Clinical pharmacology of celecoxib, a COX-2 selective inhibitor

The pharmacology of antiplatelet agents for primary, secondary, and tertiary prevention of ischemic stroke

INTRODUCTION

Ischemic etiology accounts for two thirds of all strokes in which platelet activation and aggregation play a major role. A variety of antiplatelet therapies have been tested for primary, secondary, and tertiary prevention, with certain patient subtypes benefiting more than others from a specific regimen.

AREAS COVERED

This review aims at synthetizing current evidence on pharmacology of antiplatelet agents approved for primary, secondary, and tertiary stroke prevention and their application among possible patient subtypes that may benefit more from their administration.

EXPERT OPINION

Management of ischemic stroke has largely evolved over the past decades. A better understanding of stroke pathophysiology has allowed to identify patients who can benefit most from antiplatelet therapies, with varying degrees of benefit depending on whether these agents are being used for primary, secondary, or tertiary prevention. Importantly, the antiplatelet treatment regimens currently available have expanded and no longer limited to aspirin but include other drugs such as P2Y12 and phosphodiesterase inhibitors, also used in combination, as well as precision medicine approaches using genetic testing aiming at optimizing the safety and efficacy in this population.

YidC as a potential antibiotic target

The membrane insertase YidC, is an essential bacterial component and functions in the folding and insertion of many membrane proteins during their biogenesis. It is a multispanning protein in the inner (cytoplasmic) membrane of Escherichia coli that binds its substrates in the "greasy slide" through hydrophobic interaction. The hydrophilic part of the substrate transiently localizes in the groove of YidC before it is translocated into the periplasm. The groove, which is flanked by the greasy slide, is within the center of the membrane, and provides a promising target for inhibitors that would block the insertase function of YidC. In addition, since the greasy slide is available for the binding of various substrates, it could also provide a binding site for inhibitory molecules. In this review we discuss in detail the structure and the mechanism of how YidC interacts not only with its substrates, but also with its partner proteins, the SecYEG translocase and the SRP signal recognition particle. Insight into the substrate binding to the YidC catalytic groove is presented. We wind up the review with the idea that the hydrophilic groove would be a potential site for drug binding and the feasibility of YidC-targeted drug development.

An enhanced first derivative synchronous spectrofluorimetric method for determination of the newly co-formulated drugs, amlodipine and celecoxib in pharmaceutical preparation and human plasma

BACKGROUND

A new combination of amlodipine and celecoxib has been recently introduced in order to relieve the symptoms of osteoarthritis and help treat hypertension that commonly associated with osteoarthritis.

OBJECTIVE

The current study is the first to develop and optimize a sensitive, simple and accurate first derivative synchronous spectrofluorimetric method for the simultaneous determination of amlodipine and celecoxib in bulk powder, pharmaceutical preparation and spiked human plasma.

METHOD

The method implies the use of synchronous methodology using Δλ = 100 nm and measuring the fluorescence amplitudes of the first derivative each at the zero-crossing point of the other. For amlodipine and celecoxib, the emission wavelengths were at 455 nm and 368 nm, after excitation at 367 nm and 264 nm, respectively.

RESULTS

The method was found to be linear over a wide concentration ranges of (5-600 ng/ml), (100-2000 ng/ml) with lower limits of detection of (1.16 ng/ml) and (17.16 ng/ml) for amlodipine and celecoxib, respectively. Enhancement of the fluorescence intensity was achieved by complex formation between the studied drugs and the surfactant sodium dodecyl sulfate and optimizing other experimental conditions. The method was further extended for application for determination of the studied drugs in spiked human plasma with excellent % recoveries of (95.20 ± 6.095) and (98.67 ± 6.394) for amlodipine and celecoxib, respectively. Validation of the method was successfully implemented according to recommendations delivered by guidelines of the International Conference on Harmonization.

Efficacy of Ciprofloxacin/Celecoxib combination in zebrafish models of amyotrophic lateral sclerosis

OBJECTIVE

To evaluate the efficacy of a fixed-dose combination of two approved drugs, Ciprofloxacin and Celecoxib, as a potential therapeutic treatment for amyotrophic lateral sclerosis (ALS).

METHODS

Toxicity and efficacy of Ciprofloxacin and Celecoxib were tested, each alone and in distinct ratio combinations in SOD1 G93R transgenic zebrafish model for ALS. Quantification of swimming measures following stimuli, measurements of axonal projections from the spinal cord, neuromuscular junction structure and morphometric analysis of microglia cells were performed in the combination- treated vs nontreated mutant larvae. Additionally, quantifications of touch-evoked locomotor escape response were conducted in treated vs nontreated zebrafish expressing the TARDBP G348C ALS variant.

RESULTS

When administered individually, Ciprofloxacin had a mild effect and Celecoxib had no therapeutic effect. However, combined Ciprofloxacin and Celecoxib (Cipro/Celecox) treatment caused a significant increase of ~ 84% in the distance the SOD1 G93R transgenic larvae swam. Additionally, Cipro/Celecox elicited recovery of impaired motor neurons morphology and abnormal neuromuscular junction structure and preserved the ramified morphology of microglia cells in the SOD1 mutants. Furthermore, larvae expressing the TDP-43 mutation displayed evoked touch responses that were significantly longer in swim distance (110% increase) and significantly higher in maximal swim velocity (~44% increase) when treated with Cipro/Celecox combination.

INTERPRETATION

Cipro/Celecox combination improved locomotor and cellular deficits of ALS zebrafish models. These results identify this novel combination as effective, and may prove promising for the treatment of ALS.

Development of a Unified Reversed-Phase HPLC Method for Efficient Determination of EP and USP Process-Related Impurities in Celecoxib Using Analytical Quality by Design Principles

This article presents the development of a reversed-phase (RP) high-performance liquid chromatographic (HPLC) method for determination of process-related impurities in a celecoxib drug substance following Analytical Quality by Design (AQbD) principles. The method from European Pharmacopeia (EP) for celecoxib drug substance does not sufficiently separate celecoxib from its EP impurity B because the system suitability criterion is not achieved (resolution NLT 1.8). The same issue was observed with the proposed method from United States Pharmacopeia (USP) for celecoxib capsules, where EP impurity A elutes under the main peak. A new HPLC method was developed that eliminates the disadvantages of the two pharmacopeial methods and is capable of efficiently separating and determining all seven impurities listed in EP and the proposed USP monographs. The development of a new HPLC method started with method scouting, in which various C18 and phenyl stationary phases were tested. Improved selectivity was obtained only with a chiral stationary phase. An immobilized Chiralpak IA-3 column used in RP mode turned out to be the most appropriate for method optimization. The ratio of acetonitrile in the mobile phase, flow rate, and column temperature were recognized as critical method parameters (CMPs) and were further investigated using a central composite face response-surface design. A multiple linear regression (MLR) method was applied to fit the mathematical models on the experimental data to determine factor-response relationships. The models created show adequate fit and good prediction abilities. The Monte Carlo simulation method was used to establish the design space. The method developed was verified in terms of precision, sensitivity, accuracy, and linearity, and the results showed that the new method is suitable for determination of seven process-related impurities of celecoxib.

A journey of celecoxib from pain to cancer

The most enthralling and versatile class of drugs called the Non-steroidal anti-inflammatory (NSAIDs) showed its therapeutic utility in inflammation, beginning from the era of classic drug 'Aspirin'. NSAIDs and their well-established action based on inhibiting the COX-1 and COX-2 enzyme leads to blockage of prostaglandin pathway. They further categorized into first generation (non-selective inhibitor) and second generation (selective COX-2 inhibitors). Selective COX-2 inhibitors has advantage over non-selective in terms of their improved safety profile of gastro-intestinal tract. Rejuvenating and recent avenues for COXIBS (selective COX-2 inhibitors) explains its integrated role in identification of biochemical pain signaling as well as its pivotal key role in cancer chemotherapy. A key role player in this class is the Celecoxib (only FDA approved COXIB) a member of Biopharmaceutical classification system (BCS) II. Low solubility and bioavailability issues related with celecoxib lead to the development and advancement in the discovery and research of some possible formulation administered either orally, topically or via transdermal route. This review article intent to draw the bead on Celecoxib and it clearly explain extensive knowledge of its disposition profile, its dynamic role in cancer at cellular level and cardiovascular risk assessment. Some of the possible formulations approaches with celecoxib and its improvement aspects are also briefly discussed.

Celecoxib for the treatment of musculoskeletal arthritis

Introduction: The cyclooxygenase (COX)-2 inhibitor celecoxib is an approved compound for rheumatoid (RA) and osteoarthritis (OA), combining both anti-inflammatory and analgesic properties with a good gastrointestinal tolerability. Areas covered: This article covers the pharmacological properties and clinical efficacy as well as the latest safety data available for celecoxib with emphasis on the treatment of RA and OA. It is based primarily on a current literature search on PubMed and Web of Science, but also on the professional rheumatological expertise of the authors. Expert opinion: Celecoxib has been shown to be superior to placebo and equivalent to traditional non-steroidal anti-inflammatory drugs (tNSAIDs). Many studies have been published making celecoxib a good and safe treatment option in particular in moderate arthritis and patients without established cardiovascular (CV) disease. Moreover, older patients might gain significant benefits compared to tNSAIDs due to reduced gastrointestinal events even when having a history of ulcer bleedings. Nonetheless, there is still much to learn, especially regarding the prescription of celecoxib in patients with cardiovascular co-morbidities. While low doses seem to be safe according to present data, the knowledge on the more effective, higher doses >400 mg/day is still limited.

Amlodipine and celecoxib for treatment of hypertension and osteoarthritis pain

INTRODUCTION

Osteoarthritis constitutes one of the leading causes of pain and disability worldwide with a significant impact on health-care costs. Patients with osteoarthritis are often affected by a number of cardiovascular comorbidities, including hypertension, which is present in about 40% of cases. Just recently, a single tablet combination of amlodipine besylate, a calcium channel blocker, and celecoxib, a nonsteroidal anti-inflammatory drug, indicated for patients for whom treatment with amlodipine for hypertension and celecoxib for osteoarthritis are appropriate, has been recently approved. Areas covered: We reviewed data from clinical studies that investigated safety and efficacy of the combination of amlodipine and celecoxib in hypertensive patients with osteoarthritis published before 31 August 2018. The literature search was conducted using research Methodology Filters. Expert commentary: The advantages of this single formulation over sequential administration include increased compliance, possibly reduced cost, and less likelihood of dosage-related issues. Moreover, this single tablet formulation combines the anti-inflammatory activity of the celecoxib with the systemic vasodilatation induced by the amlodipine. It is a promising treatment for patients with osteoarthritis and hypertension. Nevertheless, celecoxib may cause a variable degree of blood pressure increase and only a small clinical trial has been conducted before approval to assess interactions related to blood pressure effect between these two molecules.

Recent advances in improving oral drug bioavailability by cocrystals

Introduction: Oral drug delivery is the most favored route of drug administration. However, poor oral bioavailability is one of the leading reasons for insufficient clinical efficacy. Improving oral absorption of drugs with low water solubility and/or low intestinal membrane permeability is an active field of research. Cocrystallization of drugs with appropriate coformers is a promising approach for enhancing oral bioavailability.

Methods: In the present review, we have focused on recent advances that have been made in improving oral absorption through cocrystallization. The covered areas include supersaturation and its importance on oral absorption of cocrystals, permeability of cocrystals through membranes, drug-coformer pharmacokinetic (PK) interactions, conducting in vivo-in vitro correlations for cocrystals. Additionally, a discussion has been made on the integration of nanocrystal technology with supramolecular design. Marketed cocrystal products and PK studies in human subjects are also reported.

Results: Considering supersaturation and consequent precipitation properties is necessary when evaluating dissolution and bioavailability of cocrystals. Appropriate excipients should be included to control precipitation kinetics and to capture solubility advantage of cocrystals. Beside to solubility, cocrystals may modify membrane permeability of drugs. Therefore, cocrystals can find applications in improving oral bioavailability of poorly permeable drugs. It has been shown that cocrystals may interrupt cellular integrity of cellular monolayers which can raise toxicity concerns. Some of coformers may interact with intestinal absorption of drugs through changing intestinal blood flow, metabolism and inhibiting efflux pumps. Therefore, caution should be taken into account when conducting bioavailability studies. Nanosized cocrystals have shown a high potential towards improving absorption of poorly soluble drugs.

Conclusions: Cocrystals have found their way from the proof-of-principle stage to the clinic. Up to now, at least two cocrystal products have gained approval from regulatory bodies. However, there are remaining challenges on safety, predicting in vivo behavior and revealing real potential of cocrystals in the human.

Natural remedies for non-steroidal anti-inflammatory drug-induced toxicity

The liver is an important organ of the body, which has a vital role in metabolic functions. The non-steroidal anti-inflammatory drug (NSAID), diclofenac causes hepato-renal toxicity and gastric ulcers. NSAIDs are noted to be an agent for the toxicity of body organs. This review has elaborated various scientific perspectives of the toxicity caused by diclofenac and its mechanistic action in affecting the vital organ. This review suggests natural products are better remedies than current clinical drugs against the toxicity caused by NSAIDs. Natural products are known for their minimal side effects, low cost and availability. On the other hand, synthetic drugs pose the danger of adverse effects if used frequently or over a long period. Copyright © 2016 John Wiley & Sons, Ltd.

Celecoxib prevents pressure overload-induced cardiac hypertrophy and dysfunction by inhibiting inflammation, apoptosis and oxidative stress

To explore the effects of celecoxib on pressure overload‐induced cardiac hypertrophy (CH), cardiac dysfunction and explore the possible protective mechanisms. We surgically created abdominal aortic constrictions (AAC) in rats to induce CH. Rats with CH symptoms at 4 weeks after surgery were treated with celecoxib [2 mg/100 g body‐weight(BW)] daily for either 2 or 4 weeks. Survival rate, blood pressure and cardiac function were evaluated after celecoxib treatment. Animals were killed, and cardiac tissue was examined for morphological changes, cardiomyocyte apoptosis, fibrosis, inflammation and oxidative stress. Four weeks after AAC, rats had significantly higher systolic, diastolic and mean blood pressure, greater heart weight and enlarged cardiomyocytes, which were associated with cardiac dysfunction. Thus, the CH model was successfully established. Two weeks later, animals had impaired cardiac function and histopathological abnormalities including enlarged cardiomyocytes and cardiac fibrosis, which were exacerbated 2 weeks later. However, these pathological changes were remarkably prevented by the treatment of celecoxib, independent of preventing hypertension. Mechanistic studies revealed that celecoxib‐induced cardiac protection against CH and cardiac dysfunction was due to inhibition of apoptosis via the murine double mimute 2/P53 pathway, inhibition of inflammation via the AKT/mTOR/NF‐κB pathway and inhibition of oxidative stress via increases in nuclear factor E2‐related factor‐2‐mediated gene expression of multiple antioxidants. Celecoxib suppresses pressure overload‐induced CH by reducing apoptosis, inflammation and oxidative stress.

Deficits in spontaneous burrowing behavior in the rat bilateral monosodium iodoacetate model of osteoarthritis: an objective measure of pain-related behavior and analgesic efficacy

OBJECTIVE

To characterize deficits in burrowing behavior - an ethologically-relevant rodent behavior - in the monosodium iodoacetate (MIA) rat model of osteoarthritis (OA), and the sensitivity of these deficits to reversal by analgesic drugs of both prototypical and novel mechanisms of action. A second objective was to compare the burrowing assay to a spontaneous locomotor activity (sLA) assay.

METHOD

Male Wistar Han rats (200-220 g) received intrarticular (i.a.) injections of MIA or saline for sham animals. A deficit in the amount of sand burrowed from steel tubes filled with 2.5 kg of sand was used as a measure of pain-related behavior, and sensitivity to reversal of these deficits by analgesic drugs was assessed in bilaterally MIA-injected rats.

RESULTS

Bilateral MIA injections induced a significant impairment of burrowing behavior, which was concentration-dependent. The temporal pattern of the deficits was biphasic: a large deficit at 3 days post-injection, resolving by day 14 and returning at the 21 and 28 day time points. At the 3 day time point ibuprofen, celecoxib and an anti-nerve growth factor (NGF) monoclonal antibody (mAb) were able to significantly reinstate burrowing behavior, whereas the fatty acid amide hydrolase (FAAH) inhibitor PF-04457845 and morphine displayed no reversal effect. Morphine impaired burrowing behavior at 3 mg/kg in sham animals. Deficits in rearing frequency in the locomotor activity assay proved irreversible by analgesics.

CONCLUSION

Burrowing behavior provides an objective, non-reflexive read-out for pain-related behavior in the MIA model that has predictive validity in detecting analgesic efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs) and an anti-NGF mAb.

Comparison between 200 mg QD and 100 mg BID oral celecoxib in the treatment of knee or hip osteoarthritis

This network meta-analysis aimed to investigate the effectiveness and safety of 100 mg BID and 200 mg QD oral celecoxib in the treatment of OA of the knee or hip. PubMed, Embase and Cochrane Library were searched through from inception to August 2014. Bayesian network meta-analysis was used to combine direct and indirect evidences on treatment effectiveness and safety. A total of 24 RCTs covering 11696 patients were included. For the comparison in between the two dosage regimens, 100 mg BID oral celecoxib exhibited a greater probability to be the preferred one either in terms of pain intensity or function at the last follow-up time point. For total gastrointestinal (GI) adverse effects (AEs), both of the two dosage regimens demonstrated a higher incidence compared to the placebo group. Further analyses of GI AEs revealed that only 200 mg QD was associated with a significantly higher risk of abdominal pain when compared with placebo. Furthermore, 100 mg BID showed a significantly lower incidence of skin AEs when compared with 200 mg QD and placebo. Maybe 100 mg BID should be considered as the preferred dosage regimen in the treatment of knee or hip OA.

Perioperative celecoxib decreases opioid use in patients undergoing testicular surgery: a randomized, double-blind, placebo controlled trial

PURPOSE

We evaluated the effect of daily perioperative celecoxib on patient reported pain control and opioid use after testicular surgery.

MATERIALS AND METHODS

Men scheduled to undergo elective outpatient microsurgical testicular sperm extraction were prospectively randomized to receive 200 mg celecoxib or placebo twice daily, which was initiated the night before surgery and continued for 6 days thereafter. Using an 11-point visual analog scale, participants self-reported the postoperative pain level and acetaminophen/hydrocodone use for supplemental pain control. We compared differences in pain scores and opioid use between the 2 patient groups using the Student t test with p<0.05 considered significant.

RESULTS

At 1-year interim analysis 35 of 78 eligible participants (45%) had returned the study questionnaire, of whom 34 were included in the final analysis. Of the 34 patients the 16 who received celecoxib had significantly lower postoperative opioid use than those on placebo (6 vs 16 pills, p=0.02). We noted a statistically significant difference in postoperative day 1 and 2 patient reported pain scores (4 vs 6, p<0.05 and 3 vs 5, p=0.03) and opioid use (1 vs 5 pills, p<0.01 and 2 vs 4, p=0.02) seen between the celecoxib and placebo groups, respectively. No study complications were identified. The trial was terminated early based on the results of interim analysis.

CONCLUSIONS

Twice daily celecoxib use started preoperatively significantly decreased patient reported postoperative pain and opioid use, especially in the early postoperative period. A short course of celecoxib is well tolerated and may be effective as part of multimodal postoperative analgesia in patients who undergo testicular surgery for sperm retrieval.

Retrospective evaluation of inpatient celecoxib use after total hip and knee arthroplasty at a Veterans Affairs Medical Center

A retrospective cohort study (1.5 years) was performed to investigate the efficacy of celecoxib vs non-celecoxib use in patient who underwent total knee arthroplasty (TKA) and total hip arthroplasty (THA). Study time frame encompassed a pre and post period of a local policy decision opening access to short-term celecoxib use after TKA/THA. Primary end point was the amount of opioid use during their inpatient stay postprocedure. The TKA (n = 81) and THA (n = 60) groups were analyzed independently. Both celecoxib groups used significantly less opioids during their inpatient stay vs noncelecoxib groups, given in oral morphine milligram equivalents (TKA: 203 vs 337 mg, P = .002; THA: 214 vs 336 mg, P = .005). Other secondary outcome measures showed that the celecoxib groups also reported reduction in pain scores, total as needed (PRN) opioid doses, PRN opioid doses per day, average dose of PRN opioids, total PRN opioids, use of intravenous opioids, and rehabilitation facility admissions (in the TKA group only). Linear regression analysis showed a statistically significant inverse relationship between opioid consumption and age. Short-term celecoxib use after TKA/THA may lead to a reduction in overall opioid use and improved pain scores; however, further studies will be required to validate the results of this study.

Sclareol exhibits anti-inflammatory activity in both lipopolysaccharide-stimulated macrophages and the λ-carrageenan-induced paw edema model

Sclareol (1) is a natural fragrance compound used widely in the cosmetic and food industries. Lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages and the λ-carrageenan-induced edema mouse paw model were applied to examine the anti-inflammatory potential of 1 and its possible molecular mechanisms. The experimental results obtained demonstrated that this compound inhibited cell growth, nitric oxide (NO) production, and the expression of the inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins in LPS-stimulated macrophages. Compound 1 also reduced paw edema, the tissue content of NO, tumor necrosis factor-alpha (TNF-α), malondialdehyde (MDA), iNOS and COX-2 protein expression, and neutrophil infiltration within the tissues after λ-carrageenan stimulation. The present study suggests that the anti-inflammatory mechanisms of 1 might be related to a decrease of inflammatory cytokines and an increase of antioxidant enzyme activity.

Effectiveness of the association micronized N-Palmitoylethanolamine (PEA)-transpolydatin in the treatment of chronic pelvic pain related to endometriosis after laparoscopic assessment: a pilot study

OBJECTIVE

Aim of our study was to evaluate the effectiveness of the association between N-Palmitoylethanolamine and transpolydatin in the management of chronic pelvic pain related to EMS.

STUDY DESIGN

This was a randomized, double-blind, parallel-group, placebo-controlled clinical trial involving 61 subjects, submitted to a first line laparoscopic conservative surgery, who were randomized into 3 groups receiving: group A (n=21) the association N-Palmitoylethanolamine-transpolydatin 400 mg + 40 mg twice a day for 3 months; group B (n=20) the placebo for 3 months; group C (n=20) a single course of Celecoxib 200mg twice a day for 7 consecutive days. Assessments of the severity of pelvic endometriosis (pelvic pain, dysmenorrhoea and dyspareunia) were recorded before and after treatment on a questionnaire and a 10-point VAS. Differences between groups were verified with Kruskal-Wallis ANOVA for non-parametric multiple comparisons.

RESULTS

A marked decrease in dysmenorrhoea, dyspareunia and pelvic pain was observed in all groups, and the association between N-Palmitoylethanolamine and transpolydatin resulted to be more effective than placebo (P<.001). Additionally, the treatment with Celecoxib resulted in a decrease in pelvic pain more effective either than the association N-Palmitoylethanolamine and transpolydatin or placebo.

CONCLUSION

These preliminary results show that the association between micronized N-Palmitoylethanolamine and transpolydatin is effective in the management of pelvic pain related to endometriosis after laparoscopy. Additionally, this association seems to be safe, shows an optimal control of pain and can be used in patients who are unable to receive other therapies.

Celecoxib-induced cholestatic liver failure requiring orthotopic liver transplantation

Selective cyclooxygenase-2 (COX-2) inhibitors are widely used due to their efficacy and good safety profile. However, recent case reports have described varying degrees of liver injuries associated with the use of COX-2 inhibitors. We report the case of a patient who developed acute cholestatic hepatitis progressing to hepatic failure requiring liver transplantation, following a 3-d course of celecoxib for treatment of generalized muscle aches and pains. The clinical presentation, the laboratory data, as well as the liver histopathology were supportive of the putative diagnosis of drug induced liver injury.

3-[1-(4-Sulfamoylphenyl)-5-p-tolyl-1H-pyrazol-3-yl]propanoic acid and 3-[5-(4-bromophenyl)-1-(4-sulfamoylphenyl)-1H-pyrazol-3-yl]propanoic acid-dichloromethane-diethyl ether-water (2/0.72/1/1)

The syntheses of 3-[1-(4-sulfamoylphenyl)-5-p-tolyl-1H-pyrazol-3-yl]propanoic acid, C(19)H(19)N(3)O(4)S, (I), and 3-[5-(4-bromophenyl)-1-(4-sulfamoylphenyl)-1H-pyrazol-3-yl]propanoic acid-dichloromethane-diethyl ether-water (2/0.72/1/1), 2C(18)H(16)BrN(3)O(4)S.0.72CH(2)Cl(2).C(4)H(10)O.H(2)O, (II), are regiospecific. However, correct identification by spectroscopic techniques of the regioisomer formed is not trivial and single-crystal X-ray analysis provided the only means of unambiguous structure determination. Both structures make extensive use of hydrogen bonding and while compound (I) forms a straightforward unsolvated Z' = 1 structure, compound (II) crystallizes as an unusual mixed solvate, with two crystallographically unique molecules of the pyrazole derivative present in the asymmetric unit. The structure of (II) also features Br...Br interactions.

Celecoxib pre-treatment in human colorectal adenocarcinoma patients is associated with gene expression alterations suggestive of diminished cellular proliferation

Cancer cells treated with the cyclooxygenase-2 inhibitor celecoxib show growth inhibition and induced apoptosis. This study was conducted to determine if the same processes are relevant to celecoxib's effects on human colorectal adenocarcinomas treated in vivo. A cohort of 23 patients with primary colorectal adenocarcinomas was randomised to receive a 7-d course of celecoxib (400mg b.i.d.) or no drug prior to surgical resection. Gene expression profiling was performed on resected adenocarcinomas from the cohort of patients. Using fold change (>1.5) and p-value (<0.05) cut-offs, 190 genes were differentially expressed between adenocarcinomas from patients receiving celecoxib and those that did not. The celecoxib pre-treated samples showed decreased expression levels in multiple genes involved in cellular lipid and glutathione metabolism; changes associated with diminished cellular proliferation. Celecoxib pre-treatment for 7 d in vivo is associated with alterations in colorectal adenocarcinoma gene expression which are suggestive of diminished cellular proliferation.