Use of NSAIDs for the Chemoprevention of Colorectal Cancer

Which Drugs are More Effective in Preventing Familial Adenomatous Polyposis Progression based on Network Meta-analysis?

BACKGROUND

Familial adenomatous polyposis (FAP) is an inherited disorder. At present, an increasing number of medications are being employed to treat FAP; however, only a few have been assessed for their efficacy and safety. Therefore, this study aimed to conduct a network meta-analysis to compare the therapeutic outcomes and adverse drug reactions of all FAP-associated medications.

METHODS

Six relevant databases were searched to identify pertinent randomized controlled trials (RCTs), and information on the dosage and frequency of various drugs was extracted. Additionally, data on changes in polyp counts and dimensions, as well as treatment-related adverse reactions for different medications were collected. The Bayesian method was employed to directly or indirectly compare the impact of different treatment regimens on changes in polyp numbers and diameters, and the safety of the drugs was investigated.

RESULTS

CXB at 16 mg/kg/day significantly reduced polyp numbers. Celecoxib at 8 mg/kg/day and sulindac (150 mg twice daily) plus erlotinib (75 mg/day) were effective for tolerant FAP patients. Additionally, EPAFFA 2 g daily and sulindac (150 mg twice daily) plus erlotinib (75 mg/day) emerged as the most effective for reducing polyp size.

CONCLUSION

The most effective treatment for reducing the number of colorectal polyps is celecoxib 16 mg/kg/day. On the other hand, a daily dosage of 2 g EPA-FFA demonstrates the best results in terms of decreasing colorectal polyp diameter.

Crystal Structure and Chemical Bonds in [CuII2(Tolf)4(MeOH)2]∙2MeOH

A new coordination compound of copper(II) with a tolfenamate ligand of the paddle-wheel-like structure [Cu^II₂(Tolf)₄(MeOH)₂]∙2MeOH was obtained and structurally characterized. Chemical bonds of Cu(II)∙∙∙Cu(II) and Cu(II)-O were theoretically analyzed and compared with the results for selected similar structures from the CSD database. QTAIM analysis showed that the Cu(II)∙∙∙Cu(II) interaction has a strength comparable to a hydrogen bond, as indicated by the electron density at a critical point. The remaining QTAIM parameters indicate stability of the Cu(II)∙∙∙Cu(II) interaction. Other methods, such as NCI and NBO, also indicate a significant strength of this interaction. Thus, the Cu(II)∙∙∙Cu(II) interaction can be treated as one of the noncovalent interactions that affects the structure of the coordination compound, the packing of molecules in the crystal, and the general properties of the compound.

Hyaluronic acid-doxorubicin nanoparticles for targeted treatment of colorectal cancer

Colorectal cancer, common in both men and women, occurs when tumors form in the linings of the colon. Common treatments of colorectal cancer include surgery, chemotherapy, and radiation therapy; however, many colorectal cancer treatments often damage healthy tissues and cells, inducing severe side effects. Conventional chemotherapeutic agents such as doxorubicin (Dox) can be potentially used for the treatment of colorectal cancer; however, they suffer from limited targeting and lack of selectivity. Here, we report that doxorubicin complexed to hyaluronic acid (HA) (HA-Dox) exhibits an unusual behavior of high accumulation in the intestines for at least 24 hr when injected intravenously. Intravenous administrations of HA-Dox effectively preserved the mucosal epithelial intestinal integrity in a chemical induced colon cancer model in mice. Moreover, treatment with HA-Dox decreased the expression of intestinal apoptotic and inflammatory markers. The results suggest that HA-Dox could effectively inhibit the development of colorectal cancer in a safe manner, which potentially be used a promising therapeutic option.

Insight into the Colonic Disposition of Sulindac in Humans

NSAIDs such as celecoxib and sulindac play a critical role in the treatment of colorectal cancer, yet it is not understood how sufficiently high concentrations are reached in colonic tissue. We previously demonstrated that an incomplete small intestinal absorption of celecoxib enables gut driven drug accumulation in caecal tissue, which is most likely needed for inducing remission. However, a multistage dissolution experiment suggested a more extensive absorption of sulindac relative to celecoxib, though still incomplete. To study whether caecal accumulation of sulindac is solely plasma driven or also gut driven, we performed an exploratory clinical study in healthy volunteers. After intake of a tablet of sulindac (200 mg; Arthrocine), two colonoscopies (1.0-2.5 h, and 6.0-7.5 h after drug intake) were performed to assess concentrations of sulindac and metabolites in plasma, caecal tissue and caecal contents. We observed that sulindac, even without the use of a colon-targeted delivery strategy, can arrive at the colonic lumen due to incomplete absorption and biliary excretion, and that the microbiota can catalyse the production of sulindac sulfide, which then accumulates in a high and local manner in the colonic tissue. These data can be relevant for drug development in the treatment of colorectal adenomas and cancer.

Quasi-Isostructural Co(II) and Ni(II) Complexes with Mefenamato Ligand: Synthesis, Characterization, and Biological Activity

Three metal complexes of mefenamato ligand 1 were synthesized: [Co2(mef)4(EtOH)2(H2O)4]: 2; [Co(mef)2(MeOH)4]∙2MeOH: 3; and [Ni(mef)2(MeOH)4]∙2MeOH: 4. Their compositions and properties were investigated by elemental analysis (EA), flame atomic absorption spectrometry (FAAS), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Crystal structures were determined by the single crystal X-ray diffraction technique. Additionally, their antioxidant and antimicrobial activity were established, thus proving good/moderate bioactivity against Gram-positive bacteria and yeasts. In the crystal structure of 2, an apical water molecule is shared between two adjacent cobalt(II) ions, resulting in the formation of a polymeric chain extending along the [100] direction. Meanwhile, structures 3 and 4 have strong intermolecular hydrogen bonds with diverse topologies that yield unique quasi-isostructural arrangements. The packing topology is reflected by the Hirshfeld surface analysis of intermolecular contacts.

Insight into the colonic disposition of celecoxib in humans

Although the effect of NSAIDs such as celecoxib on the progression of colorectal polyps has been established, it is currently unknown how sufficiently high concentrations of celecoxib are reached in colonic tissue. Indeed, the lipophilic and poorly soluble celecoxib is orally dosed as an immediate release capsule without any colon-targeting delivery strategy. In the present study, we aimed to distinguish between plasma and gut driven caecal tissue accumulation of celecoxib in healthy volunteers. After developing a protocol to reliably collect colonic biopsies and contents, the disposition of celecoxib was assessed in plasma, caecal tissue and caecal contents collected after intake of a celecoxib capsule (200 mg; Celebrex®) with 240 mL of tap water. During a first colonoscopy (1.0-2.5 h after drug intake), plasma concentrations of celecoxib and its carboxy metabolite were increasing, while caecal tissue concentrations were relatively low. As no celecoxib was present in caecal contents, tissue accumulation was clearly plasma driven. During a second colonoscopy (6.0-7.5 h after drug intake), tissue concentrations of the drug and its metabolite were substantially higher despite decreasing plasma concentrations. As a high amount of celecoxib was found in the caecal contents, the increased tissue accumulation most likely resulted from direct uptake of celecoxib from the gut. These data demonstrate that incomplete small intestinal absorption of the poorly soluble drug celecoxib enables gut driven drug accumulation in caecal tissue, which is, most likely, critical for the role of this NSAID in the prevention of colorectal cancer.

Synthesis, toxicity and antitumor activity of cobalt carbonyl complexes targeting hepatocellular carcinoma

Based on our previous research, a series of targeting hepatocellular carcinoma complexes, [R-Glycyrrhetinic acid-CH₂C₂H-[Co₂(CO)₆] (R = H, 1; R = NSAIDs-COOH, 2-4; R = Aromatic acid, 5-7; R = Amino acid, 8-10), were synthesized. The test showed they are slow CO releasers. Using HeLa, A549, HT-29, SMMC7721 and HepG2 cells as models, their activities against tumor cell proliferation were firstly evaluated. The resulting data show all the complexes displayed a good anti-proliferation activity against the HepG2 and SMMC-7721 liver cancer cells, and their IC₅₀ values were in the range of 10.07-66.06 µM; compared with cis-platin (DDP), their activities were comparable or even better under the same condition. Among them, complexes 3, 4, 6 and 9 exhibited higher anti-proliferation activities against HepG2 and SMMC-7721 cell lines than the other cell lines. To confirm further these complexes have selectivity to the liver cells, the uptakes of complexes 3, 4, 6 and 9 by HepG2, HT-29, A549 and SMMC7721 cell lines were studied. The results show the cell uptake rates of the complexes by HepG2 cells and SMMC7721 cells were much greater than by other cells under the same condition. In following tests, the tested complexes displayed higher activities in inhibiting NF-kB, COX-2 and iNOS; and they induced HepG2 cells apoptosis by mitochondrial pathway, which assessed by staining with different fluorescent reagent DAPI, PI, Mito-Tracker Green and DCFH-DA. Meanwhile, the tested complexes up-regulated the expression levels of caspase-3 and Bax, down-regulated the Bcl-2 expression. In addition, they had no effect on zebrafish embryo survival, embryo hatching, embryonic movement, zebrafish malformation and zebrafish movement at below 0.5 µM. This suggests the complexes are potential candidates to be used in clinic for liver cancers.

The Na-O bond in sodium fenamate

The one-dimensional polymeric structure of sodium diaquafenamate-water (1/1) was studied by X-ray diffraction. The sodium cation is coordinated to one oxygen atom of the carboxylate group and to four water oxygen atoms. To characterize the Na-O bonds, the quantum theory of atoms in molecules (QTAIM) and noncovalent interaction (NCI) approaches have been used. Both methods confirmed that the Na-O bonds are very weak, comparable with the weak N-H...O intramolecular hydrogen bond. The polymeric structure is stabilized by the interaction of the sodium cation with the surrounding water molecules.

Non-aspirin non-steroidal anti-inflammatory drugs in prevention of colorectal cancer in people aged 40 or older: A systematic review and meta-analysis

There is still insufficient data about the risk-benefit profile about recommending non-aspirin, non-steroidal anti-inflammatory drugs (NA-NSAIDs) for colorectal cancer (CRC) prevention, especially in people aged 40 years or older. This study specifically addressed the association between regular NA-NSAIDs use and CRC risk in the population aged 40 years or older, performing a comprehensive systematic review and meta-analysis of all published studies on this topic until April 2018, by a search of PubMed, Scopus and Web of science databases and clinical trial registries. Two reviewers independently selected studies based on predefined inclusion criteria and assessed study quality using the Newcastle-Otawa scale. The data was combined with the random effects model. Potential heterogeneity was calculated as Q statistic and I² value. A total of 23 studies involving more than 1 million subjects contributed to the analysis. Pooled odds ratio (OR) of NA-NSAIDs effects on CRC risk was 0.74 (0.67-0.81), I² = 75.9%, p < 0.001. Heterogeneity was explained by a number of variables including the quality of the studies. Significant protective effects of NA-NSAIDs use were found for women (risk reduction of 19%), higher doses (risk reduction of 18%), distal colon cancer (risk reduction of 22%) and white people (risk reduction from 31% to 41%). From the results NA-NSAIDs use appears to be CRC chemopreventive for a specific subgroup of the population.

Influence of NSAID Use Among Colorectal Cancer Survivors on Cancer Outcomes

PURPOSE

Colorectal cancer (CRC) is the third most common cancer diagnosed in men and women in the United States. Given the availability of effective screening, most tumors are found early enough to offer patients substantial long-term survival. Thus there is a resulting significant population of CRC survivors for whom modifiable risk factors for recurrence and survival would be of interest.

METHODS

We conducted a population-based retrospective cohort study among patients enrolled in 2 large Midwestern health plans for which claims data, including pharmacy fill data, and medical record data were available. Men and women who were 40 years of age or older at the time of CRC diagnosis with disease less than stage IV and no history of Crohn disease, ulcerative colitis, and irritable bowel syndrome were included. CRC cases diagnosed between January 1, 1990 and December 31, 2000 were included if they met the inclusion criteria. Adjusted Cox proportional hazard models were used with exposure modeled as a time-dependent covariate. We assessed progression-free survival, defined as an aggressive polyp or invasive disease, and overall survival.

RESULTS

After adjustment for age at diagnosis, sex, race, body mass index, stage, side of initial tumor, and tumor histology, we found that current users of nonsteroidal anti-inflammatory drugs had a 3-fold decreased risk of recurrence and a >7-fold decreased risk of death. Our results are statistically significant with P-values <0.05.

CONCLUSIONS

Our results suggest that current use of nonsteroidal anti-inflammatory drugs provides significant improvements in CRC outcomes.

Hereditary Colorectal Cancer Syndromes

Awareness of hereditary colorectal cancer syndromes is important to facilitate their identification because affected patients are at increased risk for early onset, synchronous, and metachronous colorectal malignancies, and certain extracolonic malignancies depending on the syndrome. Identification of an affected individual allows for screening and early interventions for patients and their at-risk kindred. Genetic counseling and testing is important to the care of these patients. As knowledge of the genetic basis of these syndromes grows, unique genotype-phenotype profiles allow clinicians to tailor surveillance and treatment strategies based on individual risk.

Celecoxib coupled to dextran via a glutamic acid linker yields a polymeric prodrug suitable for colonic delivery

Celecoxib, a selective cyclooxygenase-2 inhibitor, is potentially useful for the treatment of colonic diseases such as colorectal cancer and colitis. However, the cardiovascular toxicity of celecoxib limits its routine use in the clinic. Generally, colon-specific delivery of a drug both increases the therapeutic availability in the large intestine and decreases the systemic absorption of the drug, most likely resulting in enhanced therapeutic effects against colonic diseases such as colitis and reduced systemic side effects. To develop a colon-specific prodrug of celecoxib that could reduce its cardiovascular toxicity and improve its therapeutic activity, dextran–glutamic acid–celecoxib conjugate (glutam-1-yl celecoxib-dextran ester [G1CD]) was prepared and evaluated. While stable in pH 1.2 and 6.8 buffer solutions and small-intestinal contents, G1CD efficiently released celecoxib in cecal contents. Oral administration of G1CD to rats delivered a larger amount of celecoxib to the large intestine than free celecoxib. G1CD prevented the systemic absorption of celecoxib and did not decrease the serum level of 6-ketoprostaglandin F_1α, an inverse indicator of cardiovascular toxicity of celecoxib. Collectively, G1CD may be a polymeric colon-specific celecoxib prodrug with therapeutic and toxicological advantages.

Hypoxia inducible factor-1α: Its role in colorectal carcinogenesis and metastasis

Tumor growth creates a hypoxic microenvironment, which promotes angiogenesis and aggressive tumor growth and invasion. HIF1α is a central molecule involved in mediating these effects of hypoxia. In colorectal cancer (CRC), hypoxia stabilizes the transcription factor HIF1α, leading to the expression of genes that are involved in tumor vascularization, metastasis/migration, cell survival and chemo-resistance. Therefore, HIF1α is a rational target for the development of new therapeutics for CRC. This article reviews the central role of HIF1α in CRC angiogenesis, metastasis, and progression as well as the strategies to target HIF1α stabilization.

Epitheloid hemangioma treated with naproxen sodium

Epitheloid hemangioma (EH) is a vascular tumor characterized by an epithelioid endothelial cell. Predominantly affecting the head and neck, fewer than 30 cases involving the scrotum have been published. As this represents an extremely rare entity, a multitude of anecdotal treatment modalities have been utilized including systemic/intralesional steroid therapy, radiotherapy, and chemical therapy. However, surgical excision remains the most widely accepted treatment option.We present a case of EH of the scrotum in a 14-year-old male patient that regressed after treatment with naproxen sodium. To the best of our knowledge, this represents the first reported case of scrotal EH regression following treatment with naproxen sodium.

LEVEL OF EVIDENCE

V.

Repurposing the FDA-approved pinworm drug pyrvinium as a novel chemotherapeutic agent for intestinal polyposis

Mutations in the WNT-pathway regulator ADENOMATOUS POLYPOSIS COLI (APC) promote aberrant activation of the WNT pathway that is responsible for APC-associated diseases such as Familial Adenomatous Polyposis (FAP) and 85% of spontaneous colorectal cancers (CRC). FAP is characterized by multiple intestinal adenomas, which inexorably result in CRC. Surprisingly, given their common occurrence, there are few effective chemotherapeutic drugs for FAP. Here we show that the FDA-approved, anti-helminthic drug Pyrvinium attenuates the growth of WNT-dependent CRC cells and does so via activation of CK1α. Furthermore, we show that Pyrvinium can function as an in vivo inhibitor of WNT-signaling and polyposis in a mouse model of FAP: APC^min mice. Oral administration of Pyrvinium, a CK1α agonist, attenuated the levels of WNT-driven biomarkers and inhibited adenoma formation in APC^min mice. Considering its well-documented safe use for treating enterobiasis in humans, our findings suggest that Pyrvinium could be repurposed for the clinical treatment of APC-associated polyposes.

Antidepressant drugs as a complementary therapeutic strategy in cancer

In the last decade, it has been increasingly recognized that antidepressant drugs may exert a range of effects, in addition to their well-documented ability to modulate neurotransmission. Although as a group they act on monoaminergic systems and receptors in different ways, a number of studies have demonstrated that at least some antidepressants might have other properties in common, including immunomodulatory, cyto/neuroprotective, analgesic and anti-inflammatory activities. These properties are partly related to the influence of antidepressants on glial cell function. Recently, emerging information about the possible anticancer properties of antidepressants has sparked increased interest within scientific community, and there is now evidence that these drugs affect the key cellular mechanisms of carcinogenesis. This review examines the putative cellular targets for the anticancer action of antidepressant drugs, and presents examples of the interaction between antidepressants and anticancer drugs. By reviewing the current state of research in this area, we hope to focus the attention of oncologists and researchers engaged in the study of cancer on the role that antidepressant drugs could play in the complementary therapy of cancer.

Prevalence and distribution of adenomas in black Americans undergoing colorectal cancer screening

BACKGROUND

The American College of Gastroenterology recommends colorectal cancer (CRC) screening for average-risk black Americans ages 45-49. This is based on this group's younger age for the development of adenomas and CRC. Our purpose was to determine the yield of CRC screening in average-risk black Americans including those <age 50. We also aimed to identify whether there was a higher prevalence of proximal adenomas in black Americans.

STUDY

This was a cross-sectional, retrospective study. All colonoscopy examinations from 2007 through 2010 were reviewed. Complete examinations with a good/excellent preparation in average-risk black patients 45-49 were selected. We excluded patients with signs, symptoms, or family history of CRC. Defined two control groups: average-risk black and white patients ages 50-59 who completed a colonoscopy during the same period. Patient's height, weight, and use of statin medications and aspirin were recorded. Patients currently using tobacco at least weekly were identified.

RESULTS

There were 1,230 patients with an adenoma for a prevalence of 40.7%. We included 304 black Americans 45-49 years, 669 black Americans 50-59 years, and 257 whites 50-59 years. There was no association between race/age group and the presence of at least one adenoma, proximal adenomas, or advanced adenomas. In regression modeling, both male sex and active smoking were associated with all three outcomes.

CONCLUSIONS

Male sex and active smoking are risk factors for prevalent adenomas, proximal adenomas, and advanced adenomas. The prevalence of adenomas is similar in black Americans 45-49 compared to older black and white patients. We did not find that the recognized proximal distribution of CRC in black Americans parallels a similar distribution in adenomas in this group.

Nonsteroidal anti-inflammatory drug use and risk of adenomatous and hyperplastic polyps

Adenomatous polyps are known precursor lesions for colorectal cancer and some hyperplastic polyps also have malignant potential. The use of aspirin and nonsteroidal anti-inflammatory drugs (NSAID) is associated with a reduced risk of adenomatous polyps; however, less evidence exists with regard to NSAID use and hyperplastic polyp risk. We conducted a colonoscopy-based case-control study including 2,028 polyp cases (1,529 adenomatous and 499 hyperplastic) and 3,431 polyp-free controls. Multivariate logistic regression models were constructed to derived adjusted ORs and 95% CIs as the measure of the association between NSAID use and polyp risk. Use of baby aspirin, regular aspirin, and nonaspirin NSAIDs, were associated with a reduced risk of adenomatous polyps (OR = 0.79, 95% CI: 0.66-0.93, OR = 0.73, 95% CI: 0.58-0.90, and OR = 0.67, 95% CI: 0.53-0.86, respectively). Baby aspirin was also associated with a reduced risk of hyperplastic polyps (OR = 0.74, 0.56-0.97). Although a dose response was seen with adenoma risk and regular use of any NSAIDs (less than 7 doses per week, 7 doses per week, and greater than 7 doses per week), a dose response was not seen with hyperplastic polyps. We found no evidence of interaction between NSAID dose and duration and polyp risk. The use of any NSAID regardless of type was associated with a reduced risk of adenomatous polyps; however, regular aspirin and COX-2 inhibitors use was not associated with hyperplastic polyp risk.

The American College of Gastroenterology Emily Couric Lecture--the adenoma-carcinoma sequence revisited: has the era of genetic tailoring finally arrived?

Colorectal cancer (CRC) remains a common and often lethal disease. The classic adenoma-carcinoma sequence was defined on histologic grounds but over the last 25 years, the molecular basis of this process has been progressively clarified. There are at least three distinct molecular pathways to CRC: the chromosomal instability (CIN) pathway is thought to be largely driven by mutational events in oncogenes and tumor suppressor genes, the microsatellite instability pathway is responsible for Lynch syndrome CRCs and is driven by mutations in one of the DNA mismatch repair genes, and the epigenetic pathway is thought to be driven in large part by hypermethylation-induced silencing of tumor suppressor-like genes. The molecular understanding of this sequence has had a profound impact on our understanding of the process(s) of colonic carcinogenesis and this understanding has begun to change the clinical care of patients with colonic polyps and cancer including changes in therapy of established CRCs (anti-epidermal growth factor receptor antibody therapy is no longer offered to patients with mutant KRAS CRCs), identification of high-risk groups (diagnosis of Lynch syndrome by molecular analysis of CRCs) and the management of precursor lesions (identification of the serrated polyp pathway to CRC).

Non-steroidal anti-inflammatory drug use and colorectal polyps in the Prostate, Lung, Colorectal, And Ovarian Cancer Screening Trial

OBJECTIVES

Non-steroidal anti-inflammatory drugs (NSAIDs) have been documented in animal and human studies to reduce risk for colorectal cancer and adenomatous polyps, but risk modification for subgroups of the population and effects on hyperplastic polyps have been less studied.

METHODS

Data on recent use of two frequently ingested NSAIDs, aspirin and ibuprofen, were collected at baseline from participants aged 55-74 years in the 10 centers of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO). Participants randomized to the intervention arm of the trial received a flexible sigmoidoscopy during a baseline examination. Follow-up of detected polyps was accomplished outside the Trial setting and relevant records were sought and abstracted. Cases (n=4,017) included subjects with a biopsy-proven polyp in the left side of the colon (descending colon, sigmoid, and rectum) detected as a consequence of PLCO screening; controls (n=38,396) were subjects with no left-sided colon polyp.

RESULTS

Regular use of aspirin (≥ 4 times/month) in the past year was inversely associated with hyperplastic polyps (odds ratios (OR)=0.8, 95% confidence interval (CI)=0.7-0.9), adenomatous polyps (OR=0.8, 95% CI=0.8-0.9), and advanced adenomas (OR=0.8, 95% CI=0.7-0.9). As frequency of aspirin use increased, the prevalence of polyps decreased significantly for each histological classification (P for trend ≤ 0.0004). Similar patterns were found for adenomas and ibuprofen. Overall protection was consistent in both the descending colon or sigmoid and the rectum, but more evident in males. In males, the OR for heavy use of combined aspirin and ibuprofen (≥ 2 times/day) was 0.6 (95% CI=0.5-0.8), as opposed to 0.9 (95% CI=0.8-1.1) in females. The protective effects of NSAIDs for females were apparent only among those with body mass index (BMI) <25 (OR=0.8, 95% CI=0.7-1.0 for regular use of NSAIDs; P interaction=0.04). We also found a slightly stronger protection of NSAIDs in the 70-74 years age group compared with those aged 55-69 years.

CONCLUSIONS

This study of a large general risk population supports previous work that recent use of aspirin and ibuprofen is associated with a decreased risk of colorectal adenomas and demonstrates that this protective effect may be stronger in certain population subgroups and is also evident for aspirin and hyperplastic polyps.

Does administration of non-steroidal anti-inflammatory drug determine morphological changes in adrenal cortex: ultrastructural studies

Rofecoxib (Vioxx© made by Merck Sharp & Dohme, the USA) is a non-steroidal anti-inflammatory drug which belongs to the group of selective inhibitors of cyclooxygenasis-2, i.e., coxibs. Rofecoxib was first registered in the USA, in May 1999. Since then the drug was received by millions of patients. Drugs of this group were expected to exhibit increased therapeutic action. Additionally, there were expectations concerning possibilities of their application, at least as auxiliary drugs, in neoplastic therapy due to intensifying of apoptosis. In connection with the withdrawal of Vioxx© (rofecoxib) from pharmaceutical market, attempts were made to conduct electron-microscopic evaluation of cortical part of the adrenal gland in preparations obtained from animals under influence of the drug. Every morning animals from the experimental group (15 rats) received rofecoxib (suspension in physiological saline)--non-steroidal anti-inflammatory drug (Vioxx©, Merck Sharp and Dohme, the USA), through an intragastric tube in the dose of 1.25 mg during 8 weeks. In the evaluated material, there was found a greater number of secretory vacuoles and large, containing cholesterol and other lipids as well as generated glucocorticoids, lipid drops in cytoplasm containing prominent endoplasmic reticulum. There were also found cells with cytoplasm of smaller density--especially in apical and basal parts of cells. Mitochondria occasionally demonstrated features of delicate swelling. The observed changes, which occurred on cellular level with application of large doses of the drug, result from mobilization of adaptation mechanisms of the organism.

Medical management update: Peutz Jeghers syndrome

Peutz Jeghers syndrome (PJS) is an autosomal dominant disease characterized by hamartomatous polyposis and distinct mucocutaneous pigmentation. PJS is associated with an increased risk for several cancers and other complications such as small intestine intussusception, short bowel syndrome, and anemia. Medical management mainly consists of treatment of the polyps and surveillance. This medical management update will review clinical concepts, therapeutic advances, and emphasize features of PJS important to the oral health care provider.

NSAIDs downregulate Bcl-X(L) and dissociate BAX and Bcl-X(L) to induce apoptosis in colon cancer cells

Nonsteroidal anti-inflammatory drugs (NSAIDs) are effective in preventing colorectal cancer. Apoptosis induction by NSAIDs plays a critical role in NSAID-mediated chemoprevention. Our previous study demonstrated that NSAIDs require the proapoptotic B-cell non-Hodgkin lymphoma-2 (Bcl-2) family member Bcl-2-associated x protein (BAX) to induce apoptosis and inhibit the expression of antiapoptotic basal cell lymphoma-extra large (Bcl-X(L)) in colon cancer cells. In this study, we further investigated how BAX and Bcl-X(L) mediate NSAID-induced apoptosis. We found that Bcl-X(L) is downregulated by NSAIDs in part through proteasome-mediated protein degradation. NSAIDs promote the dissociation of BAX and Bcl-X(L) and translocation of BAX to the mitochondria. Furthermore, we found that only wild-type BAX, but not a mutant BAX deficient in either protein-protein interaction or mitochondrial localization, was able to restore NSAID-induced apoptosis in the BAX-knockout colon cancer cells. These results suggest that NSAIDs induce apoptosis in colon cancer cells by dissociating BAX and Bcl-X(L), thereby promoting BAX mitochondrial translocation and multimerization.

Aspirin and cancer risk: a summary review to 2007

Aspirin has been associated with a reduced risk of colorectal cancer and--based on limited evidence--to cancers of the oesophagus, stomach, breast, ovary and lung. The role of aspirin on other cancers, such as pancreatic, prostate and bladder cancer and non-Hodgkin's lymphomas and myeloma is less clear, and an increase of risk has been suggested for kidney cancer. For most cancer sites, however, significant heterogeneity between studies, and particularly between study design, was found, with a reduction in risk generally stronger in case-control studies than in cohort ones.

Lipid peroxidation and cyclooxygenase enzyme inhibitory activities of acidic aqueous extracts of some dietary supplements

The botanical supplement market is growing at a fast pace with more and more people resorting to them for maintaining good health. Echinacea, garlic, ginkgo, ginseng, Siberian ginseng, grape seed extract, kava kava, saw palmetto and St John's wort are some of the popular supplements used for a variety of health benefits. These supplements are associated with various product claims, which suggest that they possess cyclooxygenase (COX) enzyme and lipid s inhibitory activities. COX enzymes are found to be at elevated levels in inflamed and cancerous cells. To test some of the product claims, selected supplements were analysed for their ability to inhibit COX-1 and -2 enzymes and lipid peroxidation in vitro. The supplements were extracted with acidified water (pH 2) at 37 degrees C to simulate the gastric environment. The supplements tested demonstrated varying degrees of COX enzyme inhibition (5-85% for COX-1 and 13-28% for COX-2). Interestingly, extracts of garlic (Meijer), ginkgo (Solaray), ginseng (Nature's Way), Siberian ginseng (GNC, Nutrilite, Solaray, Natrol), kava kava (GNC, Sundown, Solaray) and St John's wort (Nutrilite) selectively inhibited COX-2 enzyme. These supplements also inhibited lipid peroxidation in vitro (5-99%). The results indicated that the consumption of these botanical supplements studied possess health benefits.

Celecoxib modulates adhesion of HT29 colon cancer cells to vascular endothelial cells by inhibiting ICAM-1 and VCAM-1 expression

BACKGROUND AND PURPOSE

Cyclooxygenase-2 (COX-2) is highly expressed during inflammation and can promote the progression of colorectal cancer. Interactions between cancer cells and vascular endothelial cells are key events in this process. Recently, the selective COX-2 inhibitor, celecoxib, was shown to inhibit expression of the adhesion molecules, ICAM-1 and VCAM-1, in the human colon cancer cell line HT29 and to inhibit adhesion of HT29 cells to FCS-coated plastic wells. Here, we evaluated the effects of celecoxib on adhesion of HT29 cells to human umbilical vein endothelial cells (HUVEC), mediated by ICAM-1 and VCAM-1, to assess further the potential protective effects of celecoxib on cancer development.

EXPERIMENTAL APPROACH

Celecoxib was incubated for 4 h with HT29 cells and HUVEC and adhesion was quantified by a computerized micro-imaging system. Expression analysis of ICAM-1 and VCAM-1 cell adhesion molecules was performed by western blot.

KEY RESULTS

Celecoxib (1 nM-10 microM) inhibited, with the same potency, adhesion of HT29 cells to resting HUVEC or to HUVEC stimulated by tumour necrosis factor-alpha (TNF-alpha), mimicking inflammatory conditions. Analysis of ICAM-1 and VCAM-1 expression showed that celecoxib inhibited expression of both molecules in TNF-alpha-stimulated HUVEC, but not in resting HUVEC; inhibition was concentration-dependent and maximal (about 50%) at 10 microM celecoxib.

CONCLUSIONS AND IMPLICATIONS

In conclusion, our data show that celecoxib inhibits HT29 cell adhesion to HUVEC and expression of ICAM-1 and VCAM-1, in stimulated endothelial cells. These effects may contribute to the chemopreventive activity of celecoxib in the development of colorectal cancer.

Evaluation of the anti-inflammatory and anti-proliferation tumoral cells activities of Antrodia camphorata, Cordyceps sinensis, and Cinnamomum osmophloeum bark extracts

The extracts of chloroform (1) and methanol (2) from Antrodia camphorata (AC), and chloroform (3) and n-butanol (4) fractions of methanol extract from Cordyceps sinensis (CS), and hexane (5), ethyl acetate (6), and methanol (7) from Cinnamomum osmophloeum bark (CO) were evaluated for their anti-inflammatory as well as tumor-cell growth inhibitory activities in vitro. All the tested extracts dose dependently inhibited the enhanced production of inflammatory mediators such as nitric oxide (NO) through reducing inducible NO synthase expression, and cytokines (tumor necrosis factor (TNF)-alpha and interleukin (IL)-12 in LPS/IFN-gamma activated murine peritoneal macrophages. In addition, extracts 1 from AC, and 5 and 6 from CO significantly arrest the mitogen-stimulated spleen cells in G0/G1 stage. On the other hand, all these extracts were also evaluated for their tumor-cell proliferation activities in different type of cancer cell lines such as Jurkat, HepG2, PC 3, Colon 205, and MCF 7 as well as normal PBMCs. Compared to untreated controls, the extracts 1, 2, and 4-7 were most active and inhibited Jurkat cells with IC50 value of 22, 40, 18, 4, 5, and 45 microg/ml, respectively. In addition, the extracts 5, 6, and 7 from CO showed potent growth inhibition of HepG2 and PC 3 with IC50 values of 35, 80, 55 microg/ml; and 42, 125, and 50 microg/ml, respectively. Similarly, the extracts 1 and 5 inhibited the growth of Colon 205 and MCF 7 cells with IC50 values of 65, 33; and 95 and 30 microg/ml, respectively. Interestingly, none of the tested extract has shown cytotoxicity towards normal PBMCs up to the concentration range studies (0-150 microg/ml). Taken together, these data suggest that the anti-inflammatory and anti-cancer properties of AC, CS, and CO might result from the growth inhibition of NO, TNF-alpha and IL-12, and tumor cells proliferation, respectively.

Effect of aspirin on long-term risk of colorectal cancer: consistent evidence from randomised and observational studies

BACKGROUND

Randomised trials have shown that aspirin reduces the short-term risk of recurrent colorectal adenomas in patients with a history of adenomas or cancer, but large trials have shown no effect in primary prevention of colorectal cancer during 10 years' follow-up. However, the delay from the early development of adenoma to presentation with cancer is at least 10 years. We aimed to assess the longer-term effect of aspirin on the incidence of cancers.

METHODS

We studied the effect of aspirin in two large randomised trials with reliable post-trial follow-up for more than 20 years: the British Doctors Aspirin Trial (N=5139, two-thirds allocated 500 mg aspirin for 5 years, a third to open control) and UK-TIA Aspirin Trial (N=2449, two-thirds allocated 300 mg or 1200 mg aspirin for 1-7 years, a third placebo control). We also did a systematic review of all relevant observational studies to establish whether associations were consistent with the results of the randomised trials and, if so, what could be concluded about the likely effects of dose and regularity of aspirin use, other non-steroidal anti-inflammatory drugs (NSAID), and the effect of patient characteristics.

RESULTS

In the randomised trials, allocation to aspirin reduced the incidence of colorectal cancer (pooled HR 0.74, 95% CI 0.56-0.97, p=0.02 overall; 0.63, 0.47-0.85, p=0.002 if allocated aspirin for 5 years or more). However, this effect was only seen after a latency of 10 years (years 0-9: 0.92, 0.56-1.49, p=0.73; years 10-19: 0.60, 0.42-0.87, p=0.007), was dependent on duration of scheduled trial treatment and compliance, and was greatest 10-14 years after randomisation in patients who had had scheduled trial treatment of 5 years or more (0.37, 0.20-0.70, p=0.002; 0.26, 0.12-0.56, p=0.0002, if compliant). No significant effect on incidence of non-colorectal cancers was recorded (1.01, 0.88-1.16, p=0.87). In 19 case-control studies (20 815 cases) and 11 cohort studies (1 136 110 individuals), regular use of aspirin or NSAID was consistently associated with a reduced risk of colorectal cancer, especially after use for 10 years or more, with no difference between aspirin and other NSAIDs, or in relation to age, sex, race, or family history, site or aggressiveness of cancer, or any reduction in apparent effect with use for 20 years or more. However, a consistent association was only seen with use of 300 mg or more of aspirin a day, with diminished and inconsistent results for lower or less frequent doses.

INTERPRETATION

Use of 300 mg or more of aspirin a day for about 5 years is effective in primary prevention of colorectal cancer in randomised controlled trials, with a latency of about 10 years, which is consistent with findings from observational studies. Long-term follow-up is required from other randomised trials to establish the effects of lower or less frequent doses of aspirin.

NF-kappaB as a potential molecular target for cancer therapy

Nuclear factor kappaB (NF-kappaB), a transcription factor, plays an important role in carcinogenesis as well as in the regulation of immune and inflammatory responses. NF-kappaB induces the expression of diverse target genes that promote cell proliferation, regulate apoptosis, facilitate angiogenesis and stimulate invasion and metastasis. Furthermore, many cancer cells show aberrant or constitutive NF-kappaB activation which mediates resistance to chemo- and radio-therapy. Therefore, the inhibition of NF-kappaB activation and its signaling pathway offers a potential cancer therapy strategy. In addition, recent studies have shown that NF-kappaB can also play a tumor suppressor role in certain settings. In this review, we focus on the role of NF-kappaB in carcinogenesis and the therapeutic potential of targeting NF-kappaB in cancer therapy.

Do older adults using NSAIDs have a reduced risk of colorectal cancer?

BACKGROUND AND OBJECTIVES

Colorectal cancer (CRC) is primarily a disease of older adults. Although NSAIDs are thought to protect from CRC, and long-term use of NSAIDs is common in the elderly, little is known about the impact of NSAID use on CRC risk at advanced age. We specifically reviewed current evidence regarding the effects of NSAIDs on CRC risk in individuals aged > or =65 years, a rapidly growing age group.

STUDY DESIGN

We searched all articles in PubMed published before August 2005. Studies were included if a subgroup analysis of older adults (> or =65 years of age) was performed, or if long-term use of NSAIDs for > or =5 years and CRC risk was investigated. From the selected studies, relevant information, including sample characteristics and association with CRC risk, was extracted and compared.

RESULTS

Altogether 19 studies were identified. Only four studies specifically considered NSAID use in people > or =65 years of age; of these, two showed risk reduction for CRC comparable to that seen in younger age groups or in all age groups. The most informative observational studies found decreasing relative risk of CRC with increasing duration of NSAID use, suggesting substantial risk reduction after 10-20 years of regular use.

CONCLUSIONS

The available data on long-term effects of NSAID use in elderly people are sparse but predominantly indicate risk reduction for CRC comparable to that seen in younger age groups or all ages. Whether and to what degree initiating NSAID use in old age prevents CRC is essentially unknown. In light of the potential adverse effects of NSAIDs, including recent data on adverse cardiovascular outcomes, more information is needed on the minimum effective dose of NSAIDs and the duration of use required in order to evaluate individual risks and benefits in older adults.

Chemoprevention in gastrointestinal cancers: current status

Chemoprevention, pharmacological intervention for disease prevention, aims to intervene in pathways that lead to clinical disease before the disease occurs. Cancer chemoprevention is a relatively new field, but for gastrointestinal cancers, clinical trials have highlighted the chemopreventive potential of several agents. For colorectal neoplasia, trials with aspirin and other non-steroidal anti-inflammatory drugs (NSAIDS) and calcium have demonstrated the most significant reductions of risk. In observational studies, NSAIDs also consistently appear to protect against oesophageal and gastric cancer. Calcium, and perhaps vitamin D, are also promising and have the advantage of being inexpensive, safe interventions. For the prevention of oesophageal cancer, antitumour-B and retinamide have provided hopeful results, although it is not clear that these findings can be extrapolated from the study populations in Asia to western countries. Evidence from China suggests that a combination of beta-carotene, alpha-tocopherol and selenium may protect against oesophageal cancer, but the relative importance of each agent is unclear, and, again, their effects in other populations has not yet been assessed. Mass immunization against hepatitis B seems to be the most effective means of reducing the incidence of hepatocellular cancer worldwide. In addition, treatment with interferon alpha in patients chronically infected with hepatitis C virus shows considerable promise, given the increasing prevalence of hepatitis C virus carriage in recent years. TJ-9, polyprenoic acid and anti-aflatoxin compounds are also possible avenues that deserve future research.

Expression of cyclo-oxygenase-2 in ependymal tumors

Up-regulation of cyclo-oxygenase-2 (COX-2), a cytokine-induced enzyme that metabolizes arachidonic acid into prostaglandins, has been described in some brain tumors, including astrocytomas. Little is known about its expression in ependymal neoplasms. The objective of the present study was to assess COX-2 immunostaining of ependymal tumors. Retrospective COX-2 immunohistochemical analysis was conducted on 117 ependymal tumors. Statistical analysis was performed using Student t-test. The study group (56 men and 44 women, mean age, 30.8 years) was comprised of 48 low-grade ependymomas (WHO grade II), 12 anaplastic ependymomas (WHO grade III), 27 myxopapillary ependymomas (WHO grade I) and 13 subependymomas (WHO grade I). At last known follow-up (range, 12-226 months; mean, 74 months), 52 patients were alive with no evidence of tumor, 16 patients were alive with residual tumor, nine patients died with tumor, one patient died with no tumor and three died with tumor status unknown. Nineteen patients had less than 12 months of follow-up. Thirty-six (36%) patients had tumors, which demonstrated positive COX-2 staining, including 16/27 (59%) myxopapillary ependymomas, 3/13 (23%) subependymomas, 14/48 (29%) ependymomas and 3/12 (25%) anaplastic ependymomas. Statistically significant COX-2 positive immunostaining was observed in myxopapillary ependymomas versus WHO grade II (P = 0.03) and grade III (P = 0.02) tumors. Increased COX-2 expression in myxopapillary ependymoma as compared to the WHO grade II and II ependymoma was observed. The reason for this apparent increased immunoexpression in these low-grade tumors is uncertain. COX-2 inhibitors may play a role in treatment of the subset of ependymal tumors that demonstrate increased expression. COX-2 staining did not reliably predict tumor behavior.

Aspirin and cancer risk: an updated quantitative review to 2005

Aspirin has been associated to a reduced risk of colorectal, and possibly of a few other common cancers. Epidemiological studies on aspirin and cancer risk published up to December 2005 have been reviewed, and pooled relative risks (RR) for several cancers have been provided. Besides a reduction in the risk of cancer of the colorectum (RR = 0.71, 95% confidence interval, CI: 0.67-0.75), there is evidence-although more limited, and mainly from case-control studies-that aspirin has a favourable effect on cancers of the esophagus (RR = 0.72, 95% CI: 0.62-0.84), stomach (RR = 0.84, 95% CI: 0.76-0.93), breast (RR = 0.91, 95% CI: 0.88-0.95), ovary (RR = 0.89, 95% CI: 0.78-1.02) and lung (RR = 0.94, 95% CI: 0.89-1.00). The role of aspirin on other cancers, such as pancreatic, prostate, bladder cancer, and non-Hodgkins' lymphomas is less clear, and an increase of risk has been suggested for kidney cancer. For most cancer sites, however, significant heterogeneity between studies, and particularly across study design, was found, with a reduction in risk generally stronger in case-control than in cohort studies. Further, notwithstanding the large amount of epidemiological evidence, substantial uncertainties remain about the proper aspirin dose and duration of treatment.

Non-steroidal anti-inflammatory drugs for cancer prevention: promise, perils and pharmacogenetics

Aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) show indisputable promise as chemopreventive agents. Possible targets include cancers of the colon, stomach, breast and lung. However, recent studies raise concern about potential cardiovascular toxicity associated with the use of NSAIDs that specifically target the enzyme cyclooxygenase 2. These findings, and others that show that inherited genetic characteristics might determine preventive success, argue for new strategies that are tailored to individual medical history and genetic make-up.

Mast cell tryptase stimulates DLD-1 carcinoma through prostaglandin- and MAP kinase-dependent manners

We found that striptease-positive mast cells were abundant in the invasive front of human colon adenocarcinoma by examining 30 cases. Because tryptase has been suggested to be the agonist proteinase for protease-activated receptor-2 (PAR-2), we investigated the effects of stimulation of PAR-2 by tryptase on the cell signaling and proliferation of DLD-1, a human colon carcinoma cell line. PAR-2 stimulation by tryptase induced the increase in [Ca(2+)](i), which was desensitized by the prior application of PAR-2 activating peptide (AP). The proliferative responses of DLD-1 to tryptase and PAR-2 AP were associated with the phosphorylation of MEK and MAP kinase. Inhibition of MEK by PD98059 completely inhibited the proliferation-enhancing effects of tryptase and PAR-2 AP as well as phosphorylation of MAP kinase. Moreover, tryptase and PAR-2 AP stimulated the production of prostaglandin E2 and the inhibition of prostaglandin synthesis by indomethacin or NS398 resulted in the complete inhibition of the proliferative responses to tryptase and PAR-2 AP. Furthermore, the tryptase-stimulated proliferation of DLD-1 was concentration-dependently inhibited by nafamostat mesilate, a specific inhibitor of tryptase. These results as a whole indicated that tryptase has proliferative effects on DLD-1 through cyclooxygenase- and MAP kinase-dependent manners acting on PAR-2 by its proteolytic activity.

Developmental Phases of Inflammation-Induced Massive Lymphoid Hyperplasia and Extensive Changes in Epithelium in an Experimental Model of Allergy

Direct evidence that inflammation is linked to carcinogenesis has yet to be established. Very few data are available on the developmental phases of inflammation-induced immune dysfunction that may lead to tumorigenesis. In a series of studies conducted in the 1980s and 1990s, an experimental model of acute and chronic inflammation was established in guinea pig conjunctiva by topical application of fluoresceinyl ovalbumin (FLOA) for up to 30 months. In this updated report, some of the findings are reanalyzed and expanded to identify that at lease 3 developmental phases were involved during the entire course of inflammatory responses including (1) an acute response (phase A) involving IgE-mast cell sensitization and degranulation; (2) an intermediate phase (phase B), a desensitization phenomenon and loss of mast cell function and neovascularization; (3) a chronic response (phase C) and induction of massive lymphoid hyperplasia, follicular formation with germinal centers, increased swollen goblet cells, extensive epithelial thickening and thinning, and angiogenesis. The results suggest evidence of a direct association between inflammation and the development of tumor-like lesions in lymphoid tissues and extensive changes in adjacent epithelia. Confirmation that inflammation induces irreversible changes in lymphoid and epithelial tissues leading to lymphoid tumorigenesis and/or carcinogenesis requires further studies. Understanding the developmental phases of immune dysfunction may provide unique opportunities for diagnosis and treatment of inflammatory diseases, autoimmune disorders, and cancers including lymphomas associated with Sjogren syndrome, squamous cell carcinoma of the conjunctiva, and other lymphomas or epithelial cancers. It is suggested that inflammatory mediators are ideal targets (biomarkers) for diagnosis, chemoprevention, and therapy for several cancers.

Antiviral therapy with non-selective β-blockers: preliminary experimental and clinical corroboration

Treatment with non-selective beta-blockers has been proposed to have an indirect antiviral activity acting via an enhanced performance of the immune system, and the mechanism of this activity has been laid out earlier. Experimental and clinical findings are presented that corroborate the hypothesis that inhibiting the immunosuppressive and stress-related cAMP-PKA pathway will enhance the immune system's ability to recognize foreign antigen and to access its vast repertory in an improved way, resulting in an indirect antiviral activity. Other drugs having an inhibitory effect on the cAMP-PKA pathway in cells of the immune system and therefore expected to have a comparable activity spectrum with different specific side-effects are presented, for example aspirin. Additionally the so far unexplained anticancer activity of aspirin is related to the same mechanism of an enhanced performance of the immune system.

Tumor cell proliferation and cyclooxygenase enzyme inhibitory compounds in Amaranthus tricolor

Amaranthus tricolor is consumed as a vegetable in Asia. Bioassay-directed isolation of leaves and stems of A. tricolor yielded three galactosyl diacylglycerols (1-3) with potent cyclooxygenase and human tumor cell growth inhibitory activities. The purified compounds were characterized by spectroscopic methods. In addition, the fatty acid moieties in diacyl galactosyl glyerols were characterized by GC-MS analyses. The galactosyl diacylglycerols 1-3 inhibited the cyclooxygenase-1 (COX-1) enzyme by 78, 63, and 93% and the cyclooxygenase-2 (COX-2) enzyme by 87, 74, and 95%, respectively. These compounds were tested for antiproliferative activity using human AGS (gastric), CNS (central nervous system; SF-268), HCT-116 (colon), NCI-H460 (lung), and MCF-7 (breast) cancer cell lines. Compound 1 inhibited the growth of AGS, SF-268, HCT-116, NCI-H460, and MCF-7 tumor cell lines with IC50 values of 49.1, 71.8, 42.8, 62.5, and 39.2 mug/mL, respectively. For AGS, HCT-116, and MCF-7 tumor cell lines, the IC50 values of compounds 2 and 3 were 74.3, 71.3, and 58.7 microg/mL and 83.4, 73.1, and 85.4, respectively. This is the first report of the COX enzyme inhibitory activity for galactosyl glycerols and antiproliferative activities against human colon, breast, lung, stomach, and CNS tumor cell lines.

The cost-effectiveness of aspirin versus cyclooxygenase-2-selective inhibitors for colorectal carcinoma chemoprevention in healthy individuals

BACKGROUND

Aspirin therapy is accepted widely for secondary prevention in patients with documented cardiovascular disease, but there is a growing trend among healthy individuals to use aspirin as primary chemoprevention for both cardiovascular and oncologic diseases. Accruing evidence suggests that cyclooxygenase-2-selective inhibitors (coxibs) may be effective for colorectal carcinoma (CRC) chemoprevention but would not provide the primary cardiac benefit of aspirin.

METHODS

A computer-based Markov model simulated hypothetical cohorts of healthy men age 50 years who took either 325 mg of enteric-coated aspirin daily or celecoxib at a dose of 400 mg twice a day. Patients in both cohorts could develop drug-related complications that would lead to its discontinuation. The aspirin group also was modeled to have a decreased rate of coronary ischemic events; however, decreased CRC mortality was not modeled in either group based on the assumption that the two treatments were effective equally in this regard. Data sources included published literature and the Centers for Medicare and Medicaid Services. Endpoints used to compare the two strategies included quality-adjusted life years (QALYs), mortality and complication rates, and cost. The analysis was from a societal perspective with a time horizon of 10 years from age 50 years. Extensive sensitivity analyses were performed.

RESULTS

Aspirin therapy resulted in 0.03 more QALYs and cost $23,000 less than coxib therapy over a 10-year period. Compared with the aspirin group, the coxib group had 3.877% more complications and 0.17% more deaths. Alternatively stated, coxib therapy resulted in 1 patient complication or death for every 26 or 588 patients treated with coxibs, respectively.

CONCLUSIONS

Assuming equal efficacy in CRC prevention over a 10-year period, aspirin was both more effective and less costly than coxib therapy when used for primary chemoprevention of CRC.

Celecoxib derivatives induce apoptosisvia the disruption of mitochondrial membrane potential and activation of caspase 9

Celecoxib is a potent nonsteroid antiinflammatory drug (NSAID) that has shown great promise in cancer chemoprevention and treatment. The tumor suppression activity of celecoxib and other NSAIDs have been related to the induction of apoptosis in many cancer cell lines and animal models. While celecoxib is a specific inhibitor of cyclooxygenase (COX)-2, recent data indicate that its apoptotic properties may also be mediated through COX-independent pathways. In our study, we evaluated second generation celecoxib derivatives, lacking COX-2 inhibitory activity, in a premalignant and malignant human oral cell culture model to determine their potential anticancer effect and mechanisms responsible for the COX-independent apoptotic activity. Celecoxib and its derivatives delayed the progression of cells through the G(2)/M phase and induced apoptosis. The derivatives with apolar substituents at the terminal phenyl moiety of celecoxib greatly enhanced apoptosis and cell cycle delay. Apoptosis and cell cycle arrest appeared to be independent of derivative induced inhibition of PDK1 and phosphorylation of Akt and Erk1/2. Derivatives induced apoptosis was mediated by the cleavage and activation of caspase-9 and caspase-3, but not caspase 8, implicating the mitochondrial pathway for apoptosis induction. Inhibitors of caspase-3 and caspase-9 and cyclosporin A, a mitochondrial membrane potential stabilizer, attenuated derivative induced apoptosis. Inhibition of caspase-3 prevented the activation of caspase 8, while the inhibition of caspase-9 inhibitor blocked activation of both caspase 3 and 8 by the derivatives. Apoptosis was independent of Bcl-2. These results indicate that the second generation celecoxib derivatives induce apoptosis in human oral cancer lines by the disruption of mitochondrial membrane potential activating caspase 9 and downstream caspase 3 and 8. This suggests that the modification of the celecoxib structure can lead to highly effective COX-independent growth inhibitory and apoptotic agents in chemoprevention and therapy.