RESUMEN
BACKGROUND: A significant proportion of inflammatory bowel disease (IBD) patients fail to respond to advanced therapies. Combining advanced therapies may improve treatment outcome. This study aimed to assess the effectiveness, adverse events, and costs associated with combining advanced therapies in IBD patients. METHODS: Combination advanced therapy was defined as the concurrent use of two biological agents or one biological agent with a small molecule therapy. Clinical data, including disease characteristics, treatment regimens, and adverse events, were collected from electronic patient records. Clinical response rates, biochemical markers, and treatment costs were evaluated. RESULTS: The study included 109 IBD patients receiving combination advanced therapies from 9 academic centers in Ireland. Corticosteroid-free clinical response rates at 12 weeks and 52 weeks were 39 % and 38 %, respectively. Adverse events occurred in 26 % of therapeutic trials, with disease-related events being the most common. Notably, there were 3 cases of non-melanomatous skin cancer and 10 infectious complications. The annual cost of maintenance therapy for combination advanced therapies ranged from 17,560 to 30,724 per patient. CONCLUSION: Combination advanced therapies demonstrated effectiveness and acceptable safety profiles in a cohort of treatment-refractory IBD patients. Further large, prospective trials are required to definitively evaluate the role of combination advanced therapies in IBD.
RESUMEN
CMS4 colorectal cancer (CRC), based on the consensus molecular subtype (CMS), stratifies patients with the poorest disease-free survival rates. It is characterized by a strong mesenchymal stromal cell (MSC) signature, wound healing-like inflammation and therapy resistance. We utilized 2D and 3D in vitro, in vivo, and ex vivo models to assess the impact of inflammation and stromal cells on immunosuppression in CMS4 CRC. RNA sequencing data from untreated stage II/III CRC patients showed enriched TNF-α signatures in CMS1 and CMS4 tumors. Secretome from TNF-α treated cancer cells induced an immunomodulatory and chemotactic phenotype in MSC and cancer-associated fibroblasts (CAFs). Macrophages in CRC tumours migrate and preferentially localise in stromal compartment. Inflammatory CRC secretome enhances expression of PD-L1 and CD47 on both human and murine stromal cells. We demonstrate that TNF-α-induced inflammation in CRC suppresses macrophage phagocytosis via stromal cells. We show that stromal cell-mediated suppression of macrophage phagocytosis is mediated in part through PD-1 signaling. These data suggest that re-stratification of CRC by CMS may reveal patient subsets with microsatellite stable tumors, particularly CMS4-like tumors, that may respond to immunotherapies.
RESUMEN
Immunosuppressive tumor microenvironments (TMEs) reduce the effectiveness of immune responses in cancer. Mesenchymal stromal cells (MSCs), precursors to cancer-associated fibroblasts (CAFs), promote tumor progression by enhancing immune cell suppression in colorectal cancer (CRC). Hyper-sialylation of glycans promotes immune evasion in cancer through binding of sialic acids to their receptors, Siglecs, expressed on immune cells, which results in inhibition of effector functions. The role of sialylation in shaping MSC/CAF immunosuppression in the TME is not well characterized. In this study, we show that tumor-conditioned stromal cells have increased sialyltransferase expression, α2,3/6-linked sialic acid, and Siglec ligands. Tumor-conditioned stromal cells and CAFs induce exhausted immunomodulatory CD8+ PD1+ and CD8+ Siglec-7+/Siglec-9+ T cell phenotypes. In vivo, targeting stromal cell sialylation reverses stromal cell-mediated immunosuppression, as shown by infiltration of CD25 and granzyme B-expressing CD8+ T cells in the tumor and draining lymph node. Targeting stromal cell sialylation may overcome immunosuppression in the CRC TME.
Asunto(s)
Fibroblastos Asociados al Cáncer , Neoplasias , Humanos , Linfocitos T CD8-positivos , Microambiente Tumoral , Terapia de Inmunosupresión , Células del Estroma/metabolismo , Neoplasias/patología , Fibroblastos Asociados al Cáncer/metabolismo , Lectinas Similares a la Inmunoglobulina de Unión a Ácido Siálico/metabolismoRESUMEN
Gastroesophageal reflux disease (GERD) is one the most common medical complaints in pregnant women. Some women continue to experience GERD symptoms after delivery. Effective management of GERD symptoms is important to improve productivity and quality of life. Management of heartburn in pregnant and breastfeeding women involves lifestyle modifications, dietary modifications, non-pharmaceutical remedies and pharmaceutical drugs. For most patients, lifestyle/dietary modifications are helpful in reducing GERD symptoms. For patients who require a more intense intervention, various types of pharmaceutical drugs are available. However, the suitability of each treatment for use during pregnancy and lactation must be taken into consideration. This article explores the reported efficacy and safety of these treatment options in pregnant and breastfeeding women. Recommended treatment algorithm in pregnant and breastfeeding women have been developed.
Asunto(s)
Reflujo Gastroesofágico , Complicaciones del Embarazo , Lactancia Materna , Femenino , Reflujo Gastroesofágico/tratamiento farmacológico , Pirosis/tratamiento farmacológico , Pirosis/terapia , Humanos , Preparaciones Farmacéuticas , Embarazo , Complicaciones del Embarazo/terapia , Calidad de VidaRESUMEN
Delivering drugs directly to the inflamed intestinal sites to treat inflammatory bowel disease (IBD), particularly Crohn's and ulcerative colitis, is highly challenging. Recent advances in colitis therapy medications are expanding opportunities for improving local on-site drug availability by minimising the associated systemic side-effects. Drug delivery with targeted carrier systems has shown the potential to increase site-specificity, stability, and therapeutic efficacy. Herein, we report the development of a strong anionic charged inflammation targeted nanocarriers (IT-NCs) loaded with an immunosuppressant model drug. This system showed preferential adhesion on a charge-modified surface in vitro, and in both dextran sulfate sodium (DSS) and TNBS colitis mice in vivo models. IT-NCs showed improved colitis phenotype therapeutic efficacy in both animal models compared to free drug. Furthermore, ex vivo study of colon tissue biopsies from patients with colitis revealed that IT-NCs adhered preferentially to inflamed biopsies compared to normal. Together, our results suggest that IT-NCs have promising therapeutic potential as delivery carriers' in colitis management.
Asunto(s)
Colitis Ulcerosa , Colitis , Enfermedades Inflamatorias del Intestino , Animales , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/patología , Colon/patología , Sulfato de Dextran , Modelos Animales de Enfermedad , Portadores de Fármacos/uso terapéutico , Humanos , Inflamación/tratamiento farmacológico , Inflamación/patología , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/patología , Mucosa Intestinal , RatonesRESUMEN
Non-steroidal anti-inflammatory drugs (NSAIDs) can cause small bowel damage, which could present in different ways, including abdominal pain and occult gastrointestinal bleeding. NSAID use can also result in small bowel strictures, which can be challenging to diagnose and manage. Here, we describe a case of a 49-year-old female who presented with chronic anaemia and intermittent abdominal pain, with a history of NSAID use. She underwent capsule endoscopy as part of the workup for anaemia and subsequently had capsule retention due to a small bowel stricture.
RESUMEN
BACKGROUND: The initial operation of choice in many patients presenting as an emergency with ulcerative colitis is a subtotal colectomy with end ileostomy. A percentage of patients do not proceed to completion proctectomy with ileal pouch anal anastomosis. AIM: To review the existing literature in relation to the significant long-term complic-ations associated with the rectal stump, to provide an overview of options for the surgical management of remnant rectum and anal canal and to form a consolidated guideline on endoscopic screening recommendations in this cohort. METHODS: A systematic review was carried out in accordance with PRISMA guidelines for papers containing recommendations for endoscopy surveillance in rectal remnants in ulcerative colitis. A secondary narrative review was carried out exploring the medical and surgical management options for the retained rectum. RESULTS: For rectal stump surveillance guidelines, 20% recommended an interval of 6 mo to a year, 50% recommended yearly surveillance 10% recommended 2 yearly surveillance and the remaining 30% recommended risk stratification of patients and different screening intervals based on this. All studies agreed surveillance should be carried out via endoscopy and biopsy. Increased vigilance is needed in endoscopy in these patients. Literature review revealed a number of options for surgical management of the remnant rectum. CONCLUSION: The retained rectal stump needs to be surveyed endoscopically according to risk stratification. Great care must be taken to avoid rectal perforation and pelvic sepsis at time of endoscopy. If completion proctectomy is indicated the authors favour removal of the anal canal using an intersphincteric dissection technique.
RESUMEN
INTRODUCTION: Accelerated dose infliximab (IFX) induction is associated with reduced short-term colectomy rate in acute severe ulcerative colitis (ASUC). Data on medium/long-term outcomes of this strategy are limited. AIMS: Evaluate medium/long-term outcomes in patients receiving IFX induction for ASUC, comparing accelerated dose (AD) and standard dose (SD) induction. METHODS: Retrospective study of consecutive patients admitted with corticosteroid-refractory ASUC in four tertiary referral centres within INITIative IBD research network (www.initiativeibd.ie). IFX rescue was given either as SD (weeks 0, 2, 6) or AD (<28 days) from January 2010 to September 2017. AD induction has been utilised in participating centres since 2014. Consequently SD patients were subdivided based on time period of IFX rescue: historical SD group (SD1) (2010-2013) and current SD group (SD2) (2014-2017). Primary endpoint was time to colectomy; secondary endpoint was time to IFX discontinuation if induction was complete. RESULTS: 145 patients received rescue IFX (AD=58, SD1=32, SD2=55). Disease severity at induction was comparable between AD and SD1 groups; however, SD2 group had less severe disease: median C-reactive protein (CRP) 39, 44 and 20 mg/L for AD, SD1 and SD2 groups, respectively (p=0.026, Kruskal-Wallis); median CRP: albumin ratio was 1.4, 1.8 and 0.6 (p=0.016). Median follow-up for AD, SD1 and SD2 groups was 1.6 (IQR 1.1-3.1), 4.9 (IQR 2.6-5.5) and 1.5 (IQR 0.9-2.3) years. Time to colectomy was shorter in SD1 (log rank p=0.0013); no significant difference in time to colectomy was observed comparing AD and SD2 groups (log rank p=0.32). 123 patients (84%) completed IFX induction and received maintenance therapy. Time to IFX discontinuation was shorter in SD1 (log rank p=0.009). CONCLUSION: Time to colectomy is significantly prolonged with use of AD IFX in selected ASUC patients with more severe disease. Historical use of standard IFX induction for all ASUC patients is associated with inferior long-term outcomes.
RESUMEN
p53 is the most frequently mutated, well-studied tumor-suppressor gene, yet the molecular basis of the switch from p53-induced cell-cycle arrest to apoptosis remains poorly understood. Using a combination of transcriptomics and functional genomics, we unexpectedly identified a nodal role for the caspase-8 paralog and only human pseudo-caspase, FLIP(L), in regulating this switch. Moreover, we identify FLIP(L) as a direct p53 transcriptional target gene that is rapidly up-regulated in response to Nutlin-3A, an MDM2 inhibitor that potently activates p53. Genetically or pharmacologically inhibiting expression of FLIP(L) using siRNA or entinostat (a clinically relevant class-I HDAC inhibitor) efficiently promoted apoptosis in colorectal cancer cells in response to Nutlin-3A, which otherwise predominantly induced cell-cycle arrest. Enhanced apoptosis was also observed when entinostat was combined with clinically relevant, p53-activating chemotherapy in vitro, and this translated into enhanced in vivo efficacy. Mechanistically, FLIP(L) inhibited p53-induced apoptosis by blocking activation of caspase-8 by the TRAIL-R2/DR5 death receptor; notably, this activation was not dependent on receptor engagement by its ligand, TRAIL. In the absence of caspase-8, another of its paralogs, caspase-10 (also transcriptionally up-regulated by p53), induced apoptosis in Nutlin-3A-treated, FLIP(L)-depleted cells, albeit to a lesser extent than in caspase-8-proficient cells. FLIP(L) depletion also modulated transcription of canonical p53 target genes, suppressing p53-induced expression of the cell-cycle regulator p21 and enhancing p53-induced up-regulation of proapoptotic PUMA. Thus, even in the absence of caspase-8/10, FLIP(L) silencing promoted p53-induced apoptosis by enhancing PUMA expression. Thus, we report unexpected, therapeutically relevant roles for FLIP(L) in determining cell fate following p53 activation.
Asunto(s)
Proteína Reguladora de Apoptosis Similar a CASP8 y FADD/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Acetilación , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/genética , Benzamidas/farmacología , Caspasa 8/metabolismo , Ciclo Celular/efectos de los fármacos , Ciclo Celular/genética , Línea Celular Tumoral , Sinergismo Farmacológico , Regulación de la Expresión Génica , Humanos , Imidazoles/metabolismo , Modelos Biológicos , Piperazinas/metabolismo , Unión Proteica , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Piridinas/farmacología , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Proteína p53 Supresora de Tumor/genéticaRESUMEN
SUMMARY: This study reviews the safety and efficacy of treatment with vedolizumab for patients with inflammatory bowel disease across 9 Irish hospitals. It generates valuable and timely real-world data on treatment outcomes to add to the existing evidence base. Our population represents a refractory cohort with most patients previously exposed to at least one anti-TNFa agent and expressing an inflammatory phenotype. Results are reassuringly similar to larger international studies with additional insights into potential predictors of treatment response. This study further supports the safety and efficacy of vedolizumab in the treatment of inflammatory bowel disease. Key SummaryVedolizumab has growing real world data on its safety and efficacy in the treatment of IBD. Data on predictors of response are lacking. Studies such as VARSITY require new real-world data to help identify the place VDZ will occupy in the treatment algorithm for IBDThis study provides national Irish data on the safety and efficacy of VDZ in the treatment of IBD. It gives insight into various predictors of response for both UC and CD. It strengthens the available body of evidence on the use of VDZ and helps us determine its position on the treatment algorithm.
Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Colitis Ulcerosa/tratamiento farmacológico , Enfermedad de Crohn/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Irlanda , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Inducción de Remisión , Resultado del Tratamiento , Adulto JovenRESUMEN
Background: Pattern recognition receptors form an essential part of the host defenses against pathogens, in particular in the intestinal epithelium. However, despite their importance relatively little is understood about the regulation of their expression. Increasing evidence suggesting that epigenetic mechanisms such as DNA methylation and histone acetylation have substantial effects on gene expression and regulation. Epigenetic modifying drugs are now used to treat certain cancers but not a lot is known about their effects on the innate immune system. Thus, we set out to examine the role of such drugs in the expression and function of Toll-like receptors. Methods: Using the HCT116 epithelial cell line, we determined the effects of genetic knockout of the DNA methyltransferases enzymes (DNMTs), as well as pharmacological inhibition of the DNMTs and histone deacetylase complexes (HDACs) on TLR responses to their ligands. Results: Our initial results showed that anti-viral responses were affected by changes in the epigenome, with TLR3 responses showing the most dramatic differences. We determined that inhibition of methylation and acetylation inhibited poly I:C induced increases in signaling protein phosphorylation, as well as increases in cytokine mRNA expression and release. We also observed that treatment with epigenetic modifying drugs were leading to large increases in IRF8 expression, a protein that is a known negative regulator of TLR3. When we overexpressed IRF8 in our WT cells we noticed inhibition of poly I:C responses. Conclusion: This research highlighted the potential immunoregulatory role of epigenetic modifying drugs specifically in response to viral stimulation.
Asunto(s)
Antivirales/farmacología , Epigénesis Genética/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Inhibidores de Histona Desacetilasas/farmacología , Poli I-C/farmacología , Receptor Toll-Like 3/metabolismo , ADN (Citosina-5-)-Metiltransferasas/antagonistas & inhibidores , ADN (Citosina-5-)-Metiltransferasas/genética , Metilación de ADN/efectos de los fármacos , Decitabina/farmacología , Células Epiteliales/enzimología , Células Epiteliales/inmunología , Células Epiteliales/virología , Técnicas de Silenciamiento del Gen , Células HCT116 , Histona Desacetilasas/metabolismo , Humanos , Ácidos Hidroxámicos/farmacología , Inmunidad Innata/efectos de los fármacos , Inmunidad Innata/genética , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/enzimología , Mucosa Intestinal/inmunología , Mucosa Intestinal/virología , Proteínas Represoras/antagonistas & inhibidores , Proteínas Represoras/genética , Receptor Toll-Like 3/genética , ADN Metiltransferasa 3BRESUMEN
Stromal cells of mesenchymal origin reside below the epithelial compartment and provide structural support in the intestine. These intestinal stromal cells interact with both the epithelial cell compartments, as well as infiltrating hematopoietic immune cells. The importance of these cells in regulating immune homeostasis during inflammation is well recognized. However, little is known about their function and phenotype in the inflammatory tumor microenvironment. Using a syngeneic, immunogenic model of colorectal cancer, we showed that TNFα-initiated inflammatory signaling in CT26 colorectal cancer cells selectively induced PD-L1 expression in stromal cells. Using CD274 shRNA and antibody-mediated approaches, we showed that stromal cell PD-L1 potentiated enhanced immunosuppression, characterized by inhibition of activated CD8+ granzyme B-secreting T cells in vitro, and the inhibition of CD8+ effector cells was associated with enhanced tumor progression. Stromal cell immunosuppressive and tumor-promoting effects could be reversed with administration of anti-PD-1 in vivo We validated our findings of stromal cell CD274 expression in two cohorts of clinical samples and also observed PD-L1 induction on human stromal cells in response to exposure to the inflammatory secretome from human colon cancer cells, irrespective of microsatellite instability. Collectively, our data showed that tumor-associated stromal cells support T-cell suppression by PD-L1 induction, which is dependent on colon cancer inflammatory signaling. Our findings reveal a key role of mesenchymal stromal cells PD-L1 in suppression of CD8+ antitumor immune responses and potentiation of colorectal cancer progression. Cancer Immunol Res; 6(11); 1426-41. ©2018 AACR.
Asunto(s)
Antígeno B7-H1/metabolismo , Linfocitos T CD8-positivos/inmunología , Neoplasias del Colon/inmunología , Células del Estroma/inmunología , Animales , Antígeno B7-H1/genética , Proliferación Celular , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Femenino , Humanos , Ratones Endogámicos BALB C , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/metabolismo , Células del Estroma/metabolismo , Microambiente Tumoral/inmunología , Factor de Necrosis Tumoral alfa/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND AND AIMS: Golimumab (GLB) is an antitumour necrosis factor-α (anti-TNF) therapy that has shown efficacy as induction and maintenance therapy for ulcerative colitis (UC). We aimed to describe the outcome of GLB therapy for UC in a real-world clinical practice. PATIENTS AND METHODS: Consecutive patients receiving GLB for UC in six Irish Academic Medical Centres were identified. The primary study endpoint was the 6-month corticosteroid-free remission rate. The secondary endpoints included the 3-month clinical response, time free of GLB discontinuation and adverse events. RESULTS: Seventy-two patients were identified [57% men; median (range) age of 41.4 years (20.3-76.8); disease duration 6.6 years (0-29.9); follow-up 8.7 months (0.4-39.2)]. Sixty-four percent of patients were anti-TNF naive. The 3-month clinical response and the 6-month corticosteroid-free remission rates were 55 and 39%, respectively. Forty-four percent of patients discontinued GLB during the follow-up, median (95% confidence interval) time to GLB discontinuation 18.7 months (9.2-28.1). A C-reactive protein more than 5 mg/l at baseline was associated with failure to achieve 6-month corticosteroid-free remission and a shorter time to GLB discontinuation, odds ratio 0.2 (0.1-0.7), P=0.008, and hazard ratio (95% confidence interval) 2.8 (1.3-5.7), P=0.007, respectively. Adverse events occurred in 7% of patients (n=5), all of which were minor and self-limiting. CONCLUSION: These real-world clinical data suggest that GLB is an effective and safe therapy for a UC cohort with significant previous anti-TNF exposure. An elevated baseline C-reactive protein, likely reflective of increased inflammatory burden, is associated with a reduced likelihood of a successful outcome of GLB therapy.
Asunto(s)
Antiinflamatorios/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Colitis Ulcerosa/tratamiento farmacológico , Fármacos Gastrointestinales/uso terapéutico , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Centros Médicos Académicos , Corticoesteroides/uso terapéutico , Adulto , Anciano , Antiinflamatorios/efectos adversos , Anticuerpos Monoclonales/efectos adversos , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Colitis Ulcerosa/sangre , Colitis Ulcerosa/diagnóstico , Colitis Ulcerosa/inmunología , Femenino , Fármacos Gastrointestinales/efectos adversos , Humanos , Irlanda , Masculino , Persona de Mediana Edad , Inducción de Remisión , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/inmunología , Adulto JovenRESUMEN
INTRODUCTION: Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD), often leading to an impaired quality of life in affected patients. Current treatment modalities include antitumour necrosis factor (anti-TNF) monoclonal antibodies (mABs) including infliximab, adalimumab and golimumab (GLM). Several recent retrospective and prospective studies have demonstrated that fixed dosing schedules of anti-TNF agents often fails to consistently achieve adequate circulating therapeutic drug levels (DL) with consequent risk of immunogenicity treatment failure and potential risk of hospitalisation and colectomy in patients with UC.The design of GLM dose Optimisation to Adequate Levels to Achieve Response in Colitis aims to address the impact of dose escalation of GLM immediately following induction and during the subsequent maintenance phase in response to suboptimal DL or persisting inflammatory burden as represented by raised faecal calprotectin (FCP). AIM: The primary aim of the study is to ascertain if monitoring of FCP and DL of GLM to guide dose optimisation (during maintenance) improves rates of patient continuous clinical response and reduces disease activity in UC. METHODS AND ANALYSIS: A randomised, multicentred two-arm trial studying the effect of dose optimisation of GLM based on FCP and DL versus treatment as per SMPC. Eligible patients will be randomised in a 1:1 ratio to 1 of 2 treatment groups and shall be treated over a period of 46 weeks. ETHICS AND DISSEMINATION: The study protocol was approved by the Research Ethics committee of St. Vincent's University Hospital. The results will be published in a peer-reviewed journal and shared with the worldwide medical community. TRIAL REGISTRATION NUMBERS: EudraCT number: 2015-004724-62; Clinicaltrials.gov Identifier: NCT0268772; Pre-results.
RESUMEN
Aberrant DNA methylation patterns have been reported in inflamed tissues and may play a role in disease. We studied DNA methylation and gene expression profiles of purified intestinal epithelial cells from ulcerative colitis patients, comparing inflamed and non-inflamed areas of the colon. We identified 577 differentially methylated sites (false discovery rate <0.2) mapping to 210 genes. From gene expression data from the same epithelial cells, we identified 62 differentially expressed genes with increased expression in the presence of inflammation at prostate cancer susceptibility genes PRAC1 and PRAC2. Four genes showed inverse correlation between methylation and gene expression; ROR1, GXYLT2, FOXA2, and, notably, RARB, a gene previously identified as a tumor suppressor in colorectal adenocarcinoma as well as breast, lung and prostate cancer. We highlight targeted and specific patterns of DNA methylation and gene expression in epithelial cells from inflamed colon, while challenging the importance of epithelial cells in the pathogenesis of chronic inflammation.
Asunto(s)
Colitis Ulcerosa/genética , Metilación de ADN , Mucosa Intestinal/metabolismo , Adulto , Colitis Ulcerosa/metabolismo , Femenino , Factor Nuclear 3-beta del Hepatocito/genética , Factor Nuclear 3-beta del Hepatocito/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Receptores Huérfanos Similares al Receptor Tirosina Quinasa/genética , Receptores Huérfanos Similares al Receptor Tirosina Quinasa/metabolismo , Receptores de Ácido Retinoico/genética , Receptores de Ácido Retinoico/metabolismo , TranscriptomaRESUMEN
BACKGROUND: Infliximab (IFX), an anti-tumour necrosis factor alpha (TNFα) monoclonal antibody, provides clinical benefits in treating Crohn's disease (CD) but its mechanisms of action are not fully elucidated. This study investigated blood monocyte repertoires and the acute effects of IFX infusion on monocyte subset phenotype and function in IFX-treated patients with CD. METHODS: Monocytes and monocyte subsets were enumerated and phenotypically characterized by multicolor flow cytometry in freshly isolated blood from healthy controls (n = 21) and patients with CD treated with (IFX, n = 24) and without (non-IFX, n = 20) IFX. For the IFX-CD group, blood was sampled immediately before (tough-IFX) and after (peak-IFX) infusion. Monocyte responses to lipopolysaccharide were analyzed by whole-blood intracellular cytokine staining. RESULTS: Non-IFX and IFX-CD patients had increased numbers of intermediate (CD14CD16) monocytes compared with healthy controls, whereas classical (CD14CD16) and nonclassical (CD14CD16) monocytes were numerically reduced in the IFX-CD group alone. In all groups, monocyte subsets expressed high surface levels of transmembrane (tm)TNFα. After IFX infusion, a significant reduction in monocyte numbers occurred. Post-IFX monocytopenia was proportionately greatest for classical and intermediate subsets, correlated with postinfusion IFX levels and was not associated with monocyte apoptosis. In contrast, lipopolysaccharide-induced production of TNFα and IL-12 by monocytes was significantly reduced in peak-IFX compared with trough-IFX blood samples. CONCLUSIONS: Actively managed CD is associated with monocyte repertoire skewing suggestive of chronic inflammatory stimulation. Infused IFX acutely targets monocytes, likely by binding to tmTNFα, resulting in a non-apoptosis-related decline in circulating monocyte numbers and blunting of the inflammatory response of monocytes remaining in the blood.
Asunto(s)
Enfermedad de Crohn/tratamiento farmacológico , Fármacos Gastrointestinales/farmacología , Infliximab/farmacología , Monocitos/efectos de los fármacos , Adulto , Anciano , Estudios de Casos y Controles , Enfermedad de Crohn/sangre , Femenino , Citometría de Flujo , Humanos , Masculino , Persona de Mediana Edad , Monocitos/citología , Adulto JovenRESUMEN
The tumour microenvironment (TME) is an important factor in determining the growth and metastasis of colorectal cancer, and can aid tumours by both establishing an immunosuppressive milieu, allowing the tumour avoid immune clearance, and by hampering the efficacy of various therapeutic regimens. The tumour microenvironment is composed of many cell types including tumour, stromal, endothelial and immune cell populations. It is widely accepted that cells present in the TME acquire distinct functional phenotypes that promote tumorigenesis. One such cell type is the mesenchymal stromal cell (MSC). Evidence suggests that MSCs exert effects in the colorectal tumour microenvironment including the promotion of angiogenesis, invasion and metastasis. MSCs immunomodulatory capacity may represent another largely unexplored central feature of MSCs tumour promoting capacity. There is considerable evidence to suggest that MSCs and their secreted factors can influence the innate and adaptive immune responses. MSC-immune cell interactions can skew the proliferation and functional activity of T-cells, dendritic cells, natural killer cells and macrophages, which could favour tumour growth and enable tumours to evade immune cell clearance. A better understanding of the interactions between the malignant cancer cell and stromal components of the TME is key to the development of more specific and efficacious therapies for colorectal cancer. Here, we review and explore MSC- mediated mechanisms of suppressing anti-tumour immune responses in the colon tumour microenvironment. Elucidation of the precise mechanism of immunomodulation exerted by tumour-educated MSCs is critical to inhibiting immunosuppression and immune evasion established by the TME, thus providing an opportunity for targeted and efficacious immunotherapy for colorectal cancer growth and metastasis.
Asunto(s)
Colon/inmunología , Neoplasias Colorrectales/inmunología , Células Madre Mesenquimatosas/inmunología , Animales , Antígenos de Neoplasias/inmunología , Humanos , Inmunidad , Terapia de Inmunosupresión , Escape del Tumor , Microambiente TumoralRESUMEN
Region and cell-type specific differences in the molecular make up of colon epithelial cells have been reported. Those differences may underlie the region-specific characteristics of common colon epithelial diseases such as colorectal cancer and inflammatory bowel disease. DNA methylation is a cell-type specific epigenetic mark, essential for transcriptional regulation, silencing of repetitive DNA and genomic imprinting. Little is known about any region-specific variations in methylation patterns in human colon epithelial cells. Using purified epithelial cells and whole biopsies (n= 19) from human subjects, we generated epigenome-wide DNA methylation data (using the HELP-tagging assay), comparing the methylation signatures of the proximal and distal colon. We identified a total of 125 differentially methylated sites (DMS) mapping to transcription start sites of protein-coding genes, most notably several members of the homeobox (HOX) family of genes. Patterns of differential methylation were validated with MassArray EpiTYPER. We also examined DNA methylation in whole biopsies, applying a computational technique to deconvolve variation in methylation within cell types and variation in cell-type composition across biopsies. Including inferred epithelial proportions as a covariate in differential methylation analysis applied to the whole biopsies resulted in greater overlap with the results obtained from purified epithelial cells compared with when the covariate was not included. Results obtained from both approaches highlight region-specific methylation patterns of HOX genes in colonic epithelium. Regional variation in methylation patterns has implications for the study of diseases that exhibit regional expression patterns in the human colon, such as inflammatory bowel disease and colorectal cancer.
Asunto(s)
Colon/citología , Metilación de ADN , Genes Homeobox , Biopsia , Colon/fisiología , Epigénesis Genética , Células Epiteliales/fisiología , Humanos , Reproducibilidad de los ResultadosRESUMEN
Tumor necrosis factor alpha (TNF-α) has been widely accepted as a therapeutic target for inflammatory disorders including inflammatory bowel disease. Anti-TNF-α monoclonal antibodies (mAbs) including infliximab, adalimumab, golimumab, and certolizumab pegol have revolutionized therapy for these chronic inflammatory disorders. These agents are potent inhibitors of TNF-α, but significant evidence points to the fact that their actions extend beyond simple neutralization of the cytokine. Recent advances in understanding the mechanism of action of anti-TNF-α mAbs has discovered a number of previously unrecognized actions that are likely to be relevant in mediating their anti-inflammatory effects. Many of those actions are mediated by the binding of the antibodies to transmembrane TNF-α (tmTNF-α) and involve complex interactions with other molecular factors and cells. In this review, we have highlighted new information on the mechanism of actions of anti-TNF-α mAbs, from in vitro and in vivo studies. Despite obvious benefits in many patients, the clinical use of these antibodies are hampered by the fact that some patients do not respond to them, and among patients who do respond, many will develop recurrent disease despite continued dosing. Although pharmacokinetic factors explain some of the observed cases of partial or complete resistance to the effects of anti-TNF-α mAbs, other nonresponder patients may be resistant to those agents mechanism of action. A more thorough understanding of the mechanism of action of anti-TNF-α mAbs may allow the development of strategies to individualize therapy and to overcome resistance.