageal cancer suggesting a potential role of these receptors in early steps of esophageal carcinogenesis. Larger studies are warranted to confirm these observations.

Potential of immunomodulatory agents as adjunct host-directed therapies for multidrug-resistant tuberculosis

Treatment of multidrug-resistant tuberculosis (MDR-TB) is extremely challenging due to the virulence of the etiologic strains of Mycobacterium tuberculosis (M. tb), the aberrant host immune responses and the diminishing treatment options with TB drugs. New treatment regimens incorporating therapeutics targeting both M. tb and host factors are urgently needed to improve the clinical management outcomes of MDR-TB. Host-directed therapies (HDT) could avert destructive tuberculous lung pathology, facilitate eradication of M. tb, improve survival and prevent long-term functional disability. In this review we (1) discuss the use of HDT for cancer and other infections, drawing parallels and the precedent they set for MDR-TB treatment, (2) highlight preclinical studies of pharmacological agents commonly used in clinical practice which have HDT potential, and (3) outline developments in cellular therapy to promote clinically beneficial immunomodulation to improve treatment outcomes in patients with pulmonary MDR-TB. The use of HDTs as adjuncts to MDR-TB therapy requires urgent evaluation.

Deciphering the mechanism behind the varied binding activities of COXIBs through Molecular Dynamic Simulations, MM-PBSA binding energy calculations and per-residue energy decomposition studies

COX-2 is a well-known drug target in inflammatory disorders. COX-1/COX-2 selectivity of NSAIDs is crucial in assessing the gastrointestinal side effects associated with COX-1 inhibition. Celecoxib, rofecoxib, and valdecoxib are well-known specific COX-2 inhibiting drugs. Recently, polmacoxib, a COX-2/CA-II dual inhibitor has been approved by the Korean FDA. These COXIBs have similar structure with diverse activity range. Present study focuses on unraveling the mechanism behind the 10-fold difference in the activities of these sulfonamide-containing COXIBs. In order to obtain insights into their binding with COX-2 at molecular level, molecular dynamics simulations studies, and MM-PBSA approaches were employed. Further, per-residue decomposition of these energies led to the identification of crucial amino acids and interactions contributing to the differential binding of COXIBs. The results clearly indicated that Leu338, Ser339, Arg499, Ile503, Phe504, Val509, and Ser516 (Leu352, Ser353, Arg513, Ile517, Phe518, Val523, and Ser530 in PGHS-1 numbering) were imperative in determining the activity of these COXIBs. The binding energies and energy contribution of various residues were similar in all the three simulations. The results suggest that hydrogen bond interaction between the hydroxyl group of Ser516 and five-membered ring of diarylheterocycles augments the affinity in COXIBs. The SAR of the inhibitors studied and the per-residue energy decomposition values suggested the importance of Ser516. Additionally, the positive binding energy obtained with Arg106 explains the binding of COXIBs in hydrophobic channel deep in the COX-2 active site. The findings of the present work would aid in the development of potent COX-2 inhibitors.

Sulindac, a non-steroidal anti-inflammatory drug, mediates breast cancer inhibition as an immune modulator

The cooperation of adaptive immunity with pharmacologic therapy influences cancer progression. Though non-steroidal anti-inflammatory drugs (NSAIDs) have a long history of cancer prevention, it is unclear whether adaptive immune system affects the action of those drugs. In present study, we revealed a novel immunological mechanism of sulindac. Our data showed that sulindac had substantial efficacy as a single agent against 4T1 murine breast cancer and prolonged the survival of tumor-bearing mice. However, in the athymic nude mice, sulindac treatment was ineffective. Further in vivo T cell subsets depletion experiments showed that CD8+ T lymphocytes deficiency reversed the anti-tumor effect of sulindac. In addition, sulindac significantly reduced M2 macrophages recruitment, cancer-related inflammation and tumor angiogenesis. Our results advance our understanding of the mechanisms of NSAIDs, and more importantly, this will provide insight into rational drug design or antitumor immunotherapy.

Dual inhibition of COX-2/5-LOX blocks colon cancer proliferation, migration and invasion in vitro

Inflammation is emerging as a new hallmark of cancer. Arachidonic acid (AA) metabolism, the family of cyclooxygenases (COXs) and lipoxygenase (LOX) play important roles in AA-related inflammatory cascades. In 94 colorectal cancer samples collected from the Han population, the immunohistochemical results indicated that 68% of the patients with colorectal cancer had a co-expression of both COX-2 and 5-LOX, while both displayed low expression in the matched normal tissues. In cell lines, three colorectal cancer cell lines exhibited high expression of COX-2 and 5-LOX. During stable silencing of the expression of COX-2 or 5-LOX in LoVo cancer cells, we found that downregulation of either COX-2 or 5-LOX significantly diminished the growth, migration and invasion of the colon cancer cells and specifically, downregulation of COX-2 could elicit upregulation of 5-LOX protein and vice versa. The above results suggested that the simultaneous blocking of COX-2 and 5-LOX activity may bring more potential benefits in managing the progression of colon cancer. Therefore, we sought to explore the effectiveness of a dual COX-2/5-LOX inhibitor darbufelone on the proliferation, migration, invasion and apoptosis of colon cancer cells, as well as the underlying mechanism of action. The results indicated that darbufelone significantly decreased the proliferative and invasive abilities of the colon cancer cells, in a dose-dependent manner. During the study of the related mechanisms, we found an upregulation of p27 and downregulation of cyclin D1 as well as CDK4 after darbufelone treatment, which indicated that darbufelone could arrest the cell cycle of LoVo cells at the G0/G1 phase. Furthermore, the activation of caspase-3 and -9, upregulation of Bax and downregulation of Bcl-2 demonstrated the occurrence of apoptosis by darbufelone. Finally, darbufelone also prevented the migration and invasion of LoVo cells, which may be ascribed to the upregulation of E-cadherin and ZO-1. In summary, our data suggest that the inhibition of both COX-2/5-LOX may be an effective therapeutic approach for colon cancer management, particularly for those patients with high expression of COX-2/5-LOX.

Design and Synthesis of Imidazopyrazolopyridines as Novel Selective COX-2 Inhibitors

The usefulness of non-steroidal anti-inflammatory drugs (NSAIDs) is hampered by their gastrointestinal side effects. Non-selective cyclooxygenases inhibitors interfere with both COX-1 and COX-2 isozymes. Since COX-1 mediates cytoprotection of gastric mucosa, its inhibition leads to the undesirable side effects. On the other hand, COX-2 is undetectable in normal tissues and selectively induced by inflammatory stimuli. Therefore, it is strongly believed that the therapeutic benefits derive from inhibition of COX-2 only. The presence of a strong connection between reported COX-2 inhibitors and cardiac toxicity encourages medicinal chemists to explore new scaffolds. In the present study, we introduced imidazopyrazolopyridines as new potent and selective COX-2 inhibitors that lack the standard pharmacophoric binding features to hERG. Starting from our lead compound 5a, structure-based drug-design was conducted and more potent analogues were obtained with high COX-2 selectivity and almost full edema protection, in carrageenan-induced edema assay, in case of compound 5e. Increased bulkiness around imidazopyrazolopyridines by adding a substituted phenyl ring(s) afforded less active compounds.

Exploration of binding site pattern in arachidonic acid metabolizing enzymes, Cyclooxygenases and Lipoxygenases

Background

Cyclooxygenase (COXs) and Lipoxygenase (LOXs) pathways are the two major enzymatic pathways in arachidonic acid (AA) metabolism. The term eicosanoid is used to describe biologically active lipid mediators including prostaglandins, thromboxanes, leukotrienes and other oxygenated derivatives, which are produced primarily from AA. Eicosanoids generated in a tissue specific manner play a key role in inflammation and cancer. As AA is the substrate common to variety of COXs and LOXs, inhibition of one pathway results in diversion of the substrate to other pathways, which often is responsible for undesirable side effects. Hence there is need for development of not only isozyme specific inhibitors but also dual/multi enzyme inhibitors. Understanding the interactions of AA and characterizing its binding sites in these enzymes therefore is crucial for developing enzyme specific and multi enzyme inhibitors for enhancing therapeutic efficacy and/or overcoming side effects.

Results

AA binding sites in COXs and LOXs are identified and compared by the development of receptor based pharmacophore using MultiBind. Physico chemical properties were compared to understand the details of the binding sites in all the enzymes and to elucidate important amino acids that can be targeted for drug design. The alignment of AA binding sites in the seven enzymes COX-1, COX-2, 5-LOX, 12-LOX, 15-LOX and plant soybean LOX-1 and LOX-3 indicated a common pattern of five common interacting groups. In the same way, comparison of AA binding sites was done pair wise and by multiple alignment in various combinations. It has been identified that aliphatic and aromatic interactions are the most common in all the enzymes. In addition interactions unique to each one of these enzymes were identified.

Conclusion

The complete analysis of AA binding sites in the seven enzymes was performed; 120 combinations for the seven enzymes were studied in detail. All the seven enzymes are structurally quite different, yet they share AA as the common binding partner. Comparisons in various combinations showed how they are similar and dissimilar with each other. This information will be helpful in designing specific as well as common inhibitors.

Electronic supplementary material

The online version of this article (doi:10.1186/s13104-015-1101-4) contains supplementary material, which is available to authorized users.

Strategies for individual phenotyping of linoleic and arachidonic acid metabolism using an oral glucose tolerance test

The ability to restore homeostasis upon environmental challenges has been proposed as a measure for health. Metabolic profiling of plasma samples during the challenge response phase should offer a profound view on the flexibility of a phenotype to cope with daily stressors. Current data modeling approaches, however, struggle to extract biological descriptors from time-resolved metabolite profiles that are able to discriminate between different phenotypes. Thus, for the case of oxylipin responses in plasma upon an oral glucose tolerance test we developed a modeling approach that incorporates a priori biological pathway knowledge. The degradation pathways of arachidonic and linoleic acids were modeled using a regression model based on a pseudo-steady-state approximated model, resulting in a parameter A that summarizes the relative enzymatic activity in these pathways. Analysis of the phenotypic parameters As suggests that different phenotypes can be discriminated according to preferred relative activity of the arachidonic and linoleic pathway. Correlation analysis shows that there is little or no competition between the arachidonic and linoleic acid pathways, although they share the same enzymes.

The spatiotemporal role of COX-2 in osteogenic and chondrogenic differentiation of periosteum-derived mesenchymal progenitors in fracture repair

Periosteum provides a major source of mesenchymal progenitor cells for bone fracture repair. Combining cell-specific targeted Cox-2 gene deletion approaches with in vitro analyses of the differentiation of periosteum-derived mesenchymal progenitor cells (PDMPCs), here we demonstrate a spatial and temporal role for Cox-2 function in the modulation of osteogenic and chondrogenic differentiation of periosteal progenitors in fracture repair. Prx1Cre-targeted Cox-2 gene deletion in mesenchyme resulted in marked reduction of intramembraneous and endochondral bone repair, leading to accumulation of poorly differentiated mesenchyme and immature cartilage in periosteal callus. In contrast, Col2Cre-targeted Cox-2 gene deletion in cartilage resulted in a deficiency primarily in cartilage conversion into bone. Further cell culture analyses using Cox-2 deficient PDMPCs demonstrated reduced osteogenic differentiation in monolayer cultures, blocked chondrocyte differentiation and hypertrophy in high density micromass cultures. Gene expression microarray analyses demonstrated downregulation of a key set of genes associated with bone/cartilage formation and remodeling, namely Sox9, Runx2, Osx, MMP9, VDR and RANKL. Pathway analyses demonstrated dysregulation of the HIF-1, PI3K-AKT and Wnt pathways in Cox-2 deficient cells. Collectively, our data highlight a crucial role for Cox-2 from cells of mesenchymal lineages in modulating key pathways that control periosteal progenitor cell growth, differentiation, and angiogenesis in fracture repair.

Membrane phospholipids, EML4-ALK, and Hsp90 as novel targets in lung cancer treatment

Approximately one third of patients with non-small cell lung cancer have unresectable stage IIIA or stage IIIB disease; combined cytotoxic chemotherapy and radiation therapy delivered concurrently has been established as the standard treatment for such patients. Despite many clinical trials that tested several different radiochemotherapy combinations, it seems that a plateau of efficiencies at the acceptable risk of complications has been reached. Clinical studies indicate that the improved efficacy of radiochemotherapy is associated with the radiosensitizing effects of chemotherapy. Improvement of outcomes of this combined modality by developing novel radiosensitizers is a viable therapeutic strategy. In addition to causing cell death, ionizing radiation also induces a many-faceted signaling response, which activates numerous prosurvival pathways that lead to enhanced proliferation in the endothelial cells and increased vascularization in tumors. Radiation at doses used in the clinic activates cytoplasmic phospholipase A2, leading to increased production of arachidonic acid and lysophosphatidylcholine. The former is the initial step in the generation of eicosanoids, while the later is the initial step in the formation of lysophosphatidic acid, leading to the activation of inflammatory pathways. The echinoderm microtubule-associated protein-like 4 anaplastic lymphoma kinase (EML4-ALK) is member of the insulin superfamily of receptor tyrosine kinases. The EML4-ALK fusion gene appears unique to lung cancer and signals through extracellular signal regulated kinase and phosphoinositide 3-kinase. Heat shock protein 90 (Hsp90) is often overexpressed and present in an activated multichaperone complex in cancer cells, and it is now regarded as essential for malignant transformation and progression. In this review we focus on radiosensitizing strategies involving the targeting of membrane phospholipids, EML4-ALK, and Hsp90 with specific inhibitors and briefly discuss the combination of radiation with antivascular agents.

Inflammatory and microenvironmental factors involved in breast cancer progression

The primary reason for the high mortality rate of breast cancer is metastasis, which can result in a poor survival rate. The tumor environment is important for promotion and invasion of cancer cells. Recent studies have shown that inflammation is associated with breast cancer. Therefore, it is important to investigate the role of the inflammatory and microenvironment in breast cancer progression and metastasis. The present review summarizes some of the markers for inflammation and breast cancer invasion, which may aid in the design of an appropriate therapy for metastatic breast cancer. The following four inflammatory markers are discussed in this review: (1) Tumor associated macrophages (TAMs); (2) Matrix metalloproteinases (MMPs); (3) Sphingosine 1-phosphate (S1P); (4) C-reactive protein (CRP). TAMs are commonly found in breast cancer patients, and high infiltration is positively correlated with poor prognosis and low survival rate. MMPs are well-known for their roles in the degradation of ECM components when cancer cells invade and migrate. MMPs are also associated with inflammation through recruitment of a variety of stromal cells such as fibroblasts and leukocytes. S1P is an inflammatory lipid and is involved in various cellular processes such as proliferation, survival, and migration. Recent studies indicate that S1P participates in breast cancer invasion in various ways. CRP is used clinically to indicate the outcome of cancer patients as well as acute inflammatory status. This review summarizes the current understanding on the role of S1P in CRP expression which promotes the breast epithelial cell invasion, suggesting a specific mechanism linking inflammation and breast cancer. The present review might be useful for understanding the relationship between inflammation and breast cancer for the development of pharmacological interventions that may control the primary molecules involved in the breast cancer microenvironment.

MMP1, MMP9, and COX2 expressions in promonocytes are induced by breast cancer cells and correlate with collagen degradation, transformation-like morphological changes in MCF-10A acini, and tumor aggressiveness

Tumor-associated immune cells often lack immune effector activities, and instead they present protumoral functions. To understand how tumors promote this immunological switch, invasive and noninvasive breast cancer cell (BRC) lines were cocultured with a promonocytic cell line in a Matrigel-based 3D system. We hypothesized that if communication exists between tumor and immune cells, coculturing would result in augmented expression of genes associated with tumor malignancy. Upregulation of proteases MMP1 and MMP9 and inflammatory COX2 genes was found likely in response to soluble factors. Interestingly, changes were more apparent in promonocytes and correlated with the aggressiveness of the BRC line. Increased gene expression was confirmed by collagen degradation assays and immunocytochemistry of prostaglandin 2, a product of COX2 activity. Untransformed MCF-10A cells were then used as a sensor of soluble factors with transformation-like capabilities, finding that acini formed in the presence of supernatants of the highly aggressive BRC/promonocyte cocultures often exhibited total loss of the normal architecture. These data support that tumor cells can modify immune cell gene expression and tumor aggressiveness may importantly reside in this capacity. Modeling interactions in the tumor stroma will allow the identification of genes useful as cancer prognostic markers and therapy targets.

The Role of Mitogen-Activated Protein Kinase-Activated Protein Kinases (MAPKAPKs) in Inflammation

Mitogen-activated protein kinase (MAPK) pathways are implicated in several cellular processes including proliferation, differentiation, apoptosis, cell survival, cell motility, metabolism, stress response and inflammation. MAPK pathways transmit and convert a plethora of extracellular signals by three consecutive phosphorylation events involving a MAPK kinase kinase, a MAPK kinase, and a MAPK. In turn MAPKs phosphorylate substrates, including other protein kinases referred to as MAPK-activated protein kinases (MAPKAPKs). Eleven mammalian MAPKAPKs have been identified: ribosomal-S6-kinases (RSK1-4), mitogen- and stress-activated kinases (MSK1-2), MAPK-interacting kinases (MNK1-2), MAPKAPK-2 (MK2), MAPKAPK-3 (MK3), and MAPKAPK-5 (MK5). The role of these MAPKAPKs in inflammation will be reviewed.

Protumor activities of the immune response: insights in the mechanisms of immunological shift, oncotraining, and oncopromotion

Experimental and clinical studies indicate that cells of the innate and adaptive immune system have both anti- and pro-tumor activities. This dual role of the immune system has led to a conceptual shift in the role of the immune system's regulation of cancer, in which immune-tumor cell interactions are understood as a dynamic process that comprises at least five phases: immunosurveillance, immunoselection, immunoescape, oncotraining, and oncopromotion. The tumor microenvironment shifts immune cells to perform functions more in tune with the tumor needs (oncotraining); these functions are related to chronic inflammation and tissue remodeling activities. Among them are increased proliferation and survival, increased angiogenesis and vessel permeability, protease secretion, acquisition of migratory mesenchymal characteristics, and self-renewal properties that altogether promote tumor growth and metastasis (oncopromotion). Important populations in all these pro-tumor processes are M2 macrophages, N2 neutrophils, regulatory T cells, and myeloid derived suppressor cells; the main effectors molecules are CSF-1, IL-6, metalloproteases, VEGF, PGE-2, TGF- β , and IL-10. Cancer prognosis correlates with densities and concentrations of protumoral populations and molecules, providing ideal targets for the intelligent design of directed preventive or anticancer therapies.

Structure and ligand based drug design strategies in the development of novel 5- LOX inhibitors

Lipoxygenases (LOXs) are non-heme iron containing dioxygenases involved in the oxygenation of polyunsaturated fatty acids (PUFAs) such as arachidonic acid (AA). Depending on the position of insertion of oxygen, LOXs are classified into 5-, 8-, 9-, 12- and 15-LOX. Among these, 5-LOX is the most predominant isoform associated with the formation of 5-hydroperoxyeicosatetraenoic acid (5-HpETE), the precursor of non-peptido (LTB₄) and peptido (LTC₄, LTD₄, and LTE₄) leukotrienes. LTs are involved in inflammatory and allergic diseases like asthma, ulcerative colitis, rhinitis and also in cancer. Consequently 5-LOX has become target for the development of therapeutic molecules for treatment of various inflammatory disorders. Zileuton is one such inhibitor of 5-LOX approved for the treatment of asthma.

In the recent times, computer aided drug design (CADD) strategies have been applied successfully in drug development processes. A comprehensive review on structure based drug design strategies in the development of novel 5-LOX inhibitors is presented in this article. Since the crystal structure of 5-LOX has been recently solved, efforts to develop 5-LOX inhibitors have mostly relied on ligand based rational approaches. The present review provides a comprehensive survey on these strategies in the development of 5-LOX inhibitors.

Involvement of inflammatory factors in pancreatic carcinogenesis and preventive effects of anti-inflammatory agents

Chronic inflammation is known to be a risk for many cancers, including pancreatic cancer. Heavy alcohol drinking and cigarette smoking are major causes of pancreatitis, and epidemiological studies have shown that smoking and chronic pancreatitis are risk factors for pancreatic cancer. Meanwhile, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) are elevated in pancreatitis and pancreatic cancer tissues in humans and in animal models. Selective inhibitors of iNOS and COX-2 suppress pancreatic cancer development in a chemical carcinogenesis model of hamsters treated with N-nitrosobis(2-oxopropyl)amine (BOP). In addition, hyperlipidemia, obesity, and type II diabetes are also suggested to be associated with chronic inflammation in the pancreas and involved in pancreatic cancer development. We have shown that a high-fat diet increased pancreatic cancer development in BOP-treated hamsters, along with aggravation of hyperlipidemia, severe fatty infiltration, and increased expression of adipokines and inflammatory factors in the pancreas. Of note, fatty pancreas has been observed in obese and/or diabetic cases in humans. Preventive effects of anti-hyperlipidemic/anti-diabetic agents on pancreatic cancer have also been shown in humans and animals. Taking this evidence into consideration, modulation of inflammatory factors by anti-inflammatory agents will provide useful data for prevention of pancreatic cancer.