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1.
Cancer Res Commun ; 3(8): 1501-1513, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37565053

RESUMO

Tumor-specific MHC class II (tsMHC-II) expression impacts tumor microenvironmental immunity. tsMHC-II positive cancer cells may act as surrogate antigen-presenting cells and targets for CD4+ T cell-mediated lysis. In colorectal cancer, tsMHC-II negativity is common, in cell lines due to CIITA promoter methylation. To clarify mechanisms of tsMHC-II repression in colorectal cancer, we analyzed colorectal cancer organoids which are epigenetically faithful to tissue of origin. 15 primary colorectal cancer organoids were treated with IFNγ ± epigenetic modifiers: flow cytometry was used for tsMHC-II expression. qRT-PCR, total RNA sequencing, nanopore sequencing, bisulfite conversion/pyrosequencing, and Western blotting was used to quantitate CIITA, STAT1, IRF1, and JAK1 expression, mutations and promoter methylation and chromatin immunoprecipitation to quantitate H3K9ac, H3K9Me2, and EZH2 occupancy at CIITA. We define three types of response to IFNγ in colorectal cancer: strong, weak, and noninducibility. Delayed and restricted expression even with prolonged IFNγ exposure was due to IFNγ-mediated EZH2 occupancy at CIITA. tsMHC-II expression was enhanced by EZH2 and histone deacetylase inhibition in the weakly inducible organoids. Noninducibility is seen in three consensus molecular subtype 1 (CMS1) organoids due to JAK1 mutation. No organoid demonstrates CIITA promoter methylation. Providing IFNγ signaling is intact, most colorectal cancer organoids are class II inducible. Upregulation of tsMHC-II through targeted epigenetic therapy is seen in one of fifteen organoids. Our approach can serve as a blueprint for investigating the heterogeneity of specific epigenetic mechanisms of immune suppression across individual patients in other cancers and how these might be targeted to inform the conduct of future trials of epigenetic therapies as immune adjuvants more strategically in cancer. Significance: Cancer cell expression of MHC class II significantly impacts tumor microenvironmental immunity. Previous studies investigating mechanisms of repression of IFNγ-inducible class II expression using cell lines demonstrate epigenetic silencing of IFN pathway genes as a frequent immune evasion strategy. Unlike cell lines, patient-derived organoids maintain epigenetic fidelity to tissue of origin. In the first such study, we analyze patterns, dynamics, and epigenetic control of IFNγ-induced class II expression in a series of colorectal cancer organoids.


Assuntos
Neoplasias Colorretais , Genes MHC da Classe II , Humanos , Interferon gama/farmacologia , Metilação , Linhagem Celular , Neoplasias Colorretais/genética
2.
Cochrane Database Syst Rev ; 10: CD000553, 2020 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-33089892

RESUMO

BACKGROUND: People with liver cirrhosis who have had one episode of variceal bleeding are at risk for repeated episodes of bleeding. Endoscopic intervention and portosystemic shunts are used to prevent further bleeding, but there is no consensus as to which approach is preferable. OBJECTIVES: To compare the benefits and harms of shunts (surgical shunts (total shunt (TS), distal splenorenal shunt (DSRS), or transjugular intrahepatic portosystemic shunt (TIPS)) versus endoscopic intervention (endoscopic sclerotherapy or banding, or both) with or without medical treatment (non-selective beta blockers or nitrates, or both) for prevention of variceal rebleeding in people with liver cirrhosis. SEARCH METHODS: We searched the CHBG Controlled Trials Register; CENTRAL, in the Cochrane Library; MEDLINE Ovid; Embase Ovid; LILACS (Bireme); Science Citation Index - Expanded (Web of Science); and Conference Proceedings Citation Index - Science (Web of Science); as well as conference proceedings and the references of trials identified until 22 June 2020. We contacted study investigators and industry researchers. SELECTION CRITERIA: Randomised clinical trials comparing shunts versus endoscopic interventions with or without medical treatment in people with cirrhosis who had recovered from a variceal haemorrhage. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. When possible, we collected data to allow intention-to-treat analysis. For each outcome, we estimated a meta-analysed estimate of treatment effect across trials (risk ratio for binary outcomes). We used random-effects model meta-analysis as our main analysis and as a means of presenting results. We reported differences in means for continuous outcomes without a meta-analytic estimate due to high variability in their assessment among all trials. We assessed the certainty of evidence using GRADE. MAIN RESULTS: We identified 27 randomised trials with 1828 participants. Three trials assessed TSs, five assessed DSRSs, and 19 trials assessed TIPSs. The endoscopic intervention was sclerotherapy in 16 trials, band ligation in eight trials, and a combination of band ligation and either sclerotherapy or glue injection in three trials. In eight trials, endoscopy was combined with beta blockers (in one trial plus isosorbide mononitrate). We judged all trials to be at high risk of bias. We assessed the certainty of evidence for all the outcome review results as very low (i.e. the true effects of the results are likely to be substantially different from the results of estimated effects). The very low evidence grading is due to the overall high risk of bias for all trials, and to imprecision and publication bias for some outcomes. Therefore, we are very uncertain whether portosystemic shunts versus endoscopy interventions with or without medical treatment have effects on all-cause mortality (RR 0.99, 95% CI 0.86 to 1.13; 1828 participants; 27 trials), on rebleeding (RR 0.40, 95% CI 0.33 to 0.50; 1769 participants; 26 trials), on mortality due to rebleeding (RR 0.51, 95% CI 0.34 to 0.76; 1779 participants; 26 trials), and on occurrence of hepatic encephalopathy, both acute (RR 1.60, 95% CI 1.33 to 1.92; 1649 participants; 24 trials) and chronic (RR 2.51, 95% CI 1.38 to 4.55; 956 participants; 13 trials). No data were available regarding health-related quality of life. Analysing each modality of portosystemic shunts individually (i.e. TS, DSRS, and TIPS) versus endoscopic interventions with or without medical treatment, we are very uncertain if each type of shunt has effect on all-cause mortality: TS, RR 0.46, 95% CI 0.19 to 1.13; 164 participants; 3 trials; DSRS, RR 0.93, 95% CI 0.65 to 1.33; 352 participants; 4 trials; and TIPS, RR 1.10, 95% CI 0.92 to 1.31; 1312 participants; 19 trial; on rebleeding: TS, RR 0.28, 95% CI 0.14 to 0.56; 127 participants; 2 trials; DSRS, RR 0.26, 95% CI 0.11 to 0.65; 330 participants; 5 trials; and TIPS, RR 0.44, 95% CI 0.36 to 0.55; 1312 participants; 19 trials; on mortality due to rebleeding: TS, RR 0.25, 95% CI 0.06 to 0.96; 164 participants; 3 trials; DSRS, RR 0.31, 95% CI 0.13 to 0.74; 352 participants; 5 trials; and TIPS, RR 0.65, 95% CI 0.40 to 1.04; 1263 participants; 18 trials; on acute hepatic encephalopathy: TS, RR 1.66, 95% CI 0.70 to 3.92; 115 participants; 2 trials; DSRS, RR 1.70, 95% CI 0.94 to 3.08; 287 participants; 4 trials, TIPS, RR 1.61, 95% CI 1.29 to 1.99; 1247 participants; 18 trials; and chronic hepatic encephalopathy: TS, Fisher's exact test P = 0.11; 69 participants; 1 trial; DSRS, RR 4.87, 95% CI 1.46 to 16.23; 170 participants; 2 trials; and TIPS, RR 1.88, 95% CI 0.93 to 3.80; 717 participants; 10 trials. The proportion of participants with shunt occlusion or dysfunction was overall 37% (95% CI 33% to 40%). It was 3% (95% CI 0.8% to 10%) following TS, 7% (95% CI 3% to 13%) following DSRS, and 47.1% (95% CI 43% to 51%) following TIPS. Shunt dysfunction in trials utilising polytetrafluoroethylene-covered stents was 17% (95% CI 11% to 24%). Length of inpatient hospital stay and cost were not comparable across trials. Funding was unclear in 16 trials; 11 trials were funded by government, local hospitals, or universities. AUTHORS' CONCLUSIONS: Evidence on whether portosystemic shunts versus endoscopy interventions with or without medical treatment in people with cirrhosis and previous hypertensive portal bleeding have little or no effect on all-cause mortality is very uncertain. Evidence on whether portosystemic shunts may reduce bleeding and mortality due to bleeding while increasing hepatic encephalopathy is also very uncertain. We need properly conducted trials to assess effects of these interventions not only on assessed outcomes, but also on quality of life, costs, and length of hospital stay.


Assuntos
Endoscopia/métodos , Varizes Esofágicas e Gástricas/terapia , Hemorragia Gastrointestinal/terapia , Cirrose Hepática/complicações , Derivação Portossistêmica Cirúrgica/métodos , Viés , Causas de Morte , Varizes Esofágicas e Gástricas/prevenção & controle , Hemorragia Gastrointestinal/epidemiologia , Hemorragia Gastrointestinal/prevenção & controle , Encefalopatia Hepática/epidemiologia , Encefalopatia Hepática/etiologia , Humanos , Análise de Intenção de Tratamento , Derivação Portossistêmica Cirúrgica/efeitos adversos , Derivação Portossistêmica Transjugular Intra-Hepática/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Prevenção Secundária , Derivação Esplenorrenal Cirúrgica/efeitos adversos
3.
Nutr Cancer ; 70(5): 748-754, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29781720

RESUMO

Vitamin D (vit-D) deficiency is highly prevalent in patients with gastro-entero-pancreatic neuroendocrine tumors (GEP-NET) and has been linked to reduced overall survival. We here assessed the vit-D status in 183 patients with GEP-NET at the time of their first presentation in the ARDEN NET Centre. We further examined the effect of simple advice to increase vit-D intake using over-the-counter vit-D preparations [colecalciferol (Vit-D3), 1,000-2,000 units/day], over a prospective observation period of 24 mo. At baseline, only 33.3% of patients showed vit-D sufficiency (25-OH-vit-D; >50 nmol/L), the remainder was insufficient (31.3%; 25-OH-vit-D; 25-50 nmol/L) or deficient (35.5%; 25-OH-vit-D; <25 nmol/L). Repeated advice to increase vit-D intake at routine 6-monthly follow-up appointments was associated with increased 25-OH-vit-D from 37.8 ± 3.5 nmol/L at baseline to 60.4 ± 5.6 nmol/L (P < 0.0001) and 56.8 ± 7.0 nmol/L (P = 0.039) after 12 and 24 mo. Percentage of vit-D insufficiency decreased from 66.6% at baseline to 44.9% and 46.2% after 12 and 24 months, respectively. Previous abdominal surgery, but not treatment with somatostatin analogues predicted 25-OH-vit-D levels in bootstrapped linear regression analyses (P = 0.037). In summary, simple advice to increase vit-D intake using over-the-counter preparations was associated with significant improvement of vit-D deficiency/insufficiency, although, 15% of GEP-NET patients remained deficient and may benefit from additional measures of vit-D replacement.


Assuntos
Neoplasias Gastrointestinais/complicações , Tumores Neuroendócrinos/complicações , Deficiência de Vitamina D/tratamento farmacológico , Vitamina D/uso terapêutico , Colecalciferol/uso terapêutico , Cromogranina A/sangue , Feminino , Neoplasias Gastrointestinais/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/patologia , Medicamentos sem Prescrição/uso terapêutico , Estudos Prospectivos , Análise de Regressão , Vitamina D/sangue , Deficiência de Vitamina D/etiologia
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