Inhibition of cyclooxygenase-2 by celecoxib reverses tumor-induced wasting

Adipocyte-derived PGE2 is required for intermittent fasting-induced Treg proliferation and improvement of insulin sensitivity

The intermittent fasting (IF) diet has profound benefits for diabetes prevention. However, the precise mechanisms underlying IF's beneficial effects remain poorly defined. Here, we show that the expression levels of cyclooxygenase-2 (COX-2), an enzyme that produces prostaglandins, are suppressed in white adipose tissue (WAT) of obese humans. In addition, the expression of COX-2 in WAT is markedly upregulated by IF in obese mice. Adipocyte-specific depletion of COX-2 led to reduced fractions of CD4+Foxp3+ Tregs and a substantial decrease in the frequency of CD206+ macrophages, an increase in the abundance of γδT cells in WAT under normal chow diet conditions, and attenuation of IF-induced antiinflammatory and insulin-sensitizing effects, despite a similar antiobesity effect in obese mice. Mechanistically, adipocyte-derived prostaglandin E2 (PGE2) promoted Treg proliferation through the CaMKII pathway in vitro and rescued Treg populations in adipose tissue in COX-2-deficient mice. Ultimately, inactivation of Tregs by neutralizing anti-CD25 diminished IF-elicited antiinflammatory and insulin-sensitizing effects, and PGE2 restored the beneficial effects of IF in COX-2-KO mice. Collectively, our study reveals that adipocyte COX-2 is a key regulator of Treg proliferation and that adipocyte-derived PGE2 is essential for IF-elicited type 2 immune response and metabolic benefits.

Repurposing of Antibiotic Sulfisoxazole Inhibits Lipolysis in Pre-Clinical Model of Cancer-Associated Cachexia

Clinical management of cancer-associated cachexia, a multi-organ wasting syndrome, has been challenging without effective treatment strategies. An effective treatment that directly targets cancer-induced wasting is desperately needed to improve the quality of life and the survival of cancer patients. Recently, an antibiotic SFX was shown to have anti-tumour and anti-metastatic effects in mouse models of breast cancer. Hence, in this study, we examined the efficacy of SFX in the treatment of cancer-induced cachexia. C26 cachexic mice models were administered with SFX, and the tumour volume and body weight were regularly measured. Blood glucose, skeletal muscles, and adipose tissue were examined at the endpoint. Contrary to a previous study, SFX did not reduce the tumour volume in mice bearing C26 cells. Administration of SFX neither revealed any survival benefit nor rescued C26 cachectic mice from muscle wasting. Interestingly, SFX administration partially rescued (~10%) tumour-induced weight loss by preserving both the subcutaneous and intestinal fat mass. Together, these results suggest that the administration of SFX could partially rescue cancer-induced weight loss by inhibiting lipolysis. As anti-cachexia therapies are scarce, the results could facilitate the design of combinatorial therapies involving SFX, standard-of-care chemotherapeutics, and drugs that inhibit muscle atrophy for the treatment of cancer cachexia.

Muscle protein breakdown is impaired during immobilization compared to during a subsequent retraining period in older men: no effect of anti-inflammatory medication

Muscle inactivity reduces muscle protein synthesis (MPS), whereas a subsequent period of rehabilitation resistance training (retraining) increases MPS. However, less is known regarding muscle protein breakdown (MPB) during such conditions. Furthermore, nonsteroidal anti-inflammatory drugs (NSAIDs) may have a dampening effect on MPB during periods of inactivity in older individuals. Thus, we measured the average MPB, by use of the deuterated water methodology, during an immobilization period and a subsequent retraining period in older individuals with and without NSAID treatment. Eighteen men (60–80 years: range) were randomly assigned to ibuprofen (1200 mg/d, Ibu) or placebo (Plc). One lower limb was immobilized in a cast for 2 weeks and retrained for 2 weeks, and 2 × 20 g of whey protein was ingested daily during both periods. Besides MPB, the protein expression of different muscle degradation signaling molecules was investigated. MPB was lower during immobilization compared to retraining (p < 0.01). NSAID treatment did not affect the MPB rate during immobilization or retraining (p > 0.05). The protein expression of muscle degradation signaling molecules changed during the study intervention but were unaffected by NSAID treatment. The finding that MPB was lower during immobilization than during retraining indicates that an increased MPB may play an important role in the muscle protein remodeling processes taking place within the initial retraining period. Moreover, NSAID treatment did not significantly influence the MPB rate during 2 weeks of lower limb immobilization or during 2 weeks of subsequent retraining in older individuals.

Adipose mTORC1 Suppresses Prostaglandin Signaling and Beige Adipogenesis via the CRTC2-COX-2 Pathway

Beige adipocytes are present in white adipose tissue (WAT) and have thermogenic capacity to orchestrate substantial energy metabolism and counteract obesity. However, adipocyte-derived signals that act on progenitor cells to control beige adipogenesis remain poorly defined. Here, we show that adipose-specific depletion of Raptor, a key component of mTORC1, promoted beige adipogenesis through prostaglandins (PGs) synthesized by cyclooxygenase-2 (COX-2). Moreover, Raptor-deficient mice were resistant to diet-induced obesity and COX-2 downregulation. Mechanistically, mTORC1 suppressed COX-2 by phosphorylation of CREB-regulated transcription coactivator 2 (CRTC2) and subsequent dissociation of CREB to cox-2 promoter in adipocytes. PG treatment stimulated PKA and promoted differentiation of progenitor cells to beige adipocytes in culture. Ultimately, we show that pharmacological inhibition or suppression of COX-2 attenuated mTORC1 inhibition-induced thermogenic gene expression in inguinal WAT in vivo and in vitro. Our study identifies adipocyte-derived PGs as key regulators of white adipocyte browning, which occurs through mTORC1 and CRTC2.

Comparison of Three Different Treatment Modalities in the Management of Cancer Cachexia

Aims and background

The optimal treatment of cancer cachexia remains unknown. In this study, we compared the efficacy of three different treatment modalities in the management of cancer cachexia.

Methods

Sixty-two assessable cachectic cancer patients were randomized to one of the following three arms: 1) megesterol acetate (MA) plus meloxicam (n = 23); 2) MA plus meloxicam plus oral eicosapentaenoic acid (EPA)-enriched nutritional supplement (n = 21); or 3) meloxicam plus oral EPA-enriched nutritional supplement (n = 18). Treatment duration was 3 months.

Results

The treatment arms were well balanced at baseline. The primary efficacy (body weight and lean body mass) and secondary efficacy (body mass index, quality of life, and serum levels of IL-6 and TNF-α) parameters improved after treatment in all three arms. There were no statistically significant differences between treatment groups in the mean percentage changes in all efficacy parameters from baseline to end of study.

Conclusions

MA plus meloxicam or EPA supplement plus meloxicam may be effective treatment options in the management of cancer cachexia. The combined use of these agents does not provide further advantages.

Drugs of Muscle Wasting and Their Therapeutic Targets

Muscle wasting and weakness such as cachexia, atrophy, and sarcopenia are characterized by marked decreases in the protein content, myonuclear number, muscle fiber size, and muscle strength. This chapter focuses on the recent advances of pharmacological approach for attenuating muscle wasting.A myostatin-inhibiting approach is very intriguing to prevent sarcopenia but not muscular dystrophy in humans. Supplementation with ghrelin is also an important candidate to combat sarcopenia as well as cachexia. Treatment with soy isoflavone, trichostatin A (TSA), and cyclooxygenase 2 (Cox2) inhibitors seems to be effective modulators attenuating muscle wasting, although further systematic research is needed on this treatment in particular concerning side effects.

Novel Browning Agents, Mechanisms, and Therapeutic Potentials of Brown Adipose Tissue

Nonshivering thermogenesis is the process of biological heat production in mammals and is primarily mediated by brown adipose tissue (BAT). Through ubiquitous expression of uncoupling protein 1 (Ucp1) on the mitochondrial inner membrane, BAT displays uncoupling of fuel combustion and ATP production in order to dissipate energy as heat. Because of its crucial role in regulating energy homeostasis, ongoing exploration of BAT has emphasized its therapeutic potential in addressing the global epidemics of obesity and diabetes. The recent appreciation that adult humans possess functional BAT strengthens this prospect. Furthermore, it has been identified that there are both classical brown adipocytes residing in dedicated BAT depots and "beige" adipocytes residing in white adipose tissue depots that can acquire BAT-like characteristics in response to environmental cues. This review aims to provide a brief overview of BAT research and summarize recent findings concerning the physiological, cellular, and developmental characteristics of brown adipocytes. In addition, some key genetic, molecular, and pharmacologic targets of BAT/Beige cells that have been reported to have therapeutic potential to combat obesity will be discussed.

The Janus-Faced Role of Antioxidants in Cancer Cachexia: New Insights on the Established Concepts

Chronic inflammation and excessive loss of skeletal muscle usually occur during cancer cachexia, leading to functional impairment and delaying the cure of cancer. The release of cytokines by tumor promotes the formation of reactive oxygen species (ROS), which in turn regulate catabolic pathways involved in muscle atrophy. ROS also exert a dual role within tumor itself, as they can either promote proliferation and vascularization or induce senescence and apoptosis. Accordingly, previous studies that used antioxidants to modulate these ROS-dependent mechanisms, in cancer and cancer cachexia, have obtained contradictory results, hence the need to gather the main findings of these studies and draw global conclusions in order to stimulate more oriented research in this field. Based on the literature reviewed in this paper, it appears that antioxidant supplementation is (1) beneficial in cancer cachectic patients with antioxidant deficiencies, (2) most likely harmful in cancer patients with adequate antioxidant status (i.e., lung, gastrointestinal, head and neck, and esophageal), and (3) not recommended when undergoing radiotherapy. At the moment, measuring the blood levels of antioxidants may help to identify patients with systemic deficiencies. This approach is simple to realize but could not be a gold standard method for cachexia, as it does not necessarily reflect the redox state in other organs, like muscle.

Understanding cachexia as a cancer metabolism syndrome

Metabolic reprogramming occurs in tumors to foster cancer cell proliferation, survival and metastasis, but as well at a systemic level affecting the whole organism, eventually leading to cancer cachexia. Indeed, as cancer cells rely on external sources of nitrogen and carbon skeleton to grow, systemic metabolic deregulation promoting tissue wasting and metabolites mobilization ultimately supports tumor growth. Cachectic patients experience a wide range of symptoms affecting several organ functions such as muscle, liver, brain, immune system and heart, collectively decreasing patients' quality of life and worsening their prognosis. Moreover, cachexia is estimated to be the direct cause of at least 20% of cancer deaths. The main aspect of cachexia syndrome is the unstoppable skeletal muscle and fat storage wasting, even with an adequate caloric intake, resulting in nutrient mobilization – both directly as lipid and amino acids and indirectly as glucose derived from the exploitation of liver gluconeogenesis – that reaches the tumor through the bloodstream. From a metabolic standpoint, cachectic host develops a wide range of dysfunctions, from increased insulin and IGF-1 resistance to induction of mitochondrial uncoupling proteins and fat tissue browning resulting in an increased energy expenditure and heat generation, even at rest. For a long time, cachexia has been merely considered an epiphenomenon of end-stage tumors. However, in specific tumor types, such as pancreatic cancers, it is now clear that patients present markers of tissue wasting at a stage in which tumor is not yet clinically detectable, and that host amino acid supply is required for tumor growth. Indeed, tumor cells actively promote tissue wasting by secreting specific factors such as parathyroid hormone-related protein and micro RNAs. Understanding the molecular and metabolic mediators of cachexia will not only advance therapeutic approaches against cancer, but also improve patients' quality of life.

The complex liaison between cachexia and tumor burden (Review)

Cachexia is a wasting syndrome that afflicts end-stage cancer patients. Whereas a consensus statement for a definition of cachexia recently has been accomplished, a useful measurement for this condition at present is lacking. The aim of the present review is to discuss the advantage of introducing the measurement of tumor burden for a better overall evaluation of cachexia. Our suggestion ensues from a somewhat novel perspective in the field of infectious disease research where a careful measurement of the pathogen load, between i.e. different host genotypes, leads to the definition of the concept of tolerance to the infectious insult. Indeed tolerance concurs, together the more classical resistance, in maintaining the host reproductive fitness or health state. Noticeably a similar reasoning may apply to tumor biology as well. Whereas the extent of cachexia increases with tumor burden, the relationship between these two correlates of tumor progression fluctuates in a broad range. We have selected from the literature studies in the rodent model where significant variation in the course of the wasting illness during cancer was observed and quantitatively assessed comparing experimental groups marked by different genotype, drug treatment, diet or gender. These studies may be further classified in two categories: the former where the experimental condition associated to milder cachexia is accompanied to a lesser tumor burden, the latter where the inhibition of cachexia results disentangled from the tumor burden, that is the whole number of cancer cells results unchanged or even, paradoxically, is increased. In addition we survey, even in the context of human malignancy, the significance and feasibility of plotting quantitative estimates of cachexia against the whole tumor burden. Ultimately, the principal endeavor of introducing the measurement of tumor burden, in both experimental and clinical oncology, may be to achieve a better assessment of the inter-individual variation in the host vulnerability to cancer cachexia.

Cancer cachexia update in head and neck cancer: Pathophysiology and treatment

The pathophysiology of cancer cachexia remains complex. A comprehensive literature search was performed up to April 2013 using PubMed, the Cochrane Library, Cumulative Index to Nursing and Allied Health Literature, and the Google search engine. In this review, we focus on the different mediators of impaired anabolism and upregulated catabolism that alter the skeletal muscle homeostasis resulting in the wasting of cancer cachexia. We present recent evidence of targeted treatment modalities from clinical trials along with their potential mechanisms of action. We also report on the most current evidence from randomized clinical trials using multimodal treatments in patients with cancer cachexia, but also the evidence from head and neck cancer-specific trials. A more complete understanding of the pathophysiology of the syndrome may lead to more effective targeted therapies and improved outcomes for patients.

Effects of celecoxib and ibuprofen on metabolic disorders induced by Walker-256 tumor in rats

The contribution of anti-inflammatory property of celecoxib in the improvement of metabolic disorders in cancer is unknown. The purpose of this study was to compare the effects of celecoxib and ibuprofen, non-steroidal anti-inflammatory drugs (NSAIDs), on several metabolic changes observed in Walker-256 tumor-bearing rats. The effects of these NSAIDs on the tumor growth were also assessed. Celecoxib or ibuprofen (both at 25 mg/Kg) was administered orally for 12 days, beginning on the day the rats were inoculated with Walker-256 tumor cells. Celecoxib treatment prevented the losses in body mass and mass of retroperitoneal adipose tissue, gastrocnemius, and extensor digitorum longus muscles in tumor-bearing rats. Celecoxib also prevented the rise in blood levels of triacylglycerol, urea, and lactate, the inhibition of peripheral response to insulin and hepatic glycolysis, and tended to attenuate the decrease in the food intake, but had no effect on the reduction of glycemia induced by the tumor. In addition, celecoxib treatment increased the number of Walker-256 cells with signs of apoptosis and the tumor necrosis area and prevented the tumor growth. In contrast, ibuprofen treatment had no effect on metabolic parameters affected by the Walker-256 tumor or tumor growth. It can be concluded that celecoxib, unlike ibuprofen, ameliorated several metabolic changes in rats with Walker-256 tumor due to its anti-tumor effect and not its anti-inflammatory property.

Celecoxib attenuates cachectic events in mice by modulating the expression of vascular endothelial growth factor

Chronic inflammation is one of the main symptoms of cancer cachexia, and cyclooxygenase 2 inhibitors, such as celecoxib, may be beneficial in counteracting the major symptoms of this syndrome. In the current study, celecoxib was orally administered to BALB/c male mice with colon 26 adenocarcinoma. Tumor growth, survival rate, body weight and food intake of the mice with cancer cachexia were recorded during the experiments. The host inflammatory response was assessed by morphological observations and hematoxylin-eosin staining. The serum levels of vascular endothelial growth factor (VEGF), granulocyte-macrophage colony-stimulating factor, interleukin-6 and tumor necrosis factor-α in mice with cancer cachexia were measured by ELISA. Celecoxib administration attenuated the decline in body weight and food intake of mice with cancer cachexia, and improved the survival rate of cachectic mice. Erythrocyte counts and hemoglobin concentration significantly increased in cachectic mice receiving celecoxib compared with control cachectic mice. Notably, celecoxib administration significantly reduced the serum level of VEGF in mice with colon 26 adenocarcinoma, and the cachectic events were also relieved by treatment with a VEGF antibody. The cyclooxygenase 2 inhibitor celecoxib produced positive therapeutic effects in mice with cancer cachexia. This function was regulated at least partly by downregulation of serum levels of VEGF.

Baicalein inhibits DMBA/TPA-induced skin tumorigenesis in mice by modulating proliferation, apoptosis, and inflammation

Baicalein, one of the four major flavanoids extracted from the root of Scutellaria baicalensis, has been shown to exert chemopreventive effect against several cancers, including skin cancer. However, the precise mechanisms remain to be elucidated. In the present study, we investigated the chemopreventive activity of baicalein against 7,12-dimethylbenz[a]anthracene (DMBA)/12-O-tetradecanoylphorbol-13-acetate (TPA)-mediated skin tumorigenesis in C57BL/6 mice. We found that topical treatment with baicalein resulted in a significant inhibitory effect on DMBA/TPA-mediated tumor promotion. Furthermore, we observed that baicalein suppressed cell proliferation and promoted apoptosis in DMBA/TPA-mediated group. Additionally, pretreatment with baicalein inhibited the production of inflammatory cells in DMBA/TPA-induced skin/tumors. Further experiments showed that baicalein reduced TPA-induced skin hyperplasia as well as infiltration of polymorphonuclear leukocytes in the dermis. In conclusion, our data suggest that baicalein inhibits DMBA/TPA-induced skin tumorigenesis by suppressing proliferation and inflammation and promoting apoptosis.

Systemic α-melanocyte-stimulating hormone administration decreases arthritis-induced anorexia and muscle wasting

Rheumatoid cachexia is associated with rheumatoid arthritis and it increases mortality and morbidity. Adjuvant-induced arthritis is an experimental model of rheumatoid arthritis that causes anorexia and muscle wasting. α-Melanocyte-stimulating hormone (α-MSH) has anti-inflammatory actions, and it is able to decrease inflammation in several inflammatory diseases including experimental arthritis. In this study we tested whether systemic α-MSH treatment is able to ameliorate cachexia in arthritic rats. On day 8 after adjuvant injection control and arthritic rats were treated with α-MSH (50 μg/rat ip) twice a day, until day 16 when all rats were euthanized. Arthritis decreased food intake, but it increased hypothalamic expression of neuropeptide Y (NPY) and Agouti-related peptides (AgRP) as well as interleukin-1β (IL-1β) and cyclooxygenase-2 (COX-2) mRNA. In arthritic rats, α-MSH decreased the external signs of arthritis and increased food intake (P < 0.01). In addition, α-MSH decreased hypothalamic expression of IL-1β, COX-2, proopiomelanocortin, and prohormone-converting (PC) enzymes PC1/3 and PC2 mRNA in arthritic rats. In control rats, α-MSH did not modify food intake or hypothalamic expression of aforementioned mRNA. α-MSH prevented arthritis-induced increase in gastrocnemius COX-2, muscle-specific RING-finger protein-1 (MuRF1), and atrogin-1 expression, and it increased fast myofiber size. In conclusion our data show that in arthritic rats peripheral α-MSH treatment has an anti-cachectic action increasing food intake and decreasing muscle wasting.

Cancer-induced anorexia in tumor-bearing mice is dependent on cyclooxygenase-1

It is well-established that prostaglandins (PGs) affect tumorigenesis, and evidence indicates that PGs also are important for the reduced food intake and body weight loss, the anorexia-cachexia syndrome, in malignant cancer. However, the identity of the PGs and the PG producing cyclooxygenase (COX) species responsible for cancer anorexia-cachexia is unknown. Here, we addressed this issue by transplanting mice with a tumor that elicits anorexia. Meal pattern analysis revealed that the anorexia in the tumor-bearing mice was due to decreased meal frequency. Treatment with a non-selective COX inhibitor attenuated the anorexia, and also tumor growth. When given at manifest anorexia, non-selective COX-inhibitors restored appetite and prevented body weight loss without affecting tumor size. Despite COX-2 induction in the cerebral blood vessels of tumor-bearing mice, a selective COX-2 inhibitor had no effect on the anorexia, whereas selective COX-1 inhibition delayed its onset. Tumor growth was associated with robust increase of PGE(2) levels in plasma - a response blocked both by non-selective COX-inhibition and by selective COX-1 inhibition, but not by COX-2 inhibition. However, there was no increase in PGE(2)-levels in the cerebrospinal fluid. Neutralization of plasma PGE(2) with specific antibodies did not ameliorate the anorexia, and genetic deletion of microsomal PGE synthase-1 (mPGES-1) affected neither anorexia nor tumor growth. Furthermore, tumor-bearing mice lacking EP(4) receptors selectively in the nervous system developed anorexia. These observations suggest that COX-enzymes, most likely COX-1, are involved in cancer-elicited anorexia and weight loss, but that these phenomena occur independently of host mPGES-1, PGE(2) and neuronal EP(4) signaling.

Non-steroidal anti-inflammatory treatment in cancer cachexia: a systematic literature review

BACKGROUND

There are no established treatments for cachexia. Recently it has been suggested that the evidence for non-steroidal anti-inflammatory (NSAID) treatment is sufficient to support its regular clinical use. Primary objective in this systematic review was to assess efficacy and safety of NSAID treatment in improving body weight and muscle mass in patients with cancer cachexia. Secondary objectives were to assess whether this treatment could improve other cachexia domains such as anorexia and food intake, catabolic drive and function.

MATERIAL AND METHODS

A systematic literature review of PubMed, EMBASE and Cochrane Central register of controlled trials database was carried out using both text words and MeSH/EMTREE terms.

RESULTS

Thirteen studies were included; all but two trials showed either improvement or stabilization in weight or lean body mass. Seven studies were without a comparator. Studies are generally small and a few are methodologically flawed, often due to multiple outcomes with excess risk of false positives.

CONCLUSION

NSAIDs may improve weight in cancer patients with cachexia, and there is some evidence on effect on physical performance, self-reported quality of life and inflammatory parameters. Evidence is too frail to recommend NSAID for cachexia outside clinical trials. This is supported by the known side effects of NSAIDs, even though the reviewed literature report almost negligible toxicity.

Dermal microdialysis technique to evaluate the trafficking of surface-modified lipid nanoparticles upon topical application

PURPOSE

To evaluate the skin pharmacokinetics and tissue distribution of cell penetrating peptides (CPP) modified nano-structured lipid carrier (NLC) using an in vivo dermal microdialysis (MD) technique.

METHODS

Celecoxib (Cxb) encapsulated NLCs (CXBN), CPP modified CXBN (CXBN-CPP) and Cxb-Solution (CXBS) formulations were prepared and tested for in vitro skin distribution. MD was used to assess pharmacokinetic parameters of Cxb after topical application of Cxb formulations. The effect of pre-treatment with Cxb formulations was evaluated for expression of prostaglandin-E2 (PGE(2)) and Interleukin-6 (IL-6) after exposure of xylene using MD. Allergic contact dermatitis (ACD) model was used to confirm in vivo therapeutic response of Cxb formulations.

RESULTS

The cumulative permeation of Cxb in MD dialysate after 24 h for CXBN-CPP was significantly higher (p < 0.001) than CXBN and CXBS. Further, pre-treatment with CXBN-CPP significantly inhibited PGE(2) and IL-6 expression compared to CXBS and CXBN (p < 0.001). In ACD model, CXBN-CPP showed significant reduction (p < 0.001) in ear thickness compared to controls.

CONCLUSIONS

Surface modification of NLC with CPPs can enhance the skin permeation of Cxb and MD can be used to investigate pharmacokinetics of Cxb nanoparticles in the skin.

Targeting protein synthesis in a Myc/mTOR-driven model of anorexia-cachexia syndrome delays its onset and prolongs survival

Anorexia-cachexia syndrome (ACS) is a major determinant of cancer-related death that causes progressive body weight loss due to depletion of skeletal muscle mass and body fat. Here, we report the development of a novel preclinical murine model of ACS in which lymphomas harbor elevated Myc and activated mTOR signaling. The ACS phenotype in this model correlated with deregulated expression of a number of cytokines, including elevated levels of interleukin-10 which was under the direct translational control of mTOR. Notably, pharmacologic intervention to impair protein synthesis restored cytokine production to near-normal levels, delayed ACS progression, and extended host survival. Together, our findings suggest a new paradigm to treat ACS by strategies which target protein synthesis to block the production of procachexic factors.

A randomised feasibility study of EPA and Cox-2 inhibitor (Celebrex) versus EPA, Cox-2 inhibitor (Celebrex), resistance training followed by ingestion of essential amino acids high in leucine in NSCLC cachectic patients--ACCeRT study

Background

Cancer cachexia is a syndrome of progressive weight loss. Non-small cell lung cancer patients experience a high incidence of cachexia of 61%. Research into methods to combat cancer cachexia in various tumour sites has recently progressed to the combination of agents.

The combination of the anti-cachectic agent Eicosapentaenoic acid (EPA) and the cyclo-oxygenase-2 (COX-2) inhibitor celecoxib has been tested in a small study with some benefit. The use of progressive resistance training (PRT) followed by the oral ingestion of essential amino acids (EAA), have shown to be anabolic on skeletal muscle and acceptable in older adults and other cancer groups.

The aim of this feasibility study is to evaluate whether a multi-targeted approach encompassing a resistance training and nutritional supplementation element is acceptable for lung cancer patients experiencing cancer cachexia.

Methods/Design

Auckland's Cancer Cachexia evaluating Resistance Training (ACCeRT) is an open label, prospective, randomised controlled feasibility study with two parallel arms. All patients will be treated with EPA and the COX-2 inhibitor celecoxib on an outpatient basis at the study site. In the experimental group patients will participate in PRT twice a week, followed by the ingestion of essential amino acids high in leucine. A total of 21 patients are planned to be enrolled. Patients will be randomised using 1:2 ratio with 7 patients enrolled into the control arm, and 14 patients into the treatment arm. The primary endpoint is the acceptability of the above multi-targeted approach, determined by an acceptability questionnaire.

Discussion

To our knowledge ACCeRT offers for the first time the opportunity to investigate the effect of stimulating the anabolic skeletal muscle pathway with the use of PRT along with EAA alongside the combination of EPA and celecoxib in this population.

Trial registration

Netherlands Trial Register (NTR): ACTRN12611000870954

Cancer cachexia therapy: a key weapon in the fight against cancer

PURPOSE OF REVIEW

Cachexia affects millions of cancer patients around the world. Though its causes are poorly understood, its devastating impact on the patient and their loved ones underscore the urgency of this unmet medical need. Recent research efforts suggest multiple body systems are dysregulated in cachexia, not only increasing the challenge in effectively treating the disease but also expanding the opportunities for intervention.

RECENT FINDINGS

Agents as diverse as anti-inflammatory monoclonal antibodies and novel anabolic small molecules are under clinical evaluation for their ability to prevent and treat wasting. The therapies evaluated to date range in their ability to improve appetite, mitigate weight loss and reverse undesirable changes in body composition and physical function.

SUMMARY

An increased understanding of cancer cachexia, both mechanistically and its impact on cancer patients' struggle with their disease, has resulted in diverse therapeutic concepts. Recent clinical efforts demonstrate progress with novel therapies but fall short of effectively treating most cachectic patients and highlight a clear need for further research. Given the inherent heterogeneity of cancer patients and the significant impact of muscle wasting on morbidity and mortality, continued research efforts are critical in developing effective therapies to prevent and treat cancer cachexia.

Pharmacological modulation by celecoxib of cachexia associated with experimental arthritis and atherosclerosis in rabbits

BACKGROUND AND PURPOSE

Non-steroidal anti-inflammatory drugs improve inflammatory cachexia in several conditions. Thus, we have explored inhibition of cyclooxygenase-2 (COX-2) in an experimental model of rheumatoid cachexia in rabbits.

EXPERIMENTAL APPROACH

Chronic arthritis was induced in immunized rabbits by repeated intra-articular injections of ovalbumin. To increase the degree of systemic inflammation and also to induce atherosclerotic lesions, the animals were fed a hyperlipidaemic diet (2% cholesterol and 6% peanut oil) and were given an endothelial injury of the femoral artery. Rabbits were randomized to receive the COX-2 inhibitor celecoxib (10 mg·kg⁻¹ ·day⁻¹) or no treatment. After 4 weeks, sera, peripheral mononuclear cells and vessel specimens were collected.

KEY RESULTS

Inhibition of COX-2 by celecoxib modulated the systemic inflammatory response and increased total cholesterol and triglyceride levels. Celecoxib also minimized weight loss and prevented serum albumin fall. At a vascular level, celecoxib reduced COX-2 protein in the femoral arterial wall, but did not modify size or the macrophage infiltration of femoral lesions nor the percentage of rabbits with spontaneous aortic plaques.

CONCLUSIONS AND IMPLICATIONS

Our animal model induced a severe inflammatory cachexia, comparable to that of persistently active rheumatoid arthritis. The inhibition of COX-2 by celecoxib improves this state, suggesting that COX products play an important role in its development, without affecting the development or the progression of vascular lesions. Overall, these results suggest that celecoxib might be considered as a new therapeutic tool for the treatment of rheumatoid cachexia.

Pathophysiology and treatment of inflammatory anorexia in chronic disease

Decreased appetite and involuntary weight loss are common occurrences in chronic disease and have a negative impact on both quality of life and eventual mortality. Weight loss in chronic disease comes from both fat and lean mass, and is known as cachexia. Both alterations in appetite and body weight loss occur in a wide variety of diseases, including cancer, heart failure, renal failure, chronic obstructive pulmonary disease and HIV. An increase in circulating inflammatory cytokines has been implicated as a uniting pathogenic mechanism of cachexia and associated anorexia. One of the targets of inflammatory mediators is the central nervous system, and in particular feeding centers in the hypothalamus located in the ventral diencephalon. Current research has begun to elucidate the mechanisms by which inflammation reaches the hypothalamus, and the neural substrates underlying inflammatory anorexia. Research into these neural mechanisms has suggested new therapeutic possibilities, which have produced promising results in preclinical and clinical trials. This review will discuss inflammatory signaling in the hypothalamus that mediates anorexia, and the opportunities for therapeutic intervention that these mechanisms present.

Differential effects of nitric oxide on blood-brain barrier integrity and cerebral blood flow in intracerebral C6 gliomas

Nitric oxide (NO) signaling in tumors and endothelial cells regulates vascular permeability and blood flow and therefore influences tumor uptake and response to therapeutic compounds. As delivery and efficacy of chemotherapy is impaired in CNS neoplasms due to a partially intact blood-brain barrier (BBB), we studied the effects of NO released by the short-acting NO donor disodium 1-[2-(carboxylato)pyrrolidin-1-yl]diazen-1-ium-1,2-diolate methanolate (PROLI/NO) on BBB integrity and blood flow in C6 gliomas using [¹⁴C]-aminoisobutyric acid (AIB) and [¹⁴C]-iodoantipyrine quantitative autoradiography. PROLI/NO selectively increased intratumoral uptake of [¹⁴C]AIB and [¹⁴C]sucrose when given as a 3-minute intracarotid infusion or a 15-minute i.v. infusion (AIB: tumor, K₁ = 68.7 ± 3.2 vs 24.9 ± 0.9 µL g⁻¹ min⁻¹, P < .0001; sucrose, K₁ = 16.9 ± 0.9 vs 11.5 ± 0.9 µL g⁻¹ min⁻¹, P = .0007). This effect was achieved without significant changes in cerebral and tumor blood flow or arterial blood pressure, which indicates that the effect on vascular permeability is independent of changes in vascular tone induced by NO. This effect was mediated by activation of the NO/3',5'-cyclic guanosine monophosphate (cGMP) pathway, as it was blocked by guanylate cyclase inhibition by LY83583 and reproduced by the delivery of 8-bromoguanosine 5'-monophosphate or inhibition of cGMP degradation by the phosphodiesterase inhibitor zaprinast. Inhibition of inducible NO synthase by aminoguanidine or cyclooxygenase inhibition by indometacin or dexamethasone did not reduce the blood-tumor barrier (BTB) response to PROLI/NO. PROLI/NO, and perhaps other NO-donating compounds, can be used to selectively increase BTB permeability in gliomas through the NO/cGMP pathway at doses that do not cause unwanted vasodilatory changes in blood flow and that do not affect the systemic circulation.

Cyclooxygenase-2 controls energy homeostasis in mice by de novo recruitment of brown adipocytes

Obesity results from chronic energy surplus and excess lipid storage in white adipose tissue (WAT). In contrast, brown adipose tissue (BAT) efficiently burns lipids through adaptive thermogenesis. Studying mouse models, we show that cyclooxygenase (COX)-2, a rate-limiting enzyme in prostaglandin (PG) synthesis, is a downstream effector of beta-adrenergic signaling in WAT and is required for the induction of BAT in WAT depots. PG shifted the differentiation of defined mesenchymal progenitors toward a brown adipocyte phenotype. Overexpression of COX-2 in WAT induced de novo BAT recruitment in WAT, increased systemic energy expenditure, and protected mice against high-fat diet-induced obesity. Thus, COX-2 appears integral to de novo BAT recruitment, which suggests that the PG pathway regulates systemic energy homeostasis.

Phase II nonrandomized study of the efficacy and safety of COX-2 inhibitor celecoxib on patients with cancer cachexia

Chronic inflammation is one of the main features of cancer cachexia. Experimental and clinical studies showed that cyclooxygenase-2 inhibitors, such as celecoxib, may be beneficial in counteracting major symptoms of this devastating syndrome. We carried out a prospective phase II clinical trial to test the safety and effectiveness of an intervention with the COX-2 inhibitor celecoxib (300 mg/day for 4 months) on key variables of cachexia (lean body mass, resting energy expenditure, serum levels of proinflammatory cytokines, and fatigue) in patients with advanced cancer at different sites. A sample of 24 patients was enrolled from January to December 2008 and all were deemed assessable. A significant increase of lean body mass and a significant decrease of TNF-alpha were observed. Moreover, an improvement of grip strength, quality of life, performance status, and Glasgow prognostic score was shown. There were no grade 3/4 toxicities. Patient compliance was very good; no patient had to reduce the celecoxib dosage nor interrupt treatment. Our results showed that the COX-2 selective inhibitor celecoxib is an effective single agent for the treatment of cancer cachexia. Although the treatment of cancer cachexia, a multifactorial syndrome, is more likely to yield success with a multitargeted approach; in the present study, we were able to show that a treatment, such as celecoxib, addressing a single target, albeit very important as chronic inflammation, could have positive effects. Therefore, phase III clinical trials are warranted to test the efficacy and safety of celecoxib.

Cyclooxygenase-2 inhibitors and antioxidants in the treatment of cachexia

PURPOSE OF REVIEW

Cancer cachexia is increasingly becoming a critical component in the comprehensive approach to cancer patients influencing morbidity, mortality and quality of life. Therefore its pathophysiology and the main contributing factors have been investigated with the aim of developing effective therapies. Reported findings highlight the role of chronic inflammation and oxidative stress in the onset of cancer cachexia.

RECENT FINDINGS

Chronic inflammation, one of the main features of cancer cachexia, triggers the overproduction of proinflammatory cytokines playing a major role in the pathogenesis of systemic symptoms of cachexia; therefore, antiinflammatory drugs such as cyclooxygenase-2 inhibitors could break the 'vicious circle' leading to the onset and worsening of this devastating syndrome. Likewise, oxidative stress, almost always accompanying cancer cachexia, may be counteracted by effective antioxidant treatments. The most relevant recent clinical approaches addressing these targets are reported.

SUMMARY

Fairly advanced clinical data on efficacy of cyclooxygenase-2 inhibitors and antioxidants in advanced cancer patients are promising, but the best way to administer and combine them with other agents, the optimal dose and timing remain uncertain. However, because cachexia is a multifactorial syndrome, therapeutic approaches targeting a single contributing factor may be inadequate. A rational treatment should thus be multitargeted addressing all key contributing factors.

Prostaglandins and sickness behavior: old story, new insights

Previous evidence has shown that prostaglandins play a key role in the development of sickness behavior observed during inflammatory states. In particular, prostaglandin E2 (PGE2) is produced in the brain by a variety of inflammatory signals such as endotoxins or cytokines. Its injection has been also shown to induce symptoms of sickness behavior. The role of cyclooxygenase enzymes (COX), the rate-limiting enzymes converting arachidonic acid into prostaglandins, in sickness behavior has been extensively studied, and it has been demonstrated that strategies aiming at inhibiting these enzymes limit anorexia, body weight loss and fever in animals with inflammatory diseases. However, inhibiting COX activity may lead to negative gastric or cardiovascular effects, since COX enzymes play a role in the synthesis of others prostanoids with various and sometimes contrasting properties. Recently, prostaglandin E synthases (PGES), which specifically catalyze the final step of PGE2 biosynthesis, were characterized. Among these enzymes, the microsomal prostaglandin E synthase-1 (mPGES-1) was of a particular interest since it was shown to be up-regulated by inflammatory signals in a variety of cell types. Moreover, mPGES-1 was shown to be crucial for correct immune-to-brain communication and induction of fever and anorexia by pro-inflammatory agents. This review takes stock of previous knowledge and recent advances in understanding the role of prostaglandins and of their specific synthesizing enzymes in the molecular mechanisms underlying sickness behavior. The review concludes with a short summary of key questions that remain to be addressed and points out therapeutic developments in this research field.

Dietary stearidonic acid is a long chain (n-3) polyunsaturated fatty acid with potential health benefits

The therapeutic and health-promoting effects of (n-3) long-chain PUFA (LCPUFA) from fish are well known, although these same benefits may not be shared by their precursor, alpha-linolenic acid (ALA). World-wide agencies and scientific organizations (i.e. FDA, AHA, International Society for the Study of Fatty Acids and Lipids, Institute of Medicine, WHO, etc.) have made similar dietary recommendations for (n-3) LCPUFA; however, due to concerns regarding the safety of consuming fish, alternative sources of (n-3) LCPUFA are being investigated. One such lipid is stearidonic acid (SDA), a naturally occurring (n-3) PUFA that may have similar biological properties to eicosapentaenoic acid (EPA), a major (n-3) PUFA in fish oil. Existing and novel plant sources rich in SDA are being cultivated and promoted as potential alternatives to marine-based (n-3) PUFA. This critical review provides a direct comparison of SDA with other dietary (n-3) PUFA under similar experimental conditions. The comparative results suggest that SDA shares many of the biological effects of (n-3) LCPUFA and functions most similarly to dietary EPA compared with ALA when consumed in a typical Western diet. Therefore, although SDA may not replace fish as a major dietary source of (n-3) LCPUFA, it could become a prominent surrogate for EPA in the commercial development of foods fortified with (n-3) PUFA.

mPGES-1 knock-out mice are resistant to cancer-induced anorexia despite the absence of central mPGES-1 up-regulation in wild-type anorexic mice

Anorexia-cachexia syndrome is a very common symptom observed in individuals affected by chronic inflammatory diseases. The present study was designed to address the possible involvement of the inducible microsomal prostaglandin E synthase-1 (mPGES-1) in the hypopaghia observed during these pathological states. To this end, we used a model of cancer-induced anorexia and we report here that despite the absence of up-regulation of the mPGES-1 enzyme within the brain during anorexia-cachexia syndrome, mPGES-1 knock-out mice exhibit resistance to tumor-induced anorexia and maintain their body mass.

Results of a pilot study of the effects of celecoxib on cancer cachexia in patients with cancer of the head, neck, and gastrointestinal tract

BACKGROUND

Animal models suggest that cyclooxygenase-2 (COX-2) inhibitors may be beneficial in suppressing cancer cachexia. We investigated the effect of short-course celecoxib on body composition, inflammation, and quality of life (QOL) in patients with cancer cachexia in a phase II clinical pilot trial.

METHODS

Eleven cachectic patients with head and neck or gastrointestinal cancer were randomly assigned to receive placebo or celecoxib for 21 days while awaiting the initiation of cancer therapy. Body composition, resting energy expenditure, QOL, physical function, and inflammatory markers were measured on days 1 and 21.

RESULTS

Patients receiving celecoxib experienced statistically significant increases in weight and body mass index (BMI), while patients receiving placebo experienced weight loss and a decline in BMI. Patients receiving celecoxib also had increases in QOL scores.

CONCLUSIONS

Cachectic patients receiving celecoxib gained weight, experienced increased BMI, and demonstrated improved QOL scores. Compliance was good and no adverse events were seen.

Effects of eicosapentaenoic and docosahexaenoic n-3 fatty acids from fish oil and preferential Cox-2 inhibition on systemic syndromes in patients with advanced lung cancer

Under the common denomination of Systemic Immune-Metabolic Syndrome (SIMS), we grouped many symptoms that share a similar pathophysiologic background. SIMS is the result of the dysfunctional interaction of tumor cells, stroma cells, and the immune system, leading to the release of cytokines and other systemic mediators such as eicosanoids. SIMS includes systemic syndromes such as paraneoplastic hemopathies, hypercalcemia, coagulopathies, fatigue, weakness, cachexia, chronic nausea, anorexia, and early satiety among others. Eicosapentaenoic and docosahexaenoic n-3 fatty acids from fish oil can help in the management of persistent chronic inflammatory states, but treatment's compliance is generally poor. Preferentially, Cox-2 inhibition can create a favorable pattern of cytokines by decreasing the production of certain eicosanoids, although their role in SIMS is unknown. The aim of this study was to test the hypothesis that by modulating systemic inflammation through an eicosanoid-targeted approach, some of the symptoms of the SIMS could be controlled. We exclusively evaluated 12 patients for compliance. Patients were assigned 1 of the 4 treatment groups (15-, 12-, 9-, or 6-g dose, fractionated every 8 h). For patients assigned to 15 and 12 doses, the overall compliance was very poor and unsatisfactory for patients receiving the 9-g dose. The maximum tolerable dose was calculated to be around 2 capsules tid (6 g of fish oil per day). A second cohort of 22 patients with advanced lung cancer and SIMS were randomly assigned to receive either fish oil, 2 g tid, plus placebo capsules bid (n = 12) or fish oil, 2 g tid, plus celecoxib 200 mg bid (n = 10). All patients in both groups received oral food supplementation. After 6 wk of treatment, patients receiving fish oil + placebo or fish oil + celecoxib showed significantly more appetite, less fatigue, and lower C-reactive protein (C-RP) values than their respective baselines values (P < 0.02 for all the comparisons). Additionally, patients in the fish oil + celecoxib group also improved their body weight and muscle strength compared to baseline values (P < 0.02 for all the comparisons). Comparing both groups, patients receiving fish oil + celecoxib showed significantly lower C-RP levels (P = 0.005, t-test), higher muscle strength (P = 0.002, t-test) and body weight (P = 0.05, t-test) than patients receiving fish oil + placebo. The addition of celecoxib improved the control of the acute phase protein response, total body weight, and muscle strength. Additionally, the consistent nutritional support used in our patients could have helped to maximize the pharmacological effects of fish oil and/or celecoxib. This study shows that by modulating the eicosanoid metabolism using a combination of n-3 fatty acids and cyclooxygenase-2 inhibitor, some of the signs and symptoms associated with a SIMS could be ameliorated.

Fatigue in palliative care patients -- an EAPC approach

Fatigue is one of the most frequent symptoms in palliative care patients, reported in .80% of cancer patients and in up to 99% of patients following radio- or chemotherapy. Fatigue also plays a major role in palliative care for noncancer patients, with large percentages of patients with HIV, multiple sclerosis, chronic obstructive pulmonary disease or heart failure reporting fatigue. This paper presents the position of an expert working group of the European Association for Palliative Care (EAPC), evaluating the available evidence on diagnosis and treatment of fatigue in palliative care patients and providing the basis for future discussions. As the expert group feels that culture and language influence the approach to fatigue in different European countries, a focus was on cultural issues in the assessment and treatment of fatigue in palliative care. As a working definition, fatigue was defined as a subjective feeling of tiredness, weakness or lack of energy. Qualitative differences between fatigue in cancer patients and in healthy controls have been proposed, but these differences seem to be only an expression of the overwhelming intensity of cancer-related fatigue. The pathophysiology of fatigue in palliative care patients is not fully understood. For a systematic approach, primary fatigue, most probably related to high load of proinflammatory cytokines and secondary fatigue from concurrent syndromes and comorbidities may be differentiated. Fatigue is generally recognized as a multidimensional construct, with a physical and cognitive dimension acknowledged by all authors. As fatigue is an inherent word only in the English and French language, but not in other European languages, screening for fatigue should include questions on weakness as a paraphrase for the physical dimension and on tiredness as a paraphrase for the cognitive dimension. Treatment of fatigue should include causal interventions for secondary fatigue and symptomatic treatment with pharmacological and nonpharmacological interventions. Strong evidence has been accumulated that aerobic exercise will reduce fatigue levels in cancer survivors and patients receiving cancer treatment. In the final stage of life, fatigue may provide protection and shielding from suffering for the patient and thus treatment may be detrimental. Identification of the time point, where treatment of fatigue is no longer indicated is important to alleviate distress at the end of life.

Interleukin-6 and cachexia in ApcMin/+ mice

The Apc(Min/+) mouse has a mutation in the Apc tumor suppressor gene and develops intestinal polyps, beginning at 4 wk of age. This mouse develops cachexia by 6 mo, characterized by significant loss of muscle and fat tissue. The purpose of the present study was to determine the role of circulating interleukin-6 (IL-6) and the polyp burden for the development of cachexia in Apc(Min/+) mice. At 26 wk of age, mice exhibiting severe cachectic symptoms had a 61% decrease in gastrocnemius muscle weight, complete loss of epididymal fat, a 10-fold increase in circulating IL-6 levels, and an 89% increase in intestinal polyps compared with mildly cachectic animals. Apc(Min/+)/IL-6(-/-) mice did not lose gastrocnemius muscle mass or epididymal fat pad mass while overall polyp number decreased by 32% compared with Apc(Min/+) mice. Plasmid-based IL-6 overexpression in Apc(Min/+)/IL-6(-/-) mice led to a decrease in gastrocnemius muscle mass and epididymal fat pad mass and increased intestinal polyp burden. IL-6 overexpression did not induce cachexia in non-tumor-bearing mice. These data demonstrate that IL-6 is necessary for the onset of adipose and skeletal muscle wasting in the Apc(Min/+) mouse and that circulating IL-6 can regulate Apc(Min/+) mouse tumor burden.

Action of Celecoxib on Hepatic Metabolic Changes Induced by the Walker-256 Tumour in Rats

The purpose of the present work was to investigate the influence of celecoxib on some hepatic metabolic parameters affected by the Walker-256 tumour in rats. Celecoxib was administered daily (5-50 mg/kg body weight) beginning at the day in which the tumour cells were inocculated. At day 14, the liver was isolated and perfused in order to measure alanine transformation, glycolysis and arginine transformation. Maximal reduction of tumour growth (75%), accompanied by an almost normal weight gain, was attained with a celecoxib dose of 12.5 mg/kg. Diminution of glucose utilization (glycolysis) and inhibition of gluconeogenesis and ureogenesis from alanine caused by the tumor were totally reversed by celecoxib. Oxygen uptake by the liver was also normalized by the drug. Hepatic arginine transformation, which is normally enhanced in rats bearing the Walker-256 tumour, remained elevated in celecoxib-treated animals. It was concluded that preservation of gluconeogenesis and normalization of hepatic glucose utilization can explain, partly at least, the clinical improvement of cancer patients treated with the drug. The lack of action of celecoxib on arginine hydrolysis might indicate that reduction in polyamine synthesis is not a factor contributing to the diminished tumour growth.

Involvement of cyclooxygenase-2 in the tumor site-dependent production of parathyroid hormone-related protein in colon 26 carcinoma

It has been shown that in the mouse colon 26 tumor model, tumors grown in the subcutis (subcutis colon 26) caused early onset of cachectic syndromes, whereas those in the liver (liver colon 26) did not. Both interleukin (IL)-6 and parathyroid hormone-related protein (PTHrP) were involved in the development of cachectic syndromes in this tumor model. However, whether expression of PTHrP and IL-6 is differently regulated in the tumor microenvironment is unclear. In the present study, culturing the colon 26 cells under different conditions in vitro revealed that IL-6 production was increased by monolayer culture under a low-glucose condition but not by spheroid culture. In contrast, PTHrP production was increased by spheroid culture but not by monolayer culture, even under a low-glucose condition. Gene expression profiling revealed that the expression of cyclooxygenase (COX)-2 was up-regulated in both subcutis colon 26 and spheroid cultures, and that COX-2 inhibitor NS-398 suppressed PTHrP production in spheroid cultures. Furthermore, administration of NS-398 decreased the PTHrP level without affecting the tumor growth in mice bearing subcutis colon 26. These results demonstrate that production of PTHrP and IL-6 largely depends on the microenvironments in which tumors are developed or metastasized and that up-regulation of COX-2 in a necrobiotic environment leads to PTHrP production, thereby causing cachectic syndromes.

Melanocortin interventions in cachexia: how soon from bench to bedside?

PURPOSE OF REVIEW

Cachexia is a condition of anorexia and wasting that accompanies many diseases including cancer, heart failure, and renal failure. One key center that is probably involved in the propagation of symptoms of cachexia is the melanocortin system in the hypothalamus and brainstem. This review focuses on cachexia treatment interventions that act via melanocortin antagonism, by direct or indirect means.

RECENT FINDINGS

Recent reports include a description of the physiology of the melanocortin system and its responsiveness to inflammatory cytokines. Regarding treatment potential, multiple reports describe the effectiveness of small molecule antagonists of the melanocortin-4 receptor in animal models of cachexia. These melanocortin antagonists, given by peripheral injection, improve food intake and lean body mass retention in the setting of cancer and renal failure. Additional reports provide evidence of melanocortin antagonism following treatment of cachexia using ghrelin and eicosonoic acid.

SUMMARY

Cachexia is a serious condition that accompanies various disease states and currently does not have effective treatments. The melanocortin system may play a direct role in producing symptoms of cachexia, making antagonism of this system a logical objective for ameliorating these symptoms. Thus far, however, no data on human application have been published.

Cancer cachexia syndrome in head and neck cancer patients: part I. Diagnosis, impact on quality of life and survival, and treatment

BACKGROUND

Cancer cachexia is a debilitating, wasting condition that affects many cancer patients, including those with head and neck cancer. The overall incidence of cancer cachexia is quite high for some types of cancer, and cachexia will be the main cause of death for more than 20% of all cancer patients. This syndrome uniquely challenges patients with head and neck cancer. This article outlines the diagnosis of cancer cachexia, reviews its impact on patient quality of life (QOL) and survival, and updates the reader on potential therapies that may suppress it.

METHODS

A comprehensive literature search was performed using PubMed of the National Library of Medicine, which includes more than 15 million citations back to the 1950s. The Cochrane Library and Google search engine were used as well.

RESULTS

This syndrome differs significantly from starvation, and thus accurate and timely diagnosis is essential. Nutritional therapy alone is insufficient. Current management strategies include corticosteroids and megesterol acetate, in conjunction with nutritional therapy. Future strategies may include nutraceuticals, omega-3 fatty acids, inflammatory antagonists, and other targeted treatments.

CONCLUSIONS

Because cancer cachexia differs significantly from starvation, nutritional supplementation must be used in conjunction with other anti-cachexia agents to reverse the chronic systemic inflammatory state and the effects of circulating tumor-derived factors seen in cachexia. Careful identification of patients at risk and those suffering from this syndrome will lead to better outcomes and treatments. Ultimately, more research is needed to better treat this devastating condition.

Experimental arthritis inhibits the insulin-like growth factor-I axis and induces muscle wasting through cyclooxygenase-2 activation

Chronic arthritis induces cachexia associated with an inhibition of the growth hormone (GH)-insulin-like growth factor-I (IGF-I) system and an activation of the E3 ubiquitin-ligating enzymes muscle atrophy F-box (MAFbx) and muscle Ring finger 1 (MuRF1) in the skeletal muscle. The aim of this work was to study the role of cyclooxygenase (COX)-2 in chronic arthritis-induced cachexia. Arthritis was induced in rats by Freund's adjuvant injection, and the effects of two COX inhibitors (indomethacin, a nonspecific inhibitor, and meloxicam, a selective COX-2 inhibitor on pituitary GH and on liver and serum IGF-I levels) were tested. Arthritis decreased body weight gain and GH and liver IGF-I gene expression. In the arthritic rats, both inhibitors, indomethacin and meloxicam, prevented the inhibitory effect of arthritis on body weight gain. Indomethacin and meloxicam administration to arthritic rats increased pituitary GH and liver IGF-I mRNA as well as serum levels of IGF-I. These data suggest that induction of COX-2 during chronic inflammation is involved in the inhibition of the GH-IGF-I axis and in the body weight loss. In the gastrocnemius muscle, arthritis increased the gene expression of tumor necrosis factor (TNF)-alpha, the E3 ubiquitin-ligating enzymes MAFbx and MuRF1, as well as of IGF-I and IGF-binding protein-5 (IGFBP-5). Inhibition of COX-2 by meloxicam administration increased gastrocnemius weight and decreased MAFbx, MuRF1, TNF-alpha, and IGFBP-5 gene expression. In summary, our data indicate that chronic arthritis-induced cachexia and muscle wasting are mediated by the COX-2 pathway resulting in a decreased GH-IGF-I secretion and increased expression of MAFbx and MuRF1 mRNA.

Oxidative stress, chronic disease, and muscle wasting

Underlying the pathogenesis of chronic disease is the state of oxidative stress. Oxidative stress is an imbalance in oxidant and antioxidant levels. If an overproduction of oxidants overwhelms the antioxidant defenses, oxidative damage of cells, tissues, and organs ensues. In some cases, oxidative stress is assigned a causal role in disease pathogenesis, whereas in others the link is less certain. Along with underlying oxidative stress, chronic disease is often accompanied by muscle wasting. It has been hypothesized that catabolic programs leading to muscle wasting are mediated by oxidative stress. In cases where disease is localized to the muscle, this concept is easy to appreciate. Transmission of oxidative stress from diseased remote organs to skeletal muscle is thought to be mediated by humoral factors such as inflammatory cytokines. This review examines the relationship between oxidative stress, chronic disease, and muscle wasting, and the mechanisms by which oxidative stress acts as a catabolic signal.

Effect of Celecoxib on apoptosis of human gastric cancer cell line

AIM: To explore the effect of Celecoxib (cyclooxygenase-2 inhibitor) on the apoptosis of gastric cancer cell line SGC7901 in vitro.

METHODS: After gastric cancer cell line SGC7901 was treated with Celecoxib (1×10^-5 to 1 ×10^-9 mol/L) for 24 h, the proliferration of cells was detected by MTT assay. Flow cytometry (FCM) was used to measure the apoptosis of SGC7901 cells, and immunocytochemistry was used to observe the expression of Survivin.

RESULTS: Celecoxib inhibited the proliferation of SGC7901 cells at the concentrations of 1×10^-5 to 1×10^-9 mol/L, and the maximal inhibitory rate was 30.03%, which was produced by 1×10^-5 mol/L Celecoxib. After SGC7901 cells were treated with 1×10^-5 mol/L Celecoxib for 12, 24, 48 h, the proportions of apoptosis cells were significantly increased in comparison with those of the control cells, and the apoptosis rate was 17.83% after 48 h. The expression of Survivin was decreased at 3 and 24 h, especially at 24 h.

CONCLUSION: Celecoxib can induce the apoptosis of gastric cancer cell line SGC7901 by suppressing the expression of Survivin.

Cancer cachexia: it's time for more clinical trials

Cancer cachexia (CC) is a multifactorial paraneoplastic syndrome characterized by anorexia, body weight loss, loss of adipose tissue and skeletal muscle, accounting for at least 20% of deaths in neoplastic patients. CC significantly impairs quality of life and response to anti-neoplastic therapies, increasing morbidity and mortality of cancer patients. Muscle wasting is the most important phenotypic feature of CC and the principal cause of function impairment, fatigue and respiratory complications, mainly related to a hyperactivation of muscle proteolytic pathways. Most current therapeutic strategies to counteract CC have proven to be only partially effective. In the last decade, the correction of anorexia, the inhibition of catabolic processes and the stimulation of anabolic pathways in muscle have been attempted pharmacologically with encouraging results in animal models and through preliminary clinical trials. However, data in the clinical setting are still scanty and non definitive. It is time to start prospective, randomized, controlled trials to evaluate which drugs are effective in counteracting the loss of lean of muscle mass and in improving nutritional status and quality of life in patients affected by cancer-related cachexia.

Capecitabine improves cancer cachexia and normalizes IL-6 and PTHrP levels in mouse cancer cachexia models

PURPOSE

To clarify the potential of parathyroid hormone-related protein (PTHrP) and interleukin-6 (IL-6) as cachectic factors in a colon 26 model and the effects of capecitabine on cancer cachexia as determined by plasma levels of IL-6 and PTHrP and body weight loss.

METHODS

From two colon 26 sublines-cancer cachectic clone20 and non-cachectic clone5 plasma levels of PTHrP protein and mRNA expression levels in tumor tissues were compared. An IL-6 neutralizing antibody, a PTHrP neutralizing antibody, and capecitabine were administered into mice bearing clone20 and their anticachectic effects evaluated.

RESULTS

The plasma level of PTHrP protein in mice bearing clone20 was higher than that in mice bearing clone5. The expression level of PTHrP mRNA was 49-fold higher in tumor tissues of clone20 than of clone5, according to GeneChip analysis. PTHrP antibody as well as IL-6 antibody suppressed wasting of the body and gastrocnemius and adipose tissue weights. PTHrP antibody suppressed the induction of hypercalcemia but not hypoglycemia or elevation of IL-6, whereas IL-6 antibody suppressed the induction of hypoglycemia but not hypercalcemia or elevation of PTHrP. Capecitabine, a fluorinated pyrimidine anticancer agent, improved body wasting of mice bearing clone20 at a low dose with no reduction of tumor volume. Furthermore, capecitabine lowered the levels of PTHrP and IL-6 in plasma and suppressed hypoglycemia and hypercalcemia in this model. Capecitabine also showed anticachectic effects on cachexia in a cancer model induced by human cervical cancer cell line Y (also known as Yumoto).

CONCLUSIONS

PTHrP and IL-6 were found to be factors in the development of cachexia in a colon 26 cancer model, and capecitabine improved cancer cachexia by suppressing the plasma levels of IL-6 and PTHrP in colon 26 and Y cachectic models.