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1.
Cell ; 152(1-2): 25-38, 2013 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-23273993

RESUMEN

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.


Asunto(s)
Desdiferenciación Celular , Transformación Celular Neoplásica , Neoplasias del Colon/patología , Células Madre Neoplásicas/patología , Animales , Colon/patología , Células Epiteliales/patología , Femenino , Humanos , Masculino , Ratones , FN-kappa B/metabolismo , Vía de Señalización Wnt
2.
J Infect Dis ; 227(2): 206-210, 2023 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-35921542

RESUMEN

BACKGROUND: The aim of this randomized, controlled trial is to determine whether antisevere acute respiratory syndrome coronavirus 2 hyperimmune globulin (COVIG) protects against severe coronavirus disease 2019 (COVID-19) in severely immunocompromised, hospitalized, COVID-19 patients. METHODS: Patients were randomly assigned to receive COVIG or intravenous immunoglobulin (IVIG) without SARS-CoV-2 antibodies. RESULTS: Severe COVID-19 was observed in 2 of 10 (20%) patients treated with COVIG compared to 7 of 8 (88%) in the IVIG control group (P = .015, Fisher's exact test). CONCLUSIONS: Antisevere acute respiratory syndrome coronavirus 2 hyperimmune globulin may be a valuable treatment in severely immunocompromised, hospitalized, COVID-19 patients and should be considered when no monoclonal antibody therapies are available.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Inmunoglobulinas Intravenosas/uso terapéutico , Resultado del Tratamiento , Sueroterapia para COVID-19 , Inmunización Pasiva/efectos adversos
3.
Proc Natl Acad Sci U S A ; 117(41): 25560-25570, 2020 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-32989144

RESUMEN

Deregulated global mRNA translation is an emerging feature of cancer cells. Oncogenic transformation in colorectal cancer (CRC) is driven by mutations in APC, KRAS, SMAD4, and TP53, known as the adenoma-carcinoma sequence (ACS). Here we introduce each of these driver mutations into intestinal organoids to show that they are modulators of global translational capacity in intestinal epithelial cells. Increased global translation resulting from loss of Apc expression was potentiated by the presence of oncogenic KrasG12D Knockdown of Smad4 further enhanced global translation efficiency and was associated with a lower 4E-BP1-to-eIF4E ratio. Quadruple mutant cells with additional P53 loss displayed the highest global translational capacity, paralleled by high proliferation and growth rates, indicating that the proteome is heavily geared toward cell division. Transcriptional reprogramming facilitating global translation included elevated ribogenesis and activation of mTORC1 signaling. Accordingly, interfering with the mTORC1/4E-BP/eIF4E axis inhibited the growth potential endowed by accumulation of multiple drivers. In conclusion, the ACS is characterized by a strongly altered global translational landscape in epithelial cells, exposing a therapeutic potential for direct targeting of the translational apparatus.


Asunto(s)
Adenoma/genética , Carcinoma/genética , Mutación/ética , Biosíntesis de Proteínas/genética , Adenoma/metabolismo , Animales , Carcinoma/metabolismo , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Células HEK293 , Humanos , Intestinos/citología , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Ratones , Ratones Transgénicos , Organoides/metabolismo , Transducción de Señal , Técnicas de Cultivo de Tejidos
4.
Clin Infect Dis ; 75(6): 1046-1053, 2022 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-35195716

RESUMEN

BACKGROUND: Patients with hematological cancers (HC) are at high risk of infections, in particular community-acquired pneumonia (CAP). Recent data on incidence and predictors of CAP among patients with HC are scarce. METHODS: We performed a cohort study (2016-2019) in 2 hospitals in the Netherlands among adults with HC to calculate incidence rates (IRs) of CAP. In addition, we performed a nested case-control study to identify predictors of CAP. RESULTS: We identified 275 CAP cases during 6264 patient-years of follow-up. The IR of CAP was 4390/100 000 patient-years of follow-up. Compared with the general population, IR ratios ranged from 5.4 to 55.3 for the different HCs. The case fatality and intensive care unit (ICU) admission rates were 5.5% and 9.8%, respectively. Predictors for CAP in patients with HC were male sex, anemia, lymphocytopenia, chronic kidney disease, cardiovascular disease, autologous and allogeneic stem cell transplantation, treatment with immunosuppressive medication for graft-vs-host disease, treatment with rituximab in the past year, and treatment with immunomodulators (lenalidomide, thalidomide, pomalidomide and/or methotrexate) in the past month. Independent predictors of a severe disease course (death or ICU admission) included neutropenia (odds ratio, 4.14 [95% confidence interval, 1.63-10.2]), pneumococcal pneumonia (10.24 [3.48-30.1]), chronic obstructive pulmonary disease (6.90 [2.07-23.0]), and the use of antibacterial prophylaxis (2.53 [1.05-6.08]). CONCLUSIONS: The burden of CAP in patients with HC is high, with significant morbidity and mortality rates. Therefore, vaccination against respiratory pathogens early in the disease course is recommended, in particular before starting certain immunosuppressive therapies.


Asunto(s)
Infecciones Comunitarias Adquiridas , Neoplasias Hematológicas , Neumonía Neumocócica , Neumonía , Adulto , Antibacterianos , Estudios de Casos y Controles , Estudios de Cohortes , Infecciones Comunitarias Adquiridas/epidemiología , Progresión de la Enfermedad , Femenino , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/epidemiología , Hospitalización , Humanos , Incidencia , Lenalidomida , Masculino , Metotrexato , Neumonía Neumocócica/epidemiología , Rituximab , Talidomida
5.
Ann Clin Microbiol Antimicrob ; 21(1): 54, 2022 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-36443758

RESUMEN

OBJECTIVES: Among patients with haematological malignancy, bacteraemia is a common complication during chemotherapy-induced neutropenia. Resistance of gram-negative bacteria (GNB) to third-generation cephalosporins (3GC) is increasing. In order to explore the value of using surveillance cultures to guide empirical treatment e.g. choosing between carbapenem versus ceftazidime- we aimed to assess the distribution of pathogens causing bacteraemia in patients with haematological malignancy, and the proportion of 3GC-resistant GNB (3GC-R GNB) bacteraemia that was preceded by 3GC-R GNB colonization. METHODS: Using 11 years of data (2008-2018) from the Dutch national antimicrobial resistance surveillance system, we assessed the prevalence of 3GC-R GNB in episodes of bacteraemia, and the proportion of 3GC-R GNB bacteraemia that was preceded by 3GC-R GNB colonization. Colonization was defined as availability of any GNB surveillance isolate in the year before, independent of the causative micro-organism (time-paired isolates). RESULTS: We included 3887 patients, representing 4142 episodes of bacteraemia. GNB were identified in 715/4142 (17.3%), of which 221 (30.9%) were 3GC-R GNB. In 139 of these 221 patients a time-paired surveillance culture was available. In 76.2% (106/139) of patients these surveillance cultures already showed 3GC-R GNB isolates in the year prior to the culture date of the 3GC-R GNB positive blood isolate. CONCLUSIONS: This multi-centre study shows that in patients with haematological malignancy, the majority of 3GC-R GNB bacteraemia is preceded by 3GC-R GNB colonization. Prospective clinical studies are needed to assess the safety and benefits of the use of surveillance-cultures to guide empirical therapy to restrict the empirical use of carbapenems in this population.


Asunto(s)
Bacteriemia , Neoplasias Hematológicas , Humanos , Estudios Retrospectivos , Estudios Prospectivos , Bacteriemia/tratamiento farmacológico , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/tratamiento farmacológico , Carbapenémicos , Ceftazidima
6.
Br J Cancer ; 124(12): 1978-1987, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33742146

RESUMEN

BACKGROUND: Epidemiological studies and meta-analyses show an association between statin use and a reduced incidence of colorectal cancer (CRC). We have shown that statins act on CRC through bone morphogenetic protein (BMP) signalling, but the exact cellular targets and underlying mechanism of statin action remain elusive. In this study, we set out to assess the influence of statins on global cancer cell signalling by performing an array-based kinase assay using immobilised kinase substrates spanning the entire human kinome. METHODS: CRC cells with or without Lovastatin treatment were used for kinome analysis. Findings on kinome arrays were further confirmed by immunoblotting with activity-specific antibodies. Experiments in different CRC cell lines using immunoblotting, siRNA-mediated knockdown and treatment with specific BMP inhibitor Noggin were performed. The relevance of in vitro findings was confirmed in xenografts and in CRC patients treated with Simvastatin. RESULTS: Kinome analysis can distinguish between non-specific, toxic effects caused by 10 µM of Lovastatin and specific effects on cell signalling caused by 2 µM Lovastatin. Statins induce upregulation of PTEN activity leading to downregulation of the PI3K/Akt/mTOR signalling. Treatment of cells with the specific BMP inhibitor Noggin as well as PTEN knockdown and transfection of cells with a constitutively active form of AKT abolishes the effect of Lovastatin on mTOR phosphorylation. Experiments in xenografts and in patients treated with Simvastatin confirm statin-mediated BMP pathway activation, activation of PTEN and downregulation of mTOR signalling. CONCLUSIONS: Statins induce BMP-specific activation of PTEN and inhibition of PI3K/Akt/mTOR signalling in CRC.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Fosfotransferasas/metabolismo , Proteoma/efectos de los fármacos , Animales , Línea Celular Tumoral , Neoplasias Colorrectales/patología , Femenino , Células HCT116 , Células HT29 , Humanos , Lovastatina/farmacología , Ratones , Ratones Desnudos , Fosfoproteínas/efectos de los fármacos , Fosfoproteínas/metabolismo , Fosforilación/efectos de los fármacos , Fosfotransferasas/efectos de los fármacos , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Proteoma/metabolismo , Transducción de Señal/efectos de los fármacos
7.
J Thromb Thrombolysis ; 52(4): 1068-1073, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34160744

RESUMEN

COVID-19 patients have increased risk of pulmonary embolism (PE), but symptoms of both conditions overlap. Because screening algorithms for PE in COVID-19 patients are currently lacking, PE might be underdiagnosed. We evaluated a screening algorithm in which all patients presenting to the ED with suspected or confirmed COVID-19 routinely undergo D-dimer testing, followed by CT pulmonary angiography (CTPA) if D-dimer is ≥ 1.00 mg/L. Consecutive adult patients presenting to the ED of two university hospitals in Amsterdam, The Netherlands, between 01-10-2020 and 31-12-2020, who had a final diagnosis of COVID-19, were retrospectively included. D-dimer and CTPA results were obtained. Of 541 patients with a final diagnosis of COVID-19 presenting to the ED, 25 (4.6%) were excluded because D-dimer was missing, and 71 (13.1%) because they used anticoagulation therapy. Of 445 included patients, 185 (41.6%; 95%CI 37.0-46.3) had a D-dimer ≥ 1.00 mg/L. CTPA was performed in 169 of them, which showed PE in 26 (15.4%; 95%CI 10.3-21.7), resulting in an overall detection rate of 5.8% (95%CI 3.9-8.4) in the complete study group. In patients with and without PE at CTPA, median D-dimer was 9.84 (IQR 3.90-29.38) and 1.64 (IQR 1.17-3.01), respectively (p < 0.001). PE prevalence increased with increasing D-dimer, ranging from 1.2% (95%CI 0.0-6.4) if D-dimer was 1.00-1.99 mg/L, to 48.6% (95%CI 31.4-66.0) if D-dimer was ≥ 5.00 mg/L. In conclusion, by applying this screening algorithm, PE was identified in a considerable proportion of COVID-19 patients. Prospective management studies should assess if this algorithm safely rules-out PE if D-dimer is < 1.00 mg/L.


Asunto(s)
COVID-19 , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Embolia Pulmonar , Adulto , Angiografía , COVID-19/complicaciones , Servicio de Urgencia en Hospital , Humanos , Países Bajos , Embolia Pulmonar/diagnóstico por imagen , Estudios Retrospectivos
9.
Proc Natl Acad Sci U S A ; 111(46): 16514-9, 2014 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-25368192

RESUMEN

It recently has been recognized that men develop colonic adenomas and carcinomas at an earlier age and at a higher rate than women. In the Apc(Pirc/+) (Pirc) rat model of early colonic cancer, this sex susceptibility was recapitulated, with male Pirc rats developing twice as many adenomas as females. Analysis of large datasets revealed that the Apc(Min/+) mouse also shows enhanced male susceptibility to adenomagenesis, but only in the colon. In addition, WT mice treated with injections of the carcinogen azoxymethane (AOM) showed increased numbers of colonic adenomas in males. The mechanism underlying these observations was investigated by manipulation of hormonal status. The preponderance of colonic adenomas in the Pirc rat model allowed a statistically significant investigation in vivo of the mechanism of sex hormone action on the development of colonic adenomas. Females depleted of endogenous hormones by ovariectomy did not exhibit a change in prevalence of adenomas, nor was any effect observed with replacement of one or a combination of female hormones. In contrast, depletion of male hormones by orchidectomy (castration) markedly protected the Pirc rat from adenoma development, whereas supplementation with testosterone reversed that effect. These observations were recapitulated in the AOM mouse model. Androgen receptor was undetectable in the colon or adenomas, making it likely that testosterone acts indirectly on the tumor lineage. Our findings suggest that indirect tumor-promoting effects of testosterone likely explain the disparity between the sexes in the development of colonic adenomas.


Asunto(s)
Adenoma/epidemiología , Carcinógenos/toxicidad , Neoplasias del Colon/epidemiología , Dihidrotestosterona/toxicidad , Hormonas Esteroides Gonadales/fisiología , Neoplasias Hormono-Dependientes/epidemiología , Adenoma/inducido químicamente , Adenoma/fisiopatología , Adenoma/prevención & control , Poliposis Adenomatosa del Colon/epidemiología , Poliposis Adenomatosa del Colon/genética , Poliposis Adenomatosa del Colon/fisiopatología , Animales , Animales Congénicos , Azoximetano/toxicidad , Neoplasias del Colon/inducido químicamente , Neoplasias del Colon/fisiopatología , Neoplasias del Colon/prevención & control , Modelos Animales de Enfermedad , Estradiol/administración & dosificación , Estradiol/farmacología , Femenino , Genes APC , Terapia de Reemplazo de Hormonas , Humanos , Masculino , Acetato de Medroxiprogesterona/administración & dosificación , Acetato de Medroxiprogesterona/farmacología , Ratones , Ratones Endogámicos C57BL , Mutación , Neoplasias Hormono-Dependientes/fisiopatología , Neoplasias Hormono-Dependientes/prevención & control , Orquiectomía , Especificidad de Órganos , Ovariectomía , Posmenopausia , ARN Mensajero/análisis , Distribución Aleatoria , Ratas , Ratas Endogámicas F344 , Ratas Mutantes , Receptores Androgénicos/biosíntesis , Receptores Androgénicos/genética , Distribución por Sexo , Especificidad de la Especie
11.
Gastroenterology ; 148(1): 170-180.e6, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25307863

RESUMEN

BACKGROUND & AIMS: Indian hedgehog (IHH) is an epithelial-derived signal in the intestinal stroma, inducing factors that restrict epithelial proliferation and suppress activation of the immune system. In addition to these rapid effects of IHH signaling, IHH is required to maintain a stromal phenotype in which myofibroblasts and smooth muscle cells predominate. We investigated the role of IHH signaling during development of intestinal neoplasia in mice. METHODS: Glioma-associated oncogene (Gli1)-CreERT2 and Patched (Ptch)-lacZ reporter mice were crossed with Apc(Min) mice to generate Gli1CreERT2-Rosa26-ZSGreen-Apc(Min) and Ptch-lacZ-Apc(Min) mice, which were used to identify hedgehog-responsive cells. Cyp1a1Cre-Apc (Apc(HET)) mice, which develop adenomas after administration of ß-naphthoflavone, were crossed with mice with conditional disruption of Ihh in the small intestine epithelium. Apc(Min) mice were crossed with mice in which sonic hedgehog (SHH) was overexpressed specifically in the intestinal epithelium. Intestinal tissues were collected and analyzed histologically and by immunohistochemistry and quantitative reverse-transcription polymerase chain reaction. We also analyzed levels of IHH messenger RNA and expression of IHH gene targets in intestinal tissues from patients with familial adenomatous polyposis (n = 18) or sessile serrated adenomas (n = 15) and normal colonic tissue from control patients (n = 12). RESULTS: Expression of IHH messenger RNA and its targets were increased in intestinal adenomas from patients and mice compared with control colon tissues. In mice, IHH signaling was exclusively paracrine, from the epithelium to the stroma. Loss of IHH from Apc(HET) mice almost completely blocked adenoma development, and overexpression of SHH increased the number and size of adenomas that developed. Loss of IHH from Apc(HET) mice changed the composition of the adenoma stroma; cells that expressed α-smooth muscle actin or desmin were lost, along with expression of cyclooxygenase-2, and the number of vimentin-positive cells increased. CONCLUSIONS: Apc mutant epithelial cells secrete IHH to maintain an intestinal stromal phenotype that is required for adenoma development in mice.


Asunto(s)
Adenoma/metabolismo , Biomarcadores de Tumor/metabolismo , Transformación Celular Neoplásica/metabolismo , Proteínas Hedgehog/metabolismo , Neoplasias Intestinales/metabolismo , Transducción de Señal , Células del Estroma/metabolismo , Adenoma/inducido químicamente , Adenoma/genética , Adenoma/patología , Poliposis Adenomatosa del Colon/metabolismo , Poliposis Adenomatosa del Colon/patología , Animales , Comunicación Autocrina , Biomarcadores de Tumor/genética , Estudios de Casos y Controles , Proliferación Celular , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Citocromo P-450 CYP1A1/genética , Modelos Animales de Enfermedad , Células Epiteliales/metabolismo , Células Epiteliales/patología , Regulación Neoplásica de la Expresión Génica , Genes APC , Predisposición Genética a la Enfermedad , Proteínas Hedgehog/genética , Humanos , Hiperplasia , Integrasas/genética , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Neoplasias Intestinales/inducido químicamente , Neoplasias Intestinales/genética , Neoplasias Intestinales/patología , Ratones Transgénicos , Mutación , Comunicación Paracrina , Fenotipo , ARN Mensajero/metabolismo , Células del Estroma/patología , Carga Tumoral , beta-naftoflavona
12.
Gut ; 64(2): 195-202, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24789843

RESUMEN

OBJECTIVE: Stress in the endoplasmic reticulum (ER) leads to activation of the unfolded protein response (UPR). Xbp1, a key component of the UPR has recently been linked to the risk of developing oesophageal squamous cell carcinoma, suggesting an important role for the UPR in the oesophageal epithelium. Here we examined the role of ER stress and the UPR in oesophageal epithelial homoeostasis. DESIGN: We examined the expression of components of the UPR in the oesophageal epithelium. We used a pharmacological approach and a genetic approach to examine the effects of ER stress in vivo in the mouse oesophagus. The oesophagus of these mice was examined using immunohistochemistry and real-time reverse transcription (RT)-PCR. RESULTS: Components of the UPR were heterogeneously expressed in the basal layer of the epithelium. Induction of ER stress by 24-h treatment with thapsigargin resulted in depletion of proliferating cells in the basal layer of the oesophagus and induced differentiation. We next activated the UPR by inducible deletion of the major ER chaperone Grp78 in Ah1Cre-Rosa26-LacZ-Grp78(-/-) mice in which mutant cells could be traced by expression of LacZ. In these mice LacZ-positive mutant cells in the basal layer lost their proliferative capacity, migrated towards the oesophageal lumen and were replaced by LacZ-negative non-mutant cells. We observed no apoptosis in mutant cells. CONCLUSIONS: These results show that ER stress induces epithelial differentiation in precursor cells in the oesophageal epithelium. This UPR induced differentiation may serve as a quality control mechanism that protects against oesophageal cancer development.


Asunto(s)
Estrés del Retículo Endoplásmico/fisiología , Esófago/citología , Animales , Apoptosis/fisiología , Diferenciación Celular/fisiología , Retículo Endoplásmico/ultraestructura , Chaperón BiP del Retículo Endoplásmico , Estrés del Retículo Endoplásmico/efectos de los fármacos , Células Epiteliales/citología , Proteínas de Choque Térmico/deficiencia , Proteínas de Choque Térmico/fisiología , Homeostasis/fisiología , Lactonas/farmacología , Ratones Endogámicos C57BL , Sesquiterpenos/farmacología , Células Madre/citología , Respuesta de Proteína Desplegada/fisiología
14.
Gut ; 63(2): 310-6, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23408349

RESUMEN

BACKGROUND: Hormone replacement therapy increases the risk of developing ulcerative colitis in postmenopausal women. Chronic intestinal inflammation predisposes to colon cancer development, but effects of female hormones on colitis-associated cancer development have not been examined. AIM: To investigate the role of female hormones in the dextran sodium sulfate (DSS)-azoxymethane (AOM) mouse model for colitis-associated cancer. DESIGN: We performed ovariectomies, or sham operations, on mice, and supplemented these animals with indicated hormones. Additionally, we used oestrogen receptor α or ß (Erα or Erß) mutant mice. To study colitis or colitis-associated cancer, we used DSS only, or DSS and AOM, respectively. RESULTS: Ovariectomy protects female mice against colitis-associated tumour development. Hormone replacement in ovariectomised mice with either oestradiol (E2), medroxyprogesterone acetate or a combination of both suggests that oestrogens are the ovary-derived factor that promotes tumour development in the context of inflammatory damage. E2-treated animals showed increased clinical symptoms and Il-6 production upon DSS-induced colitis and enhanced epithelial proliferation. Treatment with E2 markedly increased the numbers of polyps in ovariectomised mice and also strongly promoted tumour progression with all E2-treated animals developing at least one invasive adenocarcinoma, whereas, placebo-treated animals developed adenomas only. Using Er mutant mice, we find that the protumorigenic effect of oestrogen depends on both Erα and Erß. CONCLUSIONS: Our results suggest that oestrogens promote inflammation-associated cancer development by impairing the mucosal response to inflammatory damage.


Asunto(s)
Carcinogénesis/inducido químicamente , Colitis/inducido químicamente , Neoplasias del Colon/inducido químicamente , Modelos Animales de Enfermedad , Estradiol/efectos adversos , Estrógenos/efectos adversos , Medroxiprogesterona/efectos adversos , Animales , Azoximetano/toxicidad , Citocinas/metabolismo , Sulfato de Dextran/toxicidad , Femenino , Terapia de Reemplazo de Hormonas/efectos adversos , Inmunohistoquímica , Ratones , Ovariectomía
15.
Gastroenterology ; 144(1): 134-144.e6, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23041331

RESUMEN

BACKGROUND & AIMS: A fraction of gastrointestinal stromal tumor (GIST) cells overexpress the platelet-derived growth factor receptor (PDGFR)A, although most overexpress KIT. It is not known if this is because these receptor tyrosine kinases have complementary oncogenic potential, or because of heterogeneity in the cellular origin of GIST. Little also is known about why Hedgehog (HH) signaling is activated in some GIST. HH binds to and inactivates the receptor protein patched homolog (PTCH). METHODS: Ptch was conditionally inactivated in mice (to achieve constitutive HH signaling) using a Cre recombinase regulated by the lysozyme M promoter. Cre-expressing cells were traced using R26R-LacZ reporter mice. Tumors were characterized by in situ hybridization, immunohistochemistry, immunoblot, and quantitative reverse-transcriptase polymerase chain reaction analyses. Cell transformation was assessed by soft agar assay. RESULTS: Loss of Ptch from lysozyme M-expressing cells resulted in the development of tumors of GIST-like localization and histology; these were reduced when mice were given imatinib, a drug that targets KIT and PDGFRA. The Hh signaling pathway was activated in the tumor cells, and Pdgfrα, but not Kit, was overexpressed and activated. Lineage tracing revealed that Cre-expressing intestinal cells were Kit-negative. These cells sometimes expressed Pdgfrα and were located near Kit-positive interstitial cells of Cajal. In contrast to KIT, activation of PDGFRA increased anchorage-independent proliferation and was required for tumor formation in mice by cells with activated HH signaling. CONCLUSIONS: Inactivation of Ptch in mice leads to formation of GIST-like tumors that express Pdgfrα, but not Kit. Activation of Pdgfrα signaling appears to facilitate tumorigenesis.


Asunto(s)
Neoplasias Gastrointestinales/genética , Tumores del Estroma Gastrointestinal/metabolismo , Proteínas Hedgehog/genética , Leiomiosarcoma/genética , Proteínas Proto-Oncogénicas c-kit/metabolismo , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Receptores de Superficie Celular/genética , Animales , Benzamidas , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Neoplasias Gastrointestinales/tratamiento farmacológico , Neoplasias Gastrointestinales/metabolismo , Neoplasias Gastrointestinales/patología , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Tumores del Estroma Gastrointestinal/genética , Tumores del Estroma Gastrointestinal/patología , Expresión Génica , Genotipo , Proteínas Hedgehog/metabolismo , Humanos , Mesilato de Imatinib , Integrasas/genética , Integrasas/metabolismo , Mucosa Intestinal/metabolismo , Factores de Transcripción de Tipo Kruppel/metabolismo , Leiomiosarcoma/metabolismo , Ratones , Muramidasa/genética , Muramidasa/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Receptores Patched , Receptor Patched-1 , Piperazinas/uso terapéutico , Regiones Promotoras Genéticas , Inhibidores de Proteínas Quinasas/uso terapéutico , Pirimidinas/uso terapéutico , Receptores de Superficie Celular/metabolismo , Transducción de Señal/genética , Proteína con Dedos de Zinc GLI1 , Proteína Gli2 con Dedos de Zinc , Proteína Gli3 con Dedos de Zinc
16.
Gut ; 62(3): 348-57, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22504664

RESUMEN

OBJECTIVE: In the intestine Hedgehog (Hh) signalling is directed from epithelium to mesenchyme and negatively regulates epithelial precursor cell fate. The role of Hh signalling in the oesophagus has not been studied in vivo. Here the authors examined the role of Hh signalling in epithelial homeostasis of oesophagus. DESIGN: The authors used transgenic mice in which the Hh receptor Patched1 (Ptch1) could be conditionally inactivated in a body-wide manner and mice in which Gli1 could be induced specifically in the epithelium of the skin and oesophagus. Effects on epithelial homeostasis of the oesophagus were examined using immunohistochemistry, in situ hybridisation, transmission electron microscopy and real-time PCR. Hh signalling was examined in patients with oesophageal squamous cell carcinoma (SCC) by quantitative real-time PCR. RESULTS: Sonic Hh is signalled in an autocrine manner in the basal layer of the oesophagus. Activation of Hh signalling resulted in an expansion of the epithelial precursor cell compartment and failure of epithelial maturation and migration. Levels of Hh targets GLI1, HHIP and PTCH1 were increased in SCC compared with normal tissue from the same patients. CONCLUSION: Here the authors find that Hh signalling positively regulates the precursor cell compartment in the oesophageal epithelium in an autocrine manner. Since Hh signalling targets precursor cells in the oesophageal epithelium and signalling is increased in SCCs, Hh signalling may be involved in oesophageal SCC formation.


Asunto(s)
Células Epiteliales/metabolismo , Esófago/citología , Proteínas Hedgehog/fisiología , Transducción de Señal/fisiología , Animales , Carcinoma de Células Escamosas/metabolismo , Diferenciación Celular , Movimiento Celular , Proliferación Celular , Neoplasias Esofágicas/metabolismo , Regulación de la Expresión Génica , Homeostasis/fisiología , Humanos , Inmunohistoquímica , Hibridación in Situ , Ratones , Ratones Transgénicos , Microscopía Electrónica de Transmisión , Reacción en Cadena en Tiempo Real de la Polimerasa
17.
Cancer Lett ; 587: 216678, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38360143

RESUMEN

Endoplasmic reticulum (ER) stress and the adaptive response that follows, termed the unfolded protein response (UPR), are crucial molecular mechanisms to maintain cellular integrity by safeguarding proper protein synthesis. Next to being important in protein homeostasis, the UPR is intricate in cell fate decisions such as proliferation, differentiation, and stemness. In the intestine, stem cells are critical in governing epithelial homeostasis and they are the cell of origin of gastrointestinal malignancies. In this review, we will discuss the role of ER stress and the UPR in the gastrointestinal tract, focusing on stem cells and carcinogenesis. Insights in mechanisms that connect ER stress and UPR with stemness and carcinogenesis may broaden our understanding in the development of cancer throughout the gastrointestinal tract and how we can exploit these mechanisms to target these malignancies.


Asunto(s)
Neoplasias , Respuesta de Proteína Desplegada , Humanos , Estrés del Retículo Endoplásmico/fisiología , Carcinogénesis , Neoplasias/patología , Células Madre/patología , Tracto Gastrointestinal
18.
Gut ; 61(12): 1708-15, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22187071

RESUMEN

BACKGROUND: 5-Aminosalicylic acid (5-ASA) may protect against the development of inflammation-associated colorectal cancer. In vitro data suggest that, in colorectal cancer cells, 5-ASA induces cell cycle arrest, but the molecular mechanism leading to this arrest remains to be determined. AIM: To dissect the signal transduction events that lead to 5-ASA mediated inhibition of proliferation of colorectal cancer cells, focusing on mammalian target of rapamycin (mTOR), a regulator of cell cycle progression. METHODS: The influence of 5-ASA on mTOR signalling was examined in a panel of colorectal cancer cell lines. The effects of 5-ASA on the pathways that control mTOR activity were studied in detail in two different colorectal cancer cell lines, using western blot, siRNA, a phospholipase D (PLD) activity assay, proliferation assays and cell cycle analysis. The phosphorylation status of mTOR and its downstream target, ribosomal protein S6, was studied in colorectal cancers before and after topical 5-ASA treatment. RESULTS: Treatment of colorectal cancer with 5-ASA inhibited mTOR signalling in vitro and in vivo. 5-ASA had no effect on any of the pathways that regulate the activity of the tuberous sclerosis complex in colorectal cancer cells. Both proliferation and mTOR activity depended on PLD, an enzyme that generates phosphatidic acid (PA). 5-ASA treatment inhibited PLD activity and proliferation; these effects could be rescued with exogenous PA. CONCLUSION: 5-ASA interferes with proliferation of colorectal cancer cells via inhibition of PLD-dependent generation of PA and loss of mTOR signalling.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Mesalamina/farmacología , Fosfolipasa D/metabolismo , Transducción de Señal/efectos de los fármacos , Antiinflamatorios no Esteroideos/uso terapéutico , Biomarcadores de Tumor/metabolismo , Western Blotting , Línea Celular Tumoral , Neoplasias Colorrectales/metabolismo , Humanos , Mesalamina/uso terapéutico , Serina-Treonina Quinasas TOR/metabolismo
19.
Int J Med Inform ; 180: 105264, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37890203

RESUMEN

BACKGROUND: Correctly structured problem lists in electronic health records (EHRs) offer major benefits to patient care. Without structured lists, diagnosis information is often scatteredly documented in free text, which may contribute to errors and inefficient information retrieval. This study aims to assess whether EHRs with correctly structured problem lists result in better and faster clinical decision-making compared to non-curated problem lists. METHODS: Two versions of two patient records (A and B) were created in an EHR training environment: one version included diagnosis information structured and coded on the problem list ("correctly structured problem list"), the other version had missing problem list diagnoses and diagnosis information partly documented in free text ("non-curated problem list"). In this single-blinded crossover randomized controlled trial, healthcare providers, who can prescribe medications, from two Dutch university medical center locations first evaluated a randomized version of patient A, then B. Participants were asked to motivate their answer to two medication prescription questions. One (test) question required information similarly presented in both record versions. The second (comparison) question required information documented on problem lists and/or in notes. The primary outcome measure was the correctness of the motivated answer to the comparison question. Secondary outcome measure was the time to answer and motivate both questions correctly. RESULTS: As planned, 160 participants enrolled. Two were excluded for not meeting inclusion criteria. Correctly structured problem lists increased providers' ability to answer the comparison question correctly (56.3 % versus 33.5 %, McNemar odds ratio 2.80 (1.65-4.93) 95 %-CI). Median time to answer both questions correctly was significantly lower for EHRs with correctly structured problem lists (Wilcoxon-signed-rank test p = 0.00002, with incorrect answers coded equally at slowest time). CONCLUSIONS: Correctly structured problem lists lead to better and faster clinical decision-making. Increased structured problem lists usage may be warranted for which implementation policies should be developed.


Asunto(s)
Toma de Decisiones Clínicas , Registros Electrónicos de Salud , Humanos , Prescripciones de Medicamentos , Personal de Salud , Estudios Cruzados
20.
Life Sci Alliance ; 6(11)2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37643866

RESUMEN

In development of colorectal cancer, mutations in APC are often followed by mutations in oncogene KRAS The latter changes cellular metabolism and is associated with the Warburg phenomenon. Glucose-regulated protein 78 (Grp78) is an important regulator of the protein-folding machinery, involved in processing and localization of transmembrane proteins. We hypothesize that targeting Grp78 in Apc and Kras (AK)-mutant intestines interferes with the metabolic phenotype imposed by Kras mutations. In mice with intestinal epithelial mutations in Apc, Kras G12D and heterozygosity for Grp78 (AK-Grp78 HET ) adenoma number and size is decreased compared with AK-Grp78 WT mice. Organoids from AK-Grp78 WT mice exhibited a glycolysis metabolism which was completely rescued by Grp78 heterozygosity. Expression and correct localization of glucose transporter GLUT1 was diminished in AK-Grp78 HET cells. GLUT1 inhibition restrained the increased growth observed in AK-mutant organoids, whereas AK-Grp78 HET organoids were unaffected. We identify Grp78 as a critical factor in Kras-mutated adenomagenesis. This can be attributed to a critical role for Grp78 in GLUT1 expression and localization, targeting glycolysis and the Warburg effect.


Asunto(s)
Chaperón BiP del Retículo Endoplásmico , Animales , Ratones , Proliferación Celular , Glucosa , Transportador de Glucosa de Tipo 1/genética , Glucólisis/genética , Intestinos , Proteínas Proto-Oncogénicas p21(ras)/genética
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