Tocilizumab, a proposed therapy for the cachexia of Interleukin6-expressing lung cancer

Randomized Phase II Study of Nab-Paclitaxel and Gemcitabine With or Without Tocilizumab as First-Line Treatment in Advanced Pancreatic Cancer: Survival and Cachexia

PURPOSE

This randomized phase-II trial (ClinicalTrials.gov identifier: NCT02767557) compared efficacy of gemcitabine/nab-paclitaxel (Gem/Nab) with or without the anti-interleukin-6 (IL-6) receptor antibody tocilizumab (Toc) for advanced pancreatic cancer (PC).

METHODS

A safety cohort received Gem 1,000 mg/m2 and Nab 125 mg/m2 on days 1, 8, and 15, and Toc 8 mg/kg on day 1 for each 28-day cycle. Participants with modified Glasgow prognostic scores of 1 or 2 were randomly assigned 1:1 to receive Gem/Nab/Toc or Gem/Nab. The primary end point was the overall survival (OS) rate at 6 months (OS6). Secondary end points were progression-free survival (PFS), overall response rate (ORR), and safety. Exploratory end points were cachexia, quality of life, and biomarkers, including the cachexia-promoting protein, growth differentiation factor 15 (GDF15).

RESULTS

Overall, 147 patients were treated, including six safety cohort participants. The median follow-up period was 8.1 months (IQR, 4.2-13.9). OS6 was 68.6% (95% CI, 56.3 to 78.1) for the Gem/Nab/Toc group and 62.0% (49.6-72.1) for the Gem/Nab group (P = .409). OS for Gem/Nab/Toc versus Gem/Nab improved at 18 months (27.1% v 7.0%, P = .001). No differences in median OS, PFS, or ORR were observed. Incidence of grade-3+ treatment-related adverse events (TrAEs) was 88.1% for Gem/Nab/Toc and 63.4% for Gem/Nab (P < .001). Gem/Nab/Toc decreased muscle loss versus Gem/Nab, with median change +0.1013% versus -3.430% (P = .0012) at 2 months and +0.7044 versus -3.353% (P = .036) at 4 months. Incidence of muscle loss was 43.48% on Gem/Nab/Toc versus 73.52% on Gem/Nab at 2 months (P = .0045) and 41.82% versus 68.75% (P = .0062) at 4 months. GDF15 was not changed by Gem/Nab or Gem/Nab/Toc.

CONCLUSION

Although the primary end point was not met and TrAEs were increased by Toc, increased survival at 18 months and reduced muscle wasting support an anticachexia effect of IL-6 blockade independent of GDF15. Further studies could leverage these findings for precision anticachexia therapy.

Dynamics of Modified Cardiovascular Risk Factors in Patients with Rheumatoid Arthritis on the Background of 5-Year Therapy with an Interleukin 6 Receptor Inhibitor

The effect of an inhibitor of interleukin (IL) 6 receptors on the state of the cardiovascular system in patients with rheumatoid arthritis (RA) remains poorly understood, especially with its long-term use.

THE AIM

of this work was to study the effect of therapy with the IL-6 receptor inhibitor tocilizumab (TCZ) on the dynamics of modifiable risk factors (RF), total cardiovascular risk (CVR), structural changes in the carotid arteries (CA), and the incidence of cardiovascular complications (CVC) in patients with rheumatoid arthritis during the 260-week follow-up period.

MATERIALS AND METHODS

: The study included 37 patients with active RA (32 women and 5 men) with ineffectiveness and/or intolerance to disease modifying anti-rheumatic drugs (DMARDs); median age was 56 [48; 68] years, disease duration was 92 [49; 158] months; DAS28 (Disease Activity Score 28)-6.2 [5.5; 6.7] points; all patients were seropositive for rheumatoid factor (RF), 86%-for antibodies to cyclic citrullinated peptide (ACCP). Patients received TCZ therapy 8 mg/kg intravenously every 4 weeks; after 192 [176; 210] weeks, 60% of patients switched to subcutaneous administration of the drug at a dose of 162 mg once a week. In 51% of patients with RA, TCZ monotherapy was performed, in 49%-combination therapy of TCZ with DMARDs. Statins were received by 17 (46%) patients, including 7 patients before and 10 after inclusion in the study. All patients underwent an assessment of traditional risk factors, the total cardiovascular risk was calculated using the mSCORE scale, atherosclerotic vascular lesions were assessed by the detection of atherosclerotic plaques (ASP) of CA. The observation period was 260.4 [251.5; 283.4] weeks.

RESULTS

: After 260 weeks of TCZ therapy, RA remission was observed in 32 (86%) patients, low activity-in 5 (14%) patients. During the observation period, the frequency of modified RF and the total CVR did not change significantly, an increase in body mass index (BMI) by 11% was recorded, the number of patients with hypercholesterolemia and a reduced level of HDL cholesterol (C) decreased. In patients without statin therapy, there were no significant changes in the blood lipid spectrum. In the group of patients receiving statins, there was an increase in HDL-CH by 43%, a decrease in cholesterol levels by 15%, atherogenic index (AI) by 56% (p < 0.01 in all cases) and associations between the dynamics of ∆cholesterol and ∆CRP (r = 0.35; p = 0.04), ∆LDL-CH and ∆CRP (r = 0.41; p = 0.03). Significant structural changes in CA in RA patients by the end of  260 weeks of TCZ therapy were not identified. Initially, intima-media thickness (IMT) CA positively moderately correlated with age (r = 0.7; p < 0.01), BMI (r = 0.37; p < 0.01), systolic blood pressure (SBP) (r = 0.62; p < 0.01) and weakly with lipid spectrum parameters-cholesterol (r = 0.29; p < 0.01), LDL-CH (r = 0.36; p < 0.01). No new associations of IMT CA by the end of the observation, as well as the relationship of the IMT CA value with the indicators of RA activity and the ongoing therapy, were identified. By the end of the study, the distribution of patients by mSCORE value and CVR level did not change significantly. The incidence of CVC was 0.54 per 100 patient-years over a 260-week period of TCZ use.

CONCLUSIONS

: Against the background of long-term TCZ therapy in RA patients, there was no increase in CVR and significant structural changes in CA. It is necessary to dynamically monitor the blood lipid profile and CVR in RA patients receiving TCZ therapy. Statin therapy can successfully control dyslipidemia in RA patients who receive long-term TCZ.

Mechanisms and pharmacotherapy of cancer cachexia-associated anorexia

Cachexia is a multifactorial metabolic syndrome characterized by weight and skeletal muscle loss caused by underlying illnesses such as cancer, heart failure, and renal failure. Inflammation, insulin resistance, increased muscle protein degradation, decreased food intake, and anorexia are the primary pathophysiological drivers of cachexia. Cachexia causes physical deterioration and functional impairment, loss of quality of life, lower response to active treatment, and ultimately morbidity and mortality, while the difficulties in tackling cachexia in its advanced phases and the heterogeneity of the syndrome among patients require an individualized and multidisciplinary approach from an early stage. Specifically, strategies combining nutritional and exercise interventions as well as pharmacotherapy that directly affect the pathogenesis of cachexia, such as anti-inflammatory, metabolism-improving, and appetite-stimulating agents, have been proposed, but none of which have demonstrated sufficient evidence to date. Nevertheless, several agents have recently emerged, including anamorelin, a ghrelin receptor agonist, growth differentiation factor 15 neutralization therapy, and melanocortin receptor antagonist, as candidates for ameliorating anorexia associated with cancer cachexia. Therefore, in this review, we outline cancer cachexia-associated anorexia and its pharmacotherapy, including corticosteroids, progesterone analogs, cannabinoids, anti-psychotics, and thalidomide which have been previously explored for their efficacy, in addition to the aforementioned novel agents, along with their mechanisms.

Sarcopenia and cachexia: molecular mechanisms and therapeutic interventions

Sarcopenia is defined as a muscle-wasting syndrome that occurs with accelerated aging, while cachexia is a severe wasting syndrome associated with conditions such as cancer and immunodeficiency disorders, which cannot be fully addressed through conventional nutritional supplementation. Sarcopenia can be considered a component of cachexia, with the bidirectional interplay between adipose tissue and skeletal muscle potentially serving as a molecular mechanism for both conditions. However, the underlying mechanisms differ. Recognizing the interplay and distinctions between these disorders is essential for advancing both basic and translational research in this area, enhancing diagnostic accuracy and ultimately achieving effective therapeutic solutions for affected patients. This review discusses the muscle microenvironment's changes contributing to these conditions, recent therapeutic approaches like lifestyle modifications, small molecules, and nutritional interventions, and emerging strategies such as gene editing, stem cell therapy, and gut microbiome modulation. We also address the challenges and opportunities of multimodal interventions, aiming to provide insights into the pathogenesis and molecular mechanisms of sarcopenia and cachexia, ultimately aiding in innovative strategy development and improved treatments.

Crosstalk between lipid metabolism and EMT: emerging mechanisms and cancer therapy

Lipids are the key component of all membranes composed of a variety of molecules that transduce intracellular signaling and provide energy to the cells in the absence of nutrients. Alteration in lipid metabolism is a major factor for cancer heterogeneity and a newly identified cancer hallmark. Reprogramming of lipid metabolism affects the diverse cancer phenotypes, especially epithelial-mesenchymal transition (EMT). EMT activation is considered to be an essential step for tumor metastasis, which exhibits a crucial role in the biological processes including development, wound healing, and stem cell maintenance, and has been widely reported to contribute pathologically to cancer progression. Altered lipid metabolism triggers EMT and activates multiple EMT-associated oncogenic pathways. Although the role of lipid metabolism-induced EMT in tumorigenesis is an attractive field of research, there are still significant gaps in understanding the underlying mechanisms and the precise contributions of this interplay. Further study is needed to clarify the specific molecular mechanisms driving the crosstalk between lipid metabolism and EMT, as well as to determine the potential therapeutic implications. The increased dependency of tumor cells on lipid metabolism represents a novel therapeutic target, and targeting altered lipid metabolism holds promise as a strategy to suppress EMT and ultimately inhibit metastasis.

Cancer cachexia: multilevel metabolic dysfunction

Cancer cachexia is a complex metabolic disorder marked by unintentional body weight loss or 'wasting' of body mass, driven by multiple aetiological factors operating at various levels. It is associated with many malignancies and significantly contributes to cancer-related morbidity and mortality. With emerging recognition of cancer as a systemic disease, there is increasing awareness that understanding and treatment of cancer cachexia may represent a crucial cornerstone for improved management of cancer. Here, we describe the metabolic changes contributing to body wasting in cachexia and explain how the entangled action of both tumour-derived and host-amplified processes induces these metabolic changes. We discuss energy homeostasis and possible ways that the presence of a tumour interferes with or hijacks physiological energy conservation pathways. In that context, we highlight the role played by metabolic cross-talk mechanisms in cachexia pathogenesis. Lastly, we elaborate on the challenges and opportunities in the treatment of this devastating paraneoplastic phenomenon that arise from the complex and multifaceted metabolic cross-talk mechanisms and provide a status on current and emerging therapeutic approaches.

Tocilizumab for Advanced Non-Small-Cell Lung Cancer With Concomitant Cachexia: An Observational Study

BACKGROUND

Cancer cachexia significantly contributes to morbidity and mortality in patients with non-small-cell lung cancer (NSCLC). Inflammatory pathways mediated by interleukin-6 (IL-6) play a crucial role in the development of cancer cachexia. This study aimed to investigate the use of tocilizumab in the management of NSCLC with coexisting IL-6-elevated cachexia.

METHODS

In this retrospective study, data were collected from patients with NSCLC and concurrent IL-6-elevated cachexia who received either tocilizumab plus antitumour therapy or antitumour therapy alone. The primary endpoints were overall survival (OS) and improved modified Glasgow Prognostic Score (mGPS) at Week 12. The secondary endpoints included changes from baseline over 12 weeks in body weight, albumin, C-reactive protein (CRP) and mGPS. Qualitative improvements in patient self-rated appetite and fatigue were reported as exploratory analysis.

RESULTS

The study included 49 patients diagnosed with NSCLC and IL-6-elevated cachexia, Eastern Cooperative Oncology Group performance status of 2-4. Of these, 26 received tocilizumab in combination with antitumour therapy, and 23 received antitumour therapy alone. The majority of these patients were male (87.8%). Baseline characteristics were almost identical between the two groups. The tocilizumab group demonstrated a significantly longer median OS compared to the control group (15.1 vs. 3.2 months; hazard ratio 0.18, 95% confidence interval 0.08-0.38; p < 0.001). The rate of patients surviving with mGPS improvement at Week 12 was significantly higher in the tocilizumab group than in the control group (risk difference 0.88, 95% confidence interval 0.75-1.00; p < 0.001). Over the 12-week period, significant improvements were observed in body weight, albumin, CRP and mGPS in the tocilizumab group compared to the control group (body weight: 5.15 ± 0.53 kg vs. -5.69 ± 0.76 kg, p = 0.041; albumin: 5.89 ± 0.70 g/L vs. -2.97 ± 0.71 g/L, p < 0.001; CRP: -91.50 ± 7.15 mg/L vs. 9.47 ± 13.69 mg/L, p < 0.001; mGPS: -1.61 ± 0.15 vs. 0.03 ± 0.08, p < 0.001). The tocilizumab group also displayed significantly higher rates of improvement in appetite and fatigue (both p < 0.001). The incidence of Grade 3 or higher adverse events was 34.6% in the tocilizumab group compared to 78.3% in the control group. Tocilizumab-related adverse events were observed in three patients (11.5%), including two cases of neutropenia and one case of skin and subcutaneous tissue infection.

CONCLUSION

Tocilizumab demonstrated significant benefits in survival and various clinical parameters, including body weight, albumin, CRP, mGPS and symptom burden in patients with NSCLC and concurrent IL-6-elevated cachexia. Given the existing unmet medical need for effective interventions for cancer cachexia, tocilizumab may be considered as a potential treatment option.

Interleukin-6: Cardiovascular Aspects of Long-Term Cytokine Suppression in Patients with Rheumatoid Arthritis

In recent years, many atherogenesis researchers have focused on the role of inflammatory cytokines in the development of cardiovascular disease (CVD). Interleukin-6 (IL-6) cytokine is independently associated with higher CVD risk in patients with rheumatoid arthritis (RA). The effect of IL-6 inhibitors on the cardiovascular system in RA patients remains poorly understood, especially with its long-term use. This study investigates the effect of therapy with IL-6 receptor blocker tocilizumab (TCZ) on the dynamics of cardiovascular risk (CVR), modifiable risk factors (RFs), carotid artery (CA) structural changes, and the incidence of cardiovascular complications (CVCs) in RA patients during a 265-week follow-up period. Forty-five patients with active RA (DAS28-ESR 6.2 (5.5;6.8) with ineffectiveness and/or intolerance to disease-modifying antirheumatic drugs (DMARDs) were included in this study. During long-term therapy with TCZ in RA patients, no increase in CVR and no significant structural changes in CA were observed. No significant changes in the blood lipid spectrum were observed in patients without statin therapy. In the group of patients receiving statins, there was a 43% increase in high-density lipoprotein cholesterol (HDL-C), a 15% reduction in total cholesterol levels, and a 56% decrease in the atherogenicity index (p < 0.01 in all cases). Associations were found between ∆ total cholesterol and ∆ C-reactive protein (CRP) (R = 0.36, p = 0.04), ∆ low-density lipoprotein cholesterol (LDL-C), and ∆-CRP (R = 0.42, p = 0.03) in RA patients receiving statins. Initially, the thickness of the intima-media complex of carotid arteries (cIMT) positively moderately correlated with age (R = 0.7; p < 0.01), BMI (R = 0.37; p < 0.01), and systolic blood pressure (R = 0.64; p < 0.01); however, it weakly correlated with the lipid spectrum parameters: total cholesterol (R = 0.29; p < 0.01) and LDL-C (R = 0.33; p < 0.01). No new associations of cIMT by the end of the follow-up period, as well as the relationship of cIMT value with RA activity and therapy, were revealed. Patients with carotid ASPs showed an oppositely directed relationship between total cholesterol and sVCAM-1 at baseline (R = -0.25, p = 0.01) and at the end of this study (R = 0.29, p < 0.01). The incidence of cardiovascular events was 0.53 per 100 patient-years during the 265-week period of TCZ therapy.

A comprehensive review of animal models for cancer cachexia: Implications for translational research

Cancer cachexia is a multifactorial syndrome characterized by progressive weight loss and a disease process that nutritional support cannot reverse. Although progress has been made in preclinical research, there is still a long way to go in translating research findings into clinical practice. One of the main reasons for this is that existing preclinical models do not fully replicate the conditions seen in clinical patients. Therefore, it is important to understand the characteristics of existing preclinical models of cancer cachexia and pay close attention to the latest developments in preclinical models. The main models of cancer cachexia used in current research are allogeneic and xenograft models, genetically engineered mouse models, chemotherapy drug-induced models, Chinese medicine spleen deficiency models, zebrafish and Drosophila models, and cellular models. This review aims to revisit and summarize the commonly used animal models of cancer cachexia by evaluating existing preclinical models, to provide tools and support for translational medicine research.

The role of interleukin-6 family cytokines in cancer cachexia

Cachexia is a wasting syndrome that manifests in more than half of all cancer patients. Cancer-associated cachexia negatively influences the survival of patients and their quality of life. It is characterized by a rapid loss of adipose and skeletal muscle tissues, which is partly mediated by inflammatory cytokines. Here, we explored the crucial roles of interleukin-6 (IL-6) family cytokines, including IL-6, leukemia inhibitory factor, and oncostatin M, in the development of cancer cachexia. These cytokines have been shown to exacerbate cachexia by promoting the wasting of adipose and muscle tissues, activating mechanisms that enhance lipolysis and proteolysis. Overlapping effects of the IL-6 family cytokines depend on janus kinase/signal transducer and activator of transcription 3 signaling. We argue that the blockade of these cytokine pathways individually may fail due to redundancy and future therapeutic approaches should target common downstream elements to yield effective clinical outcomes.

Evaluation of drug resistance for EGFR-TKIs in lung cancer via multicellular lung-on-a-chip

Drug resistance to irreversible epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) is a primary factor affecting their therapeutic efficacy in human non-small cell lung cancer (NSCLC). NSCLC cells can undergo epithelial-mesenchymal transition (EMT) induced by many factors in the tumour microenvironment (TME), which plays a crucial role in tumour drug resistance. In this study, a multicellular lung-on-a-chip that can realise the cell co-culture of the human non-small cell lung cancer cell line HCC827, human foetal lung fibroblasts (HFL-1), and human umbilical vein endothelial cells (HUVECs) is prepared. The TME was simulated on the chip combined with perfusion and other factors, and the drug evaluation of osimertinib was performed to explore the drug resistance mechanism of EGFR-TKIs. In the early stages, a two-dimensional static cell co-culture was achieved by microchip, and the results showed that HFL-1 cells could be transformed into cancer-associated fibroblasts (CAFs), and HCC827 cells could undergo EMT, both of which were mediated by Interleukin-6 (IL-6). Vimentin (VIM) and Alpha Skeletal Muscle Actin (a-SMA) expression of HFL-1 was upregulated, whereas E-cadherin (E-cad) expression of HCC827 was down-regulated. Further, N-cadherin (N-cad) expression of HCC827 was upregulated. In both the static cell co-culture and multicellular lung-on-a-chip, HCC827 cells with CAFs co-culture or IL-6 treatment developed resistance to osimertinib. Further use of the IL-6 antibody inhibitor tocilizumab could reverse EGFR-TKI resistance to a certain extent. Combination therapy with tocilizumab and EGFR-TKIs may provide a novel therapeutic strategy for overcoming EGFR-TKI resistance caused by EMT in NSCLC. Furthermore, the lung-on-a-chip can simulate complex TME and can be used for evaluating tumour resistance and exploring mechanisms, with the potential to become an important tool for personalised diagnosis, treatment, and biomedical research.

Interleukin-6 serves as a critical factor in various cancer progression and therapy

Interleukin-6 (IL-6), a pro-inflammatory cytokine, plays a crucial role in host immune defense and acute stress responses. Moreover, it modulates various cellular processes, including proliferation, apoptosis, angiogenesis, and differentiation. These effects are facilitated by various signaling pathways, particularly the signal transducer and activator of transcription 3 (STAT3) and Janus kinase 2 (JAK2). However, excessive IL-6 production and dysregulated signaling are associated with various cancers, promoting tumorigenesis by influencing all cancer hallmarks, such as apoptosis, survival, proliferation, angiogenesis, invasiveness, metastasis, and notably, metabolism. Emerging evidence indicates that selective inhibition of the IL-6 signaling pathway yields therapeutic benefits across diverse malignancies, such as multiple myeloma, prostate, colorectal, renal, ovarian, and lung cancers. Targeting key components of IL-6 signaling, such as IL-6Rs, gp130, STAT3, and JAK via monoclonal antibodies (mAbs) or small molecules, is a heavily researched approach in preclinical cancer studies. The purpose of this study is to offer an overview of the role of IL-6 and its signaling pathway in various cancer types. Furthermore, we discussed current preclinical and clinical studies focusing on targeting IL-6 signaling as a therapeutic strategy for various types of cancer.

Administration of adiponectin receptor agonist AdipoRon relieves cancer cachexia by mitigating inflammation in tumour-bearing mice

BACKGROUND

Cancer cachexia is a life-threatening, inflammation-driven wasting syndrome that remains untreatable. Adiponectin, the most abundant adipokine, plays an important role in several metabolic processes as well as in inflammation modulation. Our aim was to test whether administration of AdipoRon (AR), a synthetic agonist of the adiponectin receptors, prevents the development of cancer cachexia and its related muscle atrophy.

METHODS

The effect of AR on cancer cachexia was investigated in two distinct murine models of colorectal cancer. First, 7-week-old CD2F1 male mice were subcutaneously injected with colon-26 carcinoma cells (C26) or vehicle (CT). Six days after injection, mice were treated for 5 days with AdipoRon (50 mg/kg/day; C26 + AR) or the corresponding vehicle (CT and C26). Additionally, a genetic model, the ApcMin/+ mouse, that develops spontaneously numerous intestinal polyps, was used. Eight-week-old male ApcMin/+ mice were treated with AdipoRon (50 mg/kg/day; Apc + AR) or the corresponding vehicle (Apc) over a period of 12 weeks, with C57BL/6J wild-type mice used as controls. In both models, several parameters were assessed in vivo: body weight, grip strength and serum parameters, as well as ex vivo: molecular changes in muscle, fat and liver.

RESULTS

The protective effect of AR on cachexia development was observed in both cachectic C26 and ApcMin/+ mice. In these mice, AR administration led to a significant alleviation of body weight loss and muscle wasting, together with rescued muscle strength (P < 0.05 for all). In both models, AR had a strong anti-inflammatory effect, reflected by lower systemic interleukin-6 levels (-55% vs. C26, P < 0.001 and -80% vs. Apc mice, P < 0.05), reduced muscular inflammation as indicated by lower levels of Socs3, phospho-STAT3 and Serpina3n, an acute phase reactant (P < 0.05 for all). In addition, AR blunted circulating levels of corticosterone (-46% vs. C26 mice, P < 0.001 and -60% vs. Apc mice, P < 0.05), the predominant murine glucocorticoid known to induce muscle atrophy. Accordingly, key glucocorticoid-responsive factors implicated in atrophy programmes were-or tended to be-significantly blunted in skeletal muscle by AR. Finally, AR protected against lipid metabolism alterations observed in ApcMin/+ mice, as it mitigated the increase in circulating triglyceride levels (-38%, P < 0.05) by attenuating hepatic triglyceride synthesis and fatty acid uptake by the liver.

CONCLUSIONS

Altogether, these results show that AdipoRon rescued the cachectic phenotype by alleviating body weight loss and muscle atrophy, along with restraining inflammation and hypercorticism in preclinical murine models. Therefore, AdipoRon could represent an innovative therapeutic strategy to counteract cancer cachexia.

Area postrema neurons mediate interleukin-6 function in cancer cachexia

Interleukin-6 (IL-6) has been long considered a key player in cancer cachexia. It is believed that sustained elevation of IL-6 production during cancer progression causes brain dysfunctions, which ultimately result in cachexia. However, how peripheral IL-6 influences the brain remains poorly understood. Here we show that neurons in the area postrema (AP), a circumventricular structure in the hindbrain, is a critical mediator of IL-6 function in cancer cachexia in male mice. We find that circulating IL-6 can rapidly enter the AP and activate neurons in the AP and its associated network. Peripheral tumor, known to increase circulating IL-6, leads to elevated IL-6 in the AP, and causes potentiated excitatory synaptic transmission onto AP neurons and AP network hyperactivity. Remarkably, neutralization of IL-6 in the brain of tumor-bearing mice with an anti-IL-6 antibody attenuates cachexia and the hyperactivity in the AP network, and markedly prolongs lifespan. Furthermore, suppression of Il6ra, the gene encoding IL-6 receptor, specifically in AP neurons with CRISPR/dCas9 interference achieves similar effects. Silencing Gfral-expressing AP neurons also attenuates cancer cachectic phenotypes and AP network hyperactivity. Our study identifies a central mechanism underlying the function of peripheral IL-6, which may serve as a target for treating cancer cachexia.

Causal relationship of interleukin-6 and its receptor on sarcopenia traits using mendelian randomization

BACKGROUND

Previous research has extensively examined the role of interleukin 6 (IL-6) in sarcopenia. However, the presence of a causal relationship between IL-6, its receptor (IL-6R), and sarcopenia remains unclear.

METHOD

In this study, we utilized summary-level data from genome-wide association studies (GWAS) focused on appendicular lean mass (ALM), hand grip strength, and walking pace. Single nucleotide polymorphisms (SNPs) were employed as genetic instruments for IL-6 and IL-6R to estimate the causal effect of sarcopenia traits. We adopted the Mendelian randomization (MR) approach to investigate these associations using the inverse variance weighted (IVW) method as the primary analytical approach. Additionally, we performed sensitivity analyses to validate the reliability of the MR results.

RESULT

This study revealed a significant negative association between main IL-6R and eQTL IL-6R on the left grip strength were - 0.013 (SE = 0.004, p < 0.001) and -0.029 (SE = 0.007, p < 0.001), respectively. While for the right grip strength, the estimates were - 0.011 (SE = 0.001, p < 0.001) and - 0.021 (SE = 0.008, p = 0.005). However, no evidence of an association for IL-6R with ALM and walking pace. In addition, IL-6 did not affect sarcopenia traits.

CONCLUSION

Our study findings suggest a negative association between IL-6R and hand grip strength. Additionally, targeting IL-6R may hold potential value as a therapeutic approach for the treatment of hand grip-related issues.

Musculoskeletal crosstalk in chronic obstructive pulmonary disease and comorbidities: Emerging roles and therapeutic potentials

Chronic Obstructive Pulmonary Disease (COPD) is a multifaceted respiratory disorder characterized by progressive airflow limitation and systemic implications. It has become increasingly apparent that COPD exerts its influence far beyond the respiratory system, extending its impact to various organ systems. Among these, the musculoskeletal system emerges as a central player in both the pathogenesis and management of COPD and its associated comorbidities. Muscle dysfunction and osteoporosis are prevalent musculoskeletal disorders in COPD patients, leading to a substantial decline in exercise capacity and overall health. These manifestations are influenced by systemic inflammation, oxidative stress, and hormonal imbalances, all hallmarks of COPD. Recent research has uncovered an intricate interplay between COPD and musculoskeletal comorbidities, suggesting that muscle and bone tissues may cross-communicate through the release of signalling molecules, known as "myokines" and "osteokines". We explored this dynamic relationship, with a particular focus on the role of the immune system in mediating the cross-communication between muscle and bone in COPD. Moreover, we delved into existing and emerging therapeutic strategies for managing musculoskeletal disorders in COPD. It underscores the development of personalized treatment approaches that target both the respiratory and musculoskeletal aspects of COPD, offering the promise of improved well-being and quality of life for individuals grappling with this complex condition. This comprehensive review underscores the significance of recognizing the profound impact of COPD on the musculoskeletal system and its comorbidities. By unravelling the intricate connections between these systems and exploring innovative treatment avenues, we can aspire to enhance the overall care and outcomes for COPD patients, ultimately offering hope for improved health and well-being.

Oncostatin M signaling drives cancer-associated skeletal muscle wasting

Progressive weakness and muscle loss are associated with multiple chronic conditions, including muscular dystrophy and cancer. Cancer-associated cachexia, characterized by dramatic weight loss and fatigue, leads to reduced quality of life and poor survival. Inflammatory cytokines have been implicated in muscle atrophy; however, available anticytokine therapies failed to prevent muscle wasting in cancer patients. Here, we show that oncostatin M (OSM) is a potent inducer of muscle atrophy. OSM triggers cellular atrophy in primary myotubes using the JAK/STAT3 pathway. Identification of OSM targets by RNA sequencing reveals the induction of various muscle atrophy-related genes, including Atrogin1. OSM overexpression in mice causes muscle wasting, whereas muscle-specific deletion of the OSM receptor (OSMR) and the neutralization of circulating OSM preserves muscle mass and function in tumor-bearing mice. Our results indicate that activated OSM/OSMR signaling drives muscle atrophy, and the therapeutic targeting of this pathway may be useful in preventing muscle wasting.

R-ketorolac ameliorates cancer-associated cachexia and prolongs survival of tumour-bearing mice

BACKGROUND

Cancer-associated cachexia (CAC) is a debilitating syndrome associated with poor quality of life and reduced life expectancy of cancer patients. CAC is characterized by unintended body weight reduction due to muscle and adipose tissue loss. A major hallmark of CAC is systemic inflammation. Several non-steroidal anti-inflammatory drugs (NSAIDs) have been suggested for CAC treatment, yet no single medication has proven reliable. R-ketorolac (RK) is the R-enantiomer of a commonly used NSAID. The effect of RK on CAC has not yet been evaluated.

METHODS

Ten- to 11-week-old mice were inoculated with C26 or CHX207 cancer cells or vehicle control (phosphate-buffered saline [PBS]). After cachexia onset, 2 mg/kg RK or PBS was administered daily by oral gavage. Body weight, food intake and tumour size were continuously measured. At study endpoints, blood was drawn, mice were sacrificed and tissues were excised. Immune cell abundance was analysed using a Cytek® Aurora spectral flow cytometer. Cyclooxygenase (COX) activity was determined in lung homogenates using a fluorometric kit. Muscle tissues were analysed for mRNA and protein expression by quantitative real-time PCR and western blotting analysis, respectively. Muscle fibre size was determined on histological slides after haematoxylin/eosin staining.

RESULTS

Ten-day survival rate of C26-bearing animals was 10% while RK treatment resulted in a 100% survival rate (P = 0.0009). Chemotherapy resulted in a 10% survival rate 14 days after treatment initiation, but all mice survived upon co-medication with RK and cyclophosphamide (P = 0.0001). Increased survival was associated with a protection from body weight loss in C26 (-0.61 ± 1.82 vs. -4.48 ± 2.0 g, P = 0.0004) and CHX207 (-0.49 ± 0.33 vs. -2.49 ± 0.93 g, P = 0.0003) tumour-bearing mice treated with RK, compared with untreated mice. RK ameliorated musculus quadriceps (-1.7 ± 7.1% vs. -27.8 ± 8.3%, P = 0.0007) and gonadal white adipose tissue (-18.8 ± 49% vs. -69 ± 15.6%, P = 0.094) loss in tumour-bearing mice, compared with untreated mice. Mechanistically, RK reduced circulating interleukin-6 (IL-6) concentrations from 334 ± 151 to 164 ± 123 pg/mL (P = 0.047) in C26 and from 93 ± 39 to 35 ± 6 pg/mL (P = 0.0053) in CHX207 tumour-bearing mice. Moreover, RK protected mice from cancer-induced T-lymphopenia (+1.8 ± 42% vs. -49.2 ± 12.1% in treated vs. untreated mice, respectively). RK was ineffective in ameliorating CAC in thymus-deficient nude mice, indicating that the beneficial effect of RK depends on T-cells.

CONCLUSIONS

RK improved T-lymphopenia and decreased systemic IL-6 concentrations, resulting in alleviation of cachexia and increased survival of cachexigenic tumour-bearing mice, even under chemotherapy and independent of COX inhibition. Considering its potential, we propose that the use of RK should be investigated in patients suffering from CAC.

Cancer cachexia: Focus on cachexia factors and inter-organ communication

ABSTRACT

Cancer cachexia is a multi-organ syndrome and closely related to changes in signal communication between organs, which is mediated by cancer cachexia factors. Cancer cachexia factors, being the general name of inflammatory factors, circulating proteins, metabolites, and microRNA secreted by tumor or host cells, play a role in secretory or other organs and mediate complex signal communication between organs during cancer cachexia. Cancer cachexia factors are also a potential target for the diagnosis and treatment. The pathogenesis of cachexia is unclear and no clear effective treatment is available. Thus, the treatment of cancer cachexia from the perspective of the tumor ecosystem rather than from the perspective of a single molecule and a single organ is urgently needed. From the point of signal communication between organs mediated by cancer cachexia factors, finding a deeper understanding of the pathogenesis, diagnosis, and treatment of cancer cachexia is of great significance to improve the level of diagnosis and treatment. This review begins with cancer cachexia factors released during the interaction between tumor and host cells, and provides a comprehensive summary of the pathogenesis, diagnosis, and treatment for cancer cachexia, along with a particular sight on multi-organ signal communication mediated by cancer cachexia factors. This summary aims to deepen medical community's understanding of cancer cachexia and may conduce to the discovery of new diagnostic and therapeutic targets for cancer cachexia.

Muscle wasting: emerging pathways and potential drug targets

Muscle wasting is a serious comorbidity associated with many disorders, including cancer, kidney disease, heart failure, and aging. Progressive loss of skeletal muscle mass negatively influences prognosis and survival, and is often accompanied by frailty and poor quality of life. Clinical trials testing therapeutics against muscle wasting have yielded limited success. Some therapies improved muscle mass in patients without appreciable differences in physical performance. This review article discusses emerging pathways that regulate muscle atrophy, including oncostatin M (OSM) and ectodysplasin A2 (EDA2) receptor (EDA2R) signaling, outcomes of recent clinical trials, and potential drug targets for future therapies.

Cancer-associated cachexia - understanding the tumour macroenvironment and microenvironment to improve management

Cachexia is a devastating, multifactorial and often irreversible systemic syndrome characterized by substantial weight loss (mainly of skeletal muscle and adipose tissue) that occurs in around 50-80% of patients with cancer. Although this condition mainly affects skeletal muscle (which accounts for approximately 40% of total body weight), cachexia is a multi-organ syndrome that also involves white and brown adipose tissue, and organs including the bones, brain, liver, gut and heart. Notably, cachexia accounts for up to 20% of cancer-related deaths. Cancer-associated cachexia is invariably associated with systemic inflammation, anorexia and increased energy expenditure. Understanding these mechanisms is essential, and the progress achieved in this area over the past decade could help to develop new therapeutic approaches. In this Review, we examine the currently available evidence on the roles of both the tumour macroenvironment and microenvironment in cancer-associated cachexia, and provide an overview of the novel therapeutic strategies developed to manage this syndrome.

Conditioned Media from Head and Neck Cancer Cell Lines and Serum Samples from Head and Neck Cancer Patients Drive Catabolic Pathways in Cultured Muscle Cells

BACKGROUND

The role of secreted factors from the tumor cells in driving cancer cachexia and especially muscle loss is unknown. We wanted to study both the action of secreted factors from head and neck cancer (HNC) cell lines and circulating factors in HNC patients on skeletal muscle protein catabolism.

METHODS

Conditioned media (CM) made from head and neck cancer cell lines and mix of sera from head and neck cancer (HNC) patients were incubated for 48 h with human myotubes. The atrophy and the catabolic pathway were monitored in myotubes. The patients were classified regarding their skeletal muscle loss observed at the outset of management.

RESULTS

Tumor CM (TCM) was able to produce atrophy on myotubes as compared with control CM (CCM). However, a mix of sera from HNC patients was not able to produce atrophy in myotubes. Despite this discrepancy on atrophy, we observed a similar regulation of the catabolic pathways by the tumor-conditioned media and mix of sera from cancer patients. The catabolic response after incubation with the mix of sera seemed to depend on the muscle loss seen in patients.

CONCLUSION

This study found evidence that the atrophy observed in HNC patients cannot be solely explained by a deficit in food intake.

Area postrema neurons mediate interleukin-6 function in cancer-associated cachexia

Interleukin-6 (IL-6) has been long considered a key player in cancer-associated cachexia 1-15 . It is believed that sustained elevation of IL-6 production during cancer progression causes brain dysfunctions, which ultimately result in cachexia 16-20 . However, how peripheral IL-6 influences the brain remains poorly understood. Here we show that neurons in the area postrema (AP), a circumventricular structure in the hindbrain, mediate the function of IL-6 in cancer-associated cachexia in mice. We found that circulating IL-6 can rapidly enter the AP and activate AP neurons. Peripheral tumor, known to increase circulating IL-6 1-5,15,18,21-23 , leads to elevated IL-6 and neuronal hyperactivity in the AP, and causes potentiated excitatory synaptic transmission onto AP neurons. Remarkably, neutralization of IL-6 in the brain of tumor-bearing mice with an IL-6 antibody prevents cachexia, reduces the hyperactivity in an AP network, and markedly prolongs lifespan. Furthermore, suppression of Il6ra , the gene encoding IL-6 receptor, specifically in AP neurons with CRISPR/dCas9 interference achieves similar effects. Silencing of Gfral-expressing AP neurons also ameliorates the cancer-associated cachectic phenotypes and AP network hyperactivity. Our study identifies a central mechanism underlying the function of peripheral IL-6, which may serve as a target for treating cancer-associated cachexia.

Stroma-derived miR-214 coordinates tumor dissemination

BACKGROUND

Tumor progression is based on a close interaction between cancer cells and Tumor MicroEnvironment (TME). Here, we focus on the role that Cancer Associated Fibroblasts (CAFs), Mesenchymal Stem Cells (MSCs) and microRNAs (miRs) play in breast cancer and melanoma malignancy.

METHODS

We used public databases to investigate miR-214 expression in the stroma compartment of primary human samples and evaluated tumor formation and dissemination following tumor cell injections in miR-214 overexpressing (miR-214over) and knock out (miR-214ko) mice. In addition, we dissected the impact of Conditioned Medium (CM) or Extracellular Vesicles (EVs) derived from miR-214-rich or depleted stroma cells on cell metastatic traits.

RESULTS

We evidence that the expression of miR-214 in human cancer or metastasis samples mostly correlates with stroma components and, in particular, with CAFs and MSCs. We present data revealing that the injection of tumor cells in miR-214over mice leads to increased extravasation and metastasis formation. In line, treatment of cancer cells with CM or EVs derived from miR-214-enriched stroma cells potentiate cancer cell migration/invasion in vitro. Conversely, dissemination from tumors grown in miR-214ko mice is impaired and metastatic traits significantly decreased when CM or EVs from miR-214-depleted stroma cells are used to treat cells in culture. Instead, extravasation and metastasis formation are fully re-established when miR-214ko mice are pretreated with miR-214-rich EVs of stroma origin. Mechanistically, we also show that tumor cells are able to induce miR-214 production in stroma cells, following the activation of IL-6/STAT3 signaling, which is then released via EVs subsequently up-taken by cancer cells. Here, a miR-214-dependent pro-metastatic program becomes activated.

CONCLUSIONS

Our findings highlight the relevance of stroma-derived miR-214 and its release in EVs for tumor dissemination, which paves the way for miR-214-based therapeutic interventions targeting not only tumor cells but also the TME.

Review of the endocrine organ-like tumor hypothesis of cancer cachexia in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal types of solid tumors, associated with a high prevalence of cachexia (~80%). PDAC-derived cachexia (PDAC-CC) is a systemic disease involving the complex interplay between the tumor and multiple organs. The endocrine organ-like tumor (EOLT) hypothesis may explain the systemic crosstalk underlying the deleterious homeostatic shifts that occur in PDAC-CC. Several studies have reported a markedly heterogeneous collection of cachectic mediators, signaling mechanisms, and metabolic pathways, including exocrine pancreatic insufficiency, hormonal disturbance, pro-inflammatory cytokine storm, digestive and tumor-derived factors, and PDAC progression. The complexities of PDAC-CC necessitate a careful review of recent literature summarizing cachectic mediators, corresponding metabolic functions, and the collateral impacts on wasting organs. The EOLT hypothesis suggests that metabolites, genetic instability, and epigenetic changes (microRNAs) are involved in cachexia development. Both tumors and host tissues can secrete multiple cachectic factors (beyond only inflammatory mediators). Some regulatory molecules, metabolites, and microRNAs are tissue-specific, resulting in insufficient energy production to support tumor/cachexia development. Due to these complexities, changes in a single factor can trigger bi-directional feedback circuits that exacerbate PDAC and result in the development of irreversible cachexia. We provide an integrated review based on 267 papers and 20 clinical trials from PubMed and ClinicalTrials.gov database proposed under the EOLT hypothesis that may provide a fundamental understanding of cachexia development and response to current treatments.

Inflammation as a Therapeutic Target in Cancer Cachexia

Cachexia is a common complication of cancer and is associated with poor quality of life and a decrease in survival. Many patients with cancer cachexia suffer from inflammation associated with elevated cytokines, such as interleukin-1beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor (TNF). Single-agent trials to treat cancer cachexia have not led to substantial benefit as the type of cytokine which is elevated has rarely been specified and targeted. Cachexia may also be multifactorial, involving inflammation, anorexia, catabolism, depression, and pain, and targeting the multiple causes will likely be necessary to achieve improvement in weight and appetite. A PUBMED search revealed over 3000 articles on cancer cachexia in the past ten years. We attempted to review any studies related to inflammation and cancer cachexia identified by Google Scholar and PUBMED and further search for articles listed in their references. The National Comprehensive Cancer Network (NCCN) guidelines do not provide any suggestion for managing cancer cachexia except a dietary consult. A more targeted approach to developing therapies for cancer cachexia might lead to more personalized and effective therapy.

Cancer cachexia as a multiorgan failure: Reconstruction of the crime scene

Cachexia is a devastating syndrome associated with the end-stage of several diseases, including cancer, and characterized by body weight loss and severe muscle and adipose tissue wasting. Although different cancer types are affected to diverse extents by cachexia, about 80% of all cancer patients experience this comorbidity, which highly reduces quality of life and response to therapy, and worsens prognosis, accounting for more than 25% of all cancer deaths. Cachexia represents an urgent medical need because, despite several molecular mechanisms have been identified, no effective therapy is currently available for this devastating syndrome. Most studies focus on skeletal muscle, which is indeed the main affected and clinically relevant organ, but cancer cachexia is characterized by a multiorgan failure. In this review, we focus on the current knowledge on the multiple tissues affected by cachexia and on the biomarkers with the attempt to define a chronological pathway, which might be useful for the early identification of patients who will undergo cachexia. Indeed, it is likely that the inefficiency of current therapies might be attributed, at least in part, to their administration in patients at the late stages of cachexia.

A systematic review examining the relationship between cytokines and cachexia in incurable cancer

Cancer cachexia is an unmet clinical need that affects more than 50% of patients with cancer. The systemic inflammatory response, which is mediated by a network of cytokines, has an established role in the genesis and maintenance of cancer as well as in cachexia; yet, the specific role of the cytokine milieu in cachexia requires elucidation. This systematic review aims to examine the relationship between cytokines and the cachexia syndrome in patients with incurable cancer. The databases MEDLINE, EMBASE, CINAHL, CENTRAL, PsycINFO, and Web of Science were searched for studies published between 01/01/2004 and 06/01/2020. Included studies measured cytokines and their relationship with cachexia and related symptoms/signs in adults with incurable cancer. After title screening (n = 5202), the abstracts (n = 1264) and the full-text studies (n = 322) were reviewed independently by two authors. The quality assessment of the selected papers was conducted using the modified Downs and Black checklist. Overall, 1277 patients with incurable cancer and 155 healthy controls were analysed in the 17 eligible studies. The mean age of the patients was 64 ± 15 (mean ± standard deviation). Only 34% of included participants were female. The included studies were assessed as moderate-quality to high-quality evidence (mean quality score: 7.8; range: 5-10). A total of 31 cytokines were examined in this review, of which interleukin-6 (IL-6, 14 studies) and tumour necrosis factor-α (TNF-α, 12 studies) were the most common. The definitions of cachexia and the weight-loss thresholds were highly variable across studies. Although the data could not be meta-analysed due to the high degree of methodological heterogeneity, the findings were discussed in a systematic manner. IL-6, TNF-α, and IL-8 were greater in cachectic patients compared with healthy individuals. Also, IL-6 levels were higher in cachectic participants as opposed to non-cachectic patients. Leptin, interferon-γ, IL-1β, IL-10, adiponectin, and ghrelin did not demonstrate any significant difference between groups when individuals with cancer cachexia were compared against non-cachectic patients or healthy participants. These findings suggest that a network of cytokines, commonly IL-6, TNF-α, and IL-8, are associated with the development of cachexia. Yet, this relationship is not proven to be causative and future studies should opt for longitudinal designs with consistent methodological approaches, as well as adequate techniques for analysing and reporting the results.

Amelioration of cancer cachexia with preemptive administration of tumor necrosis factor-α blocker

Cancer cachexia is syndrome accompanying weight reduction, fat loss, muscle atrophy in patients with advanced cancer. Since tumor necrosis factor-α (TNF-α) played pivotal role in cancer cachexia, we hypothesized preemptive administration of TNF-α antibody might mitigate cancer cachexia. Detailed molecular mechanisms targeting muscle atrophy, cachexic inflammation, and catabolic catastrophe were explored whether TNF-α antibody can antagonize these cachexic mechanisms. Stimulated with preliminary finding human antibody, infliximab or adalimumab, significantly inhibited TNF-α as well as their signals relevant to cachexia in mice, preemptive administration of 1.5 mg/kg adalimumab was done in C-26-induced cancer cachexia. Adalimumab significantly mitigated cancer cachexia manifested with significantly lesser weight loss, leg muscle preservation, and higher survival compared to cachexia control (p<0.05). Significant ameliorating action of muscle atrophy were accompanied significant decreases of muscle-specific UPS like atrogin-1/MuRF-1, Pax-7, PCG-1α, and Mfn-2 after adalimumab (p<0.01) and significantly attenuated lipolysis with inhibition of ATGL HSL, and MMPs. Cachexic factors including IL-6 expression, serum IL-6, gp130, IL-6R, JAK2, and STAT3 were significantly inhibited with adalimumab (p<0.01). Genes implicated in cachexic inflammation like NF-κB, c-Jun/c-Fos, and MAPKs were significantly repressed, while mTOR/AKT was significantly increased adalimumab (p<0.05). Conclusively, preemptive administration of adalimumab can be tried in high risk to cancer cachexia.

Decreased miR-497-5p Suppresses IL-6 Induced Atrophy in Muscle Cells

Interleukin-6 (IL-6) is a pro-inflammatory cytokine associated with skeletal muscle wasting in cancer cachexia. The control of gene expression by microRNAs (miRNAs) in muscle wasting involves the regulation of thousands of target transcripts. However, the miRNA-target networks associated with IL6-induced muscle atrophy remain to be characterized. Here, we show that IL-6 promotes the atrophy of C2C12 myotubes and changes the expression of 20 miRNAs (5 up-regulated and 15 down-regulated). Gene Ontology analysis of predicted miRNAs targets revealed post-transcriptional regulation of genes involved in cell differentiation, apoptosis, migration, and catabolic processes. Next, we performed a meta-analysis of miRNA-published data that identified miR-497-5p, a down-regulated miRNAs induced by IL-6, also down-regulated in other muscle-wasting conditions. We used miR-497-5p mimics and inhibitors to explore the function of miR-497-5p in C2C12 myoblasts and myotubes. We found that miR-497-5p can regulate the expression of the cell cycle genes CcnD2 and CcnE1 without affecting the rate of myoblast cellular proliferation. Notably, miR-497-5p mimics induced myotube atrophy and reduced Insr expression. Treatment with miR-497-5p inhibitors did not change the diameter of the myotubes but increased the expression of its target genes Insr and Igf1r. These genes are known to regulate skeletal muscle regeneration and hypertrophy via insulin-like growth factor pathway and were up-regulated in cachectic muscle samples. Our miRNA-regulated network analysis revealed a potential role for miR-497-5p during IL6-induced muscle cell atrophy and suggests that miR-497-5p is likely involved in a compensatory mechanism of muscle atrophy in response to IL-6.

Nutrition challenges of cancer cachexia

Cancer cachexia, or progressive weight loss, often despite adequate nutrition contributes greatly to cancer morbidity and mortality. Cachexia is metabolically distinct from starvation or protein malnutrition, although many patients with cancer and cachexia exhibit lowered appetite and food consumption. Tumors affect neural mechanisms that regulate appetite and energy expenditure, while promoting wasting of peripheral tissues via catabolism of cardiac and skeletal muscle, adipose, and bone. These multimodal actions of tumors on the host suggest a need for multimodal interventions. However, multiple recent consensus guidelines for management of cancer cachexia differ in treatment recommendations, highlighting the lack of effective, available therapies. Challenges to defining appropriate nutrition or other interventions for cancer cachexia include lack of consensus on definitions, low strength of evidence from clinical trials, and a scarcity of robust, rigorous, and mechanistic studies. However, efforts to diagnose, stage, and monitor cachexia are increasing along with clinical trial activity. Furthermore, preclinical models for cancer cachexia are growing more sophisticated, encompassing a greater number of tumor types in organ-appropriate contexts and for metastatic disease to model the clinical condition more accurately. It is expected that continued growth, investment, and coordination of research in this topic will ultimately yield robust biomarkers, clinically useful classification and staging algorithms, targetable pathways, pivotal clinical trials, and ultimately, cures. Here, we provide an overview of the clinical and scientific knowledge and its limitations around cancer cachexia.

ERK5 modulates IL-6 secretion and contributes to tumor-induced immune suppression

Tumors exhibit a variety of strategies to dampen antitumor immune responses. With an aim to identify factors that are secreted from tumor cells, we performed an unbiased mass spectrometry-based secretome analysis in lung cancer cells. Interleukin-6 (IL-6) has been identified as a prominent factor secreted by tumor cells and cancer-associated fibroblasts isolated from cancer patients. Incubation of dendritic cell (DC) cultures with tumor cell supernatants inhibited the production of IL-12p70 in DCs but not the surface expression of other activation markers which is reversed by treatment with IL-6 antibody. Defects in IL-12p70 production in the DCs inhibited the differentiation of Th1 but not Th2 and Th17 cells from naïve CD4⁺ T cells. We also demonstrate that the classical mitogen-activated protein kinase, ERK5/MAPK7, is required for IL-6 production in tumor cells. Inhibition of ERK5 activity or depletion of ERK5 prevented IL-6 production in tumor cells, which could be exploited for enhancing antitumor immune responses.

Interleukins in cancer: from biology to therapy

Interleukins and associated cytokines serve as the means of communication for innate and adaptive immune cells as well as non-immune cells and tissues. Thus, interleukins have a critical role in cancer development, progression and control. Interleukins can nurture an environment enabling and favouring cancer growth while simultaneously being essential for a productive tumour-directed immune response. These properties of interleukins can be exploited to improve immunotherapies to promote effectiveness as well as to limit side effects. This Review aims to unravel some of these complex interactions.

Therapy-Induced Tumor Cell Death: Friend or Foe of Immunotherapy?

Combinatory treatments using surgery, radiotherapy and/or chemotherapy together with immunotherapy have shown encouraging results for specific subsets of tumors, but a significant proportion of tumors remains unsusceptible. Some of these inconsistencies are thought to be the consequence of an immunosuppressive tumor microenvironment (TME) caused by therapy-induced tumor cell death (TCD). An increased understanding of the molecular mechanisms governing TCD has provided valuable insights in specific signaling cascades activated by treatment and the subsequent effects on the TME. Depending on the treatment variables of conventional chemo-, radio- and immunotherapy and the genetic composition of the tumor cells, particular cell death pathways are activated. Consequently, TCD can either have tolerogenic or immunogenic effects on the local environment and thereby affect the post-treatment anti-tumor response of immune cells. Thus, identification of these events can provide new rationales to increase the efficacy of conventional therapies combined with immunotherapies. In this review, we sought to provide an overview of the molecular mechanisms initiated by conventional therapies and the impact of treatment-induced TCD on the TME. We also provide some perspectives on how we can circumvent tolerogenic effects by adequate treatment selection and manipulation of key signaling cascades.

The Role of Tumor-Stroma Interactions in Drug Resistance Within Tumor Microenvironment

Cancer cells resistance to various therapies remains to be a key challenge nowadays. For a long time, scientists focused on tumor cells themselves for the mechanisms of acquired drug resistance. However, recent evidence showed that tumor microenvironment (TME) is essential for regulating immune escape, drug resistance, progression and metastasis of malignant cells. Reciprocal interactions between cancer cells and non-malignant cells within this milieu often reshape the TME and promote drug resistance. Therefore, advanced knowledge about these sophisticated interactions is significant for the design of effective therapeutic approaches. In this review, we highlight cancer-associated fibroblasts (CAFs), tumor-associated macrophages (TAMs), tumor-associated neutrophils (TANs), myeloid-derived suppressor cells (MDSCs), T-regulatory lymphocytes (Tregs), mesenchymal stem cells (MSCs), cancer-associated adipocytes (CAAs), and tumor endothelial cells (TECs) existing in TME, as well as their multiple cross-talk with tumor cells, which eventually endows tumor cells with therapeutic resistance.

Rapid decline in visceral adipose tissue over 1 month is associated with poor prognosis in patients with unresectable pancreatic cancer

Background

Involuntary weight loss related to cachexia is common in patients with advanced cancer, but the association between body composition changes and survival is still unclear in pancreatic cancer.

Methods

We retrospectively reviewed the clinical outcomes of 55 patients with advanced pancreatic cancer undergoing palliative therapy or best supportive care (BSC). The skeletal muscle index (SMI), visceral adipose tissue index (VATI), subcutaneous adipose tissue index (SATI), and visceral to subcutaneous adipose tissue area ratio (VSR) were calculated based on the cross‐sectional area on two sets of computed tomography images obtained at cancer diagnosis and 1 month later before treatment. The prognostic value of body composition indexes at diagnosis and the changes in those indexes over 1 month was then evaluated.

Results

In total, 45 patients (81.8%) received chemotherapy, chemoradiation, or radiation therapy, whereas the remaining patients underwent BSC. There were 27 patients (49.1%) who had low SMI at cancer diagnosis. Univariate analysis showed no significant associations between the baseline body composition indexes including SMI, VATI, SATI, and VSR and survival. Meanwhile, male sex (HR, 2.79; 95% CI, 1.16–6.71, p = 0.022) and higher decrease in VATI over 1 month (HR, 2.41; 95% CI, 1.13–5.13, p = 0.023) were identified as independent risk factors for mortality in multivariate analysis.

Conclusion

Rapid decline in VAT over 1 month is closely associated with poorer survival in unresectable advanced pancreatic cancer. A short‐term assessment of body composition changes may be a rational approach to predict prognosis in these patients.

Interleukin-6 blockade, a potential adjunct therapy for post-burn hypermetabolism

Severe burns remain a leading cause of death and disability worldwide. Despite advances in patient care, the excessive and uncontrolled hypermetabolic stress response induced by this trauma inevitably affects every organ system causing substantial morbidity and mortality. Recent evidence suggests interleukin-6 (IL-6) is a major culprit underlying post-burn hypermetabolism. Indeed, genetic deletion of IL-6 alleviates various complications associated with poor clinical outcomes including the adverse remodeling of adipose tissue, cachexia and hepatic steatosis. Thus, pharmacological blockade of IL-6 may be a more favorable treatment option to fully restore metabolic function after injury. To test this, we investigated the safety and effectiveness of blocking IL-6 for post-burn hypermetabolism using a validated anti-IL-6 monoclonal antibody (mAb) in our experimental murine model. Here, we show daily anti-IL-6 mAb administration protects against burn-induced weight loss (P < .0001) without any adverse effect on mortality. At the organ level, post-burn treatment with the IL-6 blocker suppressed the thermogenic activation of adipose tissue (P < .01) and its associated wasting (P < .05). The reduction of browning-induced lipolysis (P < .0001) indirectly decreased hepatic lipotoxicity (P < .01) which improved liver dysfunction (P < .05). Importantly, the beneficial effects of this anti-IL-6 agent extended to the skin, reflected by the decrease in excessive collagen deposition (P < .001) and genes involved in pathologic fibrosis and scarring (P < .05). Together, our results indicate that post-burn IL-6 blockade leads to significant improvements in systemic hypermetabolism by inhibiting pathological alterations in key immunometabolic organs. These findings support the therapeutic potential of anti-IL-6 interventions to improve care, quality of life, and survival in burned patients.

Exercise Reduces the Resumption of Tumor Growth and Proteolytic Pathways in the Skeletal Muscle of Mice Following Chemotherapy

Simple Summary

Doxorubicin is a chemotherapeutic agent that contributes to muscle wasting. Based on the evidence that many cancer variants are associated with cachexia and that cancer patients are usually treated with chemotherapeutic agents, it is important to determine strategies to mitigate muscle atrophy. Muscle loss is a poor prognosis during cancer treatment, and exercise has emerged as a potential strategy utilized in this context. Once an ongoing regimen of chemotherapeutic treatment is not always possible, our results demonstrated that continuity of endurance exercise is a potential strategy that can be adopted when chemotherapy needs to be interrupted, minimizing the resumption of tumor growth and avoiding muscle loss.

Abstract

The pathogenesis of muscle atrophy plays a central role in cancer cachexia, and chemotherapy contributes to this condition. Therefore, the present study aimed to evaluate the effects of endurance exercise on time-dependent muscle atrophy caused by doxorubicin. For this, C57 BL/6 mice were subcutaneously inoculated with Lewis lung carcinoma cells (LLC group). One week after the tumor establishment, a group of these animals initiated the doxorubicin chemotherapy alone (LLC + DOX group) or combined with endurance exercise (LLC + DOX + EXER group). One group of animals was euthanized after the chemotherapy cycle, whereas the remaining animals were euthanized one week after the last administration of doxorubicin. The practice of exercise combined with chemotherapy showed beneficial effects such as a decrease in tumor growth rate after chemotherapy interruption and amelioration of premature death due to doxorubicin toxicity. Moreover, the protein degradation levels in mice undergoing exercise returned to basal levels after chemotherapy; in contrast, the mice treated with doxorubicin alone experienced an increase in the mRNA expression levels of the proteolytic pathways in gastrocnemius muscle (Trim63, Fbxo32, Myostatin, FoxO). Collectively, our results suggest that endurance exercise could be utilized during and after chemotherapy for mitigating muscle atrophy promoted by doxorubicin and avoid the resumption of tumor growth.

A review of medications used to control and improve the signs and symptoms of COVID-19 patients

In December 2019, an unprecedented outbreak of pneumonia associated with a novel coronavirus disease 2019 (COVID-19) emerged in Wuhan City, Hubei province, China. The virus that caused the disease was officially named by the World Health Organization (WHO) as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). According to the high transmission rate of SARS-CoV-2, it became a global pandemic and public health emergency within few months. Since SARS-CoV-2 is genetically 80% homologous with the SARS-CoVs family, it is hypothesized that medications developed for the treatment of SARS-CoVs may be useful in the control and management of SARS-CoV-2. In this regard, some medication being tested in clinical trials and in vitro studies include anti-viral RNA polymerase inhibitors, HIV-protease inhibitors, anti-inflammatory agents, angiotensin converting enzyme type 2 (ACE 2) blockers, and some other novel medications. In this communication, we reviewed the general characteristics of medications, medical usage, mechanism of action, as well as SARS-CoV-2 related trials.

Cachexia, a Systemic Disease beyond Muscle Atrophy

Cachexia is a complication of dismal prognosis, which often represents the last step of several chronic diseases. For this reason, the comprehension of the molecular drivers of such a condition is crucial for the development of management approaches. Importantly, cachexia is a syndrome affecting various organs, which often results in systemic complications. To date, the majority of the research on cachexia has been focused on skeletal muscle, muscle atrophy being a pivotal cause of weight loss and the major feature associated with the steep reduction in quality of life. Nevertheless, defining the impact of cachexia on other organs is essential to properly comprehend the complexity of such a condition and potentially develop novel therapeutic approaches.

Exploiting common aspects of obesity and cancer cachexia for future therapeutic strategies

Obesity and cancer cachexia are diseases at opposite ends of the BMI. However, despite the apparent dichotomy, these pathologies share some common underlying mechanisms that lead to profound metabolic perturbations. Insulin resistance, adipose tissue lipolysis, skeletal muscle atrophy and systemic inflammation are key players in both diseases. Several strategies for pharmacological treatments have been employed in obesity and cancer cachexia but demonstrated only limited effects. Therefore, there is still a need to develop novel, more effective strategies. In this review we summarize existing therapies and discuss potential novel strategies that could arise by bridging common aspects between obesity and cachexia. We discuss the potential role of macrophage manipulation and the modulation of inflammation by targeting Nuclear Receptors (NRs) as potential novel therapeutic strategies.

Cancer Cachexia: Definition, Staging, and Emerging Treatments

Cachexia is a multifactorial disease characterized by weight loss via skeletal muscle and adipose tissue loss, an imbalance in metabolic regulation, and reduced food intake. It is caused by factors of catabolism produced by tumors in the systemic circulation as well as physiological factors such as the imbalanced inflammatory activation, proteolysis, autophagy, and lipolysis that may occur with gastric, pancreatic, esophageal, lung cancer, liver, and bowel cancer. Cancer cachexia not only negatively affects the quality of life of patients with cancer but also reduces the effectiveness of anti-cancer chemotherapy and increases its toxicity, leading to increased cancer-related mortality and expenditure of medical resources. Currently, there are no effective medical interventions to completely reverse cachexia and no approved drugs. Adequate nutritional support is the main method of cachexia treatment, while drugs that target the inhibition of catabolism, cell damage, and excessive activation of inflammation are under study. This article reviews recent advances in the diagnosis, staging, and evaluation of cancer cachexia.

Cancer cachexia has many symptoms but only one cause: anoxia

During nearly 100 years of research on cancer cachexia (CC), science has been reciting the same mantra: it is a multifactorial syndrome. The aim of this paper is to show that the symptoms are many, but they have a single cause: anoxia. CC is a complex and devastating condition that affects a high proportion of advanced cancer patients. Unfortunately, it cannot be reversed by traditional nutritional support and it generally reduces survival time. It is characterized by significant weight loss, mainly from fat deposits and skeletal muscles. The occurrence of cachexia in cancer patients is usually a late phenomenon. The conundrum is why do similar patients with similar tumors, develop cachexia and others do not? Even if cachexia is mainly a metabolic dysfunction, there are other issues involved such as the activation of inflammatory responses and crosstalk between different cell types.  The exact mechanism leading to a wasting syndrome is not known, however there are some factors that are surely involved, such as anorexia with lower calorie intake, increased glycolytic flux, gluconeogenesis, increased lipolysis and severe tumor hypoxia. Based on this incomplete knowledge we put together a scheme explaining the molecular mechanisms behind cancer cachexia, and surprisingly, there is one cause that explains all of its characteristics: anoxia.  With this different view of CC we propose a treatment based on the physiopathology that leads from anoxia to the symptoms of CC.  The fundamentals of this hypothesis are based on the idea that CC is the result of anoxia causing intracellular lactic acidosis. This is a dangerous situation for cell survival which can be solved by activating energy consuming gluconeogenesis. The process is conducted by the hypoxia inducible factor-1α. This hypothesis was built by putting together pieces of evidence produced by authors working on related topics.

Cancer-Associated Cachexia: A Systemic Consequence of Cancer Progression

Cancer is a life-threatening disease that has plagued humans for centuries. The vast majority of cancer-related mortality results from metastasis. Indeed, the invasive growth of metastatic cancer cells in vital organs causes fatal organ dysfunction, but metastasis-related deaths also result from cachexia, a debilitating wasting syndrome characterized by an involuntary loss of skeletal muscle mass and function. In fact, about 80% of metastatic cancer patients suffer from cachexia, which often renders them too weak to tolerate standard doses of anticancer therapies and makes them susceptible to death from cardiac and respiratory failure. The goals of this review are to highlight important findings that help explain how cancer-induced systemic changes drive the development of cachexia and to discuss unmet challenges and potential therapeutic strategies targeting cachexia to improve the quality of life and survival of cancer patients.

Promising models for cancer-induced cachexia drug discovery

Introduction: Cachexia is a frequent, multifactorial syndrome associated with cancer afflicting patients' quality of life, their ability to tolerate anti-neoplastic therapies and the therapies efficacy, as well as survival. Currently, there are no approved cancer cachexia treatments other than those for the treatment of the underlying cancer. Cancer cachexia (CC) is poorly understood and hence makes clinical trial design difficult at best. This underlines the importance of well-characterized animal models to further elucidate the pathophysiology of CC and drug discovery/development.Areas covered: This review gives an overview of the available animal models and their value and limitations in translational studies.Expert opinion: Using more than one CC model to test research questions or novel compounds/treatment strategies is strongly advisable. The main reason is that models have unique signaling modalities driving cachexia that may only relate to subgroups of cancer patients. Human xenograph CC models require the use of mice with a compromised immune system, limiting their value for translational experiments. It may prove beneficial to include standard care chemotherapy in the experimental design, as many chemotherapeutic agents can induce cachexia themselves and alter the metabolic and signaling derangements of CC and thus the response to new therapeutic strategies.

Exercise as an anti-inflammatory therapy for cancer cachexia: a focus on interleukin-6 regulation

Cancer cachexia is a complicated disorder of extreme, progressive skeletal muscle wasting. It is directed by metabolic alterations and systemic inflammation dysregulation. Numerous studies have demonstrated that increased systemic inflammation promotes this type of cachexia and have suggested that cytokines are implicated in the skeletal muscle loss. Exercise is firmly established as an anti-inflammatory therapy that can attenuate or even reverse the process of muscle wasting in cancer cachexia. The interleukin IL-6 is generally considered to be a key player in the development of the microenvironment of malignancy; it promotes tumor growth and metastasis by acting as a bridge between chronic inflammation and cancerous tissue and it also induces skeletal muscle atrophy and protein breakdown. Paradoxically, a beneficial role for IL-6 has also been identified recently, and that is its status as a “founding member” of the myokine class of proteins. Skeletal muscle is an important source of circulating IL-6 in people who participate in exercise training. IL-6 acts as an anti-inflammatory myokine by inhibiting TNFα and improving glucose uptake through the stimulation of AMPK signaling. This review discusses the action of IL-6 in skeletal muscle tissue dysfunction and the role of IL-6 as an “exercise factor” that modulates the immune system. This review also sheds light on the main considerations related to the treatment of muscle wasting in cancer cachexia.

Muscle-Bone Crosstalk in the Masticatory System: From Biomechanical to Molecular Interactions

The masticatory system is a complex and highly organized group of structures, including craniofacial bones (maxillae and mandible), muscles, teeth, joints, and neurovascular elements. While the musculoskeletal structures of the head and neck are known to have a different embryonic origin, morphology, biomechanical demands, and biochemical characteristics than the trunk and limbs, their particular molecular basis and cell biology have been much less explored. In the last decade, the concept of muscle-bone crosstalk has emerged, comprising both the loads generated during muscle contraction and a biochemical component through soluble molecules. Bone cells embedded in the mineralized tissue respond to the biomechanical input by releasing molecular factors that impact the homeostasis of the attaching skeletal muscle. In the same way, muscle-derived factors act as soluble signals that modulate the remodeling process of the underlying bones. This concept of muscle-bone crosstalk at a molecular level is particularly interesting in the mandible, due to its tight anatomical relationship with one of the biggest and strongest masticatory muscles, the masseter. However, despite the close physical and physiological interaction of both tissues for proper functioning, this topic has been poorly addressed. Here we present one of the most detailed reviews of the literature to date regarding the biomechanical and biochemical interaction between muscles and bones of the masticatory system, both during development and in physiological or pathological remodeling processes. Evidence related to how masticatory function shapes the craniofacial bones is discussed, and a proposal presented that the masticatory muscles and craniofacial bones serve as secretory tissues. We furthermore discuss our current findings of myokines-release from masseter muscle in physiological conditions, during functional adaptation or pathology, and their putative role as bone-modulators in the craniofacial system. Finally, we address the physiological implications of the crosstalk between muscles and bones in the masticatory system, analyzing pathologies or clinical procedures in which the alteration of one of them affects the homeostasis of the other. Unveiling the mechanisms of muscle-bone crosstalk in the masticatory system opens broad possibilities for understanding and treating temporomandibular disorders, which severely impair the quality of life, with a high cost for diagnosis and management.

Effects of conditioned media from murine lung cancer cells and human tumor cells on cultured myotubes

Factors secreted from tumors/tumor cells are hypothesized to cause skeletal muscle wasting in cancer patients. We examined whether cancer cells secrete factors to promote atrophy by evaluating the effects of conditioned media (CM) from murine lung cancer cells and primary cultures of human lung tumor cells on cultured myotubes. We evaluated murine Lewis lung carcinoma (LLC) and KRAS^G12D cells, and primary cell lines derived from tumor biopsies from patients with lung cancer (hTCM; n = 6). In all experiments, serum content was matched across treatment groups. We hypothesized that CM from murine and human tumor cells would reduce myotube myosin content, decrease mitochondrial content, and increase mitochondrial reactive oxygen species (ROS) production. Treatment of myotubes differentiated for 7 days with CM from LLC and KRAS^G12D cells did not alter any of these variables. Effects of murine tumor cell CM were observed when myotubes differentiated for 4 days were treated with tumor cell CM and compared with undiluted differentiation media. However, these effects were not apparent if tumor cell CM treatments were compared with control cell CM or dilution controls. Finally, CM from human lung tumor primary cell lines did not modify myosin content or mitochondrial content or ROS production compared with either undiluted differentiated media, control cell CM, or dilution controls. Our results do not support the hypothesis that factors released from cultured lung cancer/tumor cells promote myotube wasting or mitochondrial abnormalities, but we cannot dismiss the possibility that these cells could secrete such factors in vivo within the native tumor microenvironment.