Sulindac sulfide, an aspirin-like compound, inhibits proliferation, causes cell cycle quiescence, and induces apoptosis in HT-29 colon adenocarcinoma cells

Synthesis of isothiocyanato alkyl sulfides from alkenes using KSCN and DMTSM

A method for the synthesis of isothiocyanato alkyl sulfides from KSCN and DMTSM under metal-free conditions has been developed. The features of this reaction are low-cost, readily accessible starting materials and the use of KSCN as nucleophiles for C-NCS bond formation. Alkenes with various substituted groups react smoothly and the desired products are obtained in moderate to good yields.

Robust, scalable construction of an electrophilic deuterated methylthiolating reagent: facile access to SCD3-containing scaffolds

We have established a practical and concise method for the straightforward access of a universal deuterated methylthiolating reagent through a one-pot gram-scale operation under mild conditions. This odourless electrophilic SCD₃ reagent was widely applied to react with numerous representative nucleophiles and approached various valuable SCD₃ analogues with excellent levels of deuterium content (>99% D). The divergent further transformations were smoothly carried out to obtain the significant derivatives with different oxidative states in high efficiency.

NSAIDs Naproxen, Ibuprofen, Salicylate, and Aspirin Inhibit TRPM7 Channels by Cytosolic Acidification

Non-steroidal anti-inflammatory drugs (NSAIDs) are used for relieving pain and inflammation accompanying numerous disease states. The primary therapeutic mechanism of these widely used drugs is the inhibition of cyclooxygenase 1 and 2 (COX1, 2) enzymes that catalyze the conversion of arachidonic acid into prostaglandins. At higher doses, NSAIDs are used for prevention of certain types of cancer and as experimental treatments for Alzheimer’s disease. In the immune system, various NSAIDs have been reported to influence neutrophil function and lymphocyte proliferation, and affect ion channels and cellular calcium homeostasis. Transient receptor potential melastatin 7 (TRPM7) cation channels are highly expressed in T lymphocytes and are inhibited by Mg²⁺, acidic pH, and polyamines. Here, we report a novel effect of naproxen, ibuprofen, salicylate, and acetylsalicylate on TRPM7. At concentrations of 3–30mM, they reversibly inhibited TRPM7 channel currents. By measuring intracellular pH with the ratiometric indicator BCECF, we found that at 300μM to 30mM, these NSAIDs reversibly acidified the cytoplasm in a concentration-dependent manner, and propose that TRPM7 channel inhibition is a consequence of cytosolic acidification, rather than direct. NSAID inhibition of TRPM7 channels was slow, voltage-independent, and displayed use-dependence, increasing in potency upon repeated drug applications. The extent of channel inhibition by salicylate strongly depended on cellular PI(4,5)P₂ levels, as revealed when this phospholipid was depleted with voltage-sensitive lipid phosphatase (VSP). Salicylate inhibited heterologously expressed wildtype TRPM7 channels but not the S1107R variant, which is insensitive to cytosolic pH, Mg²⁺, and PI(4,5)P₂ depletion. NSAID-induced acidification was also observed in Schneider 2 cells from Drosophila, an organism that lacks orthologous COX genes, suggesting that this effect is unrelated to COX enzyme activity. A 24-h exposure to 300μM–10mM naproxen resulted in a concentration-dependent reduction in cell viability. In addition to TRPM7, the described NSAID effect would be expected to apply to other ion channels and transporters sensitive to intracellular pH.

Pan-RAS inhibitors: Hitting multiple RAS isozymes with one stone

Mutations in the three RAS oncogenes are present in approximately 30% of all human cancers that drive tumor growth and metastasis by aberrant activation of RAS-mediated signaling. Despite the well-established role of RAS in tumorigenesis, past efforts to develop small molecule inhibitors have failed for various reasons leading many to consider RAS as "undruggable." Advances over the past decade with KRAS(G12C) mutation-specific inhibitors have culminated in the first FDA-approved RAS drug, sotorasib. However, the patient population that stands to benefit from KRAS(G12C) inhibitors is inherently limited to those patients harboring KRAS(G12C) mutations. Additionally, both intrinsic and acquired mechanisms of resistance have been reported that indicate allele-specificity may afford disadvantages. For example, the compensatory activation of uninhibited wild-type (WT) NRAS and HRAS isozymes can rescue cancer cells harboring KRAS(G12C) mutations from allele-specific inhibition or the occurrence of other mutations in KRAS. It is therefore prudent to consider alternative drug discovery strategies that may overcome these potential limitations. One such approach is pan-RAS inhibition, whereby all RAS isozymes co-expressed in the tumor cell population are targeted by a single inhibitor to block constitutively activated RAS regardless of the underlying mutation. This chapter provides a review of past and ongoing strategies to develop pan-RAS inhibitors in detail and seeks to outline the trajectory of this promising strategy of RAS inhibition.

Highly Regioselective Tandem Reaction of Ene-Yne-Oxazolones Induced by H-Phosphonates: Construction of Phosphinylindane Derivatives

A highly regioselective divergent approach for the phosphine-containing indane/indene derivatives from the ene-yne-oxazolone precursors was reported. An insight into the reaction mechanism involving the phospha-1,4-addition followed by 5-exo-dig ring closure with a concomitant C-P/C-C bond formation was also proposed. This promising protocol utilized H-phosphonate as the phosphonating reagent in a silver-catalyzed or base-mediated cascade cyclization to construct the corresponding phosphorylated spiroindenoxazolones and amidoindenes, respectively, in good yields (up to 88% yield).

Visible-Light-Promoted Cross-Coupling Reactions of Aryldiazonium Salts with S-Methyl-d3 Sulfonothioate or Se-Methyl-d3 Selenium Sulfonate: Synthesis of Trideuteromethylated Sulfides, Sulfoxides, and Selenides

A novel visible-light-photocatalytic deuterated thiomethylation/methylselenation of aryldiazonium salts utilizing S/Se-methyl-d₃ sulfonothioate has been developed. The mild conditions and the various functional groups provide a green protocol for the efficient and rapid introduction of the S-CD₃ or Se-CD₃ group with useful levels of deuterium content (>91% D). Trideuteromethyl sulfoxides have also been successfully chemoselectively observed by simple atmospheric changes under photocatalytic conditions.

NSAIDs-dependent adaption of the mitochondria-proteasome system in immortalized human cardiomyocytes

The progressive consumption growth of non-steroidal anti-inflammatory drugs (NSAIDs) has progressively raised the attention toward the gastrointestinal, renal, and cardiovascular toxicity. Increased risk of cardiovascular diseases was strictly associated with the usage of COX-2 selective NSAIDs. Other studies allowed to clarify that the cardiovascular risk is not limited to COX-2 selective but also extended to non-selective NSAIDs, such as Diclofenac and Ketoprofen. To date, although a less favorable cardiovascular risk profile for Diclofenac as compared to Ketoprofen is reported, the mechanisms through which NSAIDs cause adverse cardiovascular events are not entirely understood. The present study aimed to evaluate the effects of Ketoprofen in comparison with Diclofenac in immortalized human cardiomyocytes. The results obtained highlight the dose-dependent cardiotoxicity of Diclofenac compared to Ketoprofen. Despite both drugs induce the increase in ROS production, decrease of mitochondrial membrane potential, and proteasome activity modulation, only Diclofenac exposure shows a marked alteration of these intracellular parameters, leading to cell death. Noteworthy, Diclofenac decreases the proteasome 26S DC and this scenario may be dependent on the intracellular overload of oxidized proteins. The data support the hypothesis that immortalized human cardiomyocytes exposed to Ketoprofen are subjected to tolerable stress events, conversely Diclofenac exposition triggers cell death.

Progress in Drug and Formulation Development for the Chemoprevention of Oral Squamous Cell Carcinoma: A Review

BACKGROUND

Cancer is a life-threatening global problem with high incidence rates. Prioritizing the prevention of cancer, chemopreventive agents have drawn much attention from the researchers.

OBJECTIVE

This review focuses on the discussion of the progress in the development of chemopreventive agents and formulations related to the prevention of oral cancer.

METHODS

In this perspective, an extensive literature survey was carried out to understand the mechanism, control and chemoprevention of oral cancer. Different patented agents and formulations have also exhibited cancer preventive efficacy in experimental studies. This review summarizes the etiology of oral cancer and developments in prevention strategies.

RESULTS

The growth of oral cancer is a multistep activity necessitating the accumulation of genetic as well as epigenetic alterations in key regulatory genes. Many risk factors are associated with oral cancer. Genomic technique for sequencing all tumor specimens has been made available to help detect mutations. The recent development of molecular pathway and genetic tools has made the process of diagnosis easier, better forecast and efficient therapeutic management. Different chemical agents have been studied for their efficacy to prevent oral cancer and some of them have shown promising results.

CONCLUSION

Use of chemopreventive agents, either synthetic or natural origin, to prevent carcinogenesis is a worthy concept in the management of cancers. Preventive measures are helpful in controlling the occurrence or severity of the disease. The demonstrated results of preventive agents have opened an arena for the development of promising chemopreventive agents in the management of oral squamous cell carcinoma.

Aryl Methyl Sulfone Construction from Eco-Friendly Inorganic Sulfur Dioxide and Methyl Reagents

A three-component cross-coupling protocol of boronic acid, sodium metabisulfite, and dimethyl carbonate was developed for the construction of significant functional methyl sulfones, in which introduction of sulfur dioxide at the last stage was successfully achieved in one step. Inorganic sodium metabisulfite was used as an eco-friendly sulfur dioxide source. Green dimethyl carbonate was employed as methyl reagent in this transformation. Diverse functional methyl sulfones were obtained from various readily available boronic acids. Notably, the last-stage modification of pharmaceuticals and the synthesis of Firocoxib were efficiently established through this strategy.

Anti-inflammatory effects of Phytodolor® (STW 1) and components (poplar, ash and goldenrod) on human monocytes/macrophages

BACKGROUND

Populus tremula L. (Poplar), Fraxinus excelsior L. (ash) and Solidago virgaurea L. (goldenrod) have been used for medicinal purposes through centuries, to treat pain, fever and inflammation, but their mechanisms of action are still not fully understood. The present study was performed to investigate, whether the herbal medicinal product Phytodolor^® (STW 1) and its components have anti-inflammatory effects on activated human monocytes and differentiated human macrophages to elucidate their modes of action in comparison with well-known analgesic, non-steroidal anti-inflammatory drug (NSAIDs) as diclofenac.

METHODS

Adherent human monocytes obtained from peripheral blood mononuclear cells (PBMCs) were cultured in serum-free medium and pre-treated with 50-100 µg/ml of diclofenac, STW 1, their components, poplar, ash or goldenrod or its combination (0.05% to 2%). Thereafter, monocytes were activated with 0.1 or 1 µg/ml LPS for 24 h. The intracellular expressions of TNF-α or PTGS2 were determined by cell-based ELISA. Apoptotic cells were identified by YO-PRO-1 staining. Protein or total RNA were isolated to perform SDS-PAGE/Western blot and qRT-PCR analyses. PMA-differentiated human THP-1 macrophages were pre-treated with diclofenac (50 µg/ml) or STW1 (0.1%) and afterwards with LPS (1 µg/ml) and the translocation of the intracellular p62 NF-κB subunit was detected by immunofluorescence.

RESULTS

STW 1 inhibited the intracellular content of TNF-α and PTGS2 protein, as well as of TNF-α and PTGS2 gene expression and induced apoptosis in LPS-activated human monocytes under serum free conditions. Furthermore, STW 1 inhibited the translocation of the p65 subunit of the redox-regulated NF-κB into the nucleus in LPS-activated human macrophages.

CONCLUSION

The present in vitro investigations suggest a significant anti-inflammatory activity of STW 1 and its components by inhibiting pro-inflammatory cytokine as TNF-α and the key enzyme PTGS2 in LPS-activated human monocytes, which is, at least partly mediated through the suppression of NF-κB activation. Our results provide evidence for distinctive anti-inflammatory effects of STW 1 and its components on LPS-activated human monocytes/macrophages and, thus, for the therapeutic use of STW 1 in inflammation and pain related disorders.

Oxazole and thiazole analogs of sulindac for cancer prevention

Aim:

Experimental and epidemiological studies and clinical trials suggest that nonsteroidal anti-inflammatory drugs possess antitumor potential. Sulindac, a widely used nonsteroidal anti-inflammatory drug, can prevent adenomatous colorectal polyps and colon cancer, especially in patients with familial adenomatous polyposis. Sulindac sulfide amide (SSA) is an amide-linked sulindac sulfide analog that showed in vivo antitumor activity in a human colon tumor xenograft model.

Results/methodology:

A new analog series with heterocyclic rings such as oxazole or thiazole at the C-2 position of sulindac was prepared and screened against prostate, colon and breast cancer cell lines to probe the effect of these novel substitutions on the activity of sulindac analogs.

Conclusion:

In general, replacement of the amide function of SSA analogs had a negative impact on the cell lines tested. A small number of hits incorporating rigid oxazole or thiazole groups in the sulindac scaffold in place of the amide linkage show comparable activity to our lead agent SSA.

Amine Containing Analogs of Sulindac for Cancer Prevention

Background:

Sulindac belongs to the chemically diverse family of Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) that effectively prevent adenomatous colorectal polyps and colon cancer, especially in patients with familial adenomatous polyposis. Sulindac sulfide amide (SSA), an amide analog of sulindac sulfide, shows insignificant COX-related activity and toxicity while enhancing anticancer activity in vitro and demonstrating in vivo xenograft activity.

Objective:

Develop structure-activity relationships in the sulindac amine series and identify analogs with promising anticancer activities.

Method:

A series of sulindac amine analogs were designed and synthesized and then further modified in a “libraries from libraries” approach to produce amide, sulfonamide and N,N-disubstituted sulindac amine sub-libraries. All analogs were screened against three cancer cell lines (prostate, colon and breast).

Results:

Several active compounds were identified viain vitro cancer cell line screening with the most potent compound (26) in the nanomolar range.

Conclusion:

Compound 26 and analogs showing the most potent inhibitory activity may be considered for further design and optimization efforts as anticancer hit scaffolds.

Indomethacin elicits proteasomal dysfunctions develops apoptosis through mitochondrial abnormalities

Non-steroidal anti-inflammatory drugs (NSAIDs) are a class of drugs that are mainly used to treat pain, inflammation, and fever via cyclooxygenase-2 (COX-2) inhibition. There are abundant findings that uncover the hidden critical chemotherapeutics potential of NSAIDs in cancer treatment. However, still the precise mechanism by which NSAIDs could be used as an effective anti-tumor agent in the prevention of carcinogenesis is not well understood. Here, we show that indomethacin, a well-known NSAID, induces proteasomal dysfunction that results in accumulation of unwanted proteins, mitochondrial abnormalities, and successively stimulate apoptosis in cells. We observed the interaction of indomethacin with proteasome and noticed the massive accumulation of intracellular ubiquitin-positive proteins, which might be due to the suppression of proteasome activities. Furthermore, we also found that exposure of indomethacin causes the accumulation of critical proteasomal substrates that consequently generate severe mitochondrial abnormalities and prompt up key apoptotic events in cells. Our results demonstrate how indomethacin affects normal proteasomal functions and induces mitochondrial apoptosis in cells. These findings also improve our current understanding of how NSAIDs can exhibit crucial anti-proliferative effects in cells. In near future, our findings may suggest a new possible strategy for the development of specific proteasome inhibitors in conjunction with other chemo-preventive anticancer agents.

Effect of Sulindac Binary System on In Vitro and In Vivo Release Profiles: An Assessment of Polymer Type and Its Ratio

The bioavailability of sulindac (SDC), a nonsteroidal anti-inflammatory drug, is low due to poor aqueous solubility and poor dissolution rate. For this reason it is necessary to enhance the solubility and enhance dissolution of the drug by dispersing SDC in polyethylene glycols 6000 (PEG 6000) and polyvinyl pyrrolidone 40000 (PVP 40000) matrices using the coevaporation technique. Studying the influence of SDC to polymer ratio on drug content, percent yield, particle size, and in vitro release was performed. Differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy were used to characterize any change in crystal habit of SDC in the prepared formulae. The anti-inflammatory effect of SDC was studied using the hind paw edema model. It was found that incorporation of SDC in PEG 6000 and PVP 40000 matrices resulted in improving the dissolution rate, which was found to depend on the polymer and its weight ratio of the drug. It is clearly obvious that the dissolution rate was remarkably improved in drug PVP 40000 molecular dispersions when compared to drug PEG 6000 systems. Solid dispersion of SDC in PEG and PVP improved the anti-inflammatory effect of SDC and it was found that formula SDV5 exhibited a more pronounced inhibition of swelling than other formulae.

Repurposing Drugs in Oncology (ReDO)-diclofenac as an anti-cancer agent

Diclofenac (DCF) is a well-known and widely used non-steroidal anti-inflammatory drug (NSAID), with a range of actions which are of interest in an oncological context. While there has long been an interest in the use of NSAIDs in chemoprevention, there is now emerging evidence that such drugs may have activity in a treatment setting. DCF, which is a potent inhibitor of COX-2 and prostaglandin E2 synthesis, displays a range of effects on the immune system, the angiogenic cascade, chemo- and radio-sensitivity and tumour metabolism. Both pre-clinical and clinical evidence of these effects, in multiple cancer types, is assessed and summarised and relevant mechanisms of action outlined. Based on this evidence the case is made for further clinical investigation of the anticancer effects of DCF, particularly in combination with other agents - with a range of possible multi-drug and multi-modality combinations outlined in the supplementary materials accompanying the main paper.

Aspirin Suppresses the Growth and Metastasis of Osteosarcoma through the NF-κB Pathway

PURPOSE

Aspirin has recently been reported to reduce both the incidence and the risk of metastasis in colon cancer. However, there is no evidence at the cellular levels or in the animal models for such an effect of aspirin on cancer metastasis.

EXPERIMENTAL DESIGN

MTT assay, colony formation assay, and apoptosis assay were employed to analyze the effects of aspirin on the osteosarcoma cell viability in vitro. The NF-κB activity was measured by the NF-κB p65 luciferase reporter. Western blotting was used to analyze the proteins in cells. The migration and invasion abilities of osteosarcoma cells in vitro were measured by the Transwell assay. Xenograft-bearing mice were used to assess the roles of aspirin in both tumor growth and metastasis of osteosarcoma in vivo (n = 5-8 mice/group). An unpaired Student t test or ANOVA with the Bonferroni post hoc test were used for the statistical comparisons.

RESULTS

Aspirin reduced cell viability in a dose- and time-dependent manner in osteosarcoma cell lines, and aspirin synergistically sensitized osteosarcoma cells to cisplatin (DDP) in vitro and in vivo (P < 0.001). Moreover, aspirin markedly repressed the migration and invasion of osteosarcoma cells in vitro (P < 0.001), and dramatically diminished the occurrence of osteosarcoma xenograft metastases to the lungs in vivo (P < 0.001). Mechanistically, aspirin diminishes osteosarcoma migration, invasion, and metastasis through the NF-κB pathway.

CONCLUSIONS

Aspirin suppresses both the growth and metastasis of osteosarcoma through the NF-κB pathway at the cellular level and in the animal models.

In Vivo Antineoplastic Effects of the NSAID Sulindac in an Oral Carcinogenesis Model

The antineoplastic properties of the NSAID sulindac have long been studied. The purpose of this study was to explore sulindac's in vivo effects on oral squamous cell carcinoma (SCC) oncogenesis using the hamster cheek pouch oral carcinogenesis model (HOCM). Thirty Syrian golden hamsters were divided into three experimental and two control groups (n = 6 each). The animals' right buccal pouches were treated with carcinogen for 9 weeks in one experimental and one control group and for 14 weeks in all other three groups. The animals of two experimental groups received sulindac from the 1st week and those of the third experimental group from the 10th week. After the end of carcinogenesis, treated buccal pouches were removed and examined. In animals treated with carcinogen for 14 weeks, development of oral SCC and tumor volume were significantly lower in animals that received sulindac from the first week of the experiment. Oral SCC developing in animals that received sulindac were more frequently well differentiated compared with the control group. In animals treated with carcinogen for 9 weeks, the animals that received sulindac developed lower grade of epithelial dysplasia. Proliferation index Ki-67 and positivity for the antiapoptotic molecule survivin were lower in the animals that received sulindac. Treatment with sulindac appears to delays the progression of oral premalignant lesions to oral SCC in the HOCM, also resulting in smaller and better differentiated tumors. These in vivo antineoplastic effects may be related to sulindac's ability to decrease cell proliferation and to prevent survivin expression.

Molecular structure studies of (1S,2S)-2-benzyl-2,3-dihydro-2-(1H-inden-2-yl)-1H-inden-1-ol

The single enantiomer (1S,2S)-2-benzyl-2,3-dihydro-2-(1H-inden-2-yl)-1H-inden-1-ol (2), has recently been synthesized and isolated from its corresponding diastereoisomer (1). The molecular and crystal structures of this novel compound have been fully analyzed. The relative and absolute configurations have been determined by using a combination of analytical tools including X-ray crystallography, X-ray Powder Diffraction (XRPD) analysis and Nuclear Magnetic Resonance (NMR) spectroscopy.

Aspirin delimits platelet life span by proteasomal inhibition

Aspirin is widely used in clinical settings as an anti-inflammatory and anti-platelet drug due its inhibitory effect on cyclooxygenase activity. Although the drug has long been considered to be an effective and safe therapeutic regime against inflammatory and cardiovascular disorders, consequences of its cyclooxygenase-independent attributes on platelets, the key players in thrombogenesis, beg serious investigation. In this report we explored the effect of aspirin on platelet lifespan in murine model and its possible cytotoxicity against human platelets in vitro. Aspirin administration in mice led to significant reduction in half-life of circulating platelets, indicative of enhanced rate of platelet clearance. Aspirin-treated human platelets were found to be phagocytosed more efficiently by macrophages, associated with attenuation in platelet proteasomal activity and upregulation of conformationally active Bax, which were consistent with enhanced platelet apoptosis. Although the dosage of aspirin administered in mice was higher than the therapeutic regimen against cardiovascular events, it is comparable with the recommended anti-inflammatory prescription. Thus, above observations provide cautionary framework to critically re-evaluate prophylactic and therapeutic dosage regime of aspirin in systemic inflammatory as well as cardiovascular ailments.

Ibuprofen enhances the anticancer activity of cisplatin in lung cancer cells by inhibiting the heat shock protein 70

Hsp70 is often overexpressed in cancer cells, and the selective cellular survival advantage that it confers may contribute to the process of tumour formation. Thus, the pharmacological manipulation of Hsp70 levels in cancer cells may be an effective means of preventing the progression of tumours. We found that the downregulation of Hsp70 by ibuprofen in vitro enhances the antitumoural activity of cisplatin in lung cancer. Ibuprofen prominently suppressed the expression of Hsp70 in A549 cells derived from lung adenocarcinoma and sensitized them to cisplatin in association with an increase in the mitochondrial apoptotic cascade, whereas ibuprofen alone did not induce cell death. The cisplatin-dependent events occurring up- and downstream of mitochondrial disruption were accelerated by treatment with ibuprofen. The increase in cisplatin-induced apoptosis caused by the depletion of Hsp70 by RNA interference is evidence that the increased apoptosis by ibuprofen is mediated by its effect on Hsp70. Our observations indicate that the suppression of Hsp70 by ibuprofen mediates the sensitivity to cisplatin by enhancing apoptosis at several stages of the mitochondrial cascade. Ibuprofen, therefore, is a potential therapeutic agent that might allow lowering the doses of cisplatin and limiting the many challenge associated with its toxicity and development of drug resistance.

CDK/CCN and CDKI alterations for cancer prognosis and therapeutic predictivity

The regulation of cell growth and division occurs in an accurate sequential manner. It is dictated by the accumulation of cyclins (CCNs) and cyclin-dependent kinases (CDKs) complexes and degradation of CCNs. In human tumors, instead, the cell cycle is deregulated, causing absence of differentiation and aberrant cell growth. Oncogenic alterations of CCNs, CDKs, and CDKIs have been reported in more than 90% of human cancers, and the most frequent are those related to the G1 phase. Several molecular mechanisms, including gene overexpression, chromosomal translocations, point mutations, insertions and deletions, missense and frame shift mutation, splicing, or methylation, may be responsible for these alterations. The cell cycle regulators are involved in tumor progression given their association with cancers characterized by higher incidence of relapses and chemotherapy resistance. In the last decade anticancer drug researches focused on new compounds, able to target molecules related to changes in genes associated with tumor status. Recently, the studies have focused on the restoration of cell cycle control modulating molecular targets involved in cancer-cell alterations. This paper aims to correlate alterations of cell cycle regulators with human cancers and therapeutic responsivity.

NSAIDs inhibit tumorigenesis, but how?

Numerous epidemiologic studies have reported that the long-term use of nonsteroidal anti-inflammatory drugs (NSAID) is associated with a significant decrease in cancer incidence and delayed progression of malignant disease. The use of NSAIDs has also been linked with reduced risk from cancer-related mortality and distant metastasis. Certain prescription-strength NSAIDs, such as sulindac, have been shown to cause regression of precancerous lesions. Unfortunately, the extended use of NSAIDs for chemoprevention results in potentially fatal side effects related to their COX-inhibitory activity and suppression of prostaglandin synthesis. Although the basis for the tumor growth-inhibitory activity of NSAIDs likely involves multiple effects on tumor cells and their microenvironment, numerous investigators have concluded that the underlying mechanism is not completely explained by COX inhibition. It may therefore be possible to develop safer and more efficacious drugs by targeting such COX-independent mechanisms. NSAID derivatives or metabolites that lack COX-inhibitory activity, but retain or have improved anticancer activity, support this possibility. Experimental studies suggest that apoptosis induction and suppression of β-catenin-dependent transcription are important aspects of their antineoplastic activity. Studies show that the latter involves phosphodiesterase inhibition and the elevation of intracellular cyclic GMP levels. Here, we review the evidence for COX-independent mechanisms and discuss progress toward identifying alternative targets and developing NSAID derivatives that lack COX-inhibitory activity but have improved antineoplastic properties.

Acetyl salicylic acid locally enhances functional recovery after sciatic nerve transection in rat

Local effect of acetyl salicylic acid (ASA) on peripheral nerve regeneration was studied using a rat sciatic nerve transection model. Forty-five male healthy White Wistar rats were divided into three experimental groups (n = 15), randomly: Sham-operation (SHAM), control (SIL), and ASA-treated (SIL/ASA) groups. In SHAM group after anesthesia left sciatic nerve was exposed through a gluteal muscle incision and after homeostasis the muscle was sutured. In SIL group the left sciatic nerve was exposed the same way and transected proximal to tibio-peroneal bifurcation leaving a 10-mm gap. Proximal and distal stumps were each inserted into a silicone tube and filled with 10 μl phosphate buffered solution. In SIL/ASA group defect was bridged using a silicone tube filled with 10 μl acetyl salisylic acid (0.1 mg/ml). Each group was subdivided into three subgroups of five animals each and were studied 4, 8, and 12 weeks after surgery. Data were analyzed statistically by factorial analysis of variance (ANOVA) and the Bonferroni test for pair-wise comparisons. Functional study confirmed faster and better recovery of regenerated axons in SIL/ASA than in SIL group (p < 0.05). Gastrocnemius muscle mass in SIL/ASA was significantly more than in SIL group. Morphometric indices of regenerated fibers showed that the number and diameter of the myelinated fibers in SIL/ASA were significantly higher than in control group. In immuohistochemistry, location of reactions to S-100 in SIL/ASA was clearly more positive than in SIL group. Response to local treatment of ASA demonstrates that it influences and improves functional recovery of peripheral nerve regeneration.

The proapoptotic effect of traditional and novel nonsteroidal anti-inflammatory drugs in mammalian and yeast cells

Nonsteroidal anti-inflammatory drugs (NSAIDs) have long been used to treat pain, fever, and inflammation. However, mounting evidence shows that NSAIDs, such as aspirin, have very promising antineoplastic properties. The chemopreventive, antiproliferative behaviour of NSAIDs has been associated with both their inactivation of cyclooxygenases (COX) and their ability to induce apoptosis via pathways that are largely COX-independent. In this review, the various proapoptotic pathways induced by traditional and novel NSAIDs such as phospho-NSAIDs, hydrogen sulfide-releasing NSAIDs and nitric oxide-releasing NSAIDs in mammalian cell lines are discussed, as well as the proapoptotic effects of NSAIDs on budding yeast which retains the hallmarks of mammalian apoptosis. The significance of these mechanisms in terms of the role of NSAIDs in effective cancer prevention is considered.

COX-Independent Mechanisms of Cancer Chemoprevention by Anti-Inflammatory Drugs

Epidemiological and clinical studies suggest that non-steroidal anti-inflammatory drugs (NSAIDs), including cyclooxygenase (COX)-2 selective inhibitors, reduce the risk of developing cancer. Experimental studies in human cancer cell lines and rodent models of carcinogenesis support these observations by providing strong evidence for the antineoplastic properties of NSAIDs. The involvement of COX-2 in tumorigenesis and its overexpression in various cancer tissues suggest that inhibition of COX-2 is responsible for the chemopreventive efficacy of these agents. However, the precise mechanisms by which NSAIDs exert their antiproliferative effects are still a matter of debate. Numerous other studies have shown that NSAIDs can act through COX-independent mechanisms. This review provides a detailed description of the major COX-independent molecular targets of NSAIDs and discusses how these targets may be involved in their anticancer effects. Toxicities resulting from COX inhibition and the suppression of prostaglandin synthesis preclude the long-term use of NSAIDs for cancer chemoprevention. Furthermore, chemopreventive efficacy is incomplete and treatment often leads to the development of resistance. Identification of alternative NSAID targets and elucidation of the biochemical processes by which they inhibit tumor growth could lead to the development of safer and more efficacious drugs for cancer chemoprevention.

Mechanisms of the anti-proliferative and anti-inflammatory effects of the herbal fixed combination STW 5 (Iberogast®) on colon adenocarcinoma (HT29) cells in vitro

INTRODUCTION

Several conventional pharmaceuticals like non-steroidal anti-inflammatory drugs (NSAIDS) or selective cyclooxygenase-2 (COX-2) inhibitors have been demonstrated to exert anti-proliferative effects and to induce apoptosis in a variety of cell lines, e.g. colon, stomach, or prostate cancer cells. STW 5 (Iberogast(®)), a combination of nine plant extracts, is widely used in the treatment of gastrointestinal disorders, including functional dyspepsia and irritable bowel syndrome for which the involvement of an inflammatory etiology is discussed. To investigate the possible anti-proliferative effects, STW 5 and its components have been tested by using the colon-carcinoma cell line HT-29. The analyses have been performed in comparison to acetylsalicylic acid (ASA) and diclofenac (Diclo), which are well-known to reduce colon carcinoma risk.

RESULTS

STW 5 showed significant anti-proliferative and pro-apoptotic effects on HT-29 cancer cells, similar to NSAIDs under test. However, using the LDH assay, STW 5 revealed significantly lower cytotoxicity than Diclo at same concentrations. In contrast to NSAIDs, STW 5 induced COX-1/COX-2, caspase-3 and Bax mRNA expressions in HT-29 and blocked LPS mediated translocation of the NF-κB p65 from the cytoplasm into the nucleus in PMA-differentiated THP-1 macrophages. These effects might be relevant, e.g. for prevention of undesirable side effects like gastric erosions.

CONCLUSION

Our data suggest that the pro-apoptotic effect of STW 5 on HT-29 cells is involving multiple targets and is possibly due to an activation of the caspase cascade via mitochondrial destabilization. Active concentrations of STW 5 are, in relation to therapeutic doses, comparable to those of ASA and Diclo, suggesting a similar favorable effect on colon carcinoma risk.

Synergistic induction of apoptosis by sulindac and simvastatin in A549 human lung cancer cells via reactive oxygen species-dependent mitochondrial dysfunction

Prevention of lung cancer is more feasible and holds greater promise when different agents are used in combination to target multiple processes during carcinogenesis. The mechanisms by which non-steroidal anti-inflammatory drugs and statins inhibit cancer cell growth and induce apoptosis are not fully understood. This study was designed to investigate lung cancer chemoprevention through a mechanism-based approach using sulindac at low doses in combination with simvastatin. We found that sulindac-induced cytotoxicity was significantly enhanced in the presence of simvastatin. The combination of sulindac and simvastatin induced more extensive caspase-dependent apoptosis in A549 cells compared to that induced with either drug alone. The combination of sulindac and simvastatin also increased the loss of mitochondrial transmembrane potential (∆Ψm) and the cytosolic release of cytochrome c. In addition, ROS generation in cells treated with both sulindac and simvastatin was markedly increased compared to cells treated with either sulindac or simvastatin alone. The enhancement of ROS generation by sulindac and simvastatin was abrogated by pretreatment with NAC, which also prevented apoptosis and mitochondrial dysfunction induced by sulindac and simvastatin. These results suggest that sulindac and simvastatin-induced ROS generation in A549 lung cancer cells causes their accumulation in mitochondria, triggering the release of apoptogenic molecules from the mitochondria to the cytosol, and thus leading to caspase activation and cell death.

Implication of eIF2α kinase GCN2 in induction of apoptosis and endoplasmic reticulum stress-responsive genes by sodium salicylate

OBJECTIVES

Sodium salicylate (NaSal) can disturb cell viability by affecting the activity of multiple cellular molecules. In this work, we investigated the involvement of stress-responsive kinase GCN2 in regulating cell death and expression of stress genes in mouse embryonic fibroblasts (MEFs) upon exposure to NaSal.

METHODS

Cell viability was assayed using the 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) method, and apoptosis was evaluated by annexin V and propidium iodide staining. A polymerase chain reaction (PCR) array approach was used to analyse differential expression of a panel of 84 endoplasmic reticulum (ER) stress-associated genes. Gene reporter assays were carried out to determine activity of ER stress element (ERSE), and the protein levels of activating transcription factor 6 (ATF6) and C/EBP homologous protein (CHOP) were determined by western blot.

KEY FINDINGS

NaSal treatment resulted in reduction of cellular viability and induction of apoptosis in wild-type but not Gcn2(-/-) cells. Many genes with important functions in protein synthesis/degradation, transcriptional regulation and apoptosis were induced by NaSal and most of these were dependent on GCN2. The activation of ERSE within Ddit3 and the production of CHOP and ATF6 induced by NaSal required GCN2.

CONCLUSIONS

Our data provide evidence for the involvement of GCN2 in apoptosis and gene expression triggered by NaSal, and contributes to the understanding of molecular events occurring in NaSal-treated cells.

Utilizing endoscopic technology to reveal real-time proteomic alterations in response to chemoprevention

Cancer chemoprevention approaches use either pharmacological or dietary agents to impede, arrest or reverse the carcinogenic process. Although several agents have shown effectiveness against colon cancer, present intervention strategies provide only partial reduction. In this study, we utilized high-resolution endoscopy to obtain colon tumor biopsy specimens from Apc mutant mice before and after 2-wk sulindac intervention. To acquire information beyond genomics, proteome analysis using the ProteomeLab PF2D platform was implemented to generate 2-D protein expression maps from biopsies. Chromatograms produced common signature profiles between sulindac and nonsulindac treated samples, and contrasting profiles termed "fingerprints". We selected a double peak that appeared in tumor biopsies from sulindac-treated mice. Further analyses using MS sequencing identified this protein as histone H2B. The location of H2B in the 1(st) dimension strongly suggested PTM, consistent with identification of two oxidized methionines. While further studies on sulindac proteomic fingerprints are underway, this study demonstrates the feasibility and advantages of "real-time" proteomic analysis for obtaining information on biomarker discovery and drug activity that would not be revealed by a genetic assay. This approach should be broadly applicable for assessing lesion responsiveness in a wide range of translational and human clinical studies.

(1S)-1-Phenylethanaminium 4-{[(1S,2S)-1-hydroxy-2,3-dihydro-1H,1'H-[2,2'-biinden]-2-yl]methyl}benzoate

The title molecular salt, C(8)H(12)N(+)·C(26)H(21)O(3)(-), contains a dimeric indane pharmacophore that demonstrates potent anti-inflammatory activity. The indane group of the anion exhibits some disorder about the α-C atom, which appears common to many structures containing this group. A model to account for the slight disorder was attempted, but this was deemed unsuccessful because applying bond-length constraints to all the bonds about the α-C atom led to instability in the refinement. The absolute configuration was determined crystallographically as S,S,S by anomalous dispersion methods with reference to both the Flack parameter and Bayesian statistics on Bijvoet differences. The configuration was also determined by an a priori knowledge of the absolute configuration of the (1S)-1-phenylethanaminium counter-ion. The molecules pack in the crystal structure to form an infinite two-dimensional hydrogen-bond network in the (100) plane of the unit cell.

6-(methylamino)hexane-1,2,3,4,5-pentanol 4-(((1S,2S)-1-hydroxy-2,3-dihydro-1H,1'H-[2,2-biinden]-2-yl)methyl)benzoate (PH46A): a novel small molecule with efficacy in murine models of colitis

The indane skeleton is found naturally and in several therapeutic molecules in medicinal chemistry. During our work on the anti-inflammatory activity of naturally occurring and synthetic indanes, we have synthesized a novel indane scaffold that has been optimized for both anti-inflammatory activity and bioavailability. We have evaluated our lead molecule, PH46A, in in vivo models of inflammatory bowel disease (IBD), an area of considerable unmet clinical need; current therapies are often unable to control the course of the disease. The compound significantly reduced histological damage and serum amyloid A (SAA) levels in IL-10(-/-) colitis mice, was efficacious in the 5% dextran sulfate sodium (DSS) colitis model, and compared favorably with prednisolone in this model and supports its potential use to treat acute exacerbations of the disease. Further, the graded response to the compound may also lend itself to be used at a lower dose to maintain periods of remission.

Investigation of nuclear nano-morphology marker as a biomarker for cancer risk assessment using a mouse model

The development of accurate and clinically applicable tools to assess cancer risk is essential to define candidates to undergo screening for early-stage cancers at a curable stage or provide a novel method to monitor chemoprevention treatments. With the use of our recently developed optical technology--spatial-domain low-coherence quantitative phase microscopy (SL-QPM), we have derived a novel optical biomarker characterized by structure-derived optical path length (OPL) properties from the cell nucleus on the standard histology and cytology specimens, which quantifies the nano-structural alterations within the cell nucleus at the nanoscale sensitivity, referred to as nano-morphology marker. The aim of this study is to evaluate the feasibility of the nuclear nano-morphology marker from histologically normal cells, extracted directly from the standard histology specimens, to detect early-stage carcinogenesis, assess cancer risk, and monitor the effect of chemopreventive treatment. We used a well-established mouse model of spontaneous carcinogenesis--Apc(Min) mice, which develop multiple intestinal adenomas (Min) due to a germline mutation in the adenomatous polyposis coli (Apc) gene. We found that the nuclear nano-morphology marker quantified by OPL detects the development of carcinogenesis from histologically normal intestinal epithelial cells, even at an early pre-adenomatous stage (six weeks). It also exhibits a good temporal correlation with the small intestine that parallels the development of carcinogenesis and cancer risk. To further assess its ability to monitor the efficacy of chemopreventive agents, we used an established chemopreventive agent, sulindac. The nuclear nano-morphology marker is reversed toward normal after a prolonged treatment. Therefore, our proof-of-concept study establishes the feasibility of the SL-QPM derived nuclear nano-morphology marker OPL as a promising, simple and clinically applicable biomarker for cancer risk assessment and evaluation of chemopreventive treatment.

The metabolism and pharmacokinetics of phospho-sulindac (OXT-328) and the effect of difluoromethylornithine

BACKGROUND AND PURPOSE

Phospho-sulindac (PS; OXT-328) prevents colon cancer in mice, especially when combined with difluoromethylornithine (DFMO). Here, we explored its metabolism and pharmacokinetics.

EXPERIMENTAL APPROACH

PS metabolism was studied in cultured cells, liver microsomes and cytosol, intestinal microsomes and in mice. Pharmacokinetics and biodistribution of PS were studied in mice.

KEY RESULTS

PS undergoes reduction and oxidation yielding PS sulphide and PS sulphone; is hydrolysed releasing sulindac, which generates sulindac sulphide (SSide) and sulindac sulphone (SSone), all of which are glucuronidated. Liver and intestinal microsomes metabolized PS extensively but cultured cells converted only 10% of it to PS sulphide and PS sulphone. In mice, oral PS is rapidly absorbed, metabolized and distributed to the blood and other tissues. PS survives only partially intact in blood; of its three major metabolites (sulindac, SSide and SSone), sulindac has the highest C(max) and SSone the highest t(1/2) ; their AUC(0-24h) are similar. Compared with conventional sulindac, PS generated more SSone but less SSide, which may contribute to the safety of PS. In the gastroduodenal wall of mice, 71% of PS was intact; sulindac, SSide and SSone together accounted for <30% of the total. This finding may explain the lack of gastrointestinal toxicity by PS. DFMO had no effect on PS metabolism but significantly reduced drug level in mouse plasma and other tissues.

CONCLUSIONS AND IMPLICATIONS

Our findings establish the metabolism of PS define its pharmacokinetics and biodistribution, describe its interactions with DFMO and largely explain its gastrointestinal safety.

Non-canonical Notch signaling: emerging role and mechanism

Notch is an ancient transmembrane receptor with crucial roles in cell-fate choices. Although the 'canonical' Notch pathway and its core members are well established - involving ligand-induced cleavage of Notch for transcriptional regulation - it has been unclear whether Notch can also function independently of ligand and transcription ('non-canonically') through a common mechanism. Recent studies suggest that Notch can non-canonically exert its biological functions by post-translationally targeting Wnt/β-catenin signaling, an important cellular and developmental regulator. The non-canonical Notch pathway appears to be highly conserved from flies to mammals. Here, we discuss the emerging conserved mechanism and role of ligand/transcription-independent Notch signaling in cell and developmental biology.

Piroxicam and C-phycocyanin mediated apoptosis in 1,2-dimethylhydrazine dihydrochloride induced colon carcinogenesis: exploring the mitochondrial pathway

Apoptosis is a synchronized procedure of cell death that is regulated by caspases and proapoptotic proteins. During apoptosis, translocation of cytochrome c, an electron carrier, from mitochondria into the cytosol is regulated by Bcl-2 family members. Cytochrome c in association with an apoptotic protease activating factor (Apaf), a proapoptotic protein essential for cell differentiation and procaspase-9 form the apoptosome complex, which consecutively activates effector caspase, caspase-3, and coordinate the implementation of apoptosis. In the current study, an attempt has been made to gain insight into piroxicam, a traditional nonsteroidal antiinflammatory drug and c-phycocyanin, a biliprotein from Spirulina platensis (cyanobacterium) mediated apoptosis in DMH-induced colon cancer. Male Sprague-Dawley rats were segregated into 5 groups: control, DMH, DMH + piroxicam, DMH + c-phycocyanin, and DMH + piroxicam + c-phycocyanin. Results illustrated that piroxicam and c-phycocyanin treatments stimulate cytochrome c release by downregulating the Bcl-2 (an antiapoptotic protein) expression significantly, while promoting the level of Bax (a proapoptotic protein), thereby activating caspases (caspases-9 and -3) and Apaf-1. The outcomes of the present study clearly signify that piroxicam and c-phycocyanin may mediate mitochondrial-dependent apoptosis in DMH-induced colon cancer. Moreover, apoptosis induction was more apparent in the combination regimen of piroxicam and c-phycocyanin than the individual drugs alone.