RESUMO
The side effects of cancer therapy continue to cause significant health and cost burden to the patient, their friends and family, and governments. A major barrier in the way in which these side effects are managed is the highly siloed mentality that results in a fragmented approach to symptom control. Increasingly, it is appreciated that many symptoms are manifestations of common underlying pathobiology, with changes in the gastrointestinal environment a key driver for many symptom sequelae. Breakdown of the mucosal barrier (mucositis) is a common and early side effect of many anti-cancer agents, known to contribute (in part) to a range of highly burdensome symptoms such as diarrhoea, nausea, vomiting, infection, malnutrition, fatigue, depression, and insomnia. Here, we outline a rationale for how, based on its already documented effects on the gastrointestinal microenvironment, medicinal cannabis could be used to control mucositis and prevent the constellation of symptoms with which it is associated. We will provide a brief update on the current state of evidence on medicinal cannabis in cancer care and outline the potential benefits (and challenges) of using medicinal cannabis during active cancer therapy.
Assuntos
Maconha Medicinal , Mucosite , Neoplasias , Humanos , Maconha Medicinal/efeitos adversos , Mucosite/tratamento farmacológico , Neoplasias/tratamento farmacológico , Náusea/induzido quimicamente , Náusea/tratamento farmacológico , Vômito , Microambiente TumoralRESUMO
Childhood is recognised as a period of immense physical and emotional development, and this, in part, is driven by underlying neurophysiological transformations. These neurodevelopmental processes are unique to the paediatric brain and are facilitated by augmented rates of neuroplasticity and expanded neural stem cell populations within neurogenic niches. However, given the immaturity of the developing central nervous system, innate protective mechanisms such as neuroimmune and antioxidant responses are functionally naïve which results in periods of heightened sensitivity to neurotoxic insult. This is highly relevant in the context of paediatric cancer, and in particular, the neurocognitive symptoms associated with treatment, such as surgery, radio- and chemotherapy. The vulnerability of the developing brain may increase susceptibility to damage and persistent symptomology, aligning with reports of more severe neurocognitive dysfunction in children compared to adults. It is therefore surprising, given this intensified neurocognitive burden, that most of the pre-clinical, mechanistic research focuses exclusively on adult populations and extrapolates findings to paediatric cohorts. Given this dearth of age-specific research, throughout this review we will draw comparisons with neurodevelopmental disorders which share comparable pathways to cancer treatment related side-effects. Furthermore, we will examine the unique nuances of the paediatric brain along with the somatic systems which influence neurological function. In doing so, we will highlight the importance of developing in vitro and in vivo paediatric disease models to produce age-specific discovery and clinically translatable research.
Assuntos
Encefalopatias , Comprometimento Cognitivo Relacionado à Quimioterapia , Neoplasias , Adulto , Criança , Humanos , EncéfaloRESUMO
Microbiome science has been one of the most exciting and rapidly evolving research fields in the past two decades. Breakthroughs in technologies including DNA sequencing have meant that the trillions of microbes (particularly bacteria) inhabiting human biological niches (particularly the gut) can be profiled and analysed in exquisite detail. This microbiome profiling has profound impacts across many fields of research, especially biomedical science, with implications for how we understand and ultimately treat a wide range of human disorders. However, like many great scientific frontiers in human history, the pioneering nature of microbiome research comes with a multitude of challenges and potential pitfalls. These include the reproducibility and robustness of microbiome science, especially in its applications to human health outcomes. In this article, we address the enormous promise of microbiome science and its many challenges, proposing constructive solutions to enhance the reproducibility and robustness of research in this nascent field. The optimisation of microbiome science spans research design, implementation and analysis, and we discuss specific aspects such as the importance of ecological principals and functionality, challenges with microbiome-modulating therapies and the consideration of confounding, alternative options for microbiome sequencing, and the potential of machine learning and computational science to advance the field. The power of microbiome science promises to revolutionise our understanding of many diseases and provide new approaches to prevention, early diagnosis, and treatment.
Assuntos
Microbiota , Humanos , Reprodutibilidade dos Testes , Aprendizado de MáquinaRESUMO
OBJECTIVE: As the Internet is a ubiquitous resource for information, we aimed to replicate a patient's Google search to identify and assess the quality of online mental health/wellbeing materials available to support women living with or beyond cancer. METHODS: A Google search was performed using a key term search strategy including search strings 'cancer', 'wellbeing', 'distress' and 'resources' to identify online resources of diverse formats (i.e., factsheet, website, program, course, video, webinar, e-book, podcast). The quality evaluation scoring tool (QUEST) was used to analyse the quality of health information provided. RESULTS: The search strategy resulted in 283 resources, 117 of which met inclusion criteria across four countries: Australia, USA, UK, and Canada. Websites and factsheets were primarily retrieved. The average QUEST score was 10.04 (highest possible score is 28), indicating low quality, with 92.31% of resources lacking references to sources of information. CONCLUSIONS: Our data indicated a lack of evidence-based support resources and engaging information available online for people living with or beyond cancer. The majority of online resources were non-specific to breast cancer and lacked authorship and attribution.
Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/terapia , Saúde Mental , Ferramenta de Busca , Internet , SobreviventesRESUMO
Advances in the treatment of cancer have significantly improved mortality rates; however, this has come at a cost, with many treatments still limited by their toxic side effects. Mucositis in both the mouth and gastrointestinal tract is common following many anti-cancer agents, manifesting as ulcerative lesions and associated symptoms throughout the alimentary tract. The pathogenesis of mucositis was first defined in 2004 by Sonis, and almost 20 years on, the model continues to be updated reflecting ongoing research initiatives and more sophisticated analytical techniques. The most recent update, published by the Multinational Association for Supportive Care in Cancer and the International Society for Oral Oncology (MASCC/ISOO), highlights the numerous co-occurring events that underpin mucositis development. Most notably, a role for the ecosystem of microorganisms that reside throughout the alimentary tract (the oral and gut microbiota) was explored, building on initial concepts proposed by Sonis. However, many questions remain regarding the true causal contribution of the microbiota and associated metabolome. This review aims to provide an overview of this rapidly evolving area, synthesizing current evidence on the microbiota's contribution to mucositis development and progression, highlighting (i) components of the 5-phase model where the microbiome may be involved, (ii) methodological challenges that have hindered advances in this area, and (iii) opportunities for intervention.
Assuntos
Antineoplásicos , Microbioma Gastrointestinal , Mucosite , Humanos , Microbioma Gastrointestinal/fisiologia , Antineoplásicos/efeitos adversos , Mucosite/microbiologia , Mucosite/etiologia , Neoplasias/complicações , Microbiota , Estomatite/microbiologia , Estomatite/etiologia , Progressão da DoençaRESUMO
NEW FINDINGS: What is the central question of this study? Body mass and food intake change during the female ovarian cycle: does glucose transport by the small intestine also vary? What is the main finding and its importance? We have optimised Ussing chamber methodology to measure region-specific active glucose transport in the small intestine of adult C57BL/6 mice. Our study provides the first evidence that jejunal active glucose transport changes during the oestrous cycle in mice, and is higher at pro-oestrus than oestrus. These results demonstrate adaptation in active glucose uptake, concurrent with previously reported changes in food intake. ABSTRACT: Food intake changes across the ovarian cycle in rodents and humans, with a nadir during the pre-ovulatory phase and a peak during the luteal phase. However, it is unknown whether the rate of intestinal glucose absorption also changes. We therefore mounted small intestinal sections from C57BL/6 female mice (8-9 weeks old) in Ussing chambers and measured active ex vivo glucose transport via the change in short-circuit current (∆Isc ) induced by glucose. Tissue viability was confirmed by a positive ∆Isc response to 100 µM carbachol following each experiment. Active glucose transport, assessed after addition of 5, 10, 25 or 45 mM d-glucose to the mucosal chamber, was highest at 45 mM glucose in the distal jejunum compared to duodenum and ileum (P < 0.01). Incubation with the sodium-glucose cotransporter 1 (SGLT1) inhibitor phlorizin reduced active glucose transport in a dose-dependent manner in all regions (P < 0.01). Active glucose uptake induced by addition of 45 mM glucose to the mucosal chamber in the absence or presence of phlorizin was assessed in jejunum at each oestrous cycle stage (n = 9-10 mice per stage). Overall, active glucose uptake was lower at oestrus compared to pro-oestrus (P = 0.025). This study establishes an ex vivo method to measure region-specific glucose transport in the mouse small intestine. Our results provide the first direct evidence that SGLT1-mediated glucose transport in the jejunum changes across the ovarian cycle. The mechanisms underlying these adaptations in nutrient absorption remain to be elucidated.
Assuntos
Glucose , Florizina , Humanos , Feminino , Animais , Camundongos , Glucose/metabolismo , Florizina/metabolismo , Camundongos Endogâmicos C57BL , Intestino Delgado/metabolismo , Jejuno , Absorção Intestinal , Mucosa Intestinal/metabolismoRESUMO
Gastrointestinal mucositis could potentially compromise drug absorption due to functional loss of mucosa and other pathophysiological changes in the gastrointestinal microenvironment. Little is known about this effect on commonly used anti-infectives. This study aimed to explore the association between different stages of gastrointestinal mucositis, drug exposure, and gut microbiota. A prospective, observational pilot study was performed in HSCT patients aged ≥ 18 years receiving anti-infectives orally. Left-over blood samples and fecal swabs were collected from routine clinical care until 14 days after HSCT to analyze drug and citrulline concentrations and to determine the composition of the gut microbiota. 21 patients with a median age of 58 (interquartile range 54-64) years were included with 252 citrulline, 155 ciprofloxacin, 139 fluconazole, and 76 acyclovir concentrations and 48 fecal swabs obtained. Severe gastrointestinal mucositis was observed in all patients. Due to limited data correlation analysis was not done for valacyclovir and fluconazole, however we did observe a weak correlation between ciprofloxacin and citrulline concentrations. This could suggest that underexposure of ciprofloxacin can occur during severe mucositis. A follow-up study using frequent sampling rather than the use of left-over would be required to investigate the relationship between gastrointestinal mucositis, drug exposure, and gut microbiome.
Assuntos
Anti-Infecciosos , Microbioma Gastrointestinal , Mucosite , Humanos , Pessoa de Meia-Idade , Mucosite/induzido quimicamente , Projetos Piloto , Fluconazol/efeitos adversos , Seguimentos , Estudos Prospectivos , Citrulina/farmacologia , Transplante de Células-Tronco , Anti-Infecciosos/efeitos adversos , Ciprofloxacina/efeitos adversosRESUMO
PURPOSE: Growing recognition of the gut microbiome as an influential modulator of cancer treatment efficacy and toxicity has led to the emergence of clinical interventions targeting the microbiome to enhance cancer and health outcomes. The highly modifiable nature of microbiota to endogenous, exogenous, and environmental inputs enables interventions to promote resilience of the gut microbiome that have rapid effects on host health, or response to cancer treatment. While diet, probiotics, and faecal microbiota transplant are primary avenues of therapy focused on restoring or protecting gut function in people undergoing cancer treatment, the role of physical activity and exercise has scarcely been examined in this population. METHODS: A narrative review was conducted to explore the nexus between cancer care and the gut microbiome in the context of physical activity and exercise as a widely available and clinically effective supportive care strategy used by cancer survivors. RESULTS: Exercise can facilitate a more diverse gut microbiome and functional metabolome in humans; however, most physical activity and exercise studies have been conducted in healthy or athletic populations, primarily using aerobic exercise modalities. A scarcity of exercise and microbiome studies in cancer exists. CONCLUSIONS: Exercise remains an attractive avenue to promote microbiome health in cancer survivors. Future research should elucidate the various influences of exercise modalities, intensities, frequencies, durations, and volumes to explore dose-response relationships between exercise and the gut microbiome among cancer survivors, as well as multifaceted approaches (such as diet and probiotics), and examine the influences of exercise on the gut microbiome and associated symptom burden prior to, during, and following cancer treatment.
Assuntos
Microbioma Gastrointestinal , Neoplasias , Probióticos , Esportes , Humanos , Microbioma Gastrointestinal/fisiologia , Exercício Físico/fisiologia , Neoplasias/terapia , Dieta , Probióticos/uso terapêuticoRESUMO
Oral mucositis (OM) is a common and impactful toxicity of standard cancer therapy, affecting up to 80% of patients. Its aetiology centres on the initial destruction of epithelial cells and the increase in inflammatory signals. These changes in the oral mucosa create a hostile environment for resident microbes, with oral infections co-occurring with OM, especially at sites of ulceration. Increasing evidence suggests that oral microbiome changes occur beyond opportunistic infection, with a growing appreciation for the potential role of the microbiome in OM development and severity. This review collects the latest articles indexed in the PubMed electronic database which analyse the bacterial shift through 16S rRNA gene sequencing methodology in cancer patients under treatment with oral mucositis. The aims are to assess whether changes in the oral and gut microbiome causally contribute to oral mucositis or if they are simply a consequence of the mucosal injury. Further, we explore the emerging role of a patient's microbial fingerprint in OM development and prediction. The maintenance of resident bacteria via microbial target therapy is under constant improvement and should be considered in the OM treatment.
Assuntos
Microbiota , Mucosite , Neoplasias , Estomatite , Humanos , RNA Ribossômico 16S/genética , Estomatite/patologia , Mucosa Bucal/patologia , Neoplasias/patologia , Bactérias , Mucosite/patologiaRESUMO
The efficacy of immune checkpoint inhibitors (immunotherapy) is increasingly recognized to be linked to the composition the gut microbiome. Given the high rates of resistance, interventions targeting the gut microbiome are now being investigated for its ability to improve the efficacy of immunotherapy. In light of recently published data demonstrating a strong correlation between the efficacy and toxicity of immunotherapy, there is a risk that efforts to enhance immunotherapy efficacy may be undermined by increases in immune-related adverse events (IrAEs) This is particularly important for microbial interventions aimed at increasing immunotherapy efficacy, with many microbes implicated in tumour response also linked to IrAEs, especially colitis. IrAEs have a profound impact on patient quality of life, causing physical, psychosocial, and financial distress. Here, we outline strategies at the discovery, translational, and clinical research phases to ensure the impact of augmenting immunotherapy efficacy is approached in a manner that considers adverse implications. Adopting these strategies will ensure that our ongoing efforts to overcome immunotherapy resistance are not impacted by unacceptable toxicity.
Assuntos
Microbioma Gastrointestinal , Neoplasias , Humanos , Fatores Imunológicos/uso terapêutico , Imunoterapia/efeitos adversos , Neoplasias/tratamento farmacológico , Qualidade de VidaRESUMO
INTRODUCTION: Engaging with patients and the public (consumers and community) enhances the relevance of cancer control developments; however, challenges remain to integrate into processes. Medical and other professional societies are well-positioned to foster and endorse best practice. METHODS: Between October and December 2021, the Multinational Association of Supportive Care in Cancer (MASCC) conducted a global consultation with those who identified as "people affected by cancer". Recruitment to an online cross-sectional survey was by a combination of purposive and convenience sampling to determine preferred terminologies and experiences with MASCC and other cancer-related societies. RESULTS: The survey was completed by 343 respondents from 29 countries, a majority being female (78.1%) and younger than 60 years of age (62.1%). Respondents preferred to be identified as 'patient' from a set of defined terms; however, this only accounted for 49-67% of selected response across geographical regions. Only 22.2% of respondents had engaged previously with MASCC, of whom 90.8% reported a positive experience through involvement with education and information, networking and collaboration, and practice guidelines. Respondents perceived areas of opportunity as early involvement in decision-making, educational initiatives, open communication, and information sharing. Across all geographical regions, responders chose a preference to contribute to future consumer research (53.0%), policy (31.7%) or consumer engagement activities (56.9%) including participation in a conference session (65.0%) or patient day (47.9%). CONCLUSIONS: This survey provides a first insight into how consumers wish to engage with MASCC. These values will be embedded into a strategy that aims for effective and sustainable partnerships with multinational consumers.
Assuntos
Neoplasias , Participação do Paciente , Humanos , Feminino , Masculino , Estudos Transversais , Comunicação , Neoplasias/terapia , Encaminhamento e ConsultaRESUMO
Toll-like receptor 4 (TLR4) is a highly conserved protein of innate immunity, responsible for the regulation and maintenance of homeostasis, as well as immune recognition of external and internal ligands. TLR4 is expressed on a variety of cell types throughout the gastrointestinal tract, including on epithelial and immune cell populations. In a healthy state, epithelial cell expression of TLR4 greatly assists in homeostasis by shaping the host microbiome, promoting immunoglobulin A production, and regulating follicle-associated epithelium permeability. In contrast, immune cell expression of TLR4 in healthy states is primarily centred on the maturation of dendritic cells in response to stimuli, as well as adequately priming the adaptive immune system to fight infection and promote immune memory. Hence, in a healthy state, there is a clear distinction in the site-specific roles of TLR4 expression. Similarly, recent research has indicated the importance of site-specific TLR4 expression in inflammation and disease, particularly the impact of epithelial-specific TLR4 on disease progression. However, the majority of evidence still remains ambiguous for cell-specific observations, with many studies failing to provide the distinction of epithelial versus immune cell expression of TLR4, preventing specific mechanistic insight and greatly impacting the translation of results. The following review provides a critical overview of the current understanding of site-specific TLR4 activity and its contribution to intestinal/immune homeostasis and inflammatory diseases.
Assuntos
Homeostase/fisiologia , Inflamação/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/patologia , Receptor 4 Toll-Like/metabolismo , Animais , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Humanos , Inflamação/patologiaRESUMO
Chemotherapy-induced gastrointestinal toxicity (CIGT) occurs in up to 80% of all patients undergoing cancer treatment, and leads to symptoms such as diarrhoea, abdominal bleeding and pain. There is currently limited understanding of how to predict an individual patient's risk of CIGT. It is believed the gut microbiome and its interactions with the host's innate immune system plays a key role in the development of this toxicity and potentially other toxicities, however comprehensive bioinformatics modelling has not been rigorously performed. The innate immune system is strongly influenced by the microbial environment and vice-versa. Ways this may occur include the immune system controlling composition and compartmentalisation of the microbiome, the microbiome affecting development of antigen-presenting cells, and finally, the NLRP6 inflammasome orchestrating the colonic host-microbiome interface. This evidence calls into question the role of pre-treatment risk factors in the development of gastrointestinal toxicity after chemotherapy. This review aims to examine evidence of a bidirectional interaction between the gut microbiome and innate immunity, and how these interactions occur in CIGT. In the future, knowledge of these interactions may lead to improved personalised cancer medicine, predictive risk stratification methods and the development of targeted interventions to reduce, or even prevent, CIGT severity.
Assuntos
Antineoplásicos/efeitos adversos , Gastroenteropatias/induzido quimicamente , Gastroenteropatias/imunologia , Microbioma Gastrointestinal/imunologia , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/microbiologia , Imunidade Inata/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Gastroenteropatias/microbiologia , Humanos , Sistema Imunitário/imunologia , Microbiota/imunologia , Neoplasias/tratamento farmacológico , Neoplasias/imunologiaRESUMO
PURPOSE: The aim of this study was to update the clinical practice guidelines for the use of agents for the prevention and/or treatment of gastrointestinal mucositis (GIM). METHODS: A systematic review was conducted by the Mucositis Study Group of the Multinational Association of Supportive Care in Cancer/International Society for Oral Oncology (MASCC/ISOO). The body of evidence for each intervention, in each cancer treatment setting, was assigned an evidence level. Based on the evidence level, one of the following three guideline determinations was possible: Recommendation, Suggestion, and No Guideline Possible. RESULTS: A total of 78 papers across 13 interventions were examined of which 25 were included in the final review. No new guidelines were possible for any agent due to inadequate and/or conflicting evidence. Existing guidelines for probiotics and hyperbaric oxygen were unchanged. CONCLUSIONS: Of the agents studied for the prevention and treatment of GIM, the evidence continues to support use of probiotics containing Lactobacillus spp. for prevention of chemoradiotherapy and radiotherapy-induced diarrhea in patients with pelvic malignancy, and hyperbaric oxygen therapy to treat radiation-induced proctitis. Additional well-designed research is encouraged to enable a decision regarding palifermin, glutamine, sodium butyrate, and dietary interventions, for the prevention or treatment of GIM.
Assuntos
Quimiorradioterapia/efeitos adversos , Mucosite/tratamento farmacológico , Mucosite/prevenção & controle , Guias de Prática Clínica como Assunto , Proctite/tratamento farmacológico , Estomatite/tratamento farmacológico , Ácido Butírico/uso terapêutico , Fator 7 de Crescimento de Fibroblastos/uso terapêutico , Glutamina/uso terapêutico , Humanos , Oxigenoterapia Hiperbárica , Neoplasias/tratamento farmacológicoRESUMO
Dacomitinib, an irreversible small-molecule pan-ErbB TKI, has a high incidence of diarrhea, which has been suggested to be due to chloride secretory mechanisms. Based on this hypothesis, crofelemer, an antisecretory agent may be an effective intervention. T84 monolayers were treated with 1 µM dacomitinib and 10 µM crofelemer, and mounted into Ussing chambers for electrogenic ion analysis. Crofelemer attenuated increases in chloride secretion in cells treated with dacomitinib. Albino Wistar rats (n = 48) were treated with 7.5 mg/kg dacomitinib and/or 25 mg/kg crofelemer via oral gavage for 21 days. Crofelemer significantly worsened dacomitinib-induced diarrhea (p = 0.0003), and did not attenuate weight loss (p < 0.0001). Sections of the ileum and colon were mounted into Ussing chambers, and secretory processes analyzed. This indicated that crofelemer lost its anti-secretory action in the presence of dacomitinib in this model. Mass spectrometry revealed that crofelemer did not change serum concentration of dacomitinib. Serum FITC dextran levels indicated that crofelemer was unable to attenuate dacomitinib-induced barrier dysfunction. Tight junction proteins were visualized with immunofluorescence. Qualitative analysis showed dacomitinib induced proteolysis of ZO-1 and occludin, and internalization of claudin-1, which was not attenuated by crofelemer. Detailed histopathological analysis showed that crofelemer was unable to attenuate dacomitinib-induced ileal damage. Crofelemer worsened dacomitinib-induced diarrhea, suggesting that antisecretory drug therapy may be ineffective in this setting.
Assuntos
Cloretos/metabolismo , Diarreia/tratamento farmacológico , Proantocianidinas/farmacologia , Quinazolinonas/toxicidade , Animais , Permeabilidade da Membrana Celular/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Diarreia/induzido quimicamente , Diarreia/metabolismo , Eletrofisiologia , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/patologia , Humanos , Masculino , Ratos , Ratos Wistar , Células Tumorais Cultivadas , Redução de Peso/efeitos dos fármacosRESUMO
BACKGROUND: The common cytotoxic mechanisms that underpin chemoefficacy and toxicity have hampered efforts to deliver effective supportive care interventions, particularly for gastrointestinal (GI) toxicity. Matrix metalloproteinases (MMPs) have been implicated in both tumor growth and GI toxicity, and as such MMP inhibitors present as a novel therapeutic avenue to simultaneously enhance treatment efficacy and reduce toxicity. OBJECTIVES: The aim of this study was to determine the efficacy of an MMP-9/12 inhibitor, AZD3342, on tumor growth and GI toxicity in a rat model. METHODS: Female tumor-bearing Dark Agouti rats (n = 90) were divided into 4 groups: vehicle control; methotrexate (MTX); AZD3342, and MTX + AZD3342. Tumors were measured daily (for 5 days) using digital calipers. GI toxicity was assessed using well-established clinical markers (diarrhea/weight loss), histopathological analysis, and functional assessment of intestinal barrier permeability. RESULTS: AZD3342 delayed the onset of severe diarrhea by 1 day (vs. MTX) but was unable to improve the overall severity of diarrhea. No changes were detected in tissue morphology or intestinal barrier function. AZD3342 alone suppressed tumor growth (p = 0.003 vs. vehicle) but did not enhance the efficacy of MTX. CONCLUSIONS: This study showed partial efficacy of AZD3342 in reducing tumor growth and delaying the onset of severe diarrhea caused by MTX in rats. We suggest further studies be undertaken targeting appropriate scheduling of AZD3342 as well as investigating different cytotoxic therapies that strongly activate MMP signaling.
Assuntos
Inibidores de Metaloproteinases de Matriz/uso terapêutico , Neoplasias/tratamento farmacológico , Compostos Orgânicos/uso terapêutico , Animais , Antimetabólitos Antineoplásicos/efeitos adversos , Antimetabólitos Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Diarreia/etiologia , Feminino , Humanos , Mucosa Intestinal/patologia , Inibidores de Metaloproteinases de Matriz/efeitos adversos , Metaloproteinases da Matriz/química , Metaloproteinases da Matriz/metabolismo , Metotrexato/efeitos adversos , Metotrexato/uso terapêutico , Neoplasias/patologia , Compostos Orgânicos/efeitos adversos , Distribuição Aleatória , Ratos , Transplante HeterólogoRESUMO
Inflammatory bowel disease (IBD) is characterized by chronic remitting and relapsing inflammation of the lower gastrointestinal tract. The etiology underlying IBD remains unknown, but it is thought to involve a hypersensitive immune response to environmental antigens, including the microbiota. Diagnosis and monitoring of IBD is heavily reliant on endoscopy, which is invasive and does not provide information regarding specific mediators. This review describes recent developments in imaging of IBD with a focus on positron emission tomography (PET) and single-photon emission computed tomography (SPECT) of inflammatory mediators, and how these developments may be applied to the microbiota.
Assuntos
Citocinas/análise , Imunoglobulina G/análise , Doenças Inflamatórias Intestinais/diagnóstico por imagem , Integrinas/análise , Intestinos/diagnóstico por imagem , Animais , Citocinas/genética , Citocinas/imunologia , Modelos Animais de Doenças , Endoscopia Gastrointestinal , Fluordesoxiglucose F18/farmacocinética , Microbioma Gastrointestinal/imunologia , Expressão Gênica , Humanos , Imunoglobulina G/genética , Imunoglobulina G/metabolismo , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/microbiologia , Integrinas/genética , Integrinas/imunologia , Intestinos/imunologia , Intestinos/microbiologia , Camundongos , Tomografia por Emissão de Pósitrons , Coelhos , Tomografia Computadorizada de Emissão de Fóton ÚnicoRESUMO
Dacomitinib-an irreversible pan-ErbB tyrosine kinase inhibitor (TKI)-causes diarrhoea in 75% of patients. Dacomitinib-induced diarrhoea has not previously been investigated and the mechanisms remain poorly understood. The present study aimed to develop an in-vitro and in-vivo model of dacomitinib-induced diarrhoea to investigate underlying mechanisms. T84 cells were treated with 1-4 µM dacomitinib and resistance and viability were measured using transepithelial electrical resistance (TEER) and XTT assays. Rats were treated with 7.5 mg/kg dacomitinib daily via oral gavage for 7 or 21 days (n = 6/group). Weights, and diarrhoea incidence were recorded daily. Rats were administered FITC-dextran 2 hr before cull, and serum levels of FITC-dextran were measured and serum biochemistry analysis was conducted. Detailed histopathological analysis was conducted throughout the gastrointestinal tract. Gastrointestinal expression of ErbB1, ErbB2 and ErbB4 was analysed using RT-PCR. The ileum and the colon were analysed using multiplex for expression of various cytokines. T84 cells treated with dacomitinib showed no alteration in TEER or cell viability. Rats treated with dacomitinib developed severe diarrhoea, and had significantly lower weight gain. Further, dacomitinib treatment led to severe histopathological injury localised to the ileum. This damage coincided with increased levels of MCP1 in the ileum, and preferential expression of ErbB1 in this region compared to all other regions. This study showed dacomitinib induces severe ileal damage accompanied by increased MCP1 expression, and gastrointestinal permeability in rats. The histological changes were most pronounced in the ileum, which was also the region with the highest relative expression of ErbB1.
Assuntos
Diarreia/induzido quimicamente , Trato Gastrointestinal/efeitos dos fármacos , Íleo/efeitos dos fármacos , Quinazolinonas/toxicidade , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Quimiocina CCL2/metabolismo , Neoplasias Colorretais/patologia , Diarreia/fisiopatologia , Modelos Animais de Doenças , Receptores ErbB/genética , Receptores ErbB/metabolismo , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/fisiopatologia , Expressão Gênica/efeitos dos fármacos , Humanos , Íleo/metabolismo , Íleo/fisiopatologia , Imuno-Histoquímica , Masculino , Permeabilidade/efeitos dos fármacos , Quinazolinonas/farmacologia , Ensaio de Radioimunoprecipitação , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Neurotoxicity is a common side effect of chemotherapy treatment, with unclear molecular mechanisms. Clinical studies suggest that the most frequent neurotoxic adverse events affect memory and learning, attention, concentration, processing speeds and executive function. Emerging preclinical research points toward direct cellular toxicity and induction of neuroinflammation as key drivers of neurotoxicity and subsequent cognitive impairment. Emerging data now show detectable levels of some chemotherapeutic agents within the CNS, indicating potential disruption of blood brain barrier integrity or transport mechanisms. Blood brain barrier disruption is a key aspect of many neurocognitive disorders, particularly those characterized by a proinflammatory state. Importantly, many proinflammatory mediators able to modulate the blood brain barrier are generated by tissues and organs that are targets for chemotherapy-associated toxicities. This review therefore aims to explore the hypothesis that peripherally derived inflammatory cytokines disrupt blood brain barrier permeability, thereby increasing direct access of chemotherapeutic agents into the CNS to facilitate neuroinflammation and central neurotoxicity.