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1.
BMC Cancer ; 21(1): 336, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33789622

RESUMO

BACKGROUND: Pazopanib, a multitargeted tyrosine kinase inhibitor, is recommended as the standard treatment for refractory soft tissue sarcoma (STS). However, there are comparatively few molecular determinants for predicting pazopanib efficacy. Based on correlative studies regarding the predictive impact of PD-L1, we investigated the clinical relevance of PD-L1 expression and evaluated its value for predicting pazopanib efficacy. METHODS: Tumour tissues from patients with advanced STS who went on to receive pazopanib were assessed for PD-L1 expression. Immunohistochemistry was performed using an anti-PD-L1 antibody, and the PD-L1 tumour proportion score (TPS) was calculated as the percentage of at least 100 viable cells with positive expression, defined as TPS ≥ 1%. RESULTS: Among the 67 patients, 8 (11.9%) achieved partial response and a median progression-free survival (PFS) of 4.8 months (95% CI 3.8-5.7). PD-L1 expression in tumour cells was detected in 13 (19.4%) cases and the TPS scores ranged from 1 to 100%, as follows: 0 (n = 54, 80.6%), 1-9% (n = 3, 4.5%), 10-49% (n = 9, 13.4%), and ≥ 50% (n = 1, 1.5%). PD-L1 positive tumours exhibited a poorer response to pazopanib treatment than the PD-L1 negative tumours (0% vs 14.8%, P = 0.07). PD-L1-positive tumours had significantly shorter PFS than the PD-L1-negative tumours (median PFS 2.8 vs 5.1 months, P = 0.003), and PD-L1 positivity was an independent predictor of poor response to pazopanib treatment (HR 2.77, 95% CI; 1.45-5.56, P = 0.006). CONCLUSION: We identified that PD-L1 expression can help predict the clinical outcome of patients with advanced STS treated with pazopanib. Based on our study, stratification should be actively considered in order to identify patients who will benefit from pazopanib or further therapeutic strategies for future clinical trials.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Antígeno B7-H1/metabolismo , Pirimidinas/uso terapêutico , Sarcoma/tratamento farmacológico , Sulfonamidas/uso terapêutico , Adulto , Idoso , Inibidores da Angiogênese/farmacologia , Feminino , Humanos , Indazóis , Masculino , Pessoa de Meia-Idade , Prognóstico , Pirimidinas/farmacologia , Estudos Retrospectivos , Sulfonamidas/farmacologia
2.
Comput Inform Nurs ; 39(12): 1007-1016, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34050055

RESUMO

With the rapid development of information and communications technologies, the medical care paradigm has been transformed, making telenursing a reality. Along with the introduction of telenursing, new changes are anticipated in the following central nursing domains: "human," "environment," "nursing," and "health." Current nursing students living in a hyperconnected world are expected to expand telenursing and foster changes in nursing. Therefore, it is important to understand nursing students' perceptions about telenursing to prepare innovatively for this changing field. This study explored nursing students' subjective perceptions about telenursing in South Korea using Q-methodology. Forty Q-statements, which reflected the nursing metaparadigm, were extracted from 175 generated statements; then, 40 nursing students-recruited purposively through snowball sampling-ranked the set of Q-statements. The data were analyzed using the PQMethod program. Five perceptions concerning telenursing were identified: "concerns and suggestions for telenursing," "complete support for telenursing," "inevitable acceptance of telenursing," "distrust and criticism regarding telenursing," and "optional acceptance of telenursing." This study provides strategies for introducing and implementing telenursing services in countries with commercial 5G coverage and informs policies related to nursing education.


Assuntos
Bacharelado em Enfermagem , Estudantes de Enfermagem , Telenfermagem , Comunicação , Humanos , República da Coreia
3.
Oncology ; 98(11): 817-826, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32892196

RESUMO

BACKGROUND: Developing personalized strategies for cancer has shown good efficacies. METHODS: We assessed the molecular targets programmed death ligand 1 (PD-L1), microsatellite instability (MSI), and PIK3CA. Seventy-four patients with liposarcomas who underwent curative resection were assessed for PD-L1 expression in the tumor and tumor-infiltrating lymphocytes (TILs), mismatch repair proteins (MLH1, PMS2, MSH2, and MSH6) by immunohistochemistry, MSI using polymerase chain reaction, and PIK3CA mutation/amplification using pyrosequencing and fluorescence in situ hybridization. RESULTS: Seventeen (23%) cases were TIL+ (≥1 + expression) and associated with longer 5-year overall survival than those with TIL- tumors (84.4 vs. 60.8%, p = 0.007). Six (35.3%) PD-L1+ tumors were detected only in TIL+ cases, with none detected in tumor cells. Two well-differentiated liposarcomas showed MSI, one low and one high with concurrent loss of MLH1, MSH6, and PMS2. PIK3CA mutation was detected in 7 (9.5%) [exon 9 (n = 4) and exon 20 (n = 3)] and only 1 Q546K mutation was a PD-L1+ tumor. PIK3CA copy number gain was detected in 18 (24.4%) and was associated with TIL+ tumors (p = 0.045). CONCLUSIONS: Our comprehensive immuno-molecular panel suggests that liposarcoma should be categorized based on the molecular genomic subtype for precision medicine.


Assuntos
Antígeno B7-H1/biossíntese , Classe I de Fosfatidilinositol 3-Quinases/genética , Lipossarcoma/genética , Lipossarcoma/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígeno B7-H1/imunologia , Classe I de Fosfatidilinositol 3-Quinases/imunologia , Estudos de Coortes , Feminino , Amplificação de Genes , Humanos , Imuno-Histoquímica , Lipossarcoma/patologia , Lipossarcoma/cirurgia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/patologia , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Mutação , Estudos Retrospectivos , Adulto Jovem
4.
Gastrointest Endosc ; 87(2): 529-539, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28882576

RESUMO

BACKGROUND AND AIMS: Colorectal mucosa-associated lymphoid tissue (MALT) lymphoma is a rare disease. The purpose of this study was to investigate the clinical and endoscopic features of colorectal MALT lymphoma. METHODS: Patients diagnosed with colorectal MALT lymphoma at Asan Medical Center from 2002 to 2016 were eligible. Medical records were reviewed to investigate clinical features and treatment outcomes. Endoscopic pictures were assessed to characterize the endoscopic features of colorectal MALT lymphoma. RESULTS: A total of 51 patients were enrolled. The median age was 60 years (interquartile range, 55-71), and 21 (41%) were men. Twenty-six patients (51%) were asymptomatic. Forty-four patients (86%) were in early disease stages, namely Lugano stages I, II, and IIE. Endoscopic appearances were classified as 4 distinct types: subepithelial tumor type (26 patients, 51%), polyposis type (10 patients, 20%), epithelial mass type (7 patients, 14%), and ileitis type (8 patients, 16%). The rectum (20 patients, 39%) was the most common location, followed by the ileocecal area (15 patients, 30%). An initial endoscopic impression of lymphoma was made in only 7 patients. Forceps biopsy sampling as the initial tissue acquisition method could histologically diagnose MALT lymphoma in 28 of 35 patients (80%). Polypectomy as the initial histologic diagnosis could diagnose MALT lymphoma in 16 of 16 patients. Progression-free and overall survival rates at 5 years were 92% and 94%, respectively. CONCLUSIONS: Colorectal MALT lymphomas show various endoscopic appearances, complicating the endoscopic suspicion of colorectal MALT lymphoma. The prognosis of colorectal MALT lymphoma was excellent.


Assuntos
Neoplasias do Ceco/diagnóstico por imagem , Neoplasias do Ceco/patologia , Linfoma de Zona Marginal Tipo Células B/diagnóstico por imagem , Linfoma de Zona Marginal Tipo Células B/patologia , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Idoso , Doenças Assintomáticas , Biópsia , Neoplasias do Ceco/terapia , Colonoscopia , Intervalo Livre de Doença , Feminino , Humanos , Mucosa Intestinal/patologia , Linfoma de Zona Marginal Tipo Células B/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Retais/terapia , Taxa de Sobrevida
5.
J Pathol ; 237(3): 343-54, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26108453

RESUMO

Keratins (K) are cytoprotective proteins and keratin mutations predispose to the development of multiple human diseases. K19 represents the most widely used marker of biliary and hepatic progenitor cells as well as a marker of ductular reaction that constitutes the basic regenerative response to chronic liver injury. In the present study, we investigated the role of K19 in biliary and hepatic progenitor cells and its importance for ductular reaction. K19 wild-type (WT) and knockout (KO) mice were fed: (a) 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC); (b) cholic acid (CA); (c) a choline-deficient, ethionine-supplemented (CDE) diet; or (d) were subjected to common bile duct ligation (CBDL). The bile composition, liver damage, bile duct proliferation, oval cell content and biliary fibrosis were analysed. In untreated animals, loss of K19 led to redistribution of the K network in biliary epithelial cells (BECs) but to no obvious biliary phenotype. After DDC feeding, K19 KO mice exhibited (compared to WTs): (a) increased cholestasis; (b) less pronounced ductular reaction with reduced ductular proliferation and fewer oval cells; (c) impaired Notch 2 signalling in BECs; (d) lower biliary fibrosis score and biliary bicarbonate concentration. An attenuated oval cell proliferation in K19 KOs was also found after feeding with the CDE diet. K19 KOs subjected to CBDL displayed lower BEC proliferation, oval cell content and less prominent Notch 2 signal. K19 deficiency did not change the extent of CA- or CBDL-induced liver injury and fibrosis. Our results demonstrate that K19 plays an important role in the ductular reaction and might be of importance in multiple chronic liver disorders that frequently display a ductular reaction.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Colangite Esclerosante/metabolismo , Colestase Extra-Hepática/metabolismo , Ducto Colédoco/metabolismo , Células Epiteliais/metabolismo , Queratina-19/deficiência , Cirrose Hepática Biliar/metabolismo , Fígado/metabolismo , Células-Tronco/metabolismo , Animais , Proliferação de Células , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/patologia , Colangite Esclerosante/induzido quimicamente , Colangite Esclerosante/genética , Colangite Esclerosante/patologia , Colestase Extra-Hepática/etiologia , Colestase Extra-Hepática/genética , Colestase Extra-Hepática/patologia , Ácido Cólico , Deficiência de Colina/complicações , Ducto Colédoco/patologia , Ducto Colédoco/cirurgia , Modelos Animais de Doenças , Células Epiteliais/patologia , Etionina , Queratina-19/genética , Ligadura , Fígado/patologia , Cirrose Hepática Biliar/induzido quimicamente , Cirrose Hepática Biliar/genética , Cirrose Hepática Biliar/patologia , Regeneração Hepática , Masculino , Camundongos Knockout , Fenótipo , Piridinas , Transdução de Sinais , Células-Tronco/patologia , Fatores de Tempo
6.
Cell Tissue Res ; 357(1): 267-78, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24770931

RESUMO

Acyl-CoA synthetase 5 (ACSL5), a mitochondrially localized enzyme, catalyzes the synthesis of long-chain fatty acid thioesters and is physiologically involved in pro-apoptotic sensing of enterocytes. The aim of the present study is to identify an ACSL5-dependent regulation of mitochondrially expressed proteins and the characterization of related pathways in normal and diseased human intestinal mucosa. Proteomics of isolated mitochondria from ACSL5 transfectants and CaCo2 controls were performed. ACSL5-dependent protein synthesis was verified with quantitative reverse transcription plus the polymerase chain reaction, Western blotting, short-interfering-RNA-mediated gene silencing and additional cell culture experiments. Lipid changes were analyzed with tandem mass spectrometry. ACSL5-related pathways were characterized in normal mucosa and sporadic adenocarcinomas of the human intestine. In CaCo2 cells transfected with ACSL5, mortalin (HSPA9) was about two-fold increased in mitochondria, whereas cytoplasmic mortalin levels were unchanged. Disturbance of acyl-CoA/sphingolipid metabolism, induced by ACSL5 over-expression, was characterized as crucial. ACSL5-related over-expression of mitochondrial mortalin was found in HEK293 and Lovo (wild-type TP53 [tumor protein p53]) and CaCo2 (p53-negative; TP53 mutated) cells but not in Colo320DM cells (mutated TP53). In normal human intestinal mucosa, an increasing gradient of both ACSL5 and mortalin from bottom to top was observed, whereas p53 (wild-type TP53) decreased. In sporadic intestinal adenocarcinomas with strong p53 immunostaining (mutated TP53), ACSL5-related mortalin expression was heterogeneous. ACSL5-induced mitochondrial mortalin expression is assumed to be a stress response to ACSL5-related changes in lipid metabolism and is regulated by the TP53 status. Uncoupling of ACSL5 and mitochondrial mortalin by mutated TP53 could be important in colorectal carcinogenesis.


Assuntos
Coenzima A Ligases/biossíntese , Neoplasias Colorretais/metabolismo , Enterócitos/metabolismo , Proteínas de Choque Térmico HSP70/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adulto , Idoso , Células CACO-2 , Clonagem Molecular , Coenzima A Ligases/genética , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/patologia , Enterócitos/enzimologia , Enterócitos/patologia , Feminino , Humanos , Mucosa Intestinal/enzimologia , Mucosa Intestinal/metabolismo , Masculino , Pessoa de Meia-Idade , Mitocôndrias/enzimologia , Transfecção
7.
Nat Commun ; 15(1): 685, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263321

RESUMO

We aimed to determine the activity of the anti-VEGF receptor tyrosine-kinase inhibitor, pazopanib, combined with the anti-PD-L1 inhibitor, durvalumab, in metastatic and/or recurrent soft tissue sarcoma (STS). In this single-arm phase 2 trial (NCT03798106), treatment consisted of pazopanib 800 mg orally once a day and durvalumab 1500 mg once every 3 weeks. Primary outcome was overall response rate (ORR) and secondary outcomes included progression-free survival (PFS), overall survival, disease control rate, immune-related response criteria, and safety. The ORR was 30.4% and the trial met the pre-specified endpoint. The median PFS was 7.7 months (95% confidence interval: 5.7-10.4). The common treatment-related adverse events of grades 3-4 included neutropenia (9 [19.1%]), elevated aspartate aminotransferase (7 [14.9%]), alanine aminotransferase (5 [10.6%]), and thrombocytopenia (4 [8.5%]). In a prespecified transcriptomic analysis, the B lineage signature was a significant key determinant of overall response (P = 0.014). In situ analysis also showed that tumours with high CD20+ B cell infiltration and vessel density had a longer PFS (P = 6.5 × 10-4) than those with low B cell infiltration and vessel density, as well as better response (50% vs 12%, P = 0.019). CD20+ B cell infiltration was identified as the only independent predictor of PFS via multivariate analysis. Durvalumab combined with pazopanib demonstrated promising efficacy in an unselected STS cohort, with a manageable toxicity profile.


Assuntos
Anticorpos Monoclonais , Indazóis , Pirimidinas , Sarcoma , Neoplasias de Tecidos Moles , Sulfonamidas , Humanos , Recidiva Local de Neoplasia
9.
Future Sci OA ; 7(5): FSO691, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-34046193

RESUMO

AIM: There are limited data on the feasibility of programmed death ligand-1 (PD-L1) expression as a prognostic biomarker in metastatic angiosarcoma. PATIENTS & METHODS: We retrospectively collected and analyzed the data on PD-L1 expression in 70 angiosarcoma patients who were diagnosed at our center between 2005 and 2019. RESULTS: Thirteen (19%) patients had PD-L1 expression. Metastatic angiosarcoma patients who were PD-L1-negative (n = 24) showed longer median progression-free survival (4.9 vs 1.6 months; p = 0.04) and median overall survival (OS; 10.9 vs 5.4 months; p = 0.01) than those who were PD-L1-positive (n = 4). PD-L1 status proved to be a significant factor for OS. CONCLUSION: Metastatic angiosarcoma patients with PD-L1 expression showed shorter survival. PD-L1 status is an independent prognostic factor for OS in metastatic angiosarcoma patients.

10.
Commun Biol ; 4(1): 449, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33837242

RESUMO

Extreme responders to anticancer therapy are rare among advanced breast cancer patients. Researchers, however, have yet to investigate treatment responses therein on the whole exome level. We performed whole exome analysis to characterize the genomic landscape of extreme responders among metastatic breast cancer patients. Clinical samples were obtained from breast cancer patients who showed exceptional responses to anti-HER2 therapy or hormonal therapy and from those who did not. Matched breast tumor tissue (somatic DNA) and blood samples (germline DNA) were collected from a total of 30 responders and 15 non-responders. Whole exome sequencing using Illumina HiSeq2500 was performed for all 45 patients (90 samples). Somatic single nucleotide variants (SNVs), indels, and copy number variants (CNVs) were identified for the genomes of each patient. Group-specific somatic variants and mutational burden were statistically analyzed. Sequencing of cancer exomes for all patients revealed 1839 somatic SNVs (1661 missense, 120 nonsense, 43 splice-site, 15 start/stop-lost) and 368 insertions/deletions (273 frameshift, 95 in-frame), with a median of 0.7 mutations per megabase (range, 0.08 to 4.2 mutations per megabase). Responders harbored a significantly lower nonsynonymous mutational burden (median, 26 vs. 59, P = 0.02) and fewer CNVs (median 13.6 vs. 97.7, P = 0.05) than non-responders. Multivariate analyses of factors influencing progression-free survival showed that a high mutational burden and visceral metastases were significantly related with disease progression. Extreme responders to treatment for metastatic breast cancer are characterized by fewer nonsynonymous mutations and CNVs.


Assuntos
Neoplasias da Mama/genética , Variações do Número de Cópias de DNA , Genoma Humano , Mutação INDEL , Polimorfismo de Nucleotídeo Único , Adulto , Animais , Feminino , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Pessoa de Meia-Idade , Sequenciamento do Exoma
11.
Cancers (Basel) ; 11(4)2019 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-31003440

RESUMO

Proliferation and differentiation of intestinal epithelial cells is assisted by highly specialized and well-regulated signaling cascades. The Wnt pathway, which is one of the fundamental pathways in the intestine, contributes to the organization of proliferative intestinal crypts by positioning and cycling of intestinal stem cells and their derivatives. The Wnt pathway promotes differentiation of intestinal secretory cell types along the crypt-plateau and crypt-villus axis. In contrast to the Wnt pathway, the intestinal Notch cascade participates in cellular differentiation and directs progenitor cells towards an absorptive fate with diminished numbers of Paneth and goblet cells. Opposing activities of Notch and Wnt signaling in the regulation of intestinal stem cells and the enterocytic cell fate have been elucidated recently. In fact, targeting Notch was able to overcome tumorigenesis of intestinal adenomas, prevented carcinogenesis, and counteracted Paneth cell death in the absence of caspase 8. At present, pharmacological Notch inhibition is considered as an interesting tool targeting the intrinsic Wnt pathway activities in intestinal non-neoplastic disease and carcinogenesis.

12.
Pathol Res Pract ; 213(3): 261-266, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28153554

RESUMO

It has been shown that the metabolism of long chain fatty acids is involved in colorectal carcinogenesis. Acyl-CoA synthetases (ACSL) activate free fatty acids by synthesis of acyl-CoA thioesters. ACSL isoform 5 (ACSL5) is involved in enterocytic differentiation and maturation by regulating both pro-apoptotic and anti-proliferative effects. Whilst impaired expression of ACSL5 has been associated with sporadic colorectal carcinogenesis, little is known about ACSL5 as a prognostic factor. Aim of this retrospective study was to characterize the prognostic impact of ACSL5 expression levels in sporadic colorectal adenocarcinomas. A total of 72 patients with a median follow-up of 54 months was included. Using a standardized immunohistochemical approach, colorectal adenocarcinomas with low (n=41; group 1) or high (n=31; group 2) ACSL5 levels were identified. In a one-year follow-up, tumour recurrence was significantly increased in group 1 (p=0.0279). The finding was independent of the TNM- and UICC-stage in the surgical resections. Frequency of lymph node metastasis and mortality was not different between the groups. In a long-time follow-up no differences were found between the ACSL5 groups. The data indicate that ACSL5 could be an independent prognostic factor for early recurrence of sporadic colorectal adenocarcinoma.


Assuntos
Adenocarcinoma/metabolismo , Coenzima A Ligases/metabolismo , Neoplasias Colorretais/metabolismo , Mucosa Intestinal/metabolismo , Recidiva Local de Neoplasia/metabolismo , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/patologia , Feminino , Seguimentos , Humanos , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia/patologia , Prognóstico , Estudos Retrospectivos
13.
Korean J Gastroenterol ; 68(2): 114-8, 2016 Aug 25.
Artigo em Coreano | MEDLINE | ID: mdl-27554220

RESUMO

Primary biliary mucosa-associated lymphoid tissue (MALT) lymphoma is extremely rare. We report a case of primary biliary MALT lymphoma with obstructive jaundice diagnosed by endoscopic biopsy, without surgical intervention. Obstructive jaundice was relieved by endoscopic drainage and endoscopic biopsy was done simultaneously during endoscopic retrograde cholangiopancreatography. Unnecessary surgical intervention can be avoided after pathological confirmation of lymphoma. The patient received radiotherapy, and is alive without any evidence of recurrence or biliary obstruction. Diagnosis of primary biliary lymphoma is very difficult because of its low prevalence. However, it should always be considered as a differential diagnosis, since when an accurate diagnosis is made, unnecessary surgical intervention can be avoided.


Assuntos
Linfoma de Zona Marginal Tipo Células B/diagnóstico , Linfoma de Zona Marginal Tipo Células B/patologia , Abdome/diagnóstico por imagem , Idoso , Ductos Biliares Intra-Hepáticos , Medula Óssea/patologia , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/patologia , Colangiopancreatografia Retrógrada Endoscópica , Colestase/complicações , Colestase/diagnóstico , Diagnóstico Diferencial , Drenagem , Endoscopia Gastrointestinal , Humanos , Imuno-Histoquímica , Icterícia Obstrutiva/patologia , Linfoma de Zona Marginal Tipo Células B/radioterapia , Masculino , Neprilisina/metabolismo , Tomografia por Emissão de Pósitrons , Stents , Tomografia Computadorizada por Raios X
14.
Tuberc Respir Dis (Seoul) ; 78(3): 293-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26175789

RESUMO

Mycobacterium malmoense is a very rare cause of lung disease in South Korea. We reported the first case of lung disease caused by M. malmoense in an immunocompetent patient. The patient was successfully treated with a 14-month course of antibiotics.

15.
World J Gastroenterol ; 21(6): 1759-64, 2015 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-25684940

RESUMO

AIM: To hypothesize that beta-7 integrin affects cellular migration of both, lymphocytes and enterocytes. METHODS: The nucleoside analog BrdU was ip injected in beta-7-deficient mice (C57BL/6-Itgb(tmlcgn)/J) of male gender and age-matched male C57BL/J J mice (wild type) 4, 20, or 40 h before analysis. The total small intestine was isolated, dissected, and used for morphometrical studies. BrdU-positive epithelial cells were numbered in at least 15 hemi-crypts per duodenum, jejunum, and ileum of each animal. The outer most BrdU-positive cell (cell(max)) was determined per hemi-crypt, numerically documented, and statistically analysed. RESULTS: Integrins containing the beta-7-chain were exclusively expressed on leukocytes. In the small intestinal mucosa of beta-7 integrin-deficient mice the number of intraepithelial lymphocytes was drastically decreased. Moreover, the Peyer's patches of beta-7 integrin-deficient mice appeared hypoplastic. In beta-7 integrin-deficient mice the location of cell(max) was found in a higher position than it was the case for the controls. The difference was already detected at 4 h after BrdU application, but significantly increased with time (40 h after BrdU injection) in all small intestinal segments investigated, i.e., duodenum, jejunum, and ileum. Migration of small intestinal enterocytes was different between the experimental groups measured by cell(max) locations. CONCLUSION: The E-cadherin beta-7 integrin pathway probably controls migration of enterocytes within the small intestinal surface lining epithelial layer.


Assuntos
Movimento Celular , Enterócitos/metabolismo , Cadeias beta de Integrinas/metabolismo , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Animais , Cadeias beta de Integrinas/genética , Mucosa Intestinal/citologia , Intestino Delgado/citologia , Linfócitos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais , Fatores de Tempo
16.
World J Gastroenterol ; 21(15): 4499-508, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-25914458

RESUMO

AIM: To verify the hypothesis that caspase-8 (Casp8), which regulates cellular apoptosis and necroptosis, is critically involved in enterocyte migration. METHODS: Casp8-silenced Caco2 cells were used in migration assays. In addition, enterocyte-specific Casp8 heterozygous (Casp8(+/∆int)) or homozygous knockout mice (Casp8(∆int)) were generated by crossing genetically modified mice carrying loxP recombination sites in intron 2 and 4 of the murine Casp8 gene with transgenic animals expressing a cre-transgene under control of the villin promoter in a pure C57/BL6 genetic background. The nucleoside analog BrdU was injected i.p. in male Casp8(+/∆int) and Casp8(∆int) animals 4 h, 20 h, or 40 h before performing morphometric studies. Locations of anti-BrdU-immunostained cells (cell(max)) in at least 50 hemi-crypts of 6 histoanatomically distinct intestinal mucosal regions were numbered and extracted for statistical procedures. For the mice cohort (n = 28), the walking distance of enterocytes was evaluated from cell(max) within crypt (n = 57), plateau (n = 19), and villus (n = 172) positions, resulting in a total of 6838 observations. Data analysis was performed by fitting a three-level mixed effects model to the data. RESULTS: In cell culture experiments with Caco2 cells, Casp8 knockdown efficiency mediated by RNA interference on Casp8 transcripts was 80% controlled as determined by Western blotting. In the scratch assay, migration of Casp8-deleted Caco2 cells was significantly diminished when compared with controls (Casp8(∆scramble) and Caco2). In BrdU-labeled Casp8(∆int) mice, cell(max) locations were found along the hemi-crypts in a lower position than it was for Casp8(+/∆int) or control (cre-negative) animals. Statistical data analysis with a three-level mixed effects model revealed that in the six different intestinal locations (distinct segments of the small and large intestine), cell movement between the three mice groups differed widely. Especially in duodenal hemi-crypts, enterocyte movement was different between the groups. At 20 h, duodenal cell(max) location was significantly lower in Casp8(∆int) (25.67 ± 2.49) than in Casp8(+/∆int) (35.67 ± 4.78; P < 0.05) or control littermates (44.33 ± 0.94; P < 0.01). CONCLUSION: Casp8-dependent migration of enterocytes is likely involved in intestinal physiology and inflammation-related pathophysiology.


Assuntos
Caspase 8/biossíntese , Movimento Celular , Enterócitos/enzimologia , Intestinos/enzimologia , Animais , Células CACO-2 , Caspase 8/genética , Enterócitos/patologia , Repressão Enzimática , Técnicas de Silenciamento de Genes , Genótipo , Humanos , Doenças Inflamatórias Intestinais/enzimologia , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Intestinos/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Interferência de RNA , Transdução de Sinais , Fatores de Tempo , Transfecção
17.
World J Gastroenterol ; 19(42): 7369-73, 2013 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-24259967

RESUMO

The intestinal mucosa is characterized by a high complexity in terms of structure and functions and allows for a controlled demarcation towards the gut lumen. On the one hand it is responsible for pulping and selective absorption of alimentary substances ensuring the immunological tolerance, on the other hand it prevents the penetration of micro-organisms as well as bacterial outgrowth. The continuous regeneration of surface epithelia along the crypt-villus-axis in the small intestine is crucial to assuring these various functions. The core phenomena of intestinal epithelia regeneration comprise cell proliferation, migration, differentiation, and apoptosis. These partly contrarily oriented processes are molecularly balanced through numerous interacting signaling pathways like Wnt/ß-catenin, Notch and Hedgehog, and regulated by various modifying factors. One of these modifiers is acyl-CoA synthetase 5 (ACSL5). It plays a key role in de novo lipid synthesis, fatty acid degradation and membrane modifications, and regulates several intestinal processes, primarily through different variants of protein lipidation, e.g., palmitoylation. ACSL5 was shown to interact with proapoptotic molecules, and besides seems to inhibit proliferation along the crypt-villus-axis. Because of its proapoptotic and antiproliferative characteristics it could be of significant relevance for intestinal homeostasis, cellular disorder and tumor development.


Assuntos
Coenzima A Ligases/metabolismo , Ácidos Graxos/metabolismo , Mucosa Intestinal/enzimologia , Intestino Delgado/enzimologia , Animais , Apoptose , Proliferação de Células , Homeostase , Humanos , Mucosa Intestinal/patologia , Neoplasias Intestinais/enzimologia , Neoplasias Intestinais/patologia , Intestino Delgado/patologia , Transdução de Sinais , Especificidade por Substrato
18.
World J Gastroenterol ; 19(45): 8163-7, 2013 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-24363505

RESUMO

Colorectal carcinomas (CRCs) are frequently found in industrialized countries and lead to a high incidence of malignancy-related mortality. Defined by histomorphological features, CRCs and their pre-invasive lesions are quite heterogeneous. The underlying molecular mechanisms include genomic instability, genomic mutation of tumor suppressor genes or oncogenes, epigenetic changes, and the microRNA network. The molecular mechanisms are guided by repeated clonal selections. The genotype-to-phenotype relation is assumed to be the great challenge of cancer research and the development of effective targeted therapies. At present a strong genotype-to-phenotype relation is characterized only for a minority of CRCs. Consequently, the molecular characterization of CRCs is essential to interpret histological patterns and to identify prognostic groups as well as patients for targeted therapy.


Assuntos
Neoplasias Colorretais/genética , Transformação Celular Neoplásica/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Estudos de Associação Genética , Predisposição Genética para Doença , Instabilidade Genômica , Humanos , Terapia de Alvo Molecular , Fenótipo , Medicina de Precisão , Prognóstico , Fatores de Risco , Transdução de Sinais
19.
World J Gastrointest Pathophysiol ; 4(4): 94-9, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24244877

RESUMO

The gastrointestinal tract is frequently challenged by pathogens/antigens contained in food and water and the intestinal epithelium must be capable of rapid regeneration in the event of tissue damage. Disruption of the intestinal barrier leads to a number of immune-mediated diseases, including inflammatory bowel disease, food allergy, and celiac disease. The intestinal mucosa is composed of different types of epithelial cells in specific barrier functions. Epithelial cells control surface-associated bacterial populations without disrupting the intestinal microflora that is crucial for host health. They are also capable of modulating mucosal immune system, and are thus essential in maintaining homeostasis in the gut. Thus, the regulation of intestinal epithelial homeostasis is crucial for the maintenance of the structure of the mucosa and the defensive barrier functions. Recent studies have demonstrated that multiple molecular pathways are involved in the regulation of intestinal epithelial cell polarity. These include the Wnt, Notch, Hippo, transforming growth factor-ß (TGF-ß)/bone morphogenetic protein (BMP) and Hedgehog pathways, most of which were identified in lower organisms where they play important roles during embryogenesis. These pathways are also used in adult organisms to regulate multiple self-renewing organs. Understanding the interactions between these molecular mechanisms and intestinal barrier function will therefore provide important insight into the pathogenesis of intestinal-based immune-mediated diseases.

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