celecoxib, Celebrex
Targeting cyclooxygenase-2 reduces overt toxicity toward low-dose vinblastine and extends survival of juvenile mice with Friend disease.

Cervi D, Klement G, Stempak D, Baruchel S, Koki A, Ben-David Y.

Department of Medical Biophysics, Sunnybrook and Women's College Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada M4N 3M5.

PURPOSE: To test the efficacy of selective therapy against cyclooxygenase-2 in combination with a low-dose regimen of a cytotoxic agent in the treatment of juvenile hematopoietic malignancies in the experimental model, Friend disease. EXPERIMENTAL DESIGN: Juvenile erythroleukemic mice (n = 8) received no treatment, celecoxib (1600 mg/kg/d), vinblastine (0.5 microg/g twice weekly), vehicle controls, or celecoxib + vinblastine combination (n = 9) over a 6-month period from time of tumor induction. Overt toxicity was assessed daily and recorded weekly. RESULTS: Among randomly selected mice from celecoxib treatment groups, plasma concentrations ranged from 2 to 6 micromol/L. As a single agent, celecoxib was not associated with any apparent toxicity. Monotherapy with vinblastine, however, caused early mortality marked by severe diarrhea, lethargy, and weight loss. At the tested doses, neither vinblastine nor celecoxib enhanced survival as monotherapies. Coadministration of these two drugs alleviated the overt toxicity associated with vinblastine and resulted in a significant increase in survival (P < 0.05). Survivors sampled throughout the study showed a trend to decreased weight loss and hematocrit levels among all groups, but significance was evidenced earlier in the vinblastine monotherapy group overall (P < 0.05). Despite similar degree of splenomegaly, histologic analysis revealed preserved splenic mantle architecture from mice given combination therapy compared with those sampled from mice on all other monotherapies, exhibiting a more diffuse burden of blasts and destruction of germinal centers. CONCLUSION: We propose that addition of a selective cyclooxygenase-2 inhibitor to a modified low-dose conventional chemotherapeutic regimen protects juvenile mice with Friend disease from succumbing to low-dose cytotoxicity, in part, by neutralizing acute inflammatory responses.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15701860&dopt=Abstract celecoxib, Celebrex



celecoxib, Celebrex
A combination of docosahexaenoic acid and celecoxib prevents prostate cancer cell growth in vitro and is associated with modulation of nuclear factor-kappaB, and steroid hormone receptors.

Narayanan NK, Narayanan BA, Reddy BS.

Department of Environmental Medicine, New York University School of Medicine, Tuxedo, NY 10987, USA. nnarayan env.med.nyu.edu

Epidemiological studies have provided evidence that high intake of saturated fat and/or animal fat increases the risk of prostate cancer, but on the other hand, diets rich in omega-3 polyunsaturated fatty acids (n-3 PUFAs), present in fish oils were found to reduce the risk. There are indications of an increased expression of immunoreactive PPARgamma in prostatic intraepithelial neoplasia (PIN) and prostate cancer, suggesting that PPARgamma ligands may exert their own potent anti-proliferative effect against prostate cancer. The experimental evidence for the role of cyclooxygenase-2 (COX-2) in prostate carcinogenesis is well established through several investigations. It clearly suggests the need for development of strategies to inhibit COX-2 mediated prostate carcinogenesis. However, administration of high doses of COX-2 inhibitors, such as celecoxib, over longer periods may not be devoid of side effects. We assessed the efficacy of DHA and celecoxib individually and in combination at low doses in three prostate cancer cell lines (LNCaP, DU145 and PC-3) measuring cell growth inhibition and apoptosis, and on the levels of expression of COX-2, nuclear factor-kappaB (NF-kappaBp65), and nuclear receptors, such as PPARgamma and retinoid X receptors (RXR), all of which presumably participate in prostate carcinogenesis. A 48-h incubation of prostate cancer cells with 5 microM each of DHA or celecoxib induced cell growth inhibition and apoptosis, and altered the expression of the above molecular parameters. Interestingly, the modulation of these cellular and molecular parameters was more pronounced in cells treated with low doses of DHA and celecoxib (2.5 microM each) in combination than in cells treated with the higher doses of individual agents. In conclusion, the present study demonstrates for the first time that a combination of lower doses of the n-3 PUFA, and DHA with the selective COX-2 inhibitor celecoxib effectively modulates the above cellular and molecular parameters that are relevant to prostate cancer. This raises the intriguing prospect that the use of low doses of a COX-2 inhibitor in combination with an n-3 PUFA could be a highly promising strategy for prostate cancer chemoprevention while minimizing undesired side effects.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15703837&dopt=Abstract celecoxib, Celebrex



celecoxib, Celebrex
Video capsule endoscopy to prospectively assess small bowel injury with celecoxib, naproxen plus omeprazole, and placebo.

Goldstein JL, Eisen GM, Lewis B, Gralnek IM, Zlotnick S, Fort JG.

Background & Aims: Data indicate that cyclooxygenase-2-specific inhibitors cause less gastroduodenal mucosal damage than nonspecific NSAIDS, but their effects on the small bowel mucosa are less well recognized. In a multicenter, double-blind, placebo-controlled trial with video capsule endoscopy (VCE) we prospectively evaluated the incidence of small bowel injury in healthy subjects treated with celecoxib compared to naproxen plus omeprazole. Methods: We randomly assigned subjects with normal baseline VCEs to celecoxib 200 mg twice daily (n = 120), naproxen 500 mg twice daily plus omeprazole 20 mg once daily (n = 118), or placebo (n = 118) for 2 weeks. The primary end point was the mean number of small bowel mucosal breaks per subject. Results: Baseline VCE found small bowel lesions in 13.8% (57/413) of screened subjects, who became ineligible for randomization. The mean number of small bowel mucosal breaks per subject and the percentage of subjects with these mucosal breaks were 2.99 +/- 0.51, 55% for naproxen/omeprazole compared to 0.32 +/- 0.10, 16% for celecoxib and 0.11 +/- 0.04, 7% for placebo ( P < .001, both comparisons). The magnitude of the difference between celecoxib and placebo was small but statistically significant ( P = .04). Conclusions: Among healthy subjects with lesion-free baseline VCEs, celecoxib was associated with significantly fewer small bowel mucosal breaks than naproxen plus omeprazole. This study also showed that the background incidence of small bowel lesions in healthy adults is not insignificant and should be considered in future trials with VCE.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15704047&dopt=Abstract celecoxib, Celebrex



celecoxib, Celebrex
The restorative effect of a selective cyclooxygenase-2 inhibitor on urothelial cell-cell interactions after partial bladder outlet obstruction in rats.

Erdogru T, Celik-Ozenci C, Seval Y, Emreoglu I, Ustunel I, Korgun E, Koksal TI, Baykara M, Demir R.

Department of Urology, Akdeniz University Faculty of Medicine, Antalya, Turkey.

OBJECTIVE To determine the changes in cyclooxygenase-2 (COX-2), E-cadherin and alpha-catenin expression after partial bladder outlet obstruction (PBOO), and whether a selective COX-2 inhibitor (celecoxib) might inhibit COX-2 expression and have beneficial effects on urothelial cell-to-cell interactions in rats subjected to PBOO. MATERIALS AND METHODS Thirty-six male rats were divided into six equal groups; celecoxib was administered after creating PBOO for 1 and 4 weeks in groups 1 and 2, respectively. Two further obstructed groups (3 and 4, PBOO for 1 and 4 weeks, respectively) received no treatment. Sham-operated animals served as controls (group 5 and 6, assessed at 1 and 4 weeks, respectively). After 1 and 4 weeks of PBOO or a sham procedure the bladder weight was recorded before sampling the bladder for Western blotting and immunohistological analysis, to assess the expressions of COX-2 and adherens proteins, E-cadherin and alpha-catenin. Urothelial cell-to-cell interactions were evaluated using electron microscopy. RESULTS The bladder mass increased rapidly during the first 7 days after PBOO in groups 1-4 compared with 5 and 6 (P < 0.05). While the bladder mass then continued to increase for the next 21 days in group 4, it was constant in group 2 (P < 0.001). Immunohistochemical staining and Western blotting analyses showed that E-cadherin and alpha-catenin expression were reversibly decreased in rats with PBOO, while COX-2 protein expression was up-regulated. After giving celecoxib there was a significant decrease in COX-2 expression and a restoration of intercellular adherens junctions and desmosomes, as assessed on electron microscopy and expression of adherens proteins combined. CONCLUSION The increase in COX-2 expression attributable to hypoxia and the tensile strength of bladder wall was attenuated by celecoxib. Selective COX-2 inhibitors have important restorative effects on intercellular adherens junctions and desmosomes in PBOO.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15705100&dopt=Abstract celecoxib, Celebrex



celecoxib, Celebrex
Risk of acute myocardial infarction and sudden cardiac death in patients treated with cyclo-oxygenase 2 selective and non-selective non-steroidal anti-inflammatory drugs: nested case-control study.

Graham DJ, Campen D, Hui R, Spence M, Cheetham C, Levy G, Shoor S, Ray WA.

Office of Drug Safety, Center for Drug Evaluation and Research, Food and Drug Administration, Rockville, MD, USA. GRAHAMD cder.fda.gov

BACKGROUND: Controversy has surrounded the question about whether high-dose rofecoxib increases or naproxen decreases the risk of serious coronary heart disease. We sought to establish if risk was enhanced with rofecoxib at either high or standard doses compared with remote non-steroidal anti-inflammatory drug (NSAID) use or celecoxib use, because celecoxib was the most common alternative to rofecoxib. METHODS: We used data from Kaiser Permanente in California to assemble a cohort of all patients age 18-84 years treated with a NSAID between Jan 1, 1999, and Dec 31, 2001, within which we did a nested case-control study. Cases of serious coronary heart disease (acute myocardial infarction and sudden cardiac death) were risk-set matched with four controls for age, sex, and health plan region. Current exposure to cyclo-oxygenase 2 selective and non-selective NSAIDs was compared with remote exposure to any NSAID, and rofecoxib was compared with celecoxib. FINDINGS: During 2302029 person-years of follow-up, 8143 cases of serious coronary heart disease occurred, of which 2210 (27.1%) were fatal. Multivariate adjusted odds ratios versus celecoxib were: for rofecoxib (all doses), 1.59 (95% CI 1.10-2.32, p=0.015); for rofecoxib 25 mg/day or less, 1.47 (0.99-2.17, p=0.054); and for rofecoxib greater than 25 mg/day, 3.58 (1.27-10.11, p=0.016). For naproxen versus remote NSAID use the adjusted odds ratio was 1.14 (1.00-1.30, p=0.05). INTERPRETATION: Rofecoxib use increases the risk of serious coronary heart disease compared with celecoxib use. Naproxen use does not protect against serious coronary heart disease.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15705456&dopt=Abstract celecoxib, Celebrex



celecoxib, Celebrex
Cardiovascular Risk Associated with Celecoxib in a Clinical Trial for Colorectal Adenoma Prevention.

Solomon SD, McMurray JJ, Pfeffer MA, Wittes J, Fowler R, Finn P, Anderson WF, Zauber A, Hawk E, Bertagnolli M.

Background Selective cyclooxygenase-2 (COX-2) inhibitors have come under scrutiny because of reports suggesting an increased cardiovascular risk associated with their use. Experimental research suggesting that these drugs may contribute to a prothrombotic state provides support for this concern. Methods We reviewed all potentially serious cardiovascular events among 2035 patients with a history of colorectal neoplasia who were enrolled in a trial comparing two doses of celecoxib (200 mg or 400 mg twice daily) with placebo for the prevention of colorectal adenomas. All deaths were categorized as cardiovascular or noncardiovascular, and nonfatal cardiovascular events were categorized in a blinded fashion according to a prespecified scheme. Results For all patients except those who died, 2.8 to 3.1 years of follow-up data were available. A composite cardiovascular end point of death from cardiovascular causes, myocardial infarction, stroke, or heart failure was reached in 7 of 679 patients in the placebo group (1.0 percent), as compared with 16 of 685 patients receiving 200 mg of celecoxib twice daily (2.3 percent; hazard ratio, 2.3; 95 percent confidence interval, 0.9 to 5.5) and with 23 of 671 patients receiving 400 mg of celecoxib twice daily (3.4 percent; hazard ratio, 3.4; 95 percent confidence interval, 1.4 to 7.8). Similar trends were observed for other composite end points. On the basis of these observations, the data and safety monitoring board recommended early discontinuation of the study drug. Conclusions Celecoxib use was associated with a dose-related increase in the composite end point of death from cardiovascular causes, myocardial infarction, stroke, or heart failure. In light of recent reports of cardiovascular harm associated with treatment with other agents in this class, these data provide further evidence that the use of COX-2 inhibitors may increase the risk of serious cardiovascular events. Notice: Because of its potential public health implications, this article was published at www.nejm.org on February 15, 2005. It will appear in the March 17 issue of the Journal. Click on "PDF" for the full text. Copyright 2005 Massachusetts Medical Society.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15713944&dopt=Abstract celecoxib, Celebrex



celecoxib, Celebrex
Phase I/II study of selective cyclooxygenase-2 inhibitor celecoxib as a radiation sensitizer in patients with unresectable brain metastases.

Cerchietti LC, Bonomi MR, Navigante AH, Castro MA, Cabalar ME, Roth BM.

Translational Research Unit, Universidad de Buenos Aires, Argentina. lcerchie aecom.yu.edu

PURPOSE: The primary goal of this phase I/II study was to evaluate the feasibility, safety and efficacy of celecoxib administered concomitant to radiotherapy to treat unresectable BM. PATIENTS AND METHODS: Patients with measurable BM by CT or MRI, unresectability criteria by a neurosurgeon and RPA-RTOG class II were eligible. Celecoxib was administered at 400 mg/day during the entire course of radiotherapy. All patients were irradiated with 60Co beams to whole-brain dose of 32 Gy (20 fractions of 1.6 Gy each two times a day with a 6 h interval between treatments) followed by a 22.4 Gy boost (same fractionation schedule) over evident lesions. RESULTS: Twenty-seven patients were treated. The concurrent regimen was well tolerated with 15 cases of mild dyspepsia. Alopecia (NCI grades 1-2) was the most important side effect. Three patients presented rash/desquamation of moderate intensity. Radiological responses occurred in 18 of 25 valuable patients (72), with five complete responses (CR). Symptomatic responses were reported in 25 of 27 patients (92.6), with 20 CR. The overall response rate (considering complete plus partial responses) was 66.7. Percentile 50 for time-to-progression, time-to-neurological-progression and functional-independence-time were 3, 6.25 and 6.7 months, respectively. Median survival time was 8.7 months. CONCLUSION: Our initial results suggest that radiotherapy plus celecoxib is safe and a possible active treatment for patients with BM. Further investigation in a randomized trial is warranted to validate its clinical utility.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15719279&dopt=Abstract celecoxib, Celebrex