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1.
Cell ; 152(1-2): 25-38, 2013 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-23273993

RESUMO

Cell-type plasticity within a tumor has recently been suggested to cause a bidirectional conversion between tumor-initiating stem cells and nonstem cells triggered by an inflammatory stroma. NF-κB represents a key transcription factor within the inflammatory tumor microenvironment. However, NF-κB's function in tumor-initiating cells has not been examined yet. Using a genetic model of intestinal epithelial cell (IEC)-restricted constitutive Wnt-activation, which comprises the most common event in the initiation of colon cancer, we demonstrate that NF-κB modulates Wnt signaling and show that IEC-specific ablation of RelA/p65 retards crypt stem cell expansion. In contrast, elevated NF-κB signaling enhances Wnt activation and induces dedifferentiation of nonstem cells that acquire tumor-initiating capacity. Thus, our data support the concept of bidirectional conversion and highlight the importance of inflammatory signaling for dedifferentiation and generation of tumor-initiating cells in vivo.


Assuntos
Desdiferenciação Celular , Transformação Celular Neoplásica , Neoplasias do Colo/patologia , Células-Tronco Neoplásicas/patologia , Animais , Colo/patologia , Células Epiteliais/patologia , Feminino , Humanos , Masculino , Camundongos , NF-kappa B/metabolismo , Via de Sinalização Wnt
2.
BMC Cancer ; 24(1): 234, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378472

RESUMO

BACKGROUND: Peroxisome proliferator-activated receptor gamma (PPARG) is a member of the nuclear receptor family. It is involved in the regulation of adipogenesis, lipid metabolism, insulin sensitivity, vascular homeostasis and inflammation. In addition, PPARG agonists, known as thiazolidinediones, are well established in the treatment of type 2 diabetes mellitus. PPARGs role in cancer is a matter of debate, as pro- and anti-tumour properties have been described in various tumour entities. Currently, the specific role of PPARG in patients with colorectal cancer (CRC) is not fully understood. MATERIAL AND METHODS: The prognostic impact of PPARG expression was investigated by immunohistochemistry in a case-control study using a matched pair selection of CRC tumours (n = 246) with either distant metastases to the liver (n = 82), lung (n = 82) or without distant metastases (n = 82). Its effect on proliferation as well as the sensitivity to the chemotherapeutic drug 5-fluorouracil (5-FU) was examined after activation, inhibition, and transient gene knockdown of PPARG in the CRC cell lines SW403 and HT29. RESULTS: High PPARG expression was significantly associated with pulmonary metastasis (p = 0.019). Patients without distant metastases had a significantly longer overall survival with low PPARG expression in their tumours compared to patients with high PPARG expression (p = 0.045). In the pulmonary metastasis cohort instead, a trend towards longer survival was observed for patients with high PPARG expression in their tumour (p = 0.059). Activation of PPARG by pioglitazone and rosiglitazone resulted in a significant dose-dependent increase in proliferation of CRC cell lines. Inhibition of PPARG by its specific inhibitor GW9662 and siRNA-mediated knockdown of PPARG significantly decreased proliferation. Activating PPARG significantly increased the CRC cell lines sensitivity to 5-FU while its inhibition decreased it. CONCLUSION: The prognostic effect of PPARG expression depends on the metastasis localization in advanced CRC patients. Activation of PPARG increased malignancy associated traits such as proliferation in CRC cell lines but also increases sensitivity towards the chemotherapeutic agent 5-FU. Based on this finding, a combination therapy of PPARG agonists and 5-FU-based chemotherapy constitutes a promising strategy which should be further investigated.


Assuntos
Neoplasias Colorretais , Diabetes Mellitus Tipo 2 , Humanos , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , PPAR gama/agonistas , Diabetes Mellitus Tipo 2/tratamento farmacológico , Estudos de Casos e Controles , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica
3.
Emerg Infect Dis ; 29(6): 1280-1283, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37209696

RESUMO

Microscopy of mummified visceral tissue from a Medici family member in Italy identified a potential blood vessel containing erythrocytes. Giemsa staining, atomic force microscopy, and immunohistochemistry confirmed Plasmodium falciparum inside those erythrocytes. Our results indicate an ancient Mediterranean presence of P. falciparum, which remains responsible for most malaria deaths in Africa.


Assuntos
Malária Falciparum , Malária , Humanos , Malária/epidemiologia , Malária Falciparum/epidemiologia , Plasmodium falciparum , Microscopia/métodos , Itália/epidemiologia
4.
Eur J Vasc Endovasc Surg ; 63(2): 268-274, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34872814

RESUMO

OBJECTIVE: To assess the incidence of post-operative non-ischaemic cerebral complications as a pivotal outcome parameter with respect to size of cerebral infarction, timing of surgery, and peri-operative management in patients with symptomatic carotid stenosis who underwent carotid endarterectomy (CEA). METHODS: Retrospective analysis of prospectively collected single centre CEA registry data. Consecutive patients with symptomatic carotid stenosis were subjected to standard patch endarterectomy. Brain infarct size was measured from the axial slice of pre-operative computed tomography/magnetic resonance imaging demonstrating the largest infarct dimension and was categorised as large (> 4 cm2), small (≤ 4 cm2), or absent. CEA was performed early (within 14 days) or delayed (15 - 180 days) after the ischaemic event. Peri-operative antiplatelet regimen (none, single, dual) and mean arterial blood pressure during surgery and at post-operative stroke unit monitoring were registered. Non-ischaemic post-operative cerebral complications were recorded comprising haemorrhagic stroke and encephalopathy, i.e., prolonged unconsciousness, delirium, epileptic seizure, or headache. RESULTS: 646 symptomatic patients were enrolled of whom 340 (52.6%) underwent early CEA; 367 patients (56.8%) demonstrated brain infarction corresponding to stenosis induced symptoms which was small in 266 (41.2%) and large in 101 (15.6%). Post-operative non-ischaemic cerebral complications occurred in 12 patients (1.9%; 10 encephalopathies, two haemorrhagic strokes) and were independently associated with large infarcts (adjusted odds ratio [OR] 6.839; 95% confidence interval [CI] 1.699 - 27.534) and median intra-operative mean arterial blood pressure in the upper quartile, i.e., above 120 mmHg (adjusted OR 13.318; 95% CI 2.749 - 64.519). Timing of CEA after the ischaemic event, pre-operative antiplatelet regimen, and post-operative blood pressure were not associated with non-ischaemic cerebral complications. CONCLUSION: Infarct size and unintended high peri-operative blood pressure may increase the risk of non-ischaemic complications at CEA independently of whether performed early or delayed.


Assuntos
Infarto Encefálico/epidemiologia , Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Tempo para o Tratamento/estatística & dados numéricos , Idoso , Encéfalo/diagnóstico por imagem , Infarto Encefálico/diagnóstico , Infarto Encefálico/etiologia , Infarto Encefálico/cirurgia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Razão de Chances , Assistência Perioperatória/métodos , Assistência Perioperatória/estatística & dados numéricos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Estudos Prospectivos , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Resultado do Tratamento
5.
Environ Sci Technol ; 56(17): 12014-12023, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35994629

RESUMO

Recent progress in 3D X-ray microscopy allows the analysis of coated gasoline particulate filters on a detailed pore-scale level. However, derivable detailed three-dimensional models for filter simulation are not applicable under transient driving conditions of automotive aftertreatment systems due to their inherent complexity. Here, we present a novel concept to utilize highly resolved 3D X-ray microscopy scans and their quantitative analysis for a macroscopic model of coated gasoline particulate filters intended to be applied in a driving cycle. A previously developed filtration model build on a 1D + 1D flow model on the channel scale of a filter is utilized. Accompanying measurements conducted on a dynamic engine test bench serve as validation for pressure drop and filtration characteristics. With the determined properties from 3D X-ray microscopy, the macroscopic model successfully replicates the measurements. Regarding the filter coating, the reduced porosity and a decrease of medium sized pores relative to an uncoated substrate reduce the filtration efficiency under steady-state as well as transient conditions.


Assuntos
Gasolina , Emissões de Veículos , Poeira/análise , Filtração/métodos , Microscopia , Tamanho da Partícula , Material Particulado/análise , Emissões de Veículos/análise , Raios X
6.
Future Oncol ; 18(4): 481-489, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35023359

RESUMO

Aim: To analyze immune cell populations in non-small-cell lung cancer (NSCLC) tumors and matched tumor-bearing and non-tumor-bearing lymph nodes (ntbLNs) to predict prognosis. Patients & methods: 71 patients with long-term disease-free survival and 80 patients with relapse within 3 years were included in this study. We used Cox regression to identify factors associated with overall survival (OS) and progression-free survival (PFS). Results: Sinus histiocytosis and tumor-infiltrating lymphocyte density in the tumor were positively associated with PFS and OS. CD4 expression in node 1 (hazard ratio = 0.72; p = 0.02) and node 2 (hazard ratio = 0.91; p = 0.04) ntbLNs were positively correlated with OS and PFS, respectively. Discussion: Immunological markers in ntbLNs could be used to predict survival in NSCLC.


Lay abstract Aim: We analyzed populations of immune cells in non-small-cell lung cancer (NSCLC). In addition, we also investigated lymph nodes from the same patient that contained or did not contain cancer cells. Patients & methods: We included 71 patients whose cancer did not return within 3 years and 80 patients whose cancer did return within 3 years after they underwent surgery to remove their tumors. We used various statistical methods to identify factors that can predict survival. Results: Sinus histiocytosis (a widening of ducts in the lymph nodes due to an increased number of certain cells) and the density of tumor-infiltrating lymphocytes (immune cells that enter the tumor to destroy it) can predict how long patients can survive after surgery or if their tumor will come back quickly. Discussion: Looking at immune cells can help physicians decide which patients need increased follow-up care due to an increased risk for their tumors to return.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/imunologia , Histiocitose Sinusal/imunologia , Neoplasias Pulmonares/imunologia , Linfonodos/imunologia , Linfócitos do Interstício Tumoral/imunologia , Idoso , Antígenos CD4/imunologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Pulmonares/cirurgia , Linfonodos/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Intervalo Livre de Progressão , Modelos de Riscos Proporcionais , Recidiva
7.
Glia ; 69(1): 182-200, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32865286

RESUMO

In the advanced stages of Alzheimer's disease (AD), microglia are transformed to an activated phenotype with thickened and retracted processes, migrate to the site of amyloid-beta (Aß) plaques, and proliferate. In the early stages of AD, it is still poorly understood whether the microglial function is altered and which factors may regulate these changes. Here, we focused on studying microglia in the retrosplenial cortex (RSC) in 3- to 4-month-old 5xFAD mice as a transgenic mouse model of AD. At this age, there are neither Aß plaques, nor activation of microglia, nor dysregulation in the expression of genes encoding major extracellular matrix (ECM) molecules or extracellular proteases in the RSC. Still, histochemical evaluation of the fine structure of neural ECM revealed increased levels of Wisteria floribunda agglutinin labeling in holes of perineuronal nets and changes in the perimeter of ECM barriers around the holes in 5xFAD mice. Two-photon vital microscopy demonstrated normal morphology and resting motility of microglia but strongly diminished number of microglial cells that migrated to the photolesion site in 5xFAD mice. Enzymatic digestion of ECM by chondroitinase ABC (ChABC) ameliorated this defect. Accordingly, the characterization of cell surface markers by flow cytometry demonstrated altered expression of microglial CD45. Moreover, ChABC treatment reduced the invasion of myeloid-derived mononuclear cells into the RSC of 5xFAD mice. Hence, the migration of both microglia and myeloid cells is altered during the early stages of amyloidosis and can be restored at least partially by the attenuation of the ECM.


Assuntos
Amiloidose , Doença de Alzheimer , Peptídeos beta-Amiloides , Animais , Modelos Animais de Doenças , Matriz Extracelular , Camundongos , Camundongos Transgênicos , Microglia , Placa Amiloide
8.
Int J Cancer ; 148(8): 1919-1927, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33113215

RESUMO

The aim of the study was to investigate the predictive impact of extracranial metastatic patterns on course of disease and survival in patients with colorectal cancer (CRC) and brain metastasis (BM). A total of 228 patients (134 male [59%], 94 female [41%]) with histologically proven CRC and BM were classified into different groups according to extracranial metastatic patterns. Time intervals to metastatic events and survival times from initial CRC diagnosis, extracranial and intracranial metastasis were analyzed. Extracranial organs mostly affected were liver (102 of 228 [44.7%]) and lung (96 of 228 [42.1%]). Liver and lung metastases were detected in 31 patients (13.6%). Calculated over the entire course of disease, patients with lung metastasis showed longer overall survival (OS) than patients with liver metastasis or patients without lung metastasis (43.9 vs 34.6 [P = .002] vs 35.0 months [P = .002]). From the date of initial CRC diagnosis, lung metastasis occurred later in CRC history than liver metastasis (24.3 vs 7.5 months). Once lung metastasis was diagnosed, BM occurred faster than in patients with liver metastasis (15.8 vs 26.0 months; Δ 10.2 months). Accordingly, OS from the diagnosis of liver metastasis was longer than from lung metastasis (27.1 vs 19.6 months [P = .08]). Once BM was present, patients with lung metastasis lived longer than patients with liver metastasis (3.8 vs 1.1 months [P = .028]). Shortest survival times in all survival categories analyzed revealed patients with concurrent liver and lung metastasis. Patients with CRC and BM form a heterogeneous cohort where extracranial metastasis to liver or lungs predicts survival.


Assuntos
Neoplasias Encefálicas/secundário , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Neoplasias Encefálicas/diagnóstico , Estudos de Coortes , Neoplasias Colorretais/terapia , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Masculino , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Prognóstico , Fatores de Tempo
9.
BMC Cancer ; 21(1): 1243, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34794407

RESUMO

BACKGROUND: Molecular differences in colorectal cancer (CRC) are associated with the metastatic route. Patient survival is mainly driven by metastatic spread thus it is imperative to understand its key drivers to develop biomarkers for risk stratification, follow-up protocols and personalized therapy. Thus, this study aimed to identify genes associated with the metastatic route in CRC. MATERIAL AND METHODS: CRC patients resected at our clinic from 2005 to 2014 and with a minimum 5-year follow-up were included in this analysis and grouped into CRC with hepatic (HEP), peritoneal (PER) or without distant metastases (M0), and HEP/PER. Firstly, tumor RNA of 6 patients each was isolated by microdissection from formalin-fixed paraffin-embedded specimens and analyzed by a NanoString analysis. Subsequently, these results were validated with immunohistochemistry and correlated to clinicopathological parameters in a larger collective of CRC patients (HEP n = 51, PER n = 44, M0 n = 47, HEP/PER n = 28). RESULTS: Compared to M0, HEP tumors showed 20 differentially expressed genes associated with epithelial-mesenchymal transition (EMT) and angiogenesis. Compared to M0, PER tumors had 18 differentially expressed genes. The finding of different gene signatures was supported by the multidimensional principal component clustering analysis. Tumor perforation did not influence the metastatic route. CIB1 was homogenously and significantly overexpressed in HEP compared to M0 (p < 0.001), but not in PER. Furthermore, immunohistochemical validation demonstrated that the mean CIB1 expression in HEP was 80% higher than in M0 (p < 0.001). CONCLUSION: Gene expression analysis revealed that CIB1 is significantly overexpressed in CRC leading to liver metastases compared to M0 and PER. Thus, the present results suggest that CIB1 may play a crucial role for hematogenous spread to the liver but not for peritoneal carcinomatosis. Consequently, CIB1 seems to be a promising prognostic marker and a potential tool for future targeted therapies as well as early diagnostics and follow-up.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Neoplasias do Colo/genética , Neoplasias Hepáticas/secundário , Proteínas de Neoplasias/genética , Neoplasias Peritoneais/secundário , Idoso , Neoplasias do Colo/patologia , Transição Epitelial-Mesenquimal/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Neovascularização Patológica/genética
10.
Brain Behav Immun ; 93: 322-330, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33486002

RESUMO

Flow stagnation of peri-ischemic capillaries due to dynamic leukocyte stalls has been described to be a contributor to ongoing penumbral injury in transient brain ischemia, but has not been investigated in permanent experimental stroke so far. Moreover, it is discussed that obstructing neutrophils are involved in this process; however, their contribution has not yet been proven. Here, we characterize the dynamics of neutrophil granulocytes in two models of permanent stroke (photothrombosis and permanent middle cerebral artery occlusion) using intravital two-photon fluorescence microscopy. Different to previous studies on LysM-eGFP+ cells we additionally apply a transgenic mouse model with tdTomato-expressing neutrophils to avoid interference from additional immune cell subsets. We identify repetitively occurring capillary stalls of varying duration promoted by neutrophils in both models of permanent cerebral ischemia, validating the suitability of our new transgenic mouse model in determining neutrophil occlusion formation in vivo. Flow cytometric analysis of peripheral blood (PB) and brain tissue from mice subjected to photothrombosis reveal an increase in the total proportion of neutrophils, with selective upregulation of endothelial adherence markers in the PB. In conclusion, the dynamic microcirculatory stall phenomenon that is described after transient ischemia followed by reperfusion also occurs after permanent small- or large-vessel stroke and is clearly attributable to neutrophils.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Animais , Capilares , Modelos Animais de Doenças , Granulócitos , Infarto da Artéria Cerebral Média , Camundongos , Camundongos Endogâmicos C57BL , Microcirculação , Neutrófilos
11.
BMC Neurol ; 21(1): 228, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34157987

RESUMO

BACKROUND: We describe one of the first cases of a Posterior reversible encephalopathy syndrome (PRES) under tocilizumab as treatment of Giant cell arteritis (GCA). CASE PRESENTATION: A 65-year-old female with known GCA and treatment with Tocilizumab (TCZ) developed a convulsive epileptic seizure for the first time. MRI was suggestive of PRES and an associated left sided occipital hemorrhage. Extensive high blood pressure values were not detected. The patient recovered within a week and no further seizures occurred under anticonvulsive medication. CONCLUSION: PRES during the treatment with Tocilizumab hasn't been described in GCA so far. There are single reports of an association between TCZ and PRES in other entities. Thus, a link between interleukin-6 and the integrity of the vasculature could be considered. The clinical consequence should be a stringent blood pressure monitoring in the ambulant setting of patients receiving TCZ.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Arterite de Células Gigantes/tratamento farmacológico , Síndrome da Leucoencefalopatia Posterior/diagnóstico , Idoso , Anticorpos Monoclonais Humanizados/uso terapêutico , Feminino , Arterite de Células Gigantes/patologia , Hemorragia/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Síndrome da Leucoencefalopatia Posterior/diagnóstico por imagem , Síndrome da Leucoencefalopatia Posterior/etiologia
12.
Z Gastroenterol ; 59(1): 50-55, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33429450

RESUMO

Infections caused by pathogens of the Mycobacterium tuberculosis complex, i. e., tuberculosis (TB), and the non-infectious, autoimmune disease sarcoidosis are among the most common granulomatous diseases worldwide. Typically, the lung is the primary site of infection and manifestation, respectively which makes the two diseases important differential diagnoses. Both diseases can affect virtually all organ systems, albeit with significantly lower incidence. CASE PRESENTATION: We report the case of a 50-year-old Indian man presenting with a tuberculous perihepatic abscess and a systemic inflammatory response after being diagnosed with neurosarcoidosis presenting as a single granuloma in the frontal lobe with lymphadenopathy in 2014. On day of admission the patient presented with right upper abdominal pain and fever for two weeks. With increased inflammatory parameters in serum and after finding of external CT images, a perihepatic abscess was suspected. This encapsulated cave was drained percutaneously under CT control. A high concentration of acid-fast rods was detected using ZN, PCR was positive for M. tuberculosis. Several samples of sputum and urine were microscopically negative but yielded growth of Mycobacteria after four weeks. DISCUSSION: This is a case presenting with two different granulomatous diseases, each of which manifested itself in an atypical form. The tuberculous liver abscess might either be explained as a flare-up of latent tuberculosis under azathioprine therapy or as a reinfection acquired during one of several visits in the high-prevalence country India. In addition, it must be discussed whether the cerebral granuloma in 2014 could have been an early stage of tuberculous granuloma. Sensitivity of ZN staining is significantly reduced in cerebral samples, and negative PCR-results might be due to low germ load or methodical issues, e. g., decreased sensitivity in formalin fixated samples.


Assuntos
Doenças do Sistema Nervoso Central/diagnóstico , Mycobacterium tuberculosis/isolamento & purificação , Sarcoidose/diagnóstico , Tuberculose/diagnóstico , Dor Abdominal/etiologia , Drenagem , Febre/etiologia , Granuloma/diagnóstico , Humanos , Abscesso Hepático/microbiologia , Abscesso Hepático/cirurgia , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase , Resultado do Tratamento , Tuberculose/tratamento farmacológico
13.
Pathologe ; 42(Suppl 1): 98-109, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34259881

RESUMO

In the past 25 years, treatment of metastatic colorectal cancer (mCRC) has undergone profound changes. The approval of newer chemotherapeutics such as irinotecan and oxaliplatin was followed in 2005 by the first targeted therapies, for example, monoclonal antibodies directed against the epidermal growth factor receptor (EGFR), as cetuximab and panitumumab, or the angiogenesis inhibitors bevacizumab, ramucirumab, and aflibercept. With the rapidly progressing molecular characterization of mCRC in the last 10 years and the classification of the disease in four consensus subtypes, further changes are emerging, which will promote, among other things, the introduction of protein-kinase inhibitors developed for specific molecular aberrations as well as immune checkpoint inhibitors into the treatment algorithm.Thorough molecular pathologic testing is indispensable today for guideline-compliant treatment of mCRC patients. In addition to RAS testing as a precondition for the therapy decision with regard to cetuximab and panitumumab, BRAF testing is of considerable relevance to allow decision making with regard to the newly approved chemotherapy-free combination of the BRAF inhibitor encorafenib and cetuximab in cases where a BRAF-V600E mutation is detected. Additional diagnostic tests should also include genome instability (microsatellite instability). Overall, more and more molecular alterations need to be investigated simultaneously, so that the use of focused next-generation sequencing is increasingly recommended.This overview describes the prognostic relevance of BRAF testing in the context of molecular pathologic diagnostics of mCRC, presents new treatment options for BRAF-mutated mCRC patients, and explains which modern DNA analytical and immunohistochemical methods are available to detect BRAF mutations in mCRC patients.


Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas B-raf , Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cetuximab/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Humanos , Mutação , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)
14.
Pathologe ; 42(6): 578-590, 2021 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-33956173

RESUMO

In the past 25 years, treatment of metastatic colorectal cancer (mCRC) has undergone profound changes. The approval of newer chemotherapeutics such as irinotecan and oxaliplatin was followed in 2005 by the first targeted therapies, for example, monoclonal antibodies directed against the epidermal growth factor receptor (EGFR), as cetuximab and panitumumab, or the angiogenesis inhibitors bevacizumab, ramucirumab, and aflibercept. With the rapidly progressing molecular characterization of mCRC in the last 10 years and the classification of the disease in four consensus subtypes, further changes are emerging, which will promote, among other things, the introduction of protein-kinase inhibitors developed for specific molecular aberrations as well as immune checkpoint inhibitors into the treatment algorithm.Thorough molecular pathologic testing is indispensable today for guideline-compliant treatment of mCRC patients. In addition to RAS testing as a precondition for the therapy decision with regard to cetuximab and panitumumab, BRAF testing is of considerable relevance to allow decision making with regard to the newly approved chemotherapy-free combination of the BRAF inhibitor encorafenib and cetuximab in cases where a BRAF-V600E mutation is detected. Additional diagnostic tests should also include genome instability (microsatellite instability). Overall, more and more molecular alterations need to be investigated simultaneously, so that the use of focused next-generation sequencing is increasingly recommended.This overview describes the prognostic relevance of BRAF testing in the context of molecular pathologic diagnostics of mCRC, presents new treatment options for BRAF-mutated mCRC patients, and explains which modern DNA analytical and immunohistochemical methods are available to detect BRAF mutations in mCRC patients.


Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas B-raf , Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cetuximab/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Humanos , Mutação , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)
15.
Cell Commun Signal ; 18(1): 102, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32586342

RESUMO

BACKGROUND: Wnt signaling drives epithelial self-renewal and disease progression in human colonic epithelium and colorectal cancer (CRC). Characterization of Wnt effector pathways is key for our understanding of these processes and for developing therapeutic strategies that aim to preserve tissue homeostasis. O-glycosylated cell surface proteins, such as α-dystroglycan (α-DG), mediate cellular adhesion to extracellular matrix components. We revealed a Wnt/LARGE2/α-DG signaling pathway which triggers this mode of colonic epithelial cell-to-matrix interaction in health and disease. METHODS: Next generation sequencing upon shRNA-mediated silencing of adenomatous polyposis coli (APC), and quantitative chromatin immunoprecipitation (qChIP) combined with CRISPR/Cas9-mediated transcription factor binding site targeting characterized LARGE2 as a Wnt target gene. Quantitative mass spectrometry analysis on size-fractionated, glycoprotein-enriched samples revealed functional O-glycosylation of α-DG by LARGE2 in CRC. The biology of Wnt/LARGE2/α-DG signaling was assessed by affinity-based glycoprotein enrichment, laminin overlay, CRC-to-endothelial cell adhesion, and transwell migration assays. Experiments on primary tissue, human colonic (tumor) organoids, and bioinformatic analysis of CRC cohort data confirmed the biological relevance of our findings. RESULTS: Next generation sequencing identified the LARGE2 O-glycosyltransferase encoding gene as differentially expressed upon Wnt activation in CRC. Silencing of APC, conditional expression of oncogenic ß-catenin and endogenous ß-catenin-sequestration affected LARGE2 expression. The first intron of LARGE2 contained a CTTTGATC motif essential for Wnt-driven LARGE2 expression, showed occupation by the Wnt transcription factor TCF7L2, and Wnt activation triggered LARGE2-dependent α-DG O-glycosylation and laminin-adhesion in CRC cells. Colonic crypts and organoids expressed LARGE2 mainly in stem cell-enriched subpopulations. In human adenoma organoids, activity of the LARGE2/α-DG axis was Wnt-dose dependent. LARGE2 expression was elevated in CRC and correlated with the Wnt-driven molecular subtype and intestinal stem cell features. O-glycosylated α-DG represented a Wnt/LARGE2-dependent feature in CRC cell lines and patient-derived tumor organoids. Modulation of LARGE2/α-DG signaling affected CRC cell migration through laminin-coated membranes and adhesion to endothelial cells. CONCLUSIONS: We conclude that the LARGE2 O-glycosyltransferase-encoding gene represents a direct target of canonical Wnt signaling and mediates functional O-glycosylation of α-dystroglycan (α-DG) in human colonic stem/progenitor cells and Wnt-driven CRC. Our work implies that aberrant Wnt activation augments CRC cell-matrix adhesion by increasing LARGE/α-DG-mediated laminin-adhesiveness. Video abstract.


Assuntos
Colo/patologia , Neoplasias Colorretais/metabolismo , Células Epiteliais/metabolismo , Glicosiltransferases/metabolismo , Laminina/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Wnt/metabolismo , Adenoma/patologia , Proteína da Polipose Adenomatosa do Colo/metabolismo , Animais , Sequência de Bases , Adesão Celular , Diferenciação Celular , Movimento Celular , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Distroglicanas/metabolismo , Células Endoteliais/metabolismo , Epitélio/metabolismo , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Glicosilação , Glicosiltransferases/genética , Células HT29 , Humanos , Intestino Delgado/metabolismo , Neoplasias Hepáticas/secundário , Proteínas de Membrana/genética , Camundongos , Organoides/metabolismo , Organoides/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Via de Sinalização Wnt
16.
Cerebrovasc Dis ; 49(4): 412-418, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756054

RESUMO

INTRODUCTION: Approximately 1 out of 4 stroke patients suffers ischemic stroke secondary to atrial fibrillation (AF). Although indicated, withholding of anticoagulants for secondary prevention is a widespread phenomenon. OBJECTIVE: We examined the longitudinal change of recommendation and prescription of secondary preventive anticoagulation in AF patients in an acute stroke center setting focusing on the impact of the introduction of direct oral anticoagulants (DOACs) and the change of national stroke prevention guidelines. METHODS: Consecutive patients admitted with an acute cerebrovascular ischemic event underwent regular diagnostic work-up. Pseudonymized clinical data were entered into the institution's stroke registry. In those patients with AF, discharge letters were collected and evaluated for temporal trends and affecting factors of recommended and prescribed antithrombotic secondary medication at the time of discharge from hospital. RESULTS: Of 7,175 patients admitted between January 2009 and December 2018, 1,812 (25.3%) suffered stroke caused by AF. Frequency of patients with recommended anticoagulation increased within the observation period from 66.7 to 95.8% (per year; adjusted odds ratio [OR], 1.309; confidence interval [CI], 1.153-1.486). Independently from this time trend, DOAC approval (adjusted OR, 4.026; CI 1.962-8.265) and guideline change (adjusted OR, 2.184; CI, 1.006-4.743) were associated with an increasing frequency of recommendation for anticoagulation. The rate of patients already receiving recommended anticoagulation for secondary prevention at discharge increased from 42.1 to 62.5%. Introduction of DOACs was not associated with this trend, and guideline change was even associated with decreasing frequency of anticoagulated patients at hospital discharge (adjusted OR, 0.641; CI, 0.414-0.991). Fear of early intracerebral bleeding was the most common reason for withholding anticoagulation (37%) at hospital discharge and stayed stable during the observation period. CONCLUSIONS: Changing national guidelines with discard of contraindications for anticoagulation and the introduction of DOACs led to a broader recommendation of oral anticoagulation. However, both, new guidelines and DOACs, were not found to be associated with an increasing percentage of patients discharged from our hospital already on recommended anticoagulant prevention. This might be explained by the decreasing length of hospital stay during the study period and a missing evidence of early bleeding risk of DOACs in patients with acute brain infarction. Evidence-based data to close this therapeutic gap are needed.


Assuntos
Fibrilação Atrial/tratamento farmacológico , Inibidores do Fator Xa/administração & dosagem , Pacientes Internados , Guias de Prática Clínica como Assunto/normas , Padrões de Prática Médica/normas , Prevenção Secundária/normas , Acidente Vascular Cerebral/prevenção & controle , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Prescrições de Medicamentos , Inibidores do Fator Xa/efeitos adversos , Feminino , Humanos , Hemorragias Intracranianas/induzido quimicamente , Tempo de Internação/tendências , Masculino , Alta do Paciente/tendências , Sistema de Registros , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Fatores de Tempo , Resultado do Tratamento , Estados Unidos/epidemiologia
17.
J Vasc Interv Radiol ; 31(12): 2132-2140.e5, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33160828

RESUMO

PURPOSE: To evaluate feasibility, embolization success, biodegradability, reperfusion, and biocompatibility of biodegradable microspheres (MS) made from polydioxanone (PDO) for transcatheter arterial embolization. MATERIALS AND METHODS: Unilateral selective renal embolization of a segmental artery was performed in 16 New Zealand White rabbits with PDO-MS (100-150 µm and 90-315 µm). Animals were randomly assigned to different observation periods and underwent control digital subtraction angiography (DSA) and MR imaging immediately (n = 3), 1 week (n = 2), 4 weeks (n = 2), 8 weeks (n = 2), 12 weeks (n = 5), and 16 weeks (n = 2) after embolization. Kidneys were harvested for macroscopic and histologic analysis of embolization success, biodegradability, and biocompatibility. RESULTS: Embolization was technically successful in 15 of 16 animals. One animal died of anesthesia-related circulatory failure. The 100-150 µm MS were injected easily through 3-F catheters; the 90-315 µm MS tended to clog with intermittent catheter obstruction. DSA and MR imaging showed successful target embolization in 13 of 15 animals. In 2 animals, the entire kidney was affected owing to catheter clogging, including a reflux of MS while flushing. Control DSA and MR imaging showed increasing vascular reperfusion with time. Macroscopic and histologic analysis revealed necrosis/infarction in areas in which embolization was achieved. MS were extensively degraded after 16 weeks, and overall inflammatory reaction was mild. CONCLUSIONS: Biodegradable PDO-MS induced effective embolization of target vessels while demonstrating good biocompatibility. MS increasingly dissolved at 16 weeks, partial reperfusion started at week 1, and complete reperfusion started at week 8, thus offering possible advantages as a temporary embolic agent.


Assuntos
Embolização Terapêutica , Rim/patologia , Polidioxanona/administração & dosagem , Artéria Renal , Animais , Estudos de Viabilidade , Injeções Intra-Arteriais , Rim/diagnóstico por imagem , Microesferas , Necrose , Estudo de Prova de Conceito , Coelhos , Artéria Renal/diagnóstico por imagem , Fatores de Tempo
18.
Environ Sci Technol ; 54(15): 9285-9294, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32598146

RESUMO

In order to reliably predict the particle number filtration of gasoline particulate filters (GPF) under practical driving conditions, an extension to established filtration models is developed. For the validation of this approach and in order to close a gap of available measurement data at high space velocity in the literature, the particle-size-resolved fresh filtration efficiency of seven different cordierite filters is determined experimentally. Moreover, the experiments on a dynamic engine test bench focus on the impact of the pore-size distribution and the filter wall thickness under steady-state as well as transient, cold-start conditions. In order to model all trends observed, a new correlation for the particle collection due to inertial deposition is proposed and embedded in a heterogeneous multiscale model framework for a GPF. The presented approach can predict all trends observed in the measurements, including a stabilization of the filtration efficiency with increasing space velocities above a certain level. A comparison of several modeling approaches reveals the partly different behaviors at varying space velocities for the here presented model as well as for established filtration models.


Assuntos
Condução de Veículo , Gasolina , Poeira , Filtração , Gasolina/análise , Tamanho da Partícula , Material Particulado/análise , Emissões de Veículos/análise
19.
Int J Hyperthermia ; 37(1): 55-65, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31918587

RESUMO

Introduction: An abscopal effect is a clinical observation whereby a local treatment is associated with regression of metastatic cancer at a site distant from the primary location of treatment. Here, we describe the clinical systemic effect induced by regional hyperthermia combined with low-dose chemotherapy and provide immunologic correlates.Case presentation: A 15-year-old patient had been diagnosed with alveolar rhabdomyosarcoma (ARMS). All previous treatment options failed in the patient including haploidentical stem cell transplantation and donor lymphocyte infusion. The patient presented with local and metastatic disease, and upon admission, underwent regional hyperthermia combined with low-dose chemotherapy. Immediately following therapy severe skin reactions were observed. Skin biopsies revealed an intraepithelial lymphocytic infiltration dominated by CD3+/CD8+ T cells with a regular network of dendritic cells. Clinical images compared before and during sequential treatment cycles showed complete metabolic response of the local tumor for more than 10 months of therapy. In addition, metastases completely regressed although they were not direct targets of regional hyperthermia. The systemic effect was associated with enhanced frequency of NK cells and T cells expressing the lectin-like natural-killer group 2 D activating receptor (NKG2D), an increase of the CD56bright subset of NK cells, as well as an increase of effector/memory and effector CD8+ and CD4+ T cells in the blood while the percentage of CD25+FOXP3+ regulatory T cells declined.Conclusions: Regional hyperthermia combined with low-dose chemotherapy had the potential to create a systemic effect which was associated with activation of NK cells and T cells.


Assuntos
Rabdomiossarcoma/tratamento farmacológico , Rabdomiossarcoma/radioterapia , Adolescente , Feminino , Humanos , Hipertermia Induzida/métodos
20.
Vasa ; 49(1): 31-38, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31621550

RESUMO

Background: To assess the vascular and clinical course of acute symptomatic extracranial internal carotid artery (ICA) occlusion. Patients and methods: Patients with an acute ischemic event in the anterior circulation and corresponding extracranial ICA occlusion at CT angiography and/or color-coded duplex sonography underwent recurrent duplex follow-up for detection of spontaneous recanalization. Stroke recurrence and functional outcome 4.5 months after the ischemic index event assessed by modified Rankin scale served as secondary outcome parameters. Results: 133 patients (91 men, mean age 62.3 years, SD 10.8) demonstrated symptomatic occlusion of the extracranial ICA with open intracranial ICA and open middle cerebral artery and were followed-up for spontaneous recanalization. Twenty-eight recanalized spontaneously, 25 to high-grade focal stenosis within 12 days, revealing an early cumulative recanalization rate of 23 %. Detection of recanalization was independently associated with de novo dual anti-platelet therapy (adjusted odds ratio [OR], 3.24; 95 % confidence interval [CI], 1.34 to 7.80). Ischemic recurrence occurred in 16 patients, of which 10 deemed to be embolic and 5 hemodynamic. Spontaneous ICA recanalization and an exhausted cerebrovascular reserve in the hemisphere distal to the occluded ICA were both independently associated with the occurrence of a recurrent ischemic event at Cox regression. An increasing NIHSS score at admission, a decreasing middle cerebral artery flow velocity and an ischemic recurrence independently predicted poor outcome (modified Rankin scale 3 to 6) in multivariate analysis. Conclusions: Acute symptomatic extracranial ICA occlusion is an unstable condition with frequent spontaneous recanalization to severe stenosis and early embolic stroke recurrence, demanding appropriate prevention especially in those patients with only mild deficit.


Assuntos
Doenças das Artérias Carótidas , Estenose das Carótidas , Embolia , Acidente Vascular Cerebral , Idoso , Artéria Carótida Interna , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
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