sulindac and Neoplasms

Although numerous reports conclude that nonsteroidal anti-inflammatory drugs (NSAIDs) have anticancer activity, this common drug class is not recommended for long-term use because of potentially fatal toxicities from cyclooxygenase (COX) inhibition. Studies suggest the mechanism responsible for the anticancer activity of the NSAID sulindac is unrelated to COX inhibition but instead involves an off-target, phosphodiesterase (PDE). Thus, it might be feasible develop safer and more efficacious drugs for cancer indications by targeting PDE5 and PDE10, which are overexpressed in various tumors and essential for cancer cell growth. In this review, we describe the rationale for using the sulindac scaffold to design-out COX inhibitory activity, while improving potency and selectivity to inhibit PDE5 and PDE10 that activate cGMP/PKG signaling to suppress Wnt/β-catenin transcription, cancer cell growth, and tumor immunity.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Antineoplastic Agents; beta Catenin; Cyclic GMP; Cyclic GMP-Dependent Protein Kinases; Humans; Neoplasms; Phosphodiesterase Inhibitors; Signal Transduction; Sulindac; Transcription, Genetic; Wnt Proteins

The oxidative pentose phosphate pathway (PPP) contributes to tumour growth, but the precise contribution of 6-phosphogluconate dehydrogenase (6PGD), the third enzyme in this pathway, to tumorigenesis remains unclear. We found that suppression of 6PGD decreased lipogenesis and RNA biosynthesis and elevated ROS levels in cancer cells, attenuating cell proliferation and tumour growth. 6PGD-mediated production of ribulose-5-phosphate (Ru-5-P) inhibits AMPK activation by disrupting the active LKB1 complex, thereby activating acetyl-CoA carboxylase 1 and lipogenesis. Ru-5-P and NADPH are thought to be precursors in RNA biosynthesis and lipogenesis, respectively; thus, our findings provide an additional link between the oxidative PPP and lipogenesis through Ru-5-P-dependent inhibition of LKB1-AMPK signalling. Moreover, we identified and developed 6PGD inhibitors, physcion and its derivative S3, that effectively inhibited 6PGD, cancer cell proliferation and tumour growth in nude mice xenografts without obvious toxicity, suggesting that 6PGD could be an anticancer target.

Topics: AMP-Activated Protein Kinase Kinases; AMP-Activated Protein Kinases; Humans; Lipogenesis; Neoplasms; Oxidative Stress; Pentose Phosphate Pathway; Phosphogluconate Dehydrogenase; Protein Serine-Threonine Kinases; Ribulosephosphates; Signal Transduction

Non-steroidal anti-inflammatory drugs (NSAIDs) are used extensively for analgesic and antipyretic treatments. In addition, NSAIDs reduce the risk and mortality to several cancers. Their mechanisms in anti-tumorigenesis are not fully understood, but both cyclooxygenase (COX)-dependent and -independent pathways play a role. We and others have been interested in elucidating molecular targets of NSAID-induced apoptosis. In this review, we summarize updated literature regarding cellular and molecular targets modulated by NSAIDs. Among those NSAIDs, sulindac sulfide and tolfenamic acid are emphasized in this review because these two drugs have been well investigated for their anti-tumorigenic activity in many different types of cancer.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Antineoplastic Agents; Humans; Neoplasms; ortho-Aminobenzoates; Prostaglandin-Endoperoxide Synthases; Sulindac

Cancer chemoprevention approaches generally use long-term, continuous treatment, which can produce major preventive effects but which can also have unexpected serious adverse events. This raises the question of whether intermittent dosing schedules might reduce toxicity while retaining benefit, a concept that we call short-term intermittent therapy to eliminate premalignancy (SITEP). Recent preclinical studies support a novel SITEP approach whereby short-term, intermittent therapy eliminates premalignant cells via apoptosis that is induced by synthetic lethal interactions. Synthetic lethality allows personalized, selective elimination of premalignant clones without harming normal cells. This Opinion article provides a detailed discussion of the principle, method and future development of the SITEP approach.

Topics: Animals; Chemoprevention; Genes, APC; Humans; Mice; Neoplasms; Precancerous Conditions; Proto-Oncogene Proteins; Proto-Oncogene Proteins p21(ras); ras Proteins; Sulindac; TNF-Related Apoptosis-Inducing Ligand

Statins and nonsteroidal antiinflammatory drugs (NSAIDs) are commonly prescribed for lowering cholesterol and anti-inflammation, respectively. Recently, their potential roles as cancer chemopreventive agents have been subject to intensive studies. Human trials have not provided conclusive results on the protective effects of statins against different cancers, while more convincing results have been observed for cancer preventive effects of NSAIDs, especially on colorectal cancer. A promising strategy to enhance the cancer preventive efficacy of statins and NSAIDs is to use them in combination, which may produce synergy and lower the dose required for each agent. This strategy is of particular interest for potential use of low doses of statins and NSAIDs on a long-term basis for cancer chemoprevention; increased risks for gastrointestinal and cardiovascular side effects associated with the use of NSAIDs have been observed in colorectal cancer chemopreventive trials. This article reviews the evidence for the cancer preventive actions of statins and NSAIDs, as well as their possible synergistic action and the mechanisms involved.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Anticarcinogenic Agents; Aspirin; Atorvastatin; Celecoxib; Colorectal Neoplasms; Drug Administration Schedule; Drug Synergism; Drug Therapy, Combination; Evidence-Based Medicine; Fatty Acids, Monounsaturated; Fluvastatin; Heptanoic Acids; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Indoles; Lovastatin; Meta-Analysis as Topic; Neoplasms; Pravastatin; Pyrazoles; Pyridines; Pyrroles; Randomized Controlled Trials as Topic; Simvastatin; Sulfonamides; Sulindac

Nonsteroidal antiinflammatory drugs (NSAIDs) induce apoptosis in a variety of cancer cells, including those of colon, prostate, breast and leukemia. In addition, the classical NSAIDs sulindac and aspirin are promising chemopreventive agents against colon cancer. NSAIDs inhibit cyclooxygenases (COX) preventing the formation of prostaglandins, prostacyclin and thromboxane. NSAIDs also exert other biological effects, including generation of reactive oxygen species (ROS) and inhibition of NF-kappaB-mediated signals. Despite many suggested mechanisms for their anticancer effects, it remains uncertain how they induce cell cycle arrest and apoptosis in cancer cells. Furthermore, there is little information on the selectivity of NSAIDs-mediated anticancer effects, although this is one of the most important issues in cancer therapy. Increased understanding of the biological basis for the anticancer activity of NSAIDs and their selectivity is essential for future therapeutic advances. In this paper, we propose that increased ROS generation is one of the key mechanisms for NSAIDs-mediated anticancer effects on various cancer cells.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Chemoprevention; DNA Damage; Female; Humans; Male; Neoplasms; Oxidative Stress; Sulindac

Apoptosis is a form of cell death that permits the removal of damaged, senescent or unwanted cells in multicellular organisms, without damage to the cellular microenvironment. Defective apoptosis represents a major causative factor in the development and progression of cancer. The majority of chemotherapeutic agents, as well as radiation, utilize the apoptotic pathway to induce cancer cell death. Resistance to standard chemotherapeutic strategies also seems to be due to alterations in the apoptotic pathway of cancer cells. Recent knowledge on apoptosis has provided the basis for novel targeted therapies that exploit apoptosis to treat cancer. These new target include those acting in the extrinsic/intrinsic pathway, proteins that control the apoptosis machinery such as the p53 and proteosome pathway. Most of these forms of therapy are still in preclinical development because of their low specifity and susceptibility to drug resistance, but several of them have shown promising results. In particular, this review specifically aims at providing an update of certain molecular players that are already in use in order to target apoptosis (such as bortezomib) or which are still being clinically evaluated (such ONYX-015, survivin and exisulind/aptosyn) or which, following preclinical studies, might have the necessary requirements for becoming part of the anticancer drug programs (such as TRAIL/Apo2L, apoptin/VP3).

Topics: Animals; Antineoplastic Agents; Apoptosis; Boronic Acids; Bortezomib; Capsid Proteins; Humans; Inhibitor of Apoptosis Proteins; Ligands; Microtubule-Associated Proteins; Neoplasm Proteins; Neoplasms; Pyrazines; Receptors, Death Domain; Sulindac; Survivin; TNF-Related Apoptosis-Inducing Ligand

Exisulind [Aptosyn trade mark, FGN 1 trade mark, Prevatac trade mark, sulindac sulfone], the sulfone derivative of sulindac, is the lead compound in a series of selective apoptotic antineoplastic drugs (SAANDs) being developed by OSI Pharmaceuticals. The compounds were originally developed by Cell Pathways, which was acquired by, and integrated into, OSI Pharmaceuticals in June 2003. Exisulind inhibits the enzyme cyclic GMP phosphodiesterase (GMP-PDE), overexpressed in precancerous and cancerous colorectal cells, and induces apoptosis in such cells with minimal effects on normal cells. This apoptotic effect is independent of COX I or COX II inhibition, p53, Bcl-2, or cell-cycle arrest. Preclinical evidence suggests that exisulind also inhibits angiogenesis. Cell Pathways has formed sales and distribution agreements with three healthcare-related companies in the US for its future marketing and support campaign for exisulind. Innovex will hire and train sales representatives for Cell Pathways to launch and promote exisulind, Livingston Healthcare Services will be responsible for customer service, order and distribution administration, and Lash Group will be responsible for the development and implementation of reimbursement support services for exisulind. Cell Pathways has issued an exclusive licence for exisulind to Paladin Labs of Montreal, Canada. The agreement allows Paladin exclusive rights to commercialise the drug in Canada. In August 1999 Cell Pathways submitted an NDA application to the US FDA for exisulind (Aptosyn) for the treatment of familial adenomatous polyposis (FAP). However, in September 2000, the FDA announced that it had found deficiencies in the safety and efficacy data of Cell Pathways' NDA, and returned a non-approvable letter to the company. Cell Pathways then initiated another phase III study of the agent in combination with Aventis' docetaxel and comparing combination therapy with docetaxel alone. Exisulind has fast-track designation for FAP in the US. Phase I and II paediatric trials are also underway in the US. Cell Pathways announced in April 2000 that it had completed enrollment in an open-label phase II study in children with familial adenomatous polyposis (FAP). Patients will be evaluated to determine whether polyp numbers have been reduced after 1 year relative to baseline. In June 2000, Cell Pathways announced the results of a 1-year extension of a 1997-1999 phase III trial that showed that exisulind significantly reduced p

Topics: Animals; Antineoplastic Agents; Apoptosis; Clinical Trials as Topic; Humans; Neoplasms; Sulindac

OSI Pharmaceuticals is developing OSI-461, a potent analog of exisulind, for the potential treatment of cancer and inflammatory bowel disease. In August 2001, OSI-461 entered phase II trials involving patients with chronic lymphocytic leukemia. In July 2002, the company embarked on a pilot phase II study evaluating OSI-461 for the treatment of Crohn's disease. By October 2002, Cell Pathways had selected hormone-refractory prostate cancer as the lead cancer indication for clinical development of OSI-461.

Topics: Animals; Antineoplastic Agents; Clinical Trials, Phase I as Topic; Clinical Trials, Phase II as Topic; Drugs, Investigational; Humans; Inflammatory Bowel Diseases; Neoplasms; Phosphodiesterase Inhibitors; Sulindac

Exisulind (Aptosyn, Cell Pathways, Inc.) is the first of a new class of targeted, pro-apoptotic drugs that show promise in the treatment of cancer. These agents induce apoptosis (i.e., programmed cell death) in a broad range of pre-cancerous and cancerous tissues without affecting normal cells. The antineoplastic effect of exisulind appears to be the result of activation of protein kinase G (PKG) which leads to multiple downstream effects culminating in apoptosis. Exisulind has demonstrated antineoplastic activity in solid tumour and haematological cancer cell lines and is an inhibitor of tumour growth in rodent models of colon, prostate, bladder, mammary and lung cancer. Preclinical data evaluating selective apoptotic antineoplastic drugs (SAANDs) in combination with various chemotherapy drugs indicates additive or synergistic antineoplastic effects. In clinical studies, exisulind prevented colorectal polyp formation in patients with familial adenomatous polyposis (FAP) over 24 months. In a randomised, placebo-controlled study of prostate cancer patients, exisulind inhibited the rise of prostate-specific antigen (PSA) in men with PSA progression after radical prostatectomy. Exisulind has been well-tolerated by most patients in clinical trials. In conclusion, preclinical evidence and early clinical results suggest that exisulind and other drugs in this class may have wide applications in treating cancer both as monotherapy and in combination with chemotherapy and other targeted agents.

Topics: Antineoplastic Agents; Apoptosis; Clinical Trials as Topic; Humans; Neoplasms; Sulindac

1.Sulindac, cis-5-fluoro-2-methyl-1-(p-methylsulphinylbenzylidene)indene-3-ace tic acid, inhibits growth of colon polyps and cancers. This effect has been attributed to inhibition of prostaglandin synthesis but more recent observations indicate that, in vitro, cells that do not have cyclo-oxygenase nor RNA for synthesis of such enzymes are affected by sulindac. Therefore the presumptive effect is probably not correct.2.It has also been found that sulindac stimulates apoptosis. It is herein postulated that in tumour cells such effects may be due to interaction of the anionic form of the drug with protons in the intermembrane space of mitochondria to disrupt the potential across the inner mitochondrial membrane and thereby initiate apoptosis. Normal cells are not affected.

Topics: Anti-Inflammatory Agents, Non-Steroidal; Apoptosis; Humans; Intracellular Membranes; Membrane Potentials; Mitochondria; Neoplasms; Piroxicam; Stimulation, Chemical; Sulindac

The rate-limiting step in arachidonate metabolism is mediated by enzymes known as cyclooxygenases (COXs). These enzymes catalyze the biosynthesis of prostaglandin H2, the precursor of molecules such as prostaglandins, prostacyclin, and thromboxanes. The COX enzyme family consists of the classical COX-1 enzyme, which is constitutively expressed in many tissues, and a second isozyme, i.e., COX-2, which is induced by various stimuli, such as mitogens and cytokines, and is involved in many inflammatory reactions. Because nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit both COX-1 and COX-2, these drugs also cause unwanted side effects, exemplified by gastrointestinal bleeding. Accumulating evidence indicates that NSAIDs can reduce the incidence of colorectal cancers in human and experimental animals and can reduce the number and size of polyps in patients with familial adenomatous polyposis. This Part II (of a two-part review) focuses on the growing clinical and experimental evidence that NSAIDS and COX-2 inhibitors can influence the risk of colon (and possibly of other) cancers.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Clinical Trials as Topic; Colorectal Neoplasms; Cyclooxygenase 1; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Cyclooxygenase Inhibitors; Enzyme Induction; Humans; Isoenzymes; Membrane Proteins; Neoplasms; Neoplasms, Experimental; Prostaglandin-Endoperoxide Synthases; Prostaglandins; Sulindac

To find the maximum tolerated dose (MTD) of OSI-461 in combination with mitoxantrone in patients with advanced solid tumors.. This was a Phase I study using cohort dose escalation of OSI-461 dosed orally twice daily in combination with mitoxantrone 12 mg/m(2) given on Day 1 of each 21-day cycle.. OSI-461 dose was escalated to 1,000 mg po bid. One patient experienced a dose-limiting toxicity (DLT). Three patients discontinued the study due to adverse events (AE). Two patients (10%) had a partial response, and ten patients (50%) had stable disease as best response.. The combination of OSI-461 and mitoxantrone was well tolerated. Dose escalation was stopped because of toxicities in a concurrent Phase I trial. The response rate seen in patients with prostate cancer was comparable to response rates seen in trials of mitoxantrone and prednisone alone, and further studies of the combination of OSI-461 and mitoxantrone were not pursued.

Topics: Aged; Aged, 80 and over; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Breast Neoplasms; Female; Humans; Male; Maximum Tolerated Dose; Middle Aged; Mitoxantrone; Neoplasms; Prostatic Neoplasms; Sulindac; Testicular Neoplasms; Treatment Outcome; Urinary Bladder Neoplasms

Multi-drug resistance mediated by ATP-binding cassette trans-membrane protein pumps is an important cause of cancer treatment failure. Sulindac has been shown to be a competitive substrate for the clinically important resistance protein, multi-drug resistance protein-1 (MRP-1), and thus might enhance the anti-cancer activity of substrate chemotherapeutic agents, e.g. anthracyclines.. We conducted a dose-escalating, single arm, prospective, open label, non-randomised phase I trial of epirubicin (75 mg/m(2)) in combination with escalating oral doses of sulindac (0-800 mg) in patients with advanced cancer to identify an appropriate dose of sulindac to use in future resistance studies. Anthracycline and sulindac pharmacokinetics were studied in cycles 1 and 3.. Seventeen patients (8 breast, 3 lung, 2 bowel, 1 melanoma, 1 renal, 1 ovarian and 1 of unknown primary origin, 16/17 having had prior chemotherapy) were enrolled. Eight patients received a full six cycles of treatment; 14 patients received three or more cycles. Dose-limiting toxicity was observed in two patients at 800 mg sulindac (1 renal impairment, 1 fatal haemoptysis in a patient with advanced lung cancer), and sulindac 600 mg was deemed to be the maximum tolerated dose. Sulindac had no effect on epirubicin pharmacokinetics. Among 15 patients with evaluable tumour, two partial responses were seen (malignant melanoma and breast cancer). Four others had prolonged stable disease.. Epirubicin 75 mg/m(2) and sulindac 600 mg are the recommended doses for phase II studies for these agents in combination.

Topics: Adult; Aged; Anti-Inflammatory Agents, Non-Steroidal; Antibiotics, Antineoplastic; ATP Binding Cassette Transporter, Subfamily B, Member 1; Chemotherapy, Adjuvant; Creatinine; Dose-Response Relationship, Drug; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Epirubicin; Female; Humans; Immunohistochemistry; Male; Middle Aged; Myocardium; Neoplasms; Platelet Count; Prospective Studies; Sulindac; Troponin

The objective of this phase I study was to determine the maximal tolerated dose (MTD) of the combination of weekly docetaxel and exisulind in patients with advanced solid tumors.. Patients with advanced or refractory solid tumors were treated with intravenous weekly docetaxel with daily oral exisulind. The following dose levels (docetaxel/exisulind) were explored: 30-mg/m2/200 mg po bid, 35/200, 35/250 and 40/250. Docetaxel was administered weekly for 6 weeks followed by 2 weeks off, and exisulind was taken twice daily. Each cycle was 8 weeks.. Eighteen patients were enrolled in the study. All of them had received prior systemic therapy. Most patients had either melanoma or carcinomas of the upper gastrointestinal tract. A total of 31 cycles of therapy were administered. DLTs were grade 3 diarrhea, anorexia and fatigue and grade 3 cutaneous toxicity at dose level 4 (40/250). Myelosuppression was mild. Fatigue and gastrointestinal toxicity (anorexia, dyspepsia, nausea, abdominal pain and diarrhea) represented the most common toxicities. However, grade 3 and grade 4 toxicities were uncommon. There were no treatment related deaths. No objective responses were observed and five patients achieved stable disease.. The recommended dose for phase II studies is weekly docetaxel 35 mg/m2 for 6 weeks followed by 2 weeks off in combination with oral exisulind 250 mg po bid. This combination is feasible and well-tolerated at these doses.

Topics: Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Docetaxel; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Humans; Male; Maximum Tolerated Dose; Middle Aged; Neoplasms; Sulindac; Taxoids

CP-461 is a member of a class of novel proapoptotic drugs that specifically inhibit cyclic GMP phosphodiesterases but not cyclooxygenase-1 or -2. CP-461 inhibits the growth of a broad range of human tumor cell lines in vitro at micromolar concentrations and selectively induces apoptosis in cancer cell lines but not normal cells. Preclinical studies revealed good oral bioavailability and no toxicity in dogs and rats at single doses up to 500 mg/kg. In a Phase I trial, 21 patients with a range of solid tumors and good performance status received CP-461 p.o. twice daily for 28 consecutive days. Cycles were repeated without a treatment-free interval. CP-461 doses ranged from 100 to 800 mg/day. Therapy was well tolerated overall, and a maximum tolerated dose was not reached. Grade 3 asymptomatic aspartate aminotransferase/alanine aminotransferase elevation in 1 patient treated at 800 mg/day was the only dose-limiting toxicity. No hematologic toxicity was noted. Peak plasma concentrations occurred between 1 and 2 h after dosing, and doses above 200 mg/day exceeded the known in vitro EC(50) (1-2 micro M) for apoptosis in cancer cells. No drug was detectable after 24 h of administration, and the terminal half-life was 6.7 h. The area under the plasma concentration-time curve was dose-proportional from 200 to 800 mg/day. Four patients exhibited disease stability after two cycles of treatment. CP-461 is minimally toxic at doses up to 800 mg/day when administered p.o. on a twice-daily schedule.

Topics: Adult; Aged; Aged, 80 and over; Alanine Transaminase; Aspartate Aminotransferases; D-Alanine Transaminase; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Humans; Male; Maximum Tolerated Dose; Middle Aged; Neoplasms; Phosphodiesterase Inhibitors; Sulindac; Tissue Distribution

Exisulind (Aptosyn, Cell Pathways, Inc.) is the first of a new class of targeted, pro-apoptotic drugs that show promise in the treatment of cancer. These agents induce apoptosis (i.e., programmed cell death) in a broad range of pre-cancerous and cancerous tissues without affecting normal cells. The antineoplastic effect of exisulind appears to be the result of activation of protein kinase G (PKG) which leads to multiple downstream effects culminating in apoptosis. Exisulind has demonstrated antineoplastic activity in solid tumour and haematological cancer cell lines and is an inhibitor of tumour growth in rodent models of colon, prostate, bladder, mammary and lung cancer. Preclinical data evaluating selective apoptotic antineoplastic drugs (SAANDs) in combination with various chemotherapy drugs indicates additive or synergistic antineoplastic effects. In clinical studies, exisulind prevented colorectal polyp formation in patients with familial adenomatous polyposis (FAP) over 24 months. In a randomised, placebo-controlled study of prostate cancer patients, exisulind inhibited the rise of prostate-specific antigen (PSA) in men with PSA progression after radical prostatectomy. Exisulind has been well-tolerated by most patients in clinical trials. In conclusion, preclinical evidence and early clinical results suggest that exisulind and other drugs in this class may have wide applications in treating cancer both as monotherapy and in combination with chemotherapy and other targeted agents.

Topics: Antineoplastic Agents; Apoptosis; Clinical Trials as Topic; Humans; Neoplasms; Sulindac

The Wnt pathway is dysregulated and activated in many human malignancies. More than 90% of colon cancers have variations in the Wnt pathway. Sulindac, a drug that targets protein Dvl of the Wnt/Dvl/β-catenin pathway, which regulates cancer gene expression, has been reported to significantly reduce the incidence and the risk of death from colorectal cancer and other types of cancer. Herein, a dual functional compound (

Topics: Animals; beta Catenin; Chlorocebus aethiops; Colonic Neoplasms; COS Cells; Dishevelled Proteins; Female; Fluorescent Dyes; Gene Expression Regulation, Neoplastic; Humans; MCF-7 Cells; Mice; Mice, Nude; Neoplasms; Neoplasms, Experimental; Optical Imaging; Sulindac; Wnt Proteins

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.. 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.

Topics: Anti-Inflammatory Agents, Non-Steroidal; Antineoplastic Agents; Cell Line, Tumor; Chromatography, High Pressure Liquid; Chromatography, Thin Layer; Drug Design; Drug Screening Assays, Antitumor; Female; Heterografts; Humans; Male; Neoplasms; Oxazoles; Proton Magnetic Resonance Spectroscopy; Spectrometry, Mass, Electrospray Ionization; Sulindac; Thiazoles

Sulindac is a non-steroidal anti-inflammatory drug (NSAID) that has shown significant anticancer activity. Sulindac sulfide amide (1) possessing greatly reduced COX-related inhibition relative to sulindac displayed in vivo antitumor activity that was comparable to sulindac in a human colon tumor xenograft model. Inspired by these observations, a panel of diverse sulindac amide derivatives have been synthesized and their activity probed against three cancer cell lines (prostate, colon and breast). A neutral analog, compound 79 was identified with comparable potency relative to lead 1 and activity against a panel of lymphoblastic leukemia cell lines. Several new series also show good activity relative to the parent (1), including five analogs that also possess nanomolar inhibitory potencies against acute lymphoblastic leukemia cells. Several new analogs identified may serve as anticancer lead candidates for further development.

Topics: Amides; Antineoplastic Agents; Cell Survival; Drug Screening Assays, Antitumor; Humans; Neoplasms; Structure-Activity Relationship; Sulindac

Retinoid X receptor-alpha (RXRα), an intriguing and unique drug target, can serve as an intracellular target mediating the anticancer effects of certain nonsteroidal anti-inflammatory drugs (NSAIDs), including sulindac. We report the synthesis and characterization of two sulindac analogs, K-8008 and K-8012, which exert improved anticancer activities over sulindac in a RXRα-dependent manner. The analogs inhibit the interaction of the N-terminally truncated RXRα (tRXRα) with the p85α subunit of PI3K, leading to suppression of AKT activation and induction of apoptosis. Crystal structures of the RXRα ligand-binding domain (LBD) with K-8008 or K-8012 reveal that both compounds bind to tetrameric RXRα LBD at a site different from the classical ligand-binding pocket. Thus, these results identify K-8008 and K-8012 as tRXRα modulators and define a binding mechanism for regulating the nongenomic action of tRXRα.

Topics: Animals; Antineoplastic Agents; Binding Sites; Cell Proliferation; Cell Survival; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; HeLa Cells; Hep G2 Cells; Humans; Mice; Mice, Inbred BALB C; Mice, Nude; Models, Molecular; Molecular Structure; Neoplasms; Retinoid X Receptor alpha; Structure-Activity Relationship; Sulindac; Tumor Cells, Cultured

Sulindac is a prescription-based non-steroidal anti-inflammatory drug (NSAID) that continues to be actively investigated as a candidate cancer chemoprevention agent. To further current understanding of sulindac bioavailability, metabolism, and disposition, we developed a population pharmacokinetic model for the parent compound and its active metabolites, sulindac sulfide, and exisulind. This analysis was based on data from 24 healthy subjects who participated in a bioequivalence study comparing two formulations of sulindac. The complex disposition of sulindac and its metabolites was described by a seven-compartment model featuring enterohepatic recirculation and is the first reported population pharmacokinetic model for sulindac. The derived model was used to explore effects of clinical variables on sulindac pharmacokinetics and revealed that body weight, creatinine clearance, and gender were significantly correlated with pharmacokinetic parameters. Moreover, the model quantifies the relative bioavailability of the sulindac formulations and illustrates the utility of population pharmacokinetics in bioequivalence assessment. This novel population pharmacokinetic model provides new insights regarding the factors that may affect the pharmacokinetics of sulindac and the exisulind and sulindac sulfide metabolites in generally healthy subjects, which have implications for future chemoprevention trial design for this widely available agent.

Topics: Adult; Anti-Inflammatory Agents, Non-Steroidal; Antineoplastic Agents; Biological Availability; Capsules; Cross-Over Studies; Female; Humans; Male; Models, Biological; Neoplasms; Sulindac; Tablets

Non-steroidal anti-inflammatory drugs (NSAIDs) have been widely reported to display strong efficacy for cancer chemoprevention, although their mechanism of action is poorly understood. The most well-documented effects of NSAIDs include inhibition of tumor cell proliferation and induction of apoptosis, but their effect on tumor cell invasion has not been well studied. Here, we show that the NSAID, sulindac sulfide (SS) can potently inhibit the invasion of human MDA-MB-231 breast and HCT116 colon tumor cells in vitro at concentrations less than those required to inhibit tumor cell growth. To study the molecular basis for this activity, we investigated the involvement of microRNA (miRNA). A total of 132 miRNAs were found to be altered in response to SS treatment, including miR-10b, miR-17, miR-21 and miR-9, which have been previously implicated in tumor invasion and metastasis. We confirmed that these miRNA can stimulate tumor cell invasion and show that SS can attenuate their invasive effects by downregulating their expression. Employing luciferase and chromatin immunoprecipitation assays, NF-κB was found to bind the promoters of all four miRNAs to suppress their expression at the transcriptional level. We show that SS can inhibit the translocation of NF-κB to the nucleus by decreasing the phosphorylation of IKKβ and IκB. Analysis of the promoter sequences of the miRNAs suppressed by SS revealed that 81 of 115 sequences contained NF-κB-binding sites. These results show that SS can inhibit tumor cell invasion by suppressing NF-κB-mediated transcription of miRNAs.

Topics: Anti-Inflammatory Agents, Non-Steroidal; Cell Line, Tumor; Humans; MicroRNAs; Neoplasm Invasiveness; Neoplasms; NF-kappa B; Sulindac; Transcription, Genetic

Nonsteroidal anti-inflammatory drugs (NSAID) exhibit antineoplastic properties, but conventional NSAIDs do not fully meet safety and efficacy criteria for use as anticancer agents. In this study, we evaluated the chemotherapeutic efficacy of 5 novel phospho-NSAIDs, each of which includes in addition to the NSAID moiety a diethylphosphate linked through a butane moiety. All 5 compounds inhibited the growth of human breast, colon, and pancreatic cancer cell lines with micromolar potency. In vivo investigations confirmed the antitumor activity of phospho-aspirin (PA) and phospho-sulindac (PS) in inhibiting tumor growth in established human xenograft models, in which cell proliferation was suppressed and apoptosis enhanced in the absence of detectable animal toxicity. Notably, all of the phospho-NSAIDs tested induced reactive oxygen and nitrogen species in cultured cells, with PA and PS inducing detectable levels of oxidative stress in vivo that were associated positively with apoptosis and negatively with proliferation. Potentially explaining these effects, all of the phospho-NSAIDs tested also inhibited the thioredoxin system and the redox sensitive transcription factor NF-κB. Taken together, our findings show the strong anticancer efficacy and promising safety of phospho-NSAIDs in preclinical models of breast, colon, and pancreatic cancer, suggesting further evaluation as anticancer agents.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Apoptosis; Aspirin; Cell Line, Tumor; Cell Proliferation; Dose-Response Relationship, Drug; Female; HT29 Cells; Humans; Immunoblotting; Immunohistochemistry; Mice; Mice, Inbred BALB C; Mice, Nude; Molecular Structure; Neoplasms; NF-kappa B; Organophosphates; Sulindac; Thioredoxin-Disulfide Reductase; Thioredoxins; Time Factors; Xenograft Model Antitumor Assays

Nonsteroidal anti-inflammatory drugs (NSAIDs) exert their anticancer effects through cyclooxygenase-2 (COX-2)-dependent and independent mechanisms. Here, we report that Sulindac, an NSAID, induces apoptosis by binding to retinoid X receptor-alpha (RXRalpha). We identified an N-terminally truncated RXRalpha (tRXRalpha) in several cancer cell lines and primary tumors, which interacted with the p85alpha subunit of phosphatidylinositol-3-OH kinase (PI3K). Tumor necrosis factor-alpha (TNFalpha) promoted tRXRalpha interaction with the p85alpha, activating PI3K/AKT signaling. When combined with TNFalpha, Sulindac inhibited TNFalpha-induced tRXRalpha/p85alpha interaction, leading to activation of the death receptor-mediated apoptotic pathway. We designed and synthesized a Sulindac analog K-80003, which has increased affinity to RXRalpha but lacks COX inhibitory activity. K-80003 displayed enhanced efficacy in inhibiting tRXRalpha-dependent AKT activation and tRXRalpha tumor growth in animals.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Apoptosis; bcl-2-Associated X Protein; Cell Line; Cell Line, Tumor; Cell Proliferation; Cell Survival; Cytoplasm; Dinoprostone; Drug Design; Humans; Mice; Mice, Inbred BALB C; Mice, Nude; Models, Molecular; Neoplasms; Phosphatidylinositol 3-Kinases; Prostaglandin-Endoperoxide Synthases; Protein Binding; Protein Processing, Post-Translational; Proto-Oncogene Proteins c-akt; Retinoid X Receptor alpha; Sequence Deletion; Signal Transduction; Sulindac; Transcriptional Activation; Transfection; Tretinoin; Tumor Necrosis Factor-alpha; Xenograft Model Antitumor Assays

To evaluate the safety, pharmacokinetics and determine the recommended dose of the selective apoptotic antineoplastic drug, OSI-461 administered on a twice-daily regimen to patients with advanced solid malignancies.. In this phase I trial, 33 patients were treated with OSI-461 doses ranging from 400 to 1,200 mg given twice daily in 4-week cycles. Pharmacokinetic studies were performed to characterize the plasma disposition of OSI-461 and the effect of food intake on OSI-461 absorption. Secondary biomarker studies were performed to assess the biologic activity of OSI-461 including the measurement of pGSK-3beta, a PKG substrate, and pharmacogenetic studies to identify polymorphisms of CYP3A that influence drug metabolism and of ABCG2, involved in drug resistance.. Thirty-three patients were treated with 86 courses of OSI-461. The dose-limiting toxicities were grade 3 abdominal pain, found in one patient at the 1,000 mg BID fed dose level and all patients at the 1,200 mg BID fed dose level. There was also one episode each of grade 3 fatigue and grade 3 constipation at the 1,000 and 1,200 mg BID fed dose levels, respectively. Other common toxicities included mild to moderate fatigue, nausea, anorexia and mild elevation in bilirubin. Pharmacokinetic studies of OSI-461 revealed approximately a twofold increase in AUC(0-24) when OSI-461 was administered with food. An increase in pGSK-3beta post-dose was seen in the majority of patients and was greater at higher dose levels. No patients exhibited CYP3A4 polymorphisms, while 100% of patients were found to have the CYP3A5*3/CYP3A5*3 polymorphism. Two known polymorphisms of the ABCG2 gene, G34 --> A34 and C421 --> A421, occurred at frequencies of 11.76 and 29%, respectively.. Toxicity and pharmacodynamic data show that the recommended oral dose of OSI-461 is 800 mg twice daily administered with food. The drug appears to be well-tolerated, and overall bioavailability appears to be markedly increased when the drug is administered with food. These results support further disease-directed evaluations of OSI-461 at a dose of 800 mg BID in combination with other chemotherapeutic agents.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Agents; Apoptosis; Area Under Curve; Biomarkers, Tumor; Chromatography, High Pressure Liquid; Cohort Studies; Fasting; Female; Food; Glycogen Synthase Kinase 3; Glycogen Synthase Kinase 3 beta; Humans; Male; Middle Aged; Neoplasms; Pharmacogenetics; Reference Standards; Sulindac; Tandem Mass Spectrometry

Sulindac is an FDA-approved non-steroidal anti-inflammatory drug (NSAID) that affects prostaglandin production by inhibiting cyclooxygenases (COX) 1 and 2. Sulindac has also been of interest for more than decade as a chemopreventive for adenomatous colorectal polyps and colon cancer.. Pretreatment of human colon and lung cancer cells with sulindac enhances killing by an oxidizing agent such as tert-butyl hydroperoxide (TBHP) or hydrogen peroxide. This effect does not involve cyclooxygenase (COX) inhibition. However, under the conditions used, there is a significant increase in reactive oxygen species (ROS) within the cancer cells and a loss of mitochondrial membrane potential, suggesting that cell death is due to apoptosis, which was confirmed by Tunel assay. In contrast, this enhanced killing was not observed with normal lung or colon cells.. These results indicate that normal and cancer cells handle oxidative stress in different ways and sulindac can enhance this difference. The combination of sulindac and an oxidizing agent could have therapeutic value.

Topics: Anti-Inflammatory Agents, Non-Steroidal; Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Cell Survival; Cyclooxygenase Inhibitors; Humans; Membrane Potentials; Mitochondria; Neoplasms; Oxidative Stress; Reactive Oxygen Species; Sulindac

Nonsteroidal anti-inflammatory drugs (NSAID) are effective in suppressing the formation of colorectal tumors. However, the mechanisms underlying the antineoplastic effects of NSAIDs remain unclear. The effects of NSAIDs are incomplete, and resistance to NSAIDs is often developed. Growing evidence has indicated that the chemopreventive activity of NSAIDs is mediated by induction of apoptosis. Our previous studies showed that second mitochondria-derived activator of caspase (SMAC)/Diablo, a mitochondrial apoptogenic protein, plays an essential role in NSAID-induced apoptosis in colon cancer cells. In this study, we found that SMAC mediates NSAID-induced apoptosis through a feedback amplification mechanism involving interactions with inhibitor of apoptosis proteins, activation of caspase-3, and induction of cytosolic release of cytochrome c. Small-molecule SMAC mimetics at nanomolar concentrations significantly sensitize colon cancer cells to NSAID-induced apoptosis by promoting caspase-3 activation and cytochrome c release. Furthermore, SMAC mimetics overcome NSAID resistance in Bax-deficient or SMAC-deficient colon cancer cells by restoring caspase-3 activation and cytochrome c release. Together, these results suggest that SMAC is useful as a target for the development of more effective chemopreventive strategies and agents.

Topics: Anti-Inflammatory Agents, Non-Steroidal; Apoptosis; Apoptosis Regulatory Proteins; bcl-2-Associated X Protein; Biomimetic Materials; Caspase 3; Chemoprevention; Cytochromes c; Humans; Intracellular Signaling Peptides and Proteins; Mitochondrial Proteins; Neoplasms; Sulindac; Tumor Cells, Cultured

The identification of self-renewing and multipotent neural stem cells (NSCs) in the mammalian brain holds promise for the treatment of neurological diseases and has yielded new insight into brain cancer. However, the complete repertoire of signaling pathways that governs the proliferation and self-renewal of NSCs, which we refer to as the 'ground state', remains largely uncharacterized. Although the candidate gene approach has uncovered vital pathways in NSC biology, so far only a few highly studied pathways have been investigated. Based on the intimate relationship between NSC self-renewal and neurosphere proliferation, we undertook a chemical genetic screen for inhibitors of neurosphere proliferation in order to probe the operational circuitry of the NSC. The screen recovered small molecules known to affect neurotransmission pathways previously thought to operate primarily in the mature central nervous system; these compounds also had potent inhibitory effects on cultures enriched for brain cancer stem cells. These results suggest that clinically approved neuromodulators may remodel the mature central nervous system and find application in the treatment of brain cancer.

Topics: Animals; Cell Survival; Cells, Cultured; Mice; Molecular Structure; Neoplasms; Neurons; Pharmaceutical Preparations; Sensitivity and Specificity; Stem Cells

A review of almost 2000 studies showed that the large majority of 39 putative cancer chemopreventive agents induced "spontaneous" apoptosis. Inhibition of the programmed cell death triggered by a variety of stimuli was consistently reported only with ascorbic acid, alpha-tocopherol, and N-acetylcysteine (NAC). We performed experimental studies in rodents exposed to cigarette smoke, either mainstream (MCS) or environmental (ECS), and UV-A/B-containing light. The nonsteroidal anti-inflammatory drug sulindac did not affect the apoptotic process in the skin of light-exposed mice and in the lungs of ECS-exposed mice. Likewise, 5,6-benzoflavone, indole-3-carbinol, 1,2-dithiole-3-thione and oltipraz failed to modulate apoptosis in the respiratory tract of ECS-exposed rats. Phenethyl isothiocyanate further enhanced the frequency of apoptosis in pulmonary alveolar macrophages and bronchial epithelial cells, and upregulated several genes in the lung of ECS-exposed rats. Both individually and in combination with oltipraz, NAC inhibited apoptosis in the respiratory tract of rats exposed either to MCS or ECS. Moreover, NAC attenuated the ECS-related overexpression of proapoptotic genes and normalized the levels of proapoptotic proteins in rat lung. The transplacental administration of NAC to mice considerably attenuated gene overexpression in the liver of fetuses exposed to ECS throughout pregnancy. Inhibition of apoptosis by chemopreventive agents reflects their ability to counteract certain upstream signals, such as genotoxic damage, redox imbalances, and other forms of cellular stress that trigger apoptosis. On the other hand, enhancement of apoptosis is a double-edged sword, since it represents a protective mechanism in carcinogenesis but may contribute to the pathogenesis of other degenerative diseases. We suggest that stimulation of apoptosis by so many chemopreventive agents, as reported in the literature, may often reflect the occurrence of toxic effects at high doses.

Topics: Animals; Anticarcinogenic Agents; Antineoplastic Agents; Apoptosis; Epithelium; Female; Gene Expression Profiling; Humans; In Situ Nick-End Labeling; Light; Male; Mice; Mice, Nude; Molecular Sequence Data; Neoplasms; Nicotiana; Oligonucleotide Array Sequence Analysis; Pregnancy; Rats; Rats, Sprague-Dawley; Respiratory System; Smoke; Sulindac

Human esophageal adenocarcinoma (EAC) develops in a sequence from gastroesophageal reflux disease (GERD), columnar-lined esophagus (CLE), dysplasia, and eventually to EAC. We established a rat surgical EAC model with esophagogastroduodenal anastomosis (EGDA) to mimic the staged process of esophageal adenocarcinogenesis. Profiling of the AA metabolites with mass spectrometry showed that prostaglandin E2 (PGE2), leukotriene B4 (LTB4), 15-hydroeicosatetraenoic acid (HETE), 12-HETE, 8-HETE and 5-HETE all increased at the esophagoduodenal junction after EGDA as compared with the proximal esophagus, with PGE2 as the major metabolite. Consistent with this profile, cyclooxygenase 2 (Cox2) was overexpressed in the basal cell layer of esophageal squamous epithelium, CLE cells and EAC tumor cells of the EGDA rats, as compared with the normal esophageal epithelium. Sulindac (a Cox inhibitor), nordihydroguaiaretic acid (NDGA, a lipoxygenase inhibitor) and alpha-difluoromethylornithine (DFMO, an ornithine decarboxylase inhibitor) were tested for their possible inhibitory actions against the formation of EAC in the rat EGDA model. In a short-term study (for 4 weeks after surgery), dietary administration of both sulindac (300 and 600 p.p.m.) and NDGA (100 p.p.m.) effectively reduced the EGDA-induced inflammation. In a long-term chemoprevention study (for 40 weeks after surgery), 300 p.p.m. sulindac, alone or in combination with 100 p.p.m. NDGA or 0.5% DFMO, decreased the tumor incidence from 57.7 to 26.9%, or 16.7 or 20%, respectively (P < 0.05). NDGA alone (100 and 200 p.p.m.) slightly decreased the tumor incidence to 52.4 and 37%, respectively, although the difference was not statistically significant. DFMO alone did not show significant effects on tumor incidence. Inhibition of tumor formation by sulindac was correlated with lowered levels of PGE2. In conclusion, sulindac exerted its chemopreventive effect against the formation of EAC in the rat EGDA model possibly through its inhibition of Cox.

Topics: 12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; Animals; Arachidonic Acid; Body Weight; Cyclooxygenase 2; Dinoprostone; Eflornithine; Esophageal Neoplasms; Esophagus; Gas Chromatography-Mass Spectrometry; Hydroxyeicosatetraenoic Acids; Immunoenzyme Techniques; In Situ Hybridization; Inflammation; Isoenzymes; Leukotriene B4; Male; Masoprocol; Mass Spectrometry; Neoplasms; Prostaglandin-Endoperoxide Synthases; Rats; Rats, Sprague-Dawley; Sulindac; Time Factors

As part of our screening program for cancer inhibitory agents effective specifically in the promotion stage of cancer development, we have evaluated the possible inhibitory effects of 36 non-steroidal anti-inflammatory drugs (NSAIDs) on the Epstein-Barr virus early antigen (EBV-EA) activation which was induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells. All the drugs were observed to inhibit the EBV-EA activation at low doses with low toxicity. The two most active anti-tumor promoting agents were the arylacetic acid derivatives, etodolac and sulindac. We also report for the first time the activities of 14 new NSAIDs belonging to different classes as potential cancer chemopreventive agents. A structure-activity relationship study showed that among the salicylic acid derivative tested, the oxidation of the thiol group to dithiol derivatives results in the reduction of the activity. Introduction of amino group on the salicylic acid molecules also results in the reduction of activity in the EBV-EA assay. The results are of great interest in the development of NSAIDs as cancer chemopreventive agents, which halt cancer progression in multistage carcinogenesis, where successive activities are required to evolve into fully-fledged and metastatic cancer.

Topics: Acetates; Anti-Inflammatory Agents, Non-Steroidal; Antigens, Viral; Benzene; Carcinogens; Carcinoma; Cell Survival; Etodolac; Fluorescent Antibody Technique, Indirect; Humans; Nasopharyngeal Neoplasms; Neoplasms; Oxidation-Reduction; Salicylates; Structure-Activity Relationship; Sulindac; Tetradecanoylphorbol Acetate; Tumor Cells, Cultured

Worldwide interest in green tea as a cancer preventive agent for humans has increased, because it is non-toxic and it is effective in a wide range of organs. (-)-Epigallocatechin gallate (EGCG) is the main constituent of green tea; the others are (-)-epicatechin gallate, (-)-epigallocatechin and (-)-epicatechin (EC). This paper reports the results of our latest pharmacological and biochemical studies with 3H-EGCG, along with studies on human subjects. The study on bioavailability of 3H-EGCG in mice revealed the wide distribution of radioactivity in multiple organs. Specifically, radioactivity was found in all reported target organs of EGCG and green tea extract (digestive tract, liver, lung, pancreas, mammary gland and skin) as well as other organs (brain, kidney, uterus and ovary or testes) in mice. Recently, we demonstrated that EC enhanced incorporation of 3H-EGCG into human lung cancer cell line PC-9 cells. EC along with another cancer preventive agent sulindac also synergistically enhanced apoptosis in PC-9 cells induced by EGCG. Moreover, a case-control study on breast cancer patients revealed that high daily consumption of green tea was associated with a lower recurrence rate among Stages I and II patients. All the results suggest that consumption of green tea is a practical and effective cancer preventive both before cancer onset and after cancer treatment.

Topics: 3T3 Cells; Animals; Apoptosis; Biological Availability; Breast Neoplasms; Case-Control Studies; Catechin; Drug Synergism; Female; Humans; Japan; Male; Mice; Neoplasms; Sulindac; Tea; Tissue Distribution; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha

Cancer chemoprevention is a new and important medical science in its own right. On the occasion of my presentation entitled "Natural agents and cancer chemoprevention" at the 90th AACR Meeting in 1999, I summarized our recent results on cancer prevention with green tea. In this article, the present status of clinical trials supported by the Chemoprevention Branch of the National Cancer Institute in the United States is first described by way of introduction. Although various natural products are now under investigation in phase I clinical trials, green tea has, perhaps, the greatest potential for further development. In order to expand our understanding of the effects of tea polyphenols and green tea, I review their ability to inhibit growth and cause apoptosis of cancer cells, their distribution into target organs and their other cancer-preventing properties. In addition, the paper focuses on the significance of reducing tumor necrosis factor alpha (TNFalpha) gene expression in cells and TNFalpha release from cells as essential activities for cancer prevention. As for the amounts of green tea effective in cancer prevention, I present two results from our Research Institute: a prospective cohort study with over 8000 individuals in Saitama Prefecture revealed that the daily consumption of at least ten Japanese-size cups of green tea resulted in delayed cancer onset, and a follow-up study of breast cancer patients conducted at our Hospital found that stages I and II breast cancer patients consuming over five cups per day experienced a lower recurrence rate and longer disease-free period than those consuming fewer than four cups per day. Thus, I propose here, for the first time, the two-stage approach to analyzing cancer prevention with green tea: cancer prevention before cancer onset and cancer prevention following cancer treatment. As an additional example of cancer prevention with natural agents, kava, a daily beverage in Fiji, is mentioned. All the evidence reminds us of the significance of alternative medicine in practical cancer prevention.

Topics: Adult; Aged; Anti-Inflammatory Agents, Non-Steroidal; Anticarcinogenic Agents; Apoptosis; Catechin; Cell Division; Cohort Studies; Drug Synergism; Female; Humans; Kava; Male; Neoplasms; Phytotherapy; Plants, Medicinal; Prospective Studies; Sulindac; Tea; Tissue Distribution; Tumor Necrosis Factor-alpha

Topics: Animals; Anticarcinogenic Agents; Clinical Trials as Topic; Drug Approval; Female; Humans; Male; Neoplasms; Neoplasms, Experimental; Rats; Research Design; Sulindac