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Background: Cancer cachexia is a severe metabolic disorder characterized by progressive weight loss along with a dramatic loss in skeletal muscle and adipose tissue. Like cancer, cachexia progresses in stages starting with pre-cachexia to cachexia and finally to refractory cachexia. In the refractory stage, patients are no longer responsive to therapy and management of weight loss is no longer possible. It is therefore critical to detect cachexia as early as possible. In this study we applied a metabolomics approach to search for early biomarkers of cachexia.Methods: Multi-platform metabolomics analyses were applied to the murine Colon-26 (C26) model of cachexia. Tumor bearing mice (n = 5) were sacrificed every other day over the 14-day time course and control mice (n = 5) were sacrificed every fourth day starting at day 2. Linear regression modeling of the data yielded metabolic trajectories that were compared with the trajectories of body weight and skeletal muscle loss to look for early biomarkers of cachexia.Results: Weight loss in the tumor-bearing mice became significant at day 9 as did the loss of tibialis muscle. The loss of muscle in the gastrocnemius and quadriceps was significant at day 7. Reductions in amino acids were among the earliest metabolic biomarkers of cachexia. The earliest change was in methionine at day 4. Significant alterations in acylcarnitines and lipoproteins were also detected several days prior to weight loss.Conclusion: The results of this study demonstrate that metabolic alterations appear well in advance of observable weight loss. The earliest and most significant alterations were found in amino acids and lipoproteins. Validation of these results in other models of cachexia and in clinical studies will pave the way for a clinical diagnostic panel for the early detection of cachexia. Such a panel would provide a tremendous advance in cachectic patient management and in the design of clinical trials for new therapeutic interventions.

Abstract Background Pancreatic ductal adenocarcinoma (PDAC) is a particularly lethal malignancy partly due to frequent, severe cachexia. Serum activin correlates with cachexia and mortality, while exogenous activin causes cachexia in mice. Methods Isoform‐specific activin expression and activities were queried in human and murine tumours and PDAC models. Activin inhibition was by administration of soluble activin type IIB receptor (ACVR2B/Fc) and by use of skeletal muscle specific dominant negative ACVR2B expressing transgenic mice. Feed‐forward activin expression and muscle wasting activity were tested in vivo and in vitro on myotubes. Results Murine PDAC tumour‐derived cell lines expressed activin‐βA but not activin‐βB. Cachexia severity increased with activin expression. Orthotopic PDAC tumours expressed activins, induced activin expression by distant organs, and produced elevated serum activins. Soluble factors from PDAC elicited activin because conditioned medium from PDAC cells induced activin expression, activation of p38 MAP kinase, and atrophy of myotubes. The activin trap ACVR2B/Fc reduced tumour growth, prevented weight loss and muscle wasting, and prolonged survival in mice with orthotopic tumours made from activin‐low cell lines. ACVR2B/Fc also reduced cachexia in mice with activin‐high tumours. Activin inhibition did not affect activin expression in organs. Hypermuscular mice expressing dominant negative ACVR2B in muscle were protected for weight loss but not mortality when implanted with orthotopic tumours. Human tumours displayed staining for activin, and expression of the gene encoding activin‐βA (INHBA) correlated with mortality in patients with PDAC, while INHBB and other related factors did not. Conclusions Pancreatic adenocarcinoma tumours are a source of activin and elicit a systemic activin response in hosts. Human tumours express activins and related factors, while mortality correlates with tumour activin A expression. PDAC tumours also choreograph a systemic activin response that induces organ‐specific and gene‐specific expression of activin isoforms and muscle wasting. Systemic blockade of activin signalling could preserve muscle and prolong survival, while skeletal muscle‐specific activin blockade was only protective for weight loss. Our findings suggest the potential and need for gene‐specific and organ‐specific interventions. Finally, development of more effective cancer cachexia therapy might require identifying agents that effectively and/or selectively inhibit autocrine vs. paracrine activin signalling.

Abstract Background Cancer cachexia is a metabolic disorder involving perturbed energy balance and altered mitochondrial function. Chemotherapy is a primary treatment option for many types of cancer, but there is substantial evidence that some chemotherapeutic agents can also lead to the development and progression of cachexia. In this study, we apply a comprehensive and systems level metabolomics approach to characterize the metabolic perturbations in murine models of cancer‐induced and chemotherapy‐induced cachexia. Knowledge of the unique pathways through which cancer and chemotherapy drive cachexia is necessary in order to develop effective treatments. Methods The murine Colon26 (C26) adenocarcinoma xenograft model was used to study the metabolic derangements associated with cancer‐induced cachexia. In vivo administration of Folfiri (5‐fluorouracil, irinotecan, and leucovorin) was used to model chemotherapy‐induced cachexia. Comprehensive metabolic profiling was carried out using both nuclear magnetic resonance‐based and mass spectrometry‐based platforms. Analyses included plasma, muscle, and liver tissue to provide a systems level profiling. Results The study involved four groups of CD2F1 male mice (n = 4–5), including vehicle treated (V), C26 tumour hosts (CC), Folfiri treated (F), and C26 tumour hosts treated with Folfiri (CCF). Significant weight loss including skeletal muscle was observed for each of the experimental groups with the tumour hosts showing the most dramatic change (−3.74 g vs. initial body weight in the CC group). Skeletal muscle loss was evident in all experimental groups compared with V, with the CCF combination resulting in the most severe depletion of quadriceps mass (−38% vs. V; P

Abstract Background Cachexia frequently occurs in women with advanced ovarian cancer (OC), along with enhanced inflammation. Despite being responsible for one third of all cancer deaths, cachexia is generally under‐studied in OC due to a limited number of pre‐clinical animal models. We aimed to address this gap by characterizing the cachectic phenotype in a mouse model of OC. Methods Nod SCID gamma mice (n = 6–10) were injected intraperitoneally with 1 × 107 ES‐2 human OC cells to mimic disseminated abdominal disease. Muscle size and strength, as well as bone morphometry, were assessed. Tumour‐derived effects on muscle fibres were investigated in C2C12 myotube cultures. IL‐6 levels were detected in serum and ascites from tumour hosts, as well as in tumour sections. Results In about 2 weeks, ES‐2 cells developed abdominal tumours infiltrating omentum, mesentery, and adjacent organs. The ES‐2 tumours caused severe cachexia with marked loss of body weight (–12%, P < 0.01) and ascites accumulation in the peritoneal cavity (4.7 ± 1.5 mL). Skeletal muscles appeared markedly smaller in the tumour‐bearing mice (approximately –35%, P < 0.001). Muscle loss was accompanied by fibre atrophy, consistent with reduced muscle cross‐sectional area (–34%, P < 0.01) and muscle weakness (–50%, P < 0.001). Body composition assessment by dual‐energy X‐ray absorptiometry revealed decreased bone mineral density (–8%, P < 0.01) and bone mineral content (–19%, P < 0.01), also consistent with reduced trabecular bone in both femurs and vertebrae, as suggested by micro‐CT imaging of bone morphometry. In the ES‐2 mouse model, cachexia was also associated with high tumour‐derived IL‐6 levels in plasma and ascites (26.3 and 279.6 pg/mL, respectively) and with elevated phospho‐STAT3 (+274%, P < 0.001), reduced phospho‐AKT (–44%, P < 0.001) and decreased mitochondrial proteins, as well as with increased protein ubiquitination (+42%, P < 0.001) and expression of ubiquitin ligases in the skeletal muscle of tumour hosts. Similarly, ES‐2 conditioned medium directly induced fibre atrophy in C2C12 mouse myotubes (–16%, P < 0.001), consistent with elevated phospho‐STAT3 (+1.4‐fold, P < 0.001) and altered mitochondrial homoeostasis and metabolism, while inhibition of the IL‐6/STAT3 signalling by means of INCB018424 was sufficient to restore the myotubes size. Conclusions Our results suggest that the development of ES‐2 OC promotes muscle atrophy in both in vivo and in vitro conditions, accompanied by loss of bone mass, enhanced muscle protein catabolism, abnormal mitochondrial homoeostasis, and elevated IL‐6 levels. Therefore, this represents an appropriate model for the study of OC cachexia. Our model will aid in identifying molecular mediators that could be effectively targeted in order to improve muscle wasting associated with OC.

Abstract Background By the traditional definition of unintended weight loss, cachexia develops in ~80% of patients with pancreatic ductal adenocarcinoma (PDAC). Here, we measure the longitudinal body composition changes in patients with advanced PDAC undergoing 5‐fluorouracil, leucovorin, irinotecan, and oxaliplatin therapy. Methods We performed a retrospective review of 53 patients with advanced PDAC on 5‐fluorouracil, leucovorin, irinotecan, and oxaliplatin as first line therapy at Indiana University Hospital from July 2010 to August 2015. Demographic, clinical, and survival data were collected. Body composition measurement by computed tomography (CT), trend, univariate, and multivariate analysis were performed. Results Among all patients, three cachexia phenotypes were identified. The majority of patients, 64%, had Muscle and Fat Wasting (MFW), while 17% had Fat‐Only Wasting (FW) and 19% had No Wasting (NW). NW had significantly improved overall median survival (OMS) of 22.6 months vs. 13.0 months for FW and 12.2 months for MFW (P = 0.02). FW (HR = 5.2; 95% confidence interval = 1.5–17.3) and MFW (HR = 1.8; 95% confidence interval = 1.1–2.9) were associated with an increased risk of mortality compared with NW. OMS and risk of mortality did not differ between FW and MFW. Progression of disease, sarcopenic obesity at diagnosis, and primary tail tumours were also associated with decreased OMS. On multivariate analysis, cachexia phenotype and chemotherapy response were independently associated with survival. Notably, CT‐based body composition analysis detected tissue loss of >5% in 81% of patients, while the traditional definition of >5% body weight loss identified 56.6%. Conclusions Distinct cachexia phenotypes were observed in this homogeneous population of patients with equivalent stage, diagnosis, and first‐line treatment. This suggests cellular, molecular, or genetic heterogeneity of host or tumour. Survival among patients with FW was as poor as for MFW, indicating adipose tissue plays a crucial role in cachexia and PDAC mortality. Adipose tissue should be studied for its mechanistic contributions to cachexia.

A compounding feature of greater than 50% of all cancers is the high incidence of the cachexia syndrome, a complex metabolic disorder characterized by extreme weight loss due mainly to the gross depletion of skeletal muscle tissue. Although studies into the cause of cancer cachexia has spanned over multiple decades, little is known about the effects of various cancer treatments themselves on cachexia. For example, chemotherapy agents induce side effects such as nausea and anorexia, but these symptoms do not fully account for the changes seen with cancer cachexia. In this study we examine the effects of chemotherapeutic compounds, specifically, cisplatin in the colon-26 adenocarcinoma model of cancer cachexia. We find that although cisplatin is able to reduce tumor burden as expected, muscle wasting in mice nevertheless persists. Strikingly, cisplatin alone was seen to regulate muscle atrophy, which was independent of the commonly implicated ubiquitin proteasome system. Finally, we show that cisplatin is able to induce NF-κB activity in both mouse muscles and myotube cultures, suggesting that an additional side effect of cancer treatment is the regulation of muscle wasting that may be mediated through activation of the NF-κB signaling pathway.