Demonstrating drug treatment efficacies by monitoring superoxide dynamics in human lung cancer cells with time-lapse fluorescence microscopy

Metformin hydrochloride, an antihyperglycemic agent, and sulindac, a nonsteroidal anti-inflammatory drug, are FDA-approved drugs known to exert anticancer effects. Previous studies demonstrated sulindac and metformin's anticancer properties through mitochondrial dysfunction and inhibition of mitochondrial electron transport chain complex I and key signaling pathways. In this study, various drugs were administered to A549 lung cancer cells, and results revealed that a combination of sulindac and metformin enhanced cell death compared to the administration of the drugs separately. To measure superoxide production over time, we employed a time-lapse fluorescence imaging technique using mitochondrial-targeted hydroethidine. Fluorescence microscopy data showed the most significant increases in superoxide production in the combination treatment of metformin and sulindac. Results showed significant differences between the combined drug treatment and control groups and between the positive control and control groups. This approach can be utilized to quantify the anticancer efficacy of drugs, creating possibilities for additional therapeutic options.

Effect of Solubility Improvement via Formation of an Amorphous Composite of Indomethacin and Sulindac on Membrane Permeability

The importance of permeability as well as solubility of the drug has been recognized in improving the solubility of poorly water-soluble drugs. This study investigated the impact of amorphous composites of indomethacin (IMC) and sulindac (SLD) on the membrane permeability of drugs. The IMC/SLD (1/1) formulation prepared by dry grinding was amorphous with a single glass transition temperature. The Fourier transform IR spectra and Raman spectra revealed formation of hydrogen bonds between the OH group of IMC and the carbonyl group of SLD. These results suggest that an amorphous composite was formed between IMC and SLD through hydrogen bonding. The amount of dissolved IMC and SLD from the amorphous composite of IMC/SLD (1/1) was higher than that of the untreated IMC or SLD in the dissolution test. The permeated amounts and permeation rates of both drugs were enhanced by increasing the solubility of the amorphous composite. Conversely, the apparent membrane permeability coefficients (P_app) were almost same for untreated drugs and amorphous composites. In the case of hydroxypropyl-β-cyclodextrin and sodium dodecyl sulfate, P_app of the drugs decreased with the addition of these compounds, although the drug solubility was enhanced by the solubilization effect. This study revealed that an amorphous composite formed through hydrogen bonding is an attractive pharmaceutical way to enhance the permeated amount and permeation rate without changing the P_app of both the drugs.

An anticoagulant/procoagulant self-converting and bleeding site targeting systemic nanotherapy for rapid controlling of non-compressible bleeding without risk of thrombosis

BACKGROUND

Hemorrhage, in particular noncompressible hemorrhage, is the leading cause of casualties in combat trauma and civilian trauma. Although systemic agents can staunch bleeding at both inaccessible and accessible injury sites, the application of systemic hemostats in clinics is still strictly limited by the nontargeting ability of hemostats and their subsequent potential for thromboembolic complications.

OBJECTIVE

To engineer an anticoagulant/procoagulant self-converting and bleeding site-targeting systemic nanohemostat for rapid controlling of non-compressible bleeding without risk of thrombosis.

METHOD

A multiscale computer simulation was taken to guide the self-assembly of sulindac (a prodrug of the anti-platelets agent, SUL) and poly-L-lysine (a cation polymer with platelets activation ability, PLL) for forming PLL/SUL nanoparticles (PSNs). In vitro platelets adhering ability, platelets activation effect, and hemostasis activity of PSNs were evaluated. Then, the biosafety, level of thrombosis, targeting ability, and hemostasis effect of systemic applied PSNs was carefully evaluated in various hemorrhage models.

RESULTS

PSNs were successfully prepared and showed good platelet adhesion and activation in vitro. Bleeding site targeting ability and hemostatic efficiency in different bleeding models were leveled up by PSNs markedly compare to vitamin K and etamsylate in vivo. SUL in PSNs could be metabolized into sulindac sulfide at clot sites in 4 hours for antiplatelet aggregation, thus reducing thrombotic risk compare to other hemostatic agents, via the ingenious utilization of prodrug metabolism in terms of time intervals and the adhesion on platelets.

CONCLUSIONS

PSNs is expected to be a low-cost, safe, efficient, clinically translatable first-aid hemostat for first-aid scenarios.

Novel Non-Cyclooxygenase Inhibitory Derivative of Sulindac Inhibits Breast Cancer Cell Growth In Vitro and Reduces Mammary Tumorigenesis in Rats

The nonsteroidal anti-inflammatory drug (NSAID) sulindac demonstrates attractive anticancer activity, but the toxicity resulting from cyclooxygenase (COX) inhibition and the suppression of physiologically important prostaglandins precludes its long-term, high dose use in the clinic for cancer prevention or treatment. While inflammation is a known tumorigenic driver, evidence suggests that sulindac's antineoplastic activity is partially or fully independent of its COX inhibitory activity. One COX-independent target proposed for sulindac is cyclic guanosine monophosphate phosphodiesterase (cGMP PDE) isozymes. Sulindac metabolites, i.e., sulfide and sulfone, inhibit cGMP PDE enzymatic activity at concentrations comparable with those associated with cancer cell growth inhibitory activity. Additionally, the cGMP PDE isozymes PDE5 and PDE10 are overexpressed during the early stages of carcinogenesis and appear essential for cancer cell proliferation and survival based on gene silencing experiments. Here, we describe a novel amide derivative of sulindac, sulindac sulfide amide (SSA), which was rationally designed to eliminate COX-inhibitory activity while enhancing cGMP PDE inhibitory activity. SSA was 68-fold and 10-fold less potent than sulindac sulfide (SS) in inhibiting COX-1 and COX-2, respectively, but 10-fold more potent in inhibiting growth and inducing apoptosis in breast cancer cells. The pro-apoptotic activity of SSA was associated with inhibition of cGMP PDE activity, elevation of intracellular cGMP levels, and activation of cGMP-dependent protein kinase (PKG) signaling, as well as the inhibition of β-catenin/Tcf transcriptional activity. SSA displayed promising in vivo anticancer activity, resulting in a 57% reduction in the incidence and a 62% reduction in the multiplicity of tumors in the N-methyl-N-nitrosourea (MNU)-induced model of breast carcinogenesis. These findings provide strong evidence for cGMP/PKG signaling as a target for breast cancer prevention or treatment and the COX-independent anticancer properties of sulindac. Furthermore, this study validates the approach of optimizing off-target effects by reducing the COX-inhibitory activity of sulindac for future targeted drug discovery efforts to enhance both safety and efficacy.

Weight Loss and/or Sulindac Mitigate Obesity-associated Transcriptome, Microbiome, and Protumor Effects in a Murine Model of Colon Cancer

Obesity is associated with an increased risk of colon cancer. Our current study examines whether weight loss and/or treatment with the NSAID sulindac suppresses the protumor effects of obesity in a mouse model of colon cancer. Azoxymethane-treated male FVB/N mice were fed a low-fat diet (LFD) or high-fat diet (HFD) for 15 weeks, then HFD mice were randomized to remain on HFD (obese) or switch to LFD [formerly obese (FOb-LFD)]. Within the control (LFD), obese, and FOb-LFD groups, half the mice started sulindac treatment (140 ppm in the diet). All mice were euthanized 7 weeks later. FOb-LFD mice had intermediate body weight levels, lower than obese but higher than control (P < 0.05). Sulindac did not affect body weight. Obese mice had greater tumor multiplicity and burden than all other groups (P < 0.05). Transcriptomic profiling indicated that weight loss and sulindac each modulate the expression of tumor genes related to invasion and may promote a more antitumor immune landscape. Furthermore, the fecal microbes Coprobacillus, Prevotella, and Akkermansia muciniphila were positively correlated with tumor multiplicity and reduced by sulindac in obese mice. Coprobacillus abundance was also decreased in FOb-LFD mice. In sum, weight loss and sulindac treatment, alone and in combination, reversed the effects of chronic obesity on colon tumor multiplicity and burden. Our findings suggest that an investigation regarding the effects of NSAID treatment on colon cancer risk and/or progression in obese individuals is warranted, particularly for those unable to achieve moderate weight loss.

PREVENTION RELEVANCE

Obesity is a colon cancer risk and/or progression factor, but the underlying mechanisms are incompletely understood. Herein we demonstrate that obesity enhances murine colon carcinogenesis and expression of numerous tumoral procancer and immunosuppressive pathways. Moreover, we establish that weight loss via LFD and/or the NSAID sulindac mitigate procancer effects of obesity.

Usefulness of Optimized Human Fecal Material in Simulating the Bacterial Degradation of Sulindac and Sulfinpyrazone in the Lower Intestine

The first aim of this study was to evaluate the usefulness of optimized human fecal material in simulating sulforeductase activity in the lower intestine by assessing bacterial degradation of sulindac and sulfinpyrazone, two sulforeductase substrates. The second aim was to evaluate the usefulness of drug degradation half-life generated in simulated colonic bacteria (SCoB) in informing PBPK models. Degradation experiments of sulfinpyrazone and of sulindac in SCoB were performed under anaerobic conditions using recently described methods. For sulfinpyrazone, the abundance of clinical data allowed for construction of a physiologically based pharmacokinetic (PBPK) model and evaluation of luminal degradation clearance determined from SCoB data. For sulindac, the availability of sulindac sulfide and sulindac sulfone standards allowed for evaluating the formation of the main metabolite, sulindac sulfide, during the experiments in SCoB. Both model compounds degraded substantially in SCoB. The PBPK model was able to adequately capture exposure of sulfinpyrazone and its sulfide metabolite in healthy subjects, in ileostomy and/or colectomy subjects, and in healthy subjects pretreated with metoclopramide by implementing degradation half-lives in SCoB to calculate intrinsic colon clearance. Degradation rates of sulindac and formation rates of sulindac sulfide in SCoB were almost identical, in line with in vivo data suggesting the sulindac sulfide is the primary metabolite in the lower intestine. Experiments in SCoB were useful in simulating sulforeductase related bacterial degradation activity in the lower intestine. Degradation half-life calculated from experiments in SCoB is proven useful for informing a predictive PBPK model for sulfinpyrazone.

Photoisomerization of Sulindac and Ozagrel Hydrochloride by Vitamin B2 Catalyst Under Visible Light Irradiation

PURPOSE

Photoisomerization of the E/Z-alkene structures of drugs is a matter of concern as it could result in potency loss and adverse side effects. This study focused on light-induced isomerization of sulindac and ozagrel hydrochloride catalyzed by concomitant vitamin B₂ under light-emitting diode (LED) or fluorescent light.

METHODS

In the presence of 0.05/0.03 equivalents of vitamin B₂/flavin adenine dinucleotide (FAD), sulindac or ozagrel hydrochloride was irradiated with LED light (405 nm) or fluorescent light. The photoisomerization in CD₃OD and D₂O was monitored by ¹H NMR spectroscopy.

RESULTS

Sulindac and ozagrel hydrochloride isomerized in the presence of a catalytic amount of vitamin B₂ or FAD under irradiation of 405 nm LED light and fluorescent light. Irradiation with LED light was found to be more effective than fluorescent light irradiation. The rate of photoisomerization was affected by the solvent, and the reaction in CD₃OD proceeded faster than in D₂O. Furthermore, ozagrel hydrochloride was more prone to isomerization than sulindac.

CONCLUSION

The catalytic activity of vitamin B₂ or FAD was demonstrated in the photoisomerization reaction of sulindac and ozagrel hydrochloride. Considering that the rate of photoisomerization in D₂O is very slow, the possibility of the occurrence of photoisomerization during clinical use is low. However, this study suggests that the interfusion of vitamin B₂ or FAD under excessive light exposure should be avoided as a caution during intravenous administration of sulindac or ozagrel hydrochloride.

Modification of the Release of Poorly Soluble Sulindac with the APTES-Modified SBA-15 Mesoporous Silica

The effectiveness of oral drug administration is related to the solubility of a drug in the gastrointestinal tract and its ability to penetrate the biological membranes. As most new drugs are poorly soluble in water, there is a need to develop novel drug carriers that improve the dissolution rate and increase bioavailability. The aim of this study was to analyze the modification of sulindac release profiles in various pH levels with two APTES ((3-aminopropyl)triethoxysilane)-modified SBA-15 (Santa Barbara Amorphous-15) silicas differing in 3-aminopropyl group content. Furthermore, we investigated the cytotoxicity of the analyzed molecules. The materials were characterized by differential scanning calorimetry, powder X-ray diffraction, scanning and transmission electron microscopy, proton nuclear magnetic resonance and Fourier transformed infrared spectroscopy. Sulindac loaded on the SBA-15 was released in the hydrochloric acidic medium (pH 1.2) and phosphate buffers (pH 5.8, 6.8, and 7.4). The cytotoxicity studies were performed on Caco-2 cell line. The APTES-modified SBA-15 with a lower adsorption capacity towards sulindac released the drug in a less favorable manner. However, both analyzed materials improved the dissolution rate in acidic pH, as compared to crystalline sulindac. Moreover, the SBA-15, both before and after drug adsorption, exhibited insignificant cytotoxicity towards Caco-2 cells. The presented study evidenced that SBA-15 could serve as a non-toxic drug delivery system that enhances the dissolution rate of sulindac and improves its bioavailability.

Sulindac Modulates the Response of Proficient MMR Colorectal Cancer to Anti-PD-L1 Immunotherapy

Immune-checkpoint inhibitor (ICI) therapy has been widely used to treat different human cancers, particularly advanced solid tumors. However, clinical studies have reported that ICI immunotherapy benefits only ∼15% of patients with colorectal cancer, specifically those with tumors characterized by microsatellite instability (MSI), a molecular marker of defective DNA mismatch repair (dMMR). For the majority of patients with colorectal cancer who carry proficient MMR (pMMR), ICIs have shown little clinical benefit. In this study, we examined the efficacy of sulindac to enhance the response of pMMR colorectal cancer to anti-PD-L1 immunotherapy. We utilized a CT26 syngeneic mouse tumor model to compare the inhibitory effects of PD-L1 antibody (Ab), sulindac, and their combination on pMMR colorectal cancer tumor growth. We found that mice treated with combination therapy showed a significant reduction in tumor volume, along with increased infiltration of CD8+ T lymphocytes in the tumor tissues. We also demonstrated that sulindac could downregulate PD-L1 by blocking NF-κB signaling, which in turn led to a decrease in exosomal PD-L1. Notably, PD-L1 Ab can be bound and consumed by exosomal PD-L1 in the blood circulation. Therefore, in combination therapy, sulindac downregulating PD-L1 leads to increased availability of PD-L1 Ab, which potentially improves the overall efficacy of anti-PD-L1 therapy. We also show that low-dose sulindac does not appear to have a systemic inhibitory effect on prostaglandin E2 (PGE2). In conclusion, our findings provide unique insights into the mechanism of action and efficacy for sulindac as an immunomodulatory agent in combination with anti-PD-L1 therapy for the treatment of pMMR colorectal cancer.

Phospho-Sulindac (OXT-328) Inhibits Dry Eye Disease in Rabbits: A Dose-, Formulation- and Structure-Dependent Effect

Purpose: Inflammation of the ocular surface is central to dry eye disease (DED). The anti-inflammatory agent phospho-sulindac (PS) at a high dose was efficacious against DED in a rabbit model. We assessed the dose, formulation and structure dependence of PS's effect. Methods: In rabbits with concanavalin A-induced DED we evaluated a range of PS concentrations (0.05%-1.6%) and dosing frequencies, assessed the duration of its effect with PS in 2 solution formulations and one emulsion formulation, and compared the efficacy of PS to that of sulindac, and of the structurally similar phospho-ibuprofen amide. We determined tear breakup time (TBUT) (tear stability), Schirmer's tear test (tear production), and by esthesiometry corneal sensitivity (symptoms). We also determined the biodistribution in the eye of topically applied PS. Results: PS in a solution formulation, given as eye drops q.i.d. was efficacious starting at a dose of 0.1%. The effect was apparent after 2 days of treatment and lasted at least 8 days after the last dose. Both signs (evidenced by TBUT and Schirmer's test) and symptoms (measured by corneal sensitivity) improved significantly. The best formulation was the solution formulation; a cyclodextrin-based formulation was also successful but the emulsion formulation was not. PS and its metabolites were essentially restricted to the anterior chamber of the eye. Sulindac and phospho-ibuprofen amide had no efficacy on DED. Conclusions: PS is efficacious against DED. Its effect, encompassing signs, and symptoms, are dose, formulation, and structure dependent. PS has therapeutic promise and merits further development.

The efficacy and safety of sulindac for colorectal polyps: A protocol for systematic review and meta-analysis

BACKGROUND

Sulindac has been used for treating colorectal polyps widely. However, the efficacy and safety of sulindac for colorectal polyps are unclear. This study aims to evaluate the efficacy and safety of sulindac for colorectal polyps.

METHODS

Randomized controlled trials of sulindac in the treatment of colorectal polyps will be searched in PubMed, EMbase, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), WanFang, the Chongqing VIP Chinese Science, and Technology Periodical Database, and China biomedical literature database (CBM) from inception to August, 2020. And Baidu Scholar, Google Scholar, International Clinical Trials Registry Platform, and Chinese Clinical Trials Registry will be searched to obtain more relevant studies comprehensively. Two researchers will perform data extraction and risk of bias assessment independently. Statistical analysis will be conducted in RevMan 5.3.

RESULTS

This study will summarize the present evidence by exploring the efficacy and safety of sulindac in the treatment of colorectal polyps.

CONCLUSION

The findings of the study will provide helpful evidence for the efficacy and safety of sulindac in the treatment of colorectal polyps, facilitating clinical practice and further scientific studies.

ETHICS AND DISSEMINATION

The private information from individuals will not publish. This systematic review also will not involve endangering participant rights. Ethical approval is not required. The results may be published in a peer-reviewed journal or disseminated in relevant conferences.

OSF REGISTRATION NUMBER

DOI 10.17605/OSF.IO/N5GDH.

Preparation and Characterization of PVA-Co-PE Drug-Loaded Nanofiber Membrane by Electrospinning Technology

A new transdermal drug delivery system of nanofiber membrane with good biocompatibility and high drug loading was developed by electrospinning technology in this study. Using vinyl alcohol-co-ethylene (PVA-co-PE) polymer as a spinning matrix and non-steroidal anti-inflammatory drug (NSAID) sulindac (SUL) as a model drug, the SUL@PVA-co-PE nanofiber membrane was prepared and characterized systematically. The morphology, molecular vibrational transitions, thermogravimetric attributes, and in vitro drug release and transdermal characteristics of drug-loaded nanofiber membranes were analyzed. The results indicated that the surface of PVA-co-PE nanofibers was uniform and smooth with the diameter ranged from 461 to 696 nm. Notably in vitro simulation experiments demonstrated that SUL@PVA-co-PE nanofiber membrane could provide a continuous drug release to reach the effective concentration of the drug, and exhibited significantly higher cumulative drug permeability compared to commercially available patches, Taken together, PVA-co-PE nanofiber membranes exhibited the characteristics of high drug loading and stability, and represented the potential to be utilized as a new transdermal drug delivery carrier with pronounced development prospect.

Optimizing the timing of colorectal surgery in patients with familial adenomatous polyposis in clinical practice

Background: Familial adenomatous polyposis (FAP) is characterized by the development of hundreds of colorectal adenomas in the second decade of life, and prophylactic colectomy is usually performed around age of 20. A common question is the appropriate timing of surgery and which endoscopic findings indicate surgery. Methods: All FAP patients known at Leiden University Medical Centre from 1985 onwards were included. The patients were then subdivided into those diagnosed before or after 2000. Patient information included age at diagnosis, colonic phenotype, age at surgery, pathological findings and the outcome of follow-up colonoscopies in whom surgery was postponed. Results: The 72 FAP patients identified consisted of 33 patients diagnosed before (group A) and 39 after (group B) 2000. The median age at diagnosis for patients with classical FAP was 18 in groups A and B. All patients diagnosed before 2000 underwent colorectal surgery versus 68% of those diagnosed >2000. The median age at surgery for classical FAP patients was 19 and 24 years in groups A and B, respectively. In patients with intact colon, the number of adenomas gradually increased over many years. Although most adenomas remained <5 mm, the proportion of 5-15 mm adenomas slowly increased. Only one patient developed a high-grade adenoma. None of the patients developed CRC. Conclusions: Surgery today in FAP is performed less often and at a more advanced age. Our experience also suggests that surgery can be safely postponed in selected patients. The most important endoscopic indication for surgery is substantial number of large adenomas of >5-10 mm.

Inhibition of Polyamine Biosynthesis Reverses Ca2+ Channel Remodeling in Colon Cancer Cells

Store-operated Ca²⁺ entry (SOCE) is the most important Ca²⁺ entry pathway in non-excitable cells. Colorectal cancer (CRC) shows decreased Ca²⁺ store content and enhanced SOCE that correlate with cancer hallmarks and are associated to remodeling of store-operated channels (SOCs). Normal colonic cells display small, Ca²⁺-selective currents driven by Orai1 channels. In contrast, CRC cells display larger, non-selective currents driven by Orai1 and transient receptor potential canonical type 1 channels (TRPC1). Difluoromethylornithine (DFMO), a suicide inhibitor of ornithine decarboxylase (ODC), the limiting step in polyamine biosynthesis, strongly prevents CRC, particularly when combined with sulindac. We asked whether DFMO may reverse SOC remodeling in CRC. We found that CRC cells overexpress ODC and treatment with DFMO decreases cancer hallmarks including enhanced cell proliferation and apoptosis resistance. Consistently, DFMO enhances Ca²⁺ store content and decreases SOCE in CRC cells. Moreover, DFMO abolish selectively the TRPC1-dependent component of SOCs characteristic of CRC cells and this effect is reversed by the polyamine putrescine. Combination of DFMO and sulindac inhibit both SOC components and abolish SOCE in CRC cells. Finally, DFMO treatment inhibits expression of TRPC1 and stromal interaction protein 1 (STIM1) in CRC cells. These results suggest that polyamines contribute to Ca²⁺ channel remodeling in CRC, and DFMO may prevent CRC by reversing channel remodeling.

Chemopreventive effect of sulindac in combination with epigallocatechin gallate or kaempferol against 1,2-dimethyl hydrazine-induced preneoplastic lesions in rats: A Comparative Study

A systematic investigation of the chemopreventive effect of sulindac (SL) in combination with either epigallocatechin gallate (EGCG) or kaempferol similar (KMP) has been carried out 1,2-dimethyl hydrazine-treated rats (DMH). Those SL combinations with KMP and EGCG have enhanced the SL activity producing greater antioxidant, anti-inflammatory, antiproliferating, and apoptotic activities in both combinations than SL alone. The chemopreventive effects of SL with both EGCG and KMP were demonstrated by a decrease in thiobaribituric acid reactive substances level, tissue nitric oxide (NO), serum, and tissue β-catenin as well as a reduction in the multiplicity of aberrant crypt foci (ACF) with alleviation in the dysplastic changes that resulted from DMH administration. Down-regulation of proliferating cell nuclear antigen (PCNA) and cyclooxygenase-2 (COX-2) were also confirmed by immunohistochemical staining. The current study paves the way for the use of sulindac combination with kaempferol or EGCG as potential chemopreventive agents against colon cancer with more effect in combination with EGCG.

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.

Celecoxib and sulindac inhibit TGF-β1-induced epithelial-mesenchymal transition and suppress lung cancer migration and invasion via downregulation of sirtuin 1

The non-steroidal anti-inflammatory drugs (NSAIDs) celecoxib and sulindac have been reported to suppress lung cancer migration and invasion. The class III deacetylase sirtuin 1 (SIRT1) possesses both pro- and anticarcinogenic properties. However, its role in inhibition of lung cancer cell epithelial-mesenchymal transition (EMT) by NSAIDs is not clearly known. We attempted to investigate the potential use of NSAIDs as inhibitors of TGF-β1-induced EMT in A549 cells, and the underlying mechanisms of suppression of lung cancer migration and invasion by celecoxib and sulindac. We demonstrated that celecoxib and sulindac were effective in preventing TGF-β1-induced EMT, as indicated by upregulation of the epithelial marker, E-cadherin, and downregulation of mesenchymal markers and transcription factors. Moreover, celecoxib and sulindac could inhibit TGF-β1-enhanced migration and invasion of A549 cells. SIRT1 downregulation enhanced the reversal of TGF-β1-induced EMT by celecoxib or sulindac. In contrast, SIRT1 upregulation promoted TGF-β1-induced EMT. Taken together, these results indicate that celecoxib and sulindac can inhibit TGF-β1-induced EMT and suppress lung cancer cell migration and invasion via downregulation of SIRT1. Our findings implicate overexpressed SIRT1 as a potential therapeutic target to reverse TGF-β1-induced EMT and to prevent lung cancer cell migration and invasion.

Mebendazole and a non-steroidal anti-inflammatory combine to reduce tumor initiation in a colon cancer preclinical model

Inheritance of a gene mutation leads to the initiation of 5 to 10% of most cancers, including colon cancer cases. We developed a chemoprevention strategy using a novel combination of the non-steroidal anti-inflammatory (NSAID) sulindac plus the anthelminthic benzimidazole, mebendazole. This oral drug combination was effective in the Apc^Min/+ mouse model of Familial Adenomatous Polyposis (FAP). Treatment with 35 mg/kg daily mebendazole reduced the number of intestinal adenomas by 56% (P = 0.0002), 160 ppm sulindac by 74% (P < 0.0001), and the combination by 90% (P < 0.0001). The combination significantly reduced microadenomas, polyp number and size in both the small intestines and colon when compared to untreated controls or sulindac alone. Mebendazole as a single agent decreased COX2 expression, blood vessel formation, VEGFR2 phosphorylation, and worked synergistically with sulindac to reduce overexpression of MYC, BCL2, and various pro-inflammatory cytokines. Given the low toxicity of mebendazole, these preclinical findings support the consideration of clinical trials for high risk cancer patients using mebendazole either alone or in combination. The findings have implications for populations with moderate and above risk for developing cancer.

Differentiation by NK cells is a prerequisite for effective targeting of cancer stem cells/poorly differentiated tumors by chemopreventive and chemotherapeutic drugs

Natural Killer (NK) cells target oral, pancreatic, lung, breast, glioblastoma and melanoma stem-like/poorly differentiated tumors. Differentiation of the abovementioned tumors with supernatants from split-anergized NK cells decreases their susceptibility to NK cells, but increases their sensitivity to cisplatin (CDDP)-mediated cell death. Breast and melanoma tumor cells with CD44 knockdown display enhanced susceptibility to NK cell-mediated lysis, potentially due to decreased differentiation. We also demonstrate that sulindac, a non-steroidal anti-inflammatory drug and a chemopreventive agent, not only limits the growth of oral tumor cells, but also aids in cancer cell elimination by NK cells. Treatment of oral tumors with sulindac, but not adriamycin inversely modulates the expression and function of NFκB and JNK, resulting in a significant down-regulation of IL-6, and VEGF secretion by oral tumor cells. In addition, increased secretion of IL-6 and VEGF is blocked by sulindac during interaction of oral tumors with NK cells. Sulindac treatment prevents synergistic induction of VEGF secretion by the tumor cells after their co-culture with untreated NK cells since non-activated NK cells lack the ability to efficiently kill tumor cells. Moreover, sulindac is able to profoundly reduce VEGF secretion by tumor cells cultured with IL-2 activated NK cells, which are able to significantly lyse the tumor cells. Based on the data presented in this study, we propose the following combinatorial approach for the treatment of stem-like/ poorly differentiated tumors in cancer patients with metastatic disease. Stem-like/ poorly differentiated tumor cells may in part undergo lysis or differentiation after NK cell immunotherapy, followed by treatment of differentiated tumors with chemotherapy and chemopreventive agents to eliminate the bulk of the tumor. This dual approach should limit tumor growth and prevent metastasis.

Inhibition of breast cancer cell motility with a non-cyclooxygenase inhibitory derivative of sulindac by suppressing TGFβ/miR-21 signaling

Compelling efficacy on intervention of tumorigenesis by nonsteroidal anti-inflammatory drugs (NSAIDs) has been documented intensively. However, the toxicities related to cyclooxygenase (COX) inhibition resulting in suppression of physiologically important prostaglandins limit their clinical use for human cancer chemoprevention. A novel derivative of the NSAID sulindac sulfide (SS), referred as sulindac sulfide amide (SSA), was recently developed, which lacks COX inhibitory activity, yet shows greater suppressive effect than SS on growth of various cancer cells. In this study, we focus on the inhibitory activity of SSA on breast tumor cell motility, which has not been studied previously. Our results show that SSA treatment at non-cytotoxic concentrations can specifically reduce breast tumor cell motility without influencing tumor cell growth, and the mechanism of action involves the suppression of TGFβ signaling by directly blocking Smad2/3 phosphorylation. Moreover, miR-21, a well-documented oncogenic miRNA for promoting tumor cell metastasis, was also found to be involved in inhibitory activity of SSA in breast tumor cell motility through the modulation of TGFβ pathway. In conclusion, we demonstrate that a non-COX inhibitory derivative of sulindac can inhibit breast tumor metastasis by a mechanism involving the TGFβ/miR-21 signaling axis.

Suppression of β-catenin/TCF transcriptional activity and colon tumor cell growth by dual inhibition of PDE5 and 10

Previous studies suggest the anti-inflammatory drug, sulindac inhibits tumorigenesis by a COX independent mechanism involving cGMP PDE inhibition. Here we report that the cGMP PDE isozymes, PDE5 and 10, are elevated in colon tumor cells compared with normal colonocytes, and that inhibitors and siRNAs can selectively suppress colon tumor cell growth. Combined treatment with inhibitors or dual knockdown suppresses tumor cell growth to a greater extent than inhibition from either isozyme alone. A novel sulindac derivative, ADT-094 was designed to lack COX-1/-2 inhibitory activity but have improved potency to inhibit PDE5 and 10. ADT-094 displayed >500 fold higher potency to inhibit colon tumor cell growth compared with sulindac by activating cGMP/PKG signaling to suppress proliferation and induce apoptosis. Combined inhibition of PDE5 and 10 by treatment with ADT-094, PDE isozyme-selective inhibitors, or by siRNA knockdown also suppresses β-catenin, TCF transcriptional activity, and the levels of downstream targets, cyclin D1 and survivin. These results suggest that dual inhibition of PDE5 and 10 represents novel strategy for developing potent and selective anticancer drugs.

Removal of selected NSAIDs (nonsteroidal anti-inflammatory drugs) in aqueous samples by Octolig®

The possibility of removing representative nonsteroidal anti-inflammatory drugs (NSAIDs) from water was tested using Octolig®, a commercially available material with polyethylenediimine moieties covalently attached to high-surface area silica gel. The effectiveness of removal should depend on selected NSAIDs having appropriate anionic functional groups. NSAIDs selected had aromatic carboxylic groups: diclofenac, fenoprofen, indomethacin, ketoprofen, mefenamic acid, naproxen, and sulindac. These substances in deionized (DI) water were removed by passage over Octolig columns with removal values approaching 90% at environmental pH values, e.g., ca pH 6. Fenoprofen, however, was only removed to an extent of 80% in DI water and 62% in well water, presumably a result of competition with bicarbonate ions.

Syntheses of Platinum-Sulindac Complexes and Their Nanoparticles as Targeted Anticancer Drugs

Platinum(II)-sulindac complexes [{η² -C₅ H₄ SN(O)}Pt(DMSO){O(C=O)Sulindac}], [{η² -C₅ H₄ SN(O)}PtCl{(S=O)Sulindac}], [{η² -C₅ H₄ SN(O)}PtCl{(S=O)Sulindac-succinimide}], and [{η² -C₅ H₄ SN(O)}PtCl{(S=O)Sulindac-thymidine}] were synthesized that exhibited IC₅₀ values of 2.9-4.8 μm against human oral cancer cells OECM1. The poly(lactic-co-glycolic acid) (PLGA) encapsulated [{η² -C₅ H₄ SN(O)}PtCl{(S=O)Sulindac}] also showed cytotoxic activity although less potent than the pristine species.

Sulindac sulfide selectively increases sensitivity of ABCC1 expressing tumor cells to doxorubicin and glutathione depletion

ATP-binding cassette (ABC) transpo rters ABCC1 (MRP1), ABCB1 (P-gp), and ABCG2 (BCRP) contribute to chemotherapy failure. The primary goals of this study were to characterize the efficacy and mechanism of the non­steroidal anti-inflammatory drug (NSAID), sulindac sulfide, to reverse ABCC1 mediated resistance to chemother­apeutic drugs and to determine if sulindac sulfide can influence sensitivity to chemotherapeutic drugs independently of drug efflux. Cytotoxicity assays were performed to measure resistance of ABC-expressing cell lines to doxoru­bicin and other chemotherapeutic drugs. NSAIDs were tested for the ability to restore sensitivity to resistance selected tumor cell lines, as well as a large panel of standard tumor cell lines. Other experiments characterized the mechanism by which sulindac sulfide inhibits ABCC1 substrate and co-substrate (GSH) transport in isolated membrane vesicles and intact cells. Selective reversal of multi-drug resistance (MDR), decreased efflux of doxor­ubicin, and fluorescent substrates were demonstrated by sulindac sulfide and a related NSAID, indomethacin, in resistance selected and engineered cell lines expressing ABCC1, but not ABCB1 or ABCG2. Sulindac sulfide also inhibited transport of leukotriene C₄ into membrane vesicles. Sulindac sulfide enhanced the sensitivity to doxoru­bicin in 24 of 47 tumor cell lines, including all melanoma lines tested (7-7). Sulindac sulfide also decreased intra­cellular GSH in ABCC1 expressing cells, while the glutathione synthesis inhibitor, BSO, selectively increased sensitivity to sulindac sulfide induced cytotoxicity. Sulindac sulfide potently and selectively reverses ABCC1-mediated MDR at clinically achievable concentrations. ABCC1 expressing tumors may be highly sensitive to the direct cytotoxicity of sulindac sulfide, and in combination with chemotherapeutic drugs that induce oxidative stress.

Time-serial Assessment of Drug Combination Interventions in a Mouse Model of Colorectal Carcinogenesis Using Optical Coherence Tomography

Optical coherence tomography (OCT) is a high-resolution, nondestructive imaging modality that enables time-serial assessment of adenoma development in the mouse model of colorectal cancer. In this study, OCT was utilized to evaluate the effectiveness of interventions with the experimental antitumor agent α-difluoromethylornithine (DFMO) and a nonsteroidal anti-inflammatory drug sulindac during early [chemoprevention (CP)] and late stages [chemotherapy (CT)] of colon tumorigenesis. Biological endpoints for drug interventions included OCT-generated tumor number and tumor burden. Immunochistochemistry was used to evaluate biochemical endpoints [Ki-67, cleaved caspase-3, cyclooxygenase (COX)-2, β-catenin]. K-Ras codon 12 mutations were studied with polymerase chain reaction-based technique. We demonstrated that OCT imaging significantly correlated with histological analysis of both tumor number and tumor burden for all experimental groups (P < 0.0001), but allows more accurate and full characterization of tumor number and burden growth rate because of its time-serial, nondestructive nature. DFMO alone or in combination with sulindac suppressed both the tumor number and tumor burden growth rate in the CP setting because of DFMO-mediated decrease in cell proliferation (Ki-67, P < 0.001) and K-RAS mutations frequency (P = 0.04). In the CT setting, sulindac alone and DFMO/sulindac combination were effective in reducing tumor number, but not tumor burden growth rate. A decrease in COX-2 staining in DFMO/sulindac CT groups (COX-2, P < 0.01) confirmed the treatment effect. Use of nondestructive OCT enabled repeated, quantitative evaluation of tumor number and burden, allowing changes in these parameters to be measured during CP and as a result of CT. In conclusion, OCT is a robust minimally invasive method for monitoring colorectal cancer disease and effectiveness of therapies in mouse models.

NSAIDs and Colorectal Cancer Control: Promise and Challenges

The chemoprevention of colorectal cancer (CRC) is a realistic option given the low acceptance and cost of screening colonoscopy. NSAIDs, currently not recommended for CRC prevention, are the most promising agents. Here, we review relevant work and assess the chemopreventive potential of NSAIDs. The chemopreventive efficacy of NSAIDs is established by epidemiological and interventional studies as well as analyses of cardiovascular-prevention randomized clinical trials. The modest chemopreventive efficacy of NSAIDs is compounded by their significant toxicity that can be cumulative. Efforts to overcome these limitations include the use of drug combinations; the emphasis on the early stages of colon carcinogenesis such as aberrant crypt foci, which may require shorter periods of drug administration; and the development of several families of chemically modified NSAIDs such as derivatives of sulindac, nitro-NSAIDs and phospho-NSAIDs, with some of them appearing to have higher safety and efficacy than conventional NSAIDs and thus to be better candidate agents. The successful development of NSAIDs as chemopreventive agents will likely require a combination of the following: identification of subjects at high risk and/or those most likely to benefit from chemoprevention; optimization of the timing, dose and duration of administration of the chemopreventive agent; novel NSAID derivatives and/or combinations of agents; and agents that may prevent other diseases in addition to CRC. Ultimately, the clinical implementation of NSAIDs for the prevention of CRC will depend on a strategy that drastically shifts the currently unacceptable risk/benefit ratio in favor of chemoprevention.

Sulindac has strong antifibrotic effects by suppressing STAT3-related miR-21

Pulmonary fibrosis (PF) is a disease with an unknown cause and a poor prognosis. In this study, we aimed to explore the pathogenesis of PF and the mechanism of sulindac in attenuating bleomycin (BLM)-induced PF. The rat PF model was induced by BLM and verified through histological studies and hydroxyproline assay. The severity of BLM-induced PF in rats and other effects, such as the extent of the wet lung to bw ratios, thickening of alveolar interval or collagen deposition, was obviously ameliorated in sulindac-treated rat lungs compared with BLM-induced lungs. Sulindac also reversed the epithelial mesenchymal transition (EMT) and inhibited the PF process by restoring the levels of E-cadherin and α-smooth muscle actin (SMA) in A549 cells. Our results further demonstrated that the above effects of sulindac might be related to regulating of interferon gamma (IFN-γ) expression, which further affects signal transducers and activators of transcription 3 (STAT3) and phosphorylated STAT3 (p-STAT3) levels. Moreover, higher miR-21 levels with the decreased E-cadherin and increased α-SMA expressions were found in transforming growth factor-β1-treated A549 cells, which can be reversed by sulindac. Collectively, our results demonstrate that by decreasing IFN-γ-induced STAT3/p-STAT3 expression to down-regulate miR-21, sulindac could significantly reverse EMT in A549 cells and prevent BLM-induced PF.

Impact of nonaspirin nonsteroidal anti-inflammatory agents and acetaminophen on sensorineural hearing loss: a systematic review

OBJECTIVE

To perform a systematic review evaluating the association between sensorineural hearing loss and (1) nonsteroidal anti-inflammatory drugs (NSAIDs) as a class, (2) NSAIDs available over the counter, (3) NSAIDs in short intravenous courses, (4) prescription NSAIDs utilized by patients without systemic inflammatory conditions, (5) prescription NSAIDs in patients with arthritides, and (6) acetaminophen with and without concomitant narcotic usage.

DATA SOURCES

Computerized searches of PubMed, EMBASE, and the Cochrane Library were updated through May 2014, along with manual searches and inquiries to topic experts.

REVIEW METHODS

The systematic review was performed according to an a priori protocol. Data extraction was performed by 2 independent investigators, and it focused on relevant audiologic measurements, methodological elements related to risk of bias, and potential confounders.

RESULTS

The 23 criterion-meeting studies included a total of 92,532 participants, with mixed results. Sulindac was the only specific agent to have been studied with formal audiometry in a randomized double-blind placebo-controlled trial in which hearing was the reported primary outcome: Although an effect was seen in the unadjusted analysis (pure tone threshold>15 dB, 9.3% vs 2.9%; relative risk [RR], 3.2; confidence interval [CI], 1.09-9.55; P=.02), the effect dissipated in the adjusted analysis (P=.09). There was a significant effect on self-reported hearing loss from NSAIDs as a class (RR, 1.21; CI, 1.11-1.33), ibuprofen (RR, 1.13; CI, 1.06-1.19), and acetaminophen (RR, 1.21; CI, 1.11-1.33), but no formal audiometric data confirm or refute this suggested effect. Audiometry has demonstrated profound loss in some instances of acetaminophen-narcotic combination ingestions.

CONCLUSIONS

Data are varied regarding the impact of NSAIDs and acetaminophen on population hearing health.

Antenatal exposure to sulindac and risk of necrotizing enterocolitis

OBJECTIVE

Most studies of tocolytics are underpowered to assess drug effects on rare adverse neonatal outcomes. Our aim was to optimize statistical power to assess the influence of sulindac on the rare but severe outcome of necrotizing enterocolitis (NEC) by performing a case-control study.

STUDY DESIGN

A priori sample size of 78 in each group was estimated to detect a 2.5-fold increase in nonsteroidal antiinflammatory drug exposure in NEC cases. Maternal-neonatal charts were reviewed from 2007 through 2012 to yield 110 NEC cases: 68 patients with confirmed NEC by Bell's stage II criteria, and 42 with suspected NEC. Cases and controls (N = 131, matched according to gestational age at delivery, plurality, and delivery date) were compared in rates of antenatal exposures to nonsteroidal antiinflammatory drugs, other tocolytics, and maternal-neonatal characteristics and complications.

RESULTS

Cases and controls were delivered at a mean of 28 weeks. Approximately 52% of the total cohort received tocolytics (26% indomethacin, 15% sulindac, 32% calcium channel blockers, 32% beta-sympathomimetics), with no differences in frequency of use between cases and controls. While there was no difference in indomethacin exposure between cases and controls, antenatal exposure to sulindac was independently associated with increased risk of NEC (adjusted odds ratio, 5.33; 95% confidence interval, 1.38-20.57; P = .02), even after adjustment for other factors significantly associated with NEC.

CONCLUSION

Our data demonstrate an adverse association of sulindac with NEC. These findings deserve further investigation and using sulindac as a tocolytic agent requires caution.

Chemoprevention of colorectal cancer

Colorectal cancer has become one of the most prevalent malignant diseases for both men and women. Patients with inflammatory bowel diseases or certain inherited cancer syndromes are at high risk of developing colorectal cancer and have naturally the highest need for cancer prevention. In familial adenomatous polyposis (FAP) and Lynch syndrome, most of the underlying germline mutations can be detected by DNA sequencing, and medical counselling of affected individuals involves both surveillance tests and chemopreventive measures. However, as the mechanisms leading to colorectal cancer differ in these high-risk groups, the molecular action of chemopreventive drugs needs to be adjusted to the certain pathway of carcinogenesis. In the last decades, a number of drugs have been tested, including sulindac, aspirin, celecoxib, and mesalazine, but some of them are still controversially discussed. This review summarizes the advances and current standards of colorectal cancer prevention in patients with inflammatory bowel disease, FAP and Lynch syndrome.

Pharmacological protection of retinal pigmented epithelial cells by sulindac involves PPAR-α

The retinal pigmented epithelial (RPE) layer is one of the major ocular tissues affected by oxidative stress and is known to play an important role in the etiology of age-related macular degeneration (AMD), the major cause of blinding in the elderly. In the present study, sulindac, a nonsteroidal antiinflammatory drug (NSAID), was tested for protection against oxidative stress-induced damage in an established RPE cell line (ARPE-19). Besides its established antiinflammatory activity, sulindac has previously been shown to protect cardiac tissue against ischemia/reperfusion damage, although the exact mechanism was not elucidated. As shown here, sulindac can also protect RPE cells from chemical oxidative damage or UV light by initiating a protective mechanism similar to what is observed in ischemic preconditioning (IPC) response. The mechanism of protection appears to be triggered by reactive oxygen species (ROS) and involves known IPC signaling components such as PKG and PKC epsilon in addition to the mitochondrial ATP-sensitive K(+) channel. Sulindac induced iNOS and Hsp70, late-phase IPC markers in the RPE cells. A unique feature of the sulindac protective response is that it involves activation of the peroxisome proliferator-activated receptor alpha (PPAR-α). We have also used low-passage human fetal RPE and polarized primary fetal RPE cells to validate the basic observation that sulindac can protect retinal cells against oxidative stress. These findings indicate a mechanism for preventing oxidative stress in RPE cells and suggest that sulindac could be used therapeutically for slowing the progression of AMD.

Anticancer activities of sulindac in prostate cancer cells associated with c-Jun NH2-terminal kinase 1/β-catenin signaling

The non-steroidal anti-inflammatory agent, sulindac, has shown strong effects on cancer prevention in colorectal cancers, however, its anticancer activities on prostate cancer remain unclear. In the current study, human prostate cancer cell lines, LNCaP and PC-3, were treated with various concentrations of sulindac and it was found that sulindac significantly inhibits prostate cancer cell proliferation and promotes cell apoptosis in a dose- and time-dependent manner. Further studies revealed that sulindac significantly induces c-Jun NH2-terminal kinase (JNK) 1 phosphorylation and inhibits β-catenin at the transcriptional and post-transcriptional levels. In conclusion, by targeting the JNK1/β-catenin signaling pathway, sulindac may present a potential preventive or therapeutic agent for treatment of patients with prostate cancer.

CXCR2 inhibition enhances sulindac-mediated suppression of colon cancer development

Small chemical compound sulindac has been approved as a preventive approach against colon cancer for its effectiveness in treatment of precancerous adenoma. Due to its severe toxicities in the cardiovascular, gastrointestinal and renal systems, however, a combination of low-dose sulindac with other chemopreventive agents has been sought after as an alternative therapeutic strategy that could increase its effectiveness, while minimizing its adverse effects. To identify the promising alternative approach, we investigated the therapeutic potential of targeting the interleukin (IL)-8/CXCR2 pathway in colon cancer treatment using both loss-of-function (CXCR2 knockout) and gain-of-function (IL-8 overexpression) mouse models, as the IL-8/CXCR2 pathway has been shown to be activated in intestinal tumors of both human and experimental animals. We found that deletion of CXCR2 gene and ectopic expression of IL-8 suppresses and enhances, respectively, intestinal tumor development caused by a mutation in the APC gene. Moreover, a single copy deletion of CXCR2 gene resulted in abrogation of COX-2 and Gro-α upregulation in intestinal tumors caused by the APC mutation. Moreover, a single copy (heterozygote) deletion of CXCR2 gene was sufficient to synergize with a low-dose sulindac treatment in suppressing APCmin-induced intestinal polyposis. Together, our study provides a therapeutic justification of combined inhibition of CXCR2 and sulindac treatment in colon cancer prevention.

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.

Safety and efficacy of high-dose tamoxifen and sulindac for desmoid tumor in children: results of a Children's Oncology Group (COG) phase II study

BACKGROUND

Desmoid fibromatosis (desmoid tumor, DT) is a soft tissue neoplasm prone to recurrence despite complete surgical resection. Numerous small retrospective reports suggest that non-cytotoxic chemotherapy using tamoxifen and sulindac may be effective for DT. We evaluated the safety and efficacy of tamoxifen and sulindac in a prospective phase II study within the Children's Oncology Group.

PROCEDURES

Eligible patients were <19 years of age who had measurable DT that was recurrent or not amenable to surgery or radiation. The primary objective was to estimate progression-free survival (PFS). Patients received tamoxifen and sulindac daily for 12 months or until disease progression or intolerable toxicity occurred. Response was assessed by magnetic resonance imaging.

RESULTS

Fifty-nine eligible patients were enrolled from 2004 to 2009; 78% were 10-18 years old. Twenty-two (38%) were previously untreated; 15 (41%) of the remaining 37 enrolling with recurrent DT had prior systemic chemotherapy and six (16%) had prior radiation. No life-threatening toxicity was reported. Twelve (40%) of 30 females developed ovarian cysts, which were asymptomatic in 11 cases. Ten patients completed therapy without disease progression or discontinuing treatment. Responses included four partial and one complete (5/59, 8%). The estimated 2-year PFS and survival rates were 36% (95% confidence interval: 0.23-0.48) and 96%, respectively. All three deaths were due to progressive DT.

CONCLUSIONS

Tamoxifen and sulindac caused few serious side effects in children with DT, although ovarian cysts were common. However, the combination showed relatively little activity as measured by response and PFS rates.

Clinical end points for developing pharmaceuticals to manage patients with a sporadic or genetic risk of colorectal cancer

To reduce the morbidity and mortality from colorectal cancer (CRC), current clinical practice focuses on screening for early detection and polypectomy as a form of secondary prevention, complemented with surgical interventions when appropriate. No pharmaceutical agent is currently approved for use in clinical practice for the management of patients at risk for CRC. This article will review earlier attempts to develop pharmaceuticals for use in managing patients with a sporadic or genetic risk of CRC. It will also discuss therapeutic end points under evaluation in current efforts to develop drugs for treating CRC risk factors.

Chemoprevention in familial adenomatous polyposis

Familial adenomatous polyposis (FAP) predictably leads to adenomas and eventual adenocarcinomas in the lower gastrointestinal tract and less frequently, the upper gastrointestinal tract. Chemopreventive strategies have been studied in FAP patients to delay the development of adenomas in the upper and lower gastrointestinal tract, as well as to prevent recurrence of adenomas in the retained rectum of patients after prophylactic surgery with colectomy and ileorectal anastamosis (IRA). The nonsteroidal anti-inflammatory drug (NSAID) sulindac and selective cyclooxygenase-2 (COX-2) inhibitor celecoxib reduce polyposis of the retained rectum after colectomy with IRA. Reports of cardiovascular risks of some NSAIDs and selective COX-2 inhibitors have led to promising studies of lower doses in combination with ursodeoxycholic acid, statin, and difluoromethylornithine. Curcumin and eicosapentaenoic acid show efficacy in small clinical trials of FAP chemoprevention. This article will review the concept of chemoprevention and the current clinical literature in FAP chemoprevention.

Effects of intervention with sulindac and inulin/VSL#3 on mucosal and luminal factors in the pouch of patients with familial adenomatous polyposis

BACKGROUND/AIM

In order to define future chemoprevention strategies for adenomas or carcinomas in the pouch of patients with familial adenomatous polyposis (FAP), a 4-weeks intervention with (1) sulindac, (2) inulin/VSL#3, and (3) sulindac/inulin/VSL#3 was performed on 17 patients with FAP in a single center intervention study. Primary endpoints were the risk parameters cell proliferation and glutathione S-transferase (GST) detoxification capacity in the pouch mucosa; secondary endpoints were the short chain fatty acid (SCFA) contents, pH, and cytotoxicity of fecal water.

METHODS

Before the start and at the end of each 4-week intervention period, six biopsies of the pouch were taken and feces was collected during 24 h. Cell proliferation and GST enzyme activity was assessed in the biopsies and pH, SCFA contents, and cytotoxicity were assessed in the fecal water fraction. The three interventions (sulindac, inulin/VSL#3, sulindac/inulin/VSL#3) were compared with the Mann-Whitney U test.

RESULTS

Cell proliferation was lower after sulindac or VSL#3/inulin, the combination treatment with sulindac/inulin/VSL#3 showed the opposite. GST enzyme activity was increased after sulindac or VSL#3/inulin, the combination treatment showed the opposite effect. However, no significance was reached in all these measures. Cytotoxicity, pH, and SCFA content of fecal water showed no differences at all among the three treatment groups.

CONCLUSION

Our study revealed non-significant decreased cell proliferation and increased detoxification capacity after treatment with sulindac or VSL#3/inulin; however, combining both regimens did not show an additional effect.

Phospho-sulindac (OXT-328), a novel sulindac derivative, is safe and effective in colon cancer prevention in mice

BACKGROUND & AIMS

Nonsteroidal anti-inflammatory drugs (NSAIDs) are effective cancer chemopreventive agents. However, chronic administration of NSAIDs is associated with significant side effects, mainly of the gastrointestinal tract. Given these limitations, we synthesized phospho-sulindac (P-S; OXT-328), a novel sulindac derivative.

METHODS

Here, we evaluated the safety and efficacy of P-S in preclinical models, including its mechanism of action with human colon cancer cell (HCCC) lines and animal tumor models.

RESULTS

(1) Compared with sulindac, P-S is much more potent in inhibiting the growth of cultured HCCCs and more efficacious in preventing the growth of HT-29 xenografts in nude mice. P-S also prevents the growth of intestinal tumors in Apc/Min mice. (2) In combination with difluoromethylornithine (DFMO), P-S reduced tumor multiplicity in Apc/Min mice by 90%. (3) P-S is much safer than sulindac as evidenced by its in vitro toxicologic evaluation and animal toxicity studies. Mechanistically, P-S increases the intracellular levels of reactive oxygen and nitrogen species, which are key early mediators of its chemopreventive effect. Moreover, P-S induces spermidine/spermine N(1)-acetyltransferase enzymatic activity, and together with DFMO it reduces polyamine levels in vitro and in vivo.

CONCLUSIONS

P-S displays considerable safety and efficacy, two pharmacologic properties that are essential for a potential cancer chemopreventive agent, and thus merits further evaluation.

NSAIDs: Old Drugs Reveal New Anticancer Targets

There is compelling evidence that nonsteroidal anti-inflammatory drugs (NSAIDs) and cyclooxygenase-2 selective inhibitors have antineoplastic activity, but toxicity from cyclooxygenase (COX) inhibition and the suppression of physiologically important prostaglandins limits their use for cancer chemoprevention. Previous studies as reviewed here suggest that the mechanism for their anticancer properties does not require COX inhibition, but instead involves an off-target effect. In support of this possibility, recent molecular modeling studies have shown that the NSAID sulindac can be chemically modified to selectively design out its COX-1 and COX-2 inhibitory activity. Unexpectedly, certain derivatives that were synthesized based on in silico modeling displayed increased potency to inhibit tumor cell growth. Other experiments have shown that sulindac can inhibit phosphodiesterase to increase intracellular cyclic GMP levels and that this activity is closely associated with its ability to selectively induce apoptosis of tumor cells. Together, these studies suggest that COX-independent mechanisms can be targeted to develop safer and more efficacious drugs for cancer chemoprevention.

NF-kappaB in carcinoma therapy and prevention

BACKGROUND

NF-kappaB includes a family of signal-activated transcription factors that normally regulate responses to injury and infection but which are aberrantly activated in many carcinomas.

OBJECTIVE

To review the activation and role of NF-kappaB in pathogenesis and as a target for treatment and prevention in carcinoma.

METHODS

Evidence from experimental, epidemiological, preclinical studies and clinical trials cited in the literature are reviewed.

RESULTS/CONCLUSION

Cumulative evidence implicates NF-kappaB in cell survival, inflammation, angiogenesis, spread and therapeutic resistance during tumor development, progression and metastasis of carcinomas. Non-specific natural and synthetic agents that inhibit NF-kappaB have demonstrated activity and safety in prevention or therapy. NF-kappaB-activating kinases and the proteasome are under investigation for targeted prevention and therapy of carcinoma.

Sulindac prevents esophageal adenocarcinomas induced by gastroduodenal reflux in rats

PURPOSE

It is known that cyclooxygenase (COX)-2 expression is increased in Barrett's esophagus and esophageal adenocarcinomas. We studied COX-2 expression and the effect sulindac has on the genesis of Barrett's esophagus and adenocarcinoma in rats undergoing esophagogastroduodenal anastomosis (EGDA).

MATERIALS AND METHODS

Fifty-one rats were divided into a control group (n=27), a 500 ppm sulindac-treated group (n=15) and 1000 ppm sulindac-treated group (n=9). Randomly selected rats were killed by diethyl ether inhalation at 20 and 40 weeks after surgery.

RESULTS

At 40 weeks, rats treated with 1000 ppm sulindac showed narrower esophageal diameter and milder inflammation than the control rats. At 40 weeks, the incidence of Barrett's esophagus was similar between control and sulindac-treated groups, but the incidence of adenocarcinoma was significantly lower in the 1000 ppm sulindac-treated group than either the control or 500 ppm sulindac-treated groups. COX-2 was significantly increased in the lower esophagus of control rats killed at 40 weeks. Cyclin D1 expression was negligible in the sulindac- treated group compared with the control group.

CONCLUSION

We suggest that the chemopreventive effect of sulindac is related to decreased COX-2 and cyclin D1 expression, which may be influenced by reduced inflammation.

Use of transgenic and mutant animal models in the study of heterocyclic amine-induced mutagenesis and carcinogenesis

Heterocyclic amines (HCAs) are potent mutagens generated during the cooking of meat and fish, and several of these compounds produce tumors in conventional experimental animals. During the past 5 years or so, HCAs have been tested in a number of novel in vivo murine models, including the following: lacZ, lacI, cII, c-myc/lacZ, rpsL, and gptDelta. transgenics, XPA-/-, XPC-/-, Msh2+/-, Msh2-/- and p53+/- knock-outs, Apc mutant mice (ApcDelta716, Apc1638N, Apcmin), and A33DeltaNbeta-cat knock-in mice. Several of these models have provided insights into the mutation spectra induced in vivo by HCAs in target and non-target organs for tumorigenesis, as well as demonstrating enhanced susceptibility to HCA-induced tumors and preneoplastic lesions. This review describes several of the more recent reports in which novel animal models were used to examine HCA-induced mutagenesis and carcinogenesis in vivo, including a number of studies which assessed the inhibitory activities of chemopreventive agents such as 1,2-dithiole-3-thione, conjugated linoleic acids, tea, curcumin, chlorophyllin-chitosan, and sulindac.

Induction of apoptosis by sulindac in azoxymethane-induced possible colonic premalignant lesions in rats

We have reported that beta-catenin-accumulated crypts (BCAC), which do not have the appearance of aberrant crypt foci (ACF) are possible colonic premalignant lesions in rats. Suppression of the occurrence and advancement of such lesions should have critical relevance to cancer prevention. This study examined whether sulindac, a chemopreventive nonsteroidal anti-inflammatory drug is able to induce apoptosis in such premalignant lesions. At 6 weeks of age, rats groups 1 - 3 were given azoxymethane (AOM) (15 mg/kg-body weight) once weekly for 3 weeks. Two groups were given sulindac in the diet (200 and 400 ppm), starting at 9 weeks of age. The rats were sacrificed at the termination, and the colons were carefully examined. The incidence and crypt multiplicity of BCAC and ACF were significantly less than those of the control group. The effect of sulindac on the expression of BCAC was greater than that on ACF. Exposure to sulindac significantly increased the apoptotic index (terminal deoxynucleotide transferase dUTP nick-end labeling (TUNEL)-positive cells) in BCAC. However, no significant increase of the index was found in the case of ACF. These results suggest that the chemopreventive effect of sulindac in rats is related to the induction of apoptosis in premalignant lesions. Our results also provide additional evidence that BCAC are premalignant lesions in colon carcinogenesis in rodents.

Growth inhibition and apoptosis induction of Sulindac on Human gastric cancer cells

AIM: To evaluate the effects of sulindac in inducing growth inhibition and apoptosis of human gastric cancer cells in comparison with human hepatocellular carcinoma (HCC) cells.

METHODS: The human gastric cancer cell lines MKN45 and MKN28 and human hepatocellular carcinoma cell lines HepG₂ and SMMC7721 were used for the study. Anti-proliferative effect was measured by MTT assay, and apoptosis was determined by Hoechst-33258 staining, electronography and DNA fragmentation. The protein of cyclooxygenase-2 (COX-2) and Bcl-2 were detected by Western dot blotting.

RESULTS: Sulindac could initiate growth inhibition and apoptosis of MKN45, MKN28, HepG₂ and SMMC7721 cells in a dose-and time-dependent manner. Growth inhibitory activity and apoptosis were more sensitive in HepG₂ cells than in SMMC7721 cells, MKN45 and MKN28 cells. After 24 h incubation with sulindac at 2 mmol•L¯¹ and 4 mmol•L¯¹, the level of COX-2 and Bcl-2 protein were lowered in MKN45, SMMC7721 and HepG₂ cells but not in MKN28 cells.

CONCLUSION: Sulindac could inhibit the growth of gastric cancer cells and HCC cells effectively in vitro by apoptosis induction, which was associated with regression of COX- 2 and Bcl-2 expression. The growth inhibition and apoptosis of HCC cells were greater than that of human gastric cancer cells. The different effects of apoptosis in gastric cancer cells may be related to the differentiation of the cells.

Tissue prostanoids as biomarkers for chemoprevention of colorectal neoplasia: correlation between prostanoid synthesis and clinical response in familial adenomatous polyposis

Recent studies indicate that sulindac, a nonsteroidal anti-inflammatory drug (NSAID), lowers mucosal prostanoid levels and regresses colorectal adenomas in patients with familial adenomatous polyposis (FAP). To determine whether they are biomarkers for sulindac-mediated chemoprevention of colorectal adenomas, levels of 5 prostanoids [prostaglandin (PG) D2, PGE2, PGF2alpha, thromboxane B2, and 6-keto-PGF1alpha] in the normal-appearing rectal mucosa from 7 FAP patients with a history of subtotal colectomy and ileorectal anastomosis and 4 FAP patients without surgery, were measured in the absence or presence of exogenously added arachidonic acid before the initiation and at the end of 3 months of sulindac treatment. The addition of arachidonic acid resulted in a uniform increase in the levels of all 5 prostanoids although this increase was selectively attenuated in patients with ileorectal anastomosis who took sulindac. In the latter patients, arachidonic acid also augmented the inhibition of prostanoid synthesis by sulindac. In contrast, sulindac failed to attenuate the increase in prostanoid levels resulting from arachidonic acid in patients without previous surgery. Importantly, when measured in the presence of arachidonic acid, the reduction in the levels of all 5 prostanoids due to sulindac was statistically correlated with a reduction in the size and number of adenomas in the two groups of patients combined. These results suggest that tissue prostanoids measured in the presence of arachidonic acid may serve as sensitive and reliable biomarkers in monitoring the clinical responsiveness of FAP patients undergoing chemoprevention for colorectal neoplasia with NSAIDs.

Sulindac sulfide, but not sulindac sulfone, inhibits colorectal cancer growth

Sulindac sulfide, a metabolite of the nonsteroidal antiinflammatory drug (NSAID) sulindac sulfoxide, is effective at reducing tumor burden in both familial adenomatous polyposis patients and in animals with colorectal cancer. Another sulindac sulfoxide metabolite, sulindac sulfone, has been reported to have antitumor properties without inhibiting cyclooxygenase activity. Here we report the effect of sulindac sulfone treatment on the growth of colorectal carcinoma cells. We observed that sulindac sulfide or sulfone treatment of HCA-7 cells led to inhibition of prostaglandin E2 production. Both sulindac sulfide and sulfone inhibited HCA-7 and HCT-116 cell growth in vitro. Sulindac sulfone had no effect on the growth of either HCA-7 or HCT-116 xenografts, whereas the sulfide derivative inhibited HCA-7 growth in vivo. Both sulindac sulfide and sulfone inhibited colon carcinoma cell growth and prostaglandin production in vitro, but sulindac sulfone had no effect on the growth of colon cancer cell xenografts in nude mice.

Prostaglandin levels in human colorectal mucosa: effects of sulindac in patients with familial adenomatous polyposis

Recent evidence suggests that nonsteroidal antiinflammatory drugs (NSAIDs) may prevent colorectal cancer. The mechanism of action of NSAIDs in chemoprevention is unknown but may be linked to their effect on mucosal prostaglandin levels. Levels of five major prostaglandin metabolites were measured by gas chromatography-mass spectrometry in biopsy specimens of flat rectal mucosa from four patients with familial adenomatous polyposis (FAP) before and after sulindac therapy and from five healthy individuals. The prostaglandin present at highest concentration in rectal mucosa from FAP and control subjects was prostaglandin E2. The concentration of thromboxane B2 alone was significantly elevated in FAP patients compared to controls (P = 0.016). In FAP patients treated with sulindac, all prostaglandin metabolite levels were significantly reduced compared to pretreatment levels (P < 0.05) except prostaglandin D2 (P = 0.07). Prostaglandins D2, E2, F2alpha, and 6-keto-F1alpha levels also were significantly reduced in FAP patients on sulindac compared to healthy controls (P < 0.05). However, interpatient heterogeneity of response to sulindac was evident with changes ranging from +19% to -89%, and the patient with the greatest reductions after sulindac developed colorectal cancer after 35 months of therapy. Sulindac treatment, at drug doses shown to regress colorectal adenomas in FAP patients, has heterogeneous effects on the level of major prostaglandins in their rectal mucosa and may not prevent colorectal cancer due to uncoupling of prostaglandin levels and carcinogenesis.

The influence of indomethacin and sulindac on some pharmacological actions of atenolol in hypertensive patients

Indomethacin and sulindac were used as tools to study the role of renal and/or systemic prostaglandins in the pharmacological response to atenolol. Patients receiving chronic treatment with atenolol 100 mg received indomethacin 50 mg twice daily or sulindac 200 mg twice daily in a randomised crossover trial. Indomethacin significantly reduced the antihypertensive action of atenolol while sulindac had no effect. The role that systemic and/or renal prostaglandins may play in the antihypertensive action of atenolol is discussed with reference to renal PGI2 production and inhibition of platelet cyclo-oxygenase.