RESUMO
Background: Cachexia is a paraneoplastic syndrome that accompanies and compromises cancer treatment, especially in advanced stages, affecting the metabolism and function of several organs. The adipose tissue is the first to respond to the presence of the tumor, contributing to the secretion of factors which drive the systemic inflammation, a hallmark of the syndrome. While inflammation is a defensive innate response, the control mechanisms have been reported to be disrupted in cachexia. On the other hand, little is known about the role of NLRP3 inflammasome in this scenario, a multiprotein complex involved in caspase-1 activation and the processing of the cytokines IL-1ß and IL-18. Aim: based on the evidence from our previous study with a rodent model of cachexia, we examined the activation of the NLRP3 inflammasome pathway in two adipose tissue depots obtained from patients with colorectal cancer and compared with that another inflammatory pathway, NF-κB. Results: For CC we found opposite modulation in ScAT and PtAT for the gene expression of TLR4, Caspase-1 (cachectic group) and for NF-κB p50, NF-κB p65, IL-1ß. CD36, expression was decreased in both depots while that of NLRP3 and IL-18 was higher in both tissues, as compared with controls and weight stable patients (WSC). Caspase-1 basal protein levels in the ScAT culture supernatant were higher in WSC and (weight stable patients) CC, when compared to controls. Basal ScAT explant culture medium IL-1ß and IL-18 protein content in ScAT supernatant was decreased in the WSC and CC as compared to CTL explants. Conclusions: The results demonstrate heterogeneous responses in the activation of genes of the NLRP3 inflammasome pathway in the adipose tissue of patients with cancer cachexia, rendering this pathway a potential target for therapy aiming at decreasing chronic inflammation in cancer.
Assuntos
Caquexia/metabolismo , Neoplasias Colorretais/complicações , Inflamassomos/metabolismo , Gordura Intra-Abdominal/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Gordura Subcutânea/metabolismo , Adulto , Idoso , Caquexia/etiologia , Caquexia/genética , Caquexia/patologia , Caspase 1/genética , Caspase 1/metabolismo , Feminino , Humanos , Inflamassomos/genética , Interleucina-18/genética , Interleucina-18/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Gordura Intra-Abdominal/patologia , Masculino , Pessoa de Meia-Idade , NF-kappa B/genética , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Transdução de Sinais , Gordura Subcutânea/patologia , Técnicas de Cultura de Tecidos , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismoRESUMO
BACKGROUND: Cachexia is a multifactorial and multiorgan syndrome associated with cancer and other chronic diseases and characterized by severe involuntary body weight loss, disrupted metabolism, inflammation, anorexia, fatigue, and diminished quality of life. This syndrome affects around 50% of patients with colon cancer and is directly responsible for the death of at least 20% of all cancer patients. Systemic inflammation has been recently proposed to underline most of cachexia-related symptoms. Nevertheless, the exact mechanisms leading to the initiation of systemic inflammation have not yet been unveiled, as patients bearing the same tumour and disease stage may or may not present cachexia. We hypothesize a role for gut barrier disruption, which may elicit persistent immune activation in the host. To address this hypothesis, we analysed the healthy colon tissue, adjacent to the tumour. METHODS: Blood and rectosigmoid colon samples (20 cm distal to tumour margin) obtained during surgery, from cachectic (CC = 25) or weight stable (WSC = 20) colon cancer patients, who signed the informed consent form, were submitted to morphological (light microscopy), immunological (immunohistochemistry and flow cytometry), and molecular (quantification of inflammatory factors by Luminex® xMAP) analyses. RESULTS: There was no statistical difference in gender and age between groups. The content of plasma interleukin 6 (IL-6) and IL-8 was augmented in cachectic patients relative to those with stable weight (P = 0.047 and P = 0.009, respectively). The number of lymphocytic aggregates/field in the gut mucosa was higher in CC than in WSC (P = 0.019), in addition to those of the lamina propria (LP) eosinophils (P < 0.001) and fibroblasts (P < 0.001). The area occupied by goblet cells in the colon mucosa was decreased in CC (P = 0.016). The M1M2 macrophages percentage was increased in the colon of CC, in relation to WSC (P = 0.042). Protein expression of IL-7, IL-13, and transforming growth factor beta 3 in the colon was significantly increased in CC, compared with WSC (P = 0.02, P = 0.048, and P = 0.048, respectively), and a trend towards a higher content of granulocyte-colony stimulating factor in CC was also observed (P = 0.061). The results suggest an increased recruitment of immune cells to the colonic mucosa in CC, as compared with WSC, in a fashion that resembles repair response following injury, with higher tissue content of IL-13 and transforming growth factor beta 3. CONCLUSIONS: The changes in the intestinal mucosa cellularity, along with modified cytokine expression in cachexia, indicate that gut barrier alterations are associated with the syndrome.
Assuntos
Caquexia/etiologia , Caquexia/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Neoplasias/complicações , Idoso , Biomarcadores , Caquexia/metabolismo , Citocinas/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Inflamação , Mediadores da Inflamação , Masculino , Pessoa de Meia-Idade , Neoplasias/metabolismo , Proteoma , ProteômicaRESUMO
BACKGROUND: Cancer cachexia is a multifactorial metabolic syndrome characterized by marked loss of adipose tissue and skeletal muscle. Fat loss from adipose tissue in cancer cachexia is partly the result of increased lipolysis. Despite the growing amount of studies focused on elucidating the mechanisms through which lipolysis-related proteins regulate the lipolytic process, there are scarce data concerning that profile in the adipose tissue of cancer cachectic patients. Considering its fundamental importance, it was our main purpose to characterize the expression of the lipolysis-related proteins in the white adipose tissue of cachectic cancer patients. METHODS: Patients from the University Hospital were divided into three groups: control, cancer cachexia (CC), and weight-stable cancer patients (WSC). To gain greater insight into adipose tissue wasting during cancer cachexia progression, we have also analyzed an experimental model of cachexia (Walker 256 carcinosarcoma). Animals were divided into: control, intermediate cachexia (IC) and terminal cachexia (TC). Subcutaneous white adipose tissue of patients and epidydimal white adipose tissue of animals were investigated regarding molecular aspects by determining the protein content and gene expression of hormone-sensitive lipase (HSL), adipose triglyceride lipase (ATGL), comparative gene identification-58 (CGI-58), perilipin 1, leptin, adiponectin, visfatin, and tumour necrosis factor alpha (TNF-alpha). RESULTS: We found augmented lipolysis in CC associated with increased HSL expression, as well as upregulation of ATGL expression and reduction in perilipin 1 content. In IC, there was an imbalance in the secretion of pro- and anti-inflammatory factors. The alterations at the end-stage of cachexia were even more profound, and there was a reduction in the expression of almost all proteins analyzed in the animals. CONCLUSIONS: Our findings show that cachexia induces important morphological, molecular, and humoral alterations in the white adipose tissue, which are specific to the stage of the syndrome.
Assuntos
Tecido Adiposo Branco/metabolismo , Caquexia/metabolismo , Lipase/metabolismo , Neoplasias/metabolismo , Gordura Subcutânea/metabolismo , Adipocinas/metabolismo , Animais , Western Blotting , Peso Corporal/fisiologia , Ingestão de Alimentos/fisiologia , Gotículas Lipídicas , Masculino , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Cachexia is a complex metabolic syndrome that promotes great weight loss, with marked muscle mass wasting. In the last years, many efforts have been directed to improve the understanding of the mechanisms involved in the disease. This syndrome is present in up to 80% of cancer patients and, despite its clinical relevance, is underdiagnosed. The orchestration of the molecular and biochemical disruptions observed in cachexia is paralleled by inflammation and the communication among the different body compartments, including the tumor and the skeletal muscle, is still not completely described. One of the mechanisms that may be involved in the transduction of the inflammatory signals and the activation of catabolic status in muscle is the participation of exosomes containing microRNAs (miRNAs) and muscle-specific miRNAs (myomiRs). Exosomes are nanovesicles, measuring from 30 to 100 µm, and able to carry miRNAs in the circulation, promoting cell-cell and tissue-tissue communication in an autocrine, paracrine, and endocrine manner. miRNAs transported in exosomes are preserved from degradation, while these nanoparticles deliver the cargo to specific cell targets, making communication more efficient. Several miRNAs are known to modulate inflammatory pathways, to induce metastasis, to mediate cancer aggressiveness and even to participate in the regulation of protein synthesis and degradation pathways in the skeletal muscle. The aim of this mini-review is to describe the present knowledge about the role of exosomal miRNAs and myomiRs in the induction of muscle mass wasting in cancer cachexia state and to explain which transcription factors, proteins, and pathways are regulated by these molecules.
RESUMO
Cachexia affects about 80% of gastrointestinal cancer patients. This multifactorial syndrome resulting in involuntary and continuous weight loss is accompanied by systemic inflammation and immune cell infiltration in various tissues. Understanding the interactions among tumor, immune cells, and peripheral tissues could help attenuating systemic inflammation. Therefore, we investigated inflammation in the subcutaneous adipose tissue and in the tumor, in weight stable and cachectic cancer patients with same diagnosis, in order to establish correlations between tumor microenvironment and secretory pattern with adipose tissue and systemic inflammation. Infiltrating monocyte phenotypes of subcutaneous and tumor vascular-stromal fraction were identified by flow cytometry. Gene and protein expression of inflammatory and chemotactic factors was measured with qRT-PCR and Multiplex Magpix(®) system, respectively. Subcutaneous vascular-stromal fraction exhibited no differences in regard to macrophage subtypes, while in the tumor, the percentage of M2 macrophages was decreased in the cachectic patients, in comparison to weight-stable counterparts. CCL3, CCL4, and IL-1ß expression was higher in the adipose tissue and tumor tissue in the cachectic group. In both tissues, chemotactic factors were positively correlated with IL-1ß. Furthermore, positive correlations were found for the content of chemoattractants and cytokines in the tumor and adipose tissue. The results strongly suggest that the crosstalk between the tumor and peripheral tissues is more pronounced in cachectic patients, compared to weight-stable patients with the same tumor diagnosis.