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1.
Ann Surg ; 275(5): 933-939, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35185125

RESUMO

OBJECTIVE: The aim of this study was to evaluate the safety and efficacy of a modified CAL-WR. SUMMARY BACKGROUND DATA: The use of segmental colectomy in patients with endoscopically unresectable colonic lesions results in significant morbidity and mortality. CAL-WR is an alternative procedure that may reduce morbidity. METHODS: This prospective multicenter study was performed in 13 Dutch hospitals between January 2017 and December 2019. Inclusion criteria were (1) colonic lesions inaccessible using current endoscopic resection techniques (judged by an expert panel), (2) non-lifting residual/recurrent adenomatous tissue after previous polypectomy or (3) an undetermined resection margin after endoscopic removal of a low-risk pathological T1 (pT1) colon carcinoma. Thirty-day morbidity, technical success rate and radicality were evaluated. RESULTS: Of the 118 patients included (56% male, mean age 66 years, standard deviation ± 8 years), 66 (56%) had complex lesions unsuitable for endoscopic removal, 34 (29%) had non-lifting residual/recurrent adenoma after previous polypectomy and 18 (15%) had uncertain resection margins after polypectomy of a pT1 colon carcinoma. CAL-WR was technically successful in 93% and R0 resection was achieved in 91% of patients. Minor complications (Clavien-Dindo i-ii) were noted in 7 patients (6%) and an additional oncologic segmental resection was performed in 12 cases (11%). Residual tissue at the scar was observed in 5% of patients during endoscopic follow-up. CONCLUSIONS: CAL-WR is an effective, organ-preserving approach that results in minor complications and circumvents the need for major surgery. CAL-WR, therefore, deserves consideration when endoscopic excision of circumscribed lesions is impossible or incomplete.


Assuntos
Adenoma , Carcinoma , Neoplasias do Colo , Pólipos do Colo , Laparoscopia , Idoso , Carcinoma/cirurgia , Neoplasias do Colo/patologia , Neoplasias do Colo/cirurgia , Pólipos do Colo/patologia , Pólipos do Colo/cirurgia , Colonoscopia/métodos , Feminino , Humanos , Laparoscopia/métodos , Masculino , Margens de Excisão , Estudos Prospectivos , Estudos Retrospectivos
2.
Hum Mol Genet ; 27(14): 2490-2501, 2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29688337

RESUMO

Huntington's disease (HD) is the most common neurodegenerative disorder for which no effective cure is yet available. Although several agents have been identified to provide benefits so far, the number of therapeutic options remains limited with only symptomatic treatment available. Over the past few years, we have demonstrated that sphingolipid-based approaches may open the door to new and more targeted treatments for the disease. In this study, we investigated the therapeutic potential of stimulating sphingosine-1-phosphate (S1P) receptor 5 by the new selective agonist A-971432 (provided by AbbVie) in R6/2 mice, a widely used HD animal model. Chronic administration of low-dose (0.1 mg/kg) A-971432 slowed down the progression of the disease and significantly prolonged lifespan in symptomatic R6/2 mice. Such beneficial effects were associated with activation of pro-survival pathways (BDNF, AKT and ERK) and with reduction of mutant huntingtin aggregation. A-971432 also protected blood-brain barrier (BBB) homeostasis in the same mice. Interestingly, when administered early in the disease, before any overt symptoms, A-971432 completely protected HD mice from the classic progressive motor deficit and preserved BBB integrity. Beside representing a promising strategy to take into consideration for the development of alternative therapeutic options for HD, selective stimulation of S1P receptor 5 may be also seen as an effective approach to target brain vasculature defects in the disease.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Proteína Huntingtina/genética , Doença de Huntington/tratamento farmacológico , Agregação Patológica de Proteínas/tratamento farmacológico , Receptores de Lisoesfingolipídeo/genética , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Fator Neurotrófico Derivado do Encéfalo/genética , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Doença de Huntington/genética , Doença de Huntington/patologia , Camundongos , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos , Agregação Patológica de Proteínas/fisiopatologia , Proteínas Proto-Oncogênicas c-akt/genética , Receptores de Lisoesfingolipídeo/agonistas
3.
Mod Pathol ; 33(12): 2626-2636, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32581367

RESUMO

Advanced colorectal cancer (CRC) consensus molecular subtype 4 (CMS4) or CRC with a low immunoscore is associated with shorter survival times. Non-metastatic CRC with microsatellite instability (MSI) is associated with a lower risk of recurrence. We evaluated outcome (lymph node metastases [LNM] or cancer recurrence) in these tumor subtypes in patients with surgically-removed non-pedunculated T1 CRC by performing a multicenter case-cohort study. We included all patients in 13 hospitals in the Netherlands from 2000-2014 (n = 651). We randomly selected a subgroup of patients (n = 223) and all patients with LNM or recurrence (n = 63), and median follow-up of 44 months. We centrally reviewed tumor-slides, and constructed and immunostained tissue microarrays determining MSI, CMS (MSI/CMS1, CMS2/3, or CMS4), and immunoscore (I-low/I-high). We used weighted Cox proportional hazard models to evaluate the association of MSI, CMS, and immunoscore with LNM or recurrence, adjusting for conventional histologic risk factors. In the randomly selected subgroup of patients, 7.1% of tumors were MSI/CMS1, 91.0% CMS2/3, 1.8% CMS4, and 25% I-low. In the case-cohort, patients with CMS4 tumors had an increased risk for LNM or recurrence compared with patients with tumors of other CMSs (adjusted hazard ratio [HR], 3.97; 95% CI, 1.12-14.06; P = 0.03). Albeit not significant, tumors with MSI had a lower risk for LNM or recurrence than other tumor subtypes (adjusted HR, 0.52; 95% CI, 0.12-2.30; P = 0.39), whereas tumors with a low immunoscore had an increased risk for LNM or recurrence (adjusted HR, 1.30; 95% CI, 0.68-2.48; P = 0.43). In conclusion, in a case-cohort study of patients with non-pedunculated T1 CRC, MSI, and immunoscore were not significantly associated with adverse outcome after surgery. CMS4 substantially increased the risk of adverse outcome. However, CMS4 is rare in T1 CRCs, limiting its value for determining the risk in patients.


Assuntos
Adenocarcinoma , Biomarcadores Tumorais/análise , Neoplasias Colorretais , Enzimas Reparadoras do DNA/análise , Imuno-Histoquímica , Instabilidade de Microssatélites , Adenocarcinoma/química , Adenocarcinoma/genética , Adenocarcinoma/secundário , Adenocarcinoma/cirurgia , Idoso , Estudos de Casos e Controles , Neoplasias Colorretais/química , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Países Baixos , Fenótipo , Valor Preditivo dos Testes , Fatores de Tempo , Análise Serial de Tecidos , Resultado do Tratamento
4.
Gastrointest Endosc ; 91(1): 142-152.e3, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31525362

RESUMO

BACKGROUND AND AIMS: In contrast to the adverse event (AE) risk of endoscopic resection (ER) of adenomas, the intra- and postprocedural AE risks of ER of T1 colorectal cancer (CRC) are scarcely reported in the literature. It is unclear whether ER of early CRCs, which grow into the submucosal layer and sometimes show incomplete lifting, is associated with an increased AE risk. We aimed to identify the AE rate after ER of T1 CRCs and to identify the risk factors associated with these AEs. METHODS: Medical records of patients with T1 CRCs diagnosed between 2000 and 2014 in 15 hospitals in the Netherlands were reviewed. Patients who underwent primary ER were selected. The primary outcome was the occurrence of endoscopy-related AEs. The secondary outcome was the identification of risk factors. Multivariate logistic regression was performed. RESULTS: Endoscopic AEs occurred in 59 of 1069 (5.5%) patients, among which 37.3% were classified as mild, 59.3% as moderate, and 3.4% as severe. AEs were postprocedural bleeding (n = 40, 3.7%), perforation (n = 13, 1.2%), and postpolypectomy electrocoagulation syndrome (n = 6, 0.6%). No fatal AEs were observed. Independent predictors for AEs were age >70 years (odds ratio, 2.11; 95% confidence interval, 1.12-3.96) and tumor size >20 mm (odds ratio, 2.22; 95% confidence interval, 1.05-4.69). CONCLUSIONS: In this large multicenter retrospective cohort study, AE rates of ER of T1 CRC (5.5%) are comparable with reported AE rates for adenomas. Larger tumor size and age >70 years are independent predictors for AEs. This study suggests that endoscopic treatment of T1 CRCs is not associated with an increased periprocedural AE risk.


Assuntos
Carcinoma/cirurgia , Neoplasias Colorretais/cirurgia , Ressecção Endoscópica de Mucosa/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Idoso , Carcinoma/patologia , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Países Baixos , Estudos Retrospectivos , Fatores de Risco
5.
Gut ; 68(2): 271-279, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29298873

RESUMO

OBJECTIVE: This study evaluated the preresection accuracy of optical diagnosis of T1 colorectal cancer (CRC) in large non-pedunculated colorectal polyps (LNPCPs). DESIGN: In this multicentre prospective study, endoscopists predicted the histology during colonoscopy in consecutive patients with LNPCPs using a standardised procedure for optical assessment. The presence of morphological features assessed with white light, and vascular and surface pattern with narrow-band imaging (NBI) were recorded, together with the optical diagnosis, the confidence level of prediction and the recommended treatment. A risk score chart was developed and validated using a multivariable mixed effects binary logistic least absolute shrinkage and selection (LASSO) model. RESULTS: Among 343 LNPCPs, 47 cancers were found (36 T1 CRCs and 11 ≥T2 CRCs), of which 11 T1 CRCs were superficial invasive T1 CRCs (23.4% of all malignant polyps). Sensitivity and specificity for optical diagnosis of T1 CRC were 78.7% (95% CI 64.3 to 89.3) and 94.2% (95% CI 90.9 to 96.6), and 63.3% (95% CI 43.9 to 80.1) and 99.0% (95% CI 97.1 to 100.0) for optical diagnosis of endoscopically unresectable lesions (ie, ≥T1 CRC with deep invasion), respectively. A LASSO-derived model using white light and NBI features discriminated T1 CRCs from non-invasive polyps with a cross-validation area under the curve (AUC) of 0.85 (95% CI 0.80 to 0.90). This model was validated in a temporal validation set of 100 LNPCPs (AUC of 0.81; 95% CI 0.66 to 0.96). CONCLUSION: Our study provides insights in the preresection accuracy of optical diagnosis of T1 CRC. Sensitivity is still limited, so further studies will show how the risk score chart could be improved and finally used for clinical decision making with regard to the type of endoresection to be used and whether to proceed to surgery instead of endoscopy. TRIAL REGISTRATION NUMBER: NTR5561.


Assuntos
Pólipos do Colo/diagnóstico por imagem , Neoplasias Colorretais/diagnóstico por imagem , Imagem de Banda Estreita/métodos , Idoso , Pólipos do Colo/patologia , Colonoscopia , Neoplasias Colorretais/patologia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estudos Prospectivos , Medição de Risco
6.
Gastroenterology ; 154(6): 1647-1659, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29366842

RESUMO

BACKGROUND & AIMS: Most patients with pedunculated T1 colorectal tumors referred for surgery are not found to have lymph node metastases, and were therefore unnecessarily placed at risk for surgery-associated complications. We aimed to identify histologic factors associated with need for surgery in patients with pedunculated T1 colorectal tumors. METHODS: We performed a cohort-nested matched case-control study of 708 patients diagnosed with pedunculated T1 colorectal tumors at 13 hospitals in The Netherlands, from January 1, 2000 through December 31, 2014, followed for a median of 44 months (interquartile range, 20-80 months). We identified 37 patients (5.2%) who required surgery (due to lymph node, intramural, or distant metastases). These patients were matched with patients with pedunculated T1 colorectal tumors without a need for surgery (no metastases, controls, n = 111). Blinded pathologists analyzed specimens from each tumor, stained with H&E. We evaluated associations between histologic factors and patient need for surgery using univariable conditional logistic regression analysis. We used multivariable least absolute shrinkage and selection operator (LASSO; an online version of the LASSO model is available at: http://t1crc.com/calculator/) regression to develop models for identification of patients with tumors requiring surgery, and tested the accuracy of our model by projecting our case-control data toward the entire cohort (708 patients). We compared our model with previously developed strategies to identify high-risk tumors: conventional model 1 (based on poor differentiation, lymphovascular invasion, or Haggitt level 4) and conventional model 2 (based on poor differentiation, lymphovascular invasion, Haggitt level 4, or tumor budding). RESULTS: We identified 5 histologic factors that differentiated cases from controls: lymphovascular invasion, Haggitt level 4 invasion, muscularis mucosae type B (incompletely or completely disrupted), poorly differentiated clusters and tumor budding, which identified patients who required surgery with an area under the curve (AUC) value of 0.83 (95% confidence interval, 0.76-0.90). When we used a clinically plausible predicted probability threshold of ≥4.0%, 67.5% (478 of 708) of patients were predicted to not need surgery. This threshold identified patients who required surgery with 83.8% sensitivity (95% confidence interval, 68.0%-93.8%) and 70.3% specificity (95% confidence interval, 60.9%-78.6%). Conventional models 1 and 2 identified patients who required surgery with lower AUC values (AUC, 0.67; 95% CI, 0.60-0.74; P = .002 and AUC, 0.64; 95% CI, 0.58-0.70; P < .001, respectively) than our LASSO model. When we applied our LASSO model with a predicted probability threshold of ≥4.0%, the percentage of missed cases (tumors mistakenly assigned as low risk) was comparable (6 of 478 [1.3%]) to that of conventional model 1 (4 of 307 [1.3%]) and conventional model 2 (3 of 244 [1.2%]). However, the percentage of patients referred for surgery based on our LASSO model was much lower (32.5%, n = 230) than that for conventional model 1 (56.6%, n = 401) or conventional model 2 (65.5%, n = 464). CONCLUSIONS: In a cohort-nested matched case-control study of 708 patients with pedunculated T1 colorectal carcinomas, we developed a model based on histologic features of tumors that identifies patients who require surgery (due to high risk of metastasis) with greater accuracy than previous models. Our model might be used to identify patients most likely to benefit from adjuvant surgery.


Assuntos
Colonoscopia/estatística & dados numéricos , Neoplasias Colorretais/patologia , Modelos Estatísticos , Seleção de Pacientes , Medição de Risco/estatística & dados numéricos , Idoso , Área Sob a Curva , Estudos de Casos e Controles , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Mucosa Intestinal/patologia , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Medição de Risco/métodos , Fatores de Risco , Sensibilidade e Especificidade
7.
Clin Gastroenterol Hepatol ; 17(6): 1112-1120.e1, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30130623

RESUMO

BACKGROUND & AIMS: Risk stratification for adverse events, such as metastasis to lymph nodes, is based only on histologic features of tumors. We aimed to compare adverse outcomes of pedunculated vs nonpedunculated T1 colorectal cancers (CRC). METHODS: We performed a retrospective study of 1656 patients diagnosed with T1CRC from 2000 through 2014 at 14 hospitals in The Netherlands. The median follow-up time of patients was 42.5 months (interquartile range, 18.5-77.5 mo). We evaluated the association between tumor morphology and the primary composite end point, adverse outcome, adjusted for clinical variables, histologic variables, resection margins, and treatment approach. Adverse outcome was defined as metastasis to lymph nodes, distant metastases, local recurrence, or residual tissue. Secondary end points were tumor metastasis, recurrence, and incomplete resection. RESULTS: Adverse outcome occurred in 67 of 723 patients (9.3%) with pedunculated T1CRCs vs 155 of 933 patients (16.6%) with nonpedunculated T1CRCs. Pedunculated morphology was independently associated with decreased risk of adverse outcome (adjusted odds ratio [OR], 0.59; 95% CI, 0.42-0.83; P = .003). Metastasis, incomplete resection, and recurrence were observed in 5.8%, 4.6%, and 3.9% of pedunculated T1CRCs vs 10.6%, 8.0%, and 6.6% of nonpedunculated T1CRCs, respectively. Pedunculated morphology was independently associated with a reduced risk of metastasis (adjusted OR, 0.62; 95% CI, 0.41-0.94; P = .03), incomplete resection (adjusted OR, 0.57; 95% CI, 0.36-0.91; P = .02), and recurrence (adjusted hazard ratio, 0.52; 95% CI, 0.32-0.85; P = .009). Metastasis, incomplete resection, and recurrence did not differ significantly between low-risk pedunculated vs nonpedunculated T1CRCs (0.8% vs 2.9%, P = .38; 1.5% vs 0%, P = .99; 1.5% vs 0%; P = .99). However, incomplete resection and recurrence were significantly lower for high-risk pedunculated vs nonpedunculated T1CRCs (6.5% vs 12.5%; P = .007; 4.4% vs 8.6%; P = .03). CONCLUSIONS: In a retrospective study of patients with T1CRC, we found pedunculated morphology to be associated independently with a decreased risk of adverse outcome in a T1CRC population at high risk of adverse outcome. Incorporating morphologic features of tumors in risk assessment could help predict outcomes of patients with T1CRC and help identify the best candidates for surgery.


Assuntos
Colonoscopia/métodos , Neoplasias Colorretais/diagnóstico , Recidiva Local de Neoplasia/epidemiologia , Estadiamento de Neoplasias , Medição de Risco/métodos , Idoso , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/secundário , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/diagnóstico , Países Baixos/epidemiologia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida/tendências , Fatores de Tempo
8.
BMC Med ; 15(1): 129, 2017 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-28705200

RESUMO

BACKGROUND: In patients with stage II colorectal cancer (CRC) the number of surgically retrieved lymph nodes (LNs) is associated with prognosis, resulting in a minimum of 10-12 retrieved LNs being recommended for this stage. Current guidelines do not provide a recommendation regarding LN yield in T1 CRC. Studies evaluating LN yield in T1 CRC suggest that such high LN yields are not feasible in this early stage, and a lower LN yield might be appropriate. We aimed to validate the cut-off of 10 retrieved LNs on risk for recurrent cancer and detection of LN metastasis (LNM) in T1 CRC, and explored whether this number is feasible in clinical practice. METHODS: Patients diagnosed with T1 CRC and treated with surgical resection between 2000 and 2014 in thirteen participating hospitals were selected from the Netherlands Cancer Registry. Medical records were reviewed to collect additional information. The association between LN yield and recurrence and LNM respectively were analyzed using 10 LNs as cut-off. Propensity score analysis using inverse probability weighting (IPW) was performed to adjust for clinical and histological confounding factors (i.e., age, sex, tumor location, size and morphology, presence of LNM, lymphovascular invasion, depth of submucosal invasion, and grade of differentiation). RESULTS: In total, 1017 patients with a median follow-up time of 49.0 months (IQR 19.6-81.5) were included. Four-hundred five patients (39.8%) had a LN yield ≥ 10. Forty-one patients (4.0%) developed recurrence. LN yield ≥ 10 was independently associated with a decreased risk for recurrence (IPW-adjusted HR 0.20; 95% CI 0.06-0.67; P = 0.009). LNM were detected in 84 patients (8.3%). LN yield ≥ 10 was independently associated with increased detection of LNM (IPW-adjusted OR 2.27; 95% CI 1.39-3.69; P = 0.001). CONCLUSIONS: In this retrospective observational study, retrieving < 10 LNs was associated with an increased risk of CRC recurrence, advocating the importance to perform an appropriate oncologic resection of the draining LNs and diligent LN search when patients with T1 CRC at high-risk for LNM are referred for surgical resection. Given that both gastroenterologists, surgeons and pathologists will encounter T1 CRCs with increasing frequency due to the introduction of national screening programs, awareness on the consequences of an inadequate LN retrieval is of utmost importance.


Assuntos
Neoplasias Colorretais/patologia , Linfonodos/patologia , Idoso , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Estudos Longitudinais , Linfonodos/cirurgia , Metástase Linfática , Masculino , Países Baixos , Prognóstico , Estudos Retrospectivos
9.
Mod Pathol ; 30(1): 104-112, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27713422

RESUMO

T1 colorectal cancer can be mimicked by pseudo-invasion in pedunculated polyps. British guidelines are currently one of the few which recommend diagnostic confirmation of T1 colorectal cancer by a second pathologist. The aim of this study was to provide insights into the accuracy of histological diagnosis of pedunculated T1 colorectal cancer in daily clinical practice. A sample of 128 cases diagnosed as pedunculated T1 colorectal cancer between 2000 and 2014 from 10 Dutch hospitals was selected for histological review. Firstly, two Dutch expert gastrointestinal pathologists reviewed all hematoxylin-eosin stained slides. In 20 cases the diagnosis T1 colorectal cancer was not confirmed (20/128; 16%). The discordant cases were subsequently discussed with a third Dutch gastrointestinal pathologist and a consensus diagnosis was agreed. The revised diagnoses were pseudo-invasion in 10 cases (10/128; 8%), high-grade dysplasia in 4 cases (4/128; 3%), and equivocal in 6 cases (6/128; 5%). To further validate the consensus diagnosis, the discordant cases were reviewed by an independent expert pathologist from the United Kingdom. A total of 39 cases were reviewed blindly including the 20 cases with a revised diagnosis and 19 control cases where the Dutch expert panel agreed with the original reporting pathologists diagnosis. In 19 of the 20 cases with a revised diagnosis the British pathologist agreed that T1 colorectal cancer could not be confirmed. Additionally, amongst the 19 control cases the British pathologist was unable to confirm T1 colorectal cancer in a further 4 cases and was equivocal in 3 cases. In conclusion, both generalist and expert pathologists experience diagnostic difficulty distinguishing pseudo-invasion and high-grade dysplasia from T1 colorectal cancer. In order to prevent overtreatment, review of the histology of pedunculated T1 colorectal cancers by a second pathologist should be considered with discussion of these cases at a multidisciplinary meeting.


Assuntos
Colo/patologia , Neoplasias do Colo/diagnóstico , Pólipos do Colo/diagnóstico , Neoplasias Colorretais/diagnóstico , Invasividade Neoplásica/patologia , Idoso , Neoplasias do Colo/patologia , Pólipos do Colo/patologia , Neoplasias Colorretais/patologia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Encaminhamento e Consulta , Sensibilidade e Especificidade
10.
Hum Mol Genet ; 20(24): 4865-78, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21920940

RESUMO

Spinal muscular atrophy (SMA), a frequent neurodegenerative disease, is caused by reduced levels of functional survival of motoneuron (SMN) protein. SMN is involved in multiple pathways, including RNA metabolism and splicing as well as motoneuron development and function. Here we provide evidence for a major contribution of the Rho-kinase (ROCK) pathway in SMA pathogenesis. Using an in vivo protein interaction system based on SUMOylation of proteins, we found that SMN is directly interacting with profilin2a. Profilin2a binds to a stretch of proline residues in SMN, which is heavily impaired by a novel SMN2 missense mutation (S230L) derived from a SMA patient. In different SMA models, we identified differential phosphorylation of the ROCK-downstream targets cofilin, myosin-light chain phosphatase and profilin2a. We suggest that hyper-phosphorylation of profilin2a is the molecular link between SMN and the ROCK pathway repressing neurite outgrowth in neuronal cells. Finally, we found a neuron-specific increase in the F-/G-actin ratio that further support the role of actin dynamics in SMA pathogenesis.


Assuntos
Atrofia Muscular Espinal/metabolismo , Profilinas/metabolismo , Transdução de Sinais , Proteína 1 de Sobrevivência do Neurônio Motor/metabolismo , Quinases Associadas a rho/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Animais , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Cones de Crescimento/metabolismo , Cones de Crescimento/patologia , Humanos , Camundongos , Modelos Biológicos , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Atrofia Muscular Espinal/patologia , Proteínas Mutantes/metabolismo , Mutação de Sentido Incorreto/genética , Neuritos/metabolismo , Fosforilação , Ligação Proteica , Ratos , Proteína 1 de Sobrevivência do Neurônio Motor/genética
11.
United European Gastroenterol J ; 11(6): 551-563, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37300377

RESUMO

BACKGROUND: The role of radiological staging and surveillance imaging is under debate for T1 colorectal cancer (CRC) as the risk of distant metastases is low and imaging may lead to the detection of incidental findings. OBJECTIVE: The aim of this study was to evaluate the yield of radiological staging and surveillance imaging for T1 CRC. METHODS: In this retrospective multicenter cohort study, all patients of 10 Dutch hospitals with histologically proven T1 CRC who underwent radiological staging in the period 2000-2014 were included. Clinical characteristics, pathological, endoscopic, surgical and imaging reports at baseline and during follow-up were recorded and analyzed. Patients were classified as high-risk T1 CRC if at least one of the histological risk factors (lymphovascular invasion, poor tumor differentiation, deep submucosal invasion or positive resection margins) was present and as low-risk when all risk factors were absent. RESULTS: Of the 628 included patients, 3 (0.5%) had synchronous distant metastases, 13 (2.1%) malignant incidental findings and 129 (20.5%) benign incidental findings at baseline staging. Radiological surveillance was performed among 336 (53.5%) patients. The 5-year cumulative incidence of distant recurrence, malignant and benign incidental findings were 2.4% (95% confidence interval (CI): 1.1%-5.4%), 2.5% (95% CI: 0.6%-10.4%) and 18.3% (95% CI: 13.4%-24.7%), respectively. No distant metastatic events occurred among low-risk T1 CRC patients. CONCLUSION: The risk of synchronous distant metastases and distant recurrence in T1 CRC is low, while there is a substantial risk of detecting incidental findings. Radiological staging seems unnecessary prior to local excision of suspected T1 CRC and after local excision of low-risk T1 CRC. Radiological surveillance should not be performed in patients with low-risk T1 CRC.


Assuntos
Neoplasias Colorretais , Humanos , Estudos de Coortes , Fatores de Risco , Radiografia , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/epidemiologia
12.
Proc Natl Acad Sci U S A ; 106(31): 12747-52, 2009 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-19617559

RESUMO

Nuclear bodies are distinct subnuclear structures. The survival of motoneuron (SMN) gene is mutated or deleted in patients with the neurodegenerative disease spinal muscular atrophy (SMA). The gene product SMN is a marker protein for one class of nuclear bodies denoted as nuclear gems. SMN has also been found in Cajal bodies, which co-localize with gems in many cell types. Interestingly, SMA patients display a reduced number of gems. Little is known about the regulation of nuclear body formation and stabilization. We have previously shown that a nuclear isoform of the fibroblast growth factor-2 (FGF-2(23)) binds directly to SMN. In this study, we analyzed the consequences of FGF-2(23) binding to SMN with regard to nuclear body formation. On a molecular level, we showed that FGF-2(23) competed with Gemin2 (a component of the SMN complex that is necessary for gem stabilization) for binding to SMN. Down-regulation of Gemin2 by siRNA caused destabilization of SMN-positive nuclear bodies. This process is reflected in both cellular and in vivo systems by a negative regulatory function of FGF-2 in nuclear body formation: in HEK293 cells, FGF-2(23) decreased the number of SMN-positive nuclear bodies. The same effect could be observed in motoneurons of FGF-2 transgenic mice. This study demonstrates the functional role of a growth factor in the regulation of structural entities of the nucleus.


Assuntos
Corpos Enovelados/fisiologia , Fator 2 de Crescimento de Fibroblastos/fisiologia , Gêmeos de Corpos Enovelados/fisiologia , Animais , Humanos , Imunoprecipitação , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/fisiologia , Proteínas de Ligação a RNA/fisiologia , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/fisiologia , Proteínas do Complexo SMN/análise , Proteínas do Complexo SMN/fisiologia
13.
Eur J Pharmacol ; 934: 175301, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36191631

RESUMO

In this study we aimed to reduce tau pathology, a hallmark of Alzheimer's Disease (AD), by activating mTOR-dependent autophagy in a transgenic mouse model of tauopathy by long-term dosing of animals with mTOR-inhibitors. Rapamycin treatment reduced the burden of hyperphosphorylated and aggregated pathological tau in the cerebral cortex only when applied to young mice, prior to the emergence of pathology. Conversely, PQR530 which exhibits better brain exposure and superior pharmacokinetic properties, reduced tau pathology even when the treatment started after the onset of pathology. Our results show that dosing animals twice per week with PQR530 resulted in intermittent, rather than sustained target engagement. Nevertheless, this pulse-like mTOR inhibition followed by longer intervals of re-activation was sufficient to reduce tau pathology in the cerebral cortex in P301S tau transgenic mice. This suggests that balanced therapeutic dosing of blood-brain-barrier permeable mTOR-inhibitors can result in a disease-modifying effect in AD and at the same time prevents toxic side effects due to prolonged over activation of autophagy.


Assuntos
Doença de Alzheimer , Animais , Camundongos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Proteínas tau/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Camundongos Transgênicos , Encéfalo , Sirolimo/farmacologia , Modelos Animais de Doenças
14.
Artigo em Inglês | MEDLINE | ID: mdl-33566452

RESUMO

BACKGROUND: Current risk stratification models for early invasive (T1) colorectal cancer are not able to discriminate accurately between prognostic favourable and unfavourable tumours, resulting in over-treatment of a large (>80%) proportion of T1 colorectal cancer patients. The tumour-stroma ratio (TSR), which is a measure for the relative amount of desmoplastic tumour stroma, is reported to be a strong independent prognostic factor in advanced-stage colorectal cancer, with a high stromal content being associated with worse prognosis and survival. We aimed to investigate whether the TSR predicts clinical outcome in patients with non-pedunculated T1 colorectal cancer. METHODS: Haematoxylin and eosin (H&E)-stained tumour tissue slides from a retrospective multicentre case cohort of patients with nonpedunculated surgically treated T1 colorectal cancer were assessed for TSR by two independent observers who were blinded for clinical outcomes. The primary end point was adverse outcome, which was defined as the presence of lymph node metastasis in the resection specimen or colorectal cancer recurrence during follow-up. RESULTS: All 261 patients in the case cohort had H&E slides available for TSR scoring. Of these, 183 were scored as stroma-low, and 78 were scored as stroma-high. There was moderate inter-observer agreement κ = 0.42). In total, 41 patients had lymph node metastasis, 17 patients had recurrent cancer and five had both. Stroma-high tumours were not associated with an increased risk for an adverse outcome (adjusted hazard ratio = 0.66, 95% confidence interval 0.37-1.18; p = 0.163). CONCLUSIONS: Our study emphasises that existing prognosticators may not be simply extrapolated to T1 colorectal cancers, even though their prognostic value has been widely validated in more advanced-stage tumours.

15.
Endosc Int Open ; 8(8): E1052-E1060, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32743059

RESUMO

Background and study aims Delayed bleeding (DB) is the most frequent major adverse event after endoscopic mucosal resection (EMR) of large non-pedunculated colorectal polyps (LNPCPs). Evidence-based guidelines for management of DB are lacking. We aimed to evaluate the clinical presentation, treatment and outcome of patients with DB and to determine factors associated with hemostatic therapy. Patients and methods Patients with DB were identified by analyzing all consecutive EMR procedures for LNPCPs (≥ 2 cm) from one academic center (2012-2017) and seven regional hospitals (2015-2017). DB was defined as any postprocedural bleeding necessitating emergency department presentation, hospitalization or reintervention. Outcome of DB was assessed for three clinical scenarios: continued bleeding (CB), spontaneous resolution without recurrent bleeding during 24 hours observation (SR), and recurrent bleeding (RB). Variables associated with hemostatic therapy were analyzed using logistic regression. Results DB occurred after 42/542 (7.7 %) EMR procedures and re-colonoscopy was performed in 30 patients (72 %). Re-colonoscopy and hemostatic therapy rates were 92 % and 75 % for CB (n = 24), 25 % and 8 % for SR (n = 12), and 83 % and 67 % for RB (n = 6), respectively. Frequent hematochezia (≥ hourly) was the only factor significantly associated with hemostatic therapy (RR 2.23, p = 0.01). Re-bleeding after endoscopic hemostatic therapy occurred in 3/22 (13.6 %) patients. Conclusion Ongoing or recurrent hematochezia is associated with a high rate of hemostatic therapy, warranting re-colonoscopy in these patients. A conservative approach is justified when bleeding spontaneously settles, and without recurrent hematochezia during 24 hours observation patients can be safely discharged without endoscopic re-examination.

16.
United European Gastroenterol J ; : 2050640620975324, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33210982

RESUMO

BACKGROUND: Current risk stratification models for early invasive (T1) colorectal cancer are not able to discriminate accurately between prognostic favourable and unfavourable tumours, resulting in over-treatment of a large (>80%) proportion of T1 colorectal cancer patients. The tumour-stroma ratio (TSR), which is a measure for the relative amount of desmoplastic tumour stroma, is reported to be a strong independent prognostic factor in advanced-stage colorectal cancer, with a high stromal content being associated with worse prognosis and survival. We aimed to investigate whether the TSR predicts clinical outcome in patients with non-pedunculated T1 colorectal cancer. METHODS: Hematoxylin and eosin (H&E)-stained tumour tissue slides from a retrospective multi-centre case cohort of patients with non-pedunculated surgically treated T1 colorectal cancer were assessed for TSR by two independent observers who were blinded for clinical outcomes. The primary end point was adverse outcome, which was defined as the presence of lymph node metastasis in the resection specimen or colorectal cancer recurrence during follow-up. RESULTS: All 261 patients in the case cohort had H&E slides available for TSR scoring. Of these, 183 were scored as stroma-low, and 78 were scored as stroma-high. There was moderate inter-observer agreement (κ = 0.42). In total, 41 patients had lymph node metastasis, 17 patients had recurrent cancer and five had both. Stroma-high tumours were not associated with an increased risk for an adverse outcome (adjusted hazard ratio = 0.66, 95% confidence interval 0.37-1.18; p = 0.163). CONCLUSIONS: Our study emphasises that existing prognosticators may not be simply extrapolated to T1 colorectal cancers, even though their prognostic value has been widely validated in more advanced-stage tumours.

17.
FASEB J ; 21(7): 1492-502, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17317728

RESUMO

Spinal muscular atrophy is a neurodegenerative disease accompanied by a loss of motoneurons. Either mutations or deletions in the survival of motoneuron (SMN) gene are responsible for this defect. SMN is an assembly protein for RNA-protein complexes in the nucleus and is also found in axons of neurons. However, it is unclear which dysfunctions of SMN are important for disease progression. In this study we analyzed the contributions of different SMN regions for localization and neuronal differentiation associated with outgrowth of neurites. Suppression of endogenous SMN protein levels significantly decreased the growth of neurites. Down-regulation of the interacting protein gemin2 had the opposite effect. Surprisingly, selective overexpression of the SMN C-terminal domain promoted neurite outgrowth similar to full-length protein and could rescue the SMN knock-down effects. The knock-down led to a significant change in the G-/F-actin ratio, indicating a role for SMN in actin dynamics. Therefore, our data suggest a functional role for SMN in microfilament metabolism in axons of motoneurons.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Neuritos , Proteínas de Ligação a RNA/fisiologia , Actinas/metabolismo , Animais , Sequência de Bases , Compartimento Celular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/química , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Primers do DNA , Eletroforese em Gel de Poliacrilamida , Humanos , Imuno-Histoquímica , Microscopia de Fluorescência , Mutagênese , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Células PC12 , Ligação Proteica , RNA Interferente Pequeno , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ratos , Proteínas do Complexo SMN , Proteína 1 de Sobrevivência do Neurônio Motor
18.
Biomacromolecules ; 9(9): 2353-9, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18690740

RESUMO

Restorative medicine has a constant need for improved scaffold materials. Degradable biopolymers often suffer from uncontrolled chemical or enzymatic hydrolysis by the host. The need for a second surgery on the other hand is a major drawback for nondegradable scaffold materials. In this paper we report the design and synthesis of a novel polysialic acid-based hydrogel with promising properties. Hydrogel synthesis was optimized and enzymatic degradation was studied using a phage-born endosialidase. After addition of endosialidase, hydrogels readily degraded depending on the amount of initially used cross-linker within 2 to 11 days. This polysialic acid hydrogel is not cytotoxic, completely stable under physiological conditions, and could be evaluated as growth support for PC12 cells. Here, additional coating with collagen I, poly-L-lysine or matrigel is mandatory to improve the properties of the material.


Assuntos
Hidrogéis/síntese química , Hidrogéis/metabolismo , Neuraminidase/metabolismo , Ácidos Siálicos/metabolismo , Engenharia Tecidual/métodos , Animais , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Colágeno/química , Colágeno Tipo I/química , Combinação de Medicamentos , Eletroforese em Gel de Poliacrilamida , Hidrogéis/química , Hidrólise , Laminina/química , Conformação Molecular , Células PC12 , Polilisina/química , Proteoglicanas/química , Ratos
19.
CPT Pharmacometrics Syst Pharmacol ; 7(11): 759-770, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30207429

RESUMO

Alzheimer disease (AD) is a devastating neurodegenerative disorder with high unmet medical need. Drug development is hampered by limited understanding of the disease and its driving factors. Quantitative Systems Pharmacology (QSP) modeling provides a comprehensive quantitative framework to evaluate the relevance of biological mechanisms in the context of disease and to predict the efficacy of novel treatments. Here, we report a QSP model for AD with a particular focus on investigating the relevance of dysregulation of cholesterol and sphingolipids. We show that our model captures the modulation of several biomarkers in subjects with AD, as well as the response to pharmacological interventions. We evaluate the impact of targeting the sphingosine-1-phosphate 5 receptor (S1PR5) as a potential novel treatment option for AD, and model predictions increase our confidence in this novel disease pathway. Future applications for the QSP model are in validation of further targets and identification of potential treatment response biomarkers.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Esfingolipídeos/metabolismo , Idoso , Doença de Alzheimer/metabolismo , Animais , Estudos de Casos e Controles , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Ratos Sprague-Dawley , Ratos Wistar , Reprodutibilidade dos Testes
20.
Eur J Gastroenterol Hepatol ; 14(3): 243-8, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11953688

RESUMO

BACKGROUND: In ulcerative colitis the intestinal somatostatin content is reduced. Somatostatin has several immune-inhibitory effects. In vitro it diminishes activity of intestinal lymphocytes and peripheral blood monocytes. Its long-acting analogue octreotide has beneficial effects on mucosal damage in acute experimental acetic acid colitis in rats. AIMS: To determine the potential benefits of octreotide as a treatment for patients with severe ulcerative colitis treated with high dose corticosteroids. PATIENTS: Forty-two patients with severe ulcerative colitis (more than 10 points on the Powell-Tuck scoring system and mucosal disease Heatly grade III or IV). METHODS: In a multi-centre, double blind, placebo-controlled trial all patients were treated with oral 5-ASA (1.6-2.4 g daily) and high dose corticosteroids (tapering off from 60 to 80 mg daily). They were randomly assigned to receive subcutaneous placebo (n = 22) or octreotide 500 microg (n = 20) thrice daily during 21 days. Clinical and endoscopic disease activity, histology and laboratory parameters were obtained during the study period. RESULTS: Clinical disease activity for both octreotide and placebo were not significantly different at baseline and after 21 days of treatment. Endoscopic disease activities (mean +/- SD) changed from 12.5 +/- 4.7 to 7.2 +/- 5.3 for octreotide, and from 11.5 +/- 5.0 to 5.0 +/- 3.4 for placebo (NS). Seven patients from both groups received additional treatment (colectomy (n = 6), cyclosporin (n = 1)). Adverse events occurred equally in both groups. CONCLUSIONS: Subcutaneous administration of octreotide 500 microg thrice daily is not of additional benefit as adjuvant therapy to high dose corticosteroids in severe ulcerative colitis.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Fármacos Gastrointestinais/uso terapêutico , Glucocorticoides/uso terapêutico , Octreotida/uso terapêutico , Prednisolona/uso terapêutico , Prednisona/uso terapêutico , Adulto , Anti-Inflamatórios não Esteroides/uso terapêutico , Método Duplo-Cego , Esquema de Medicação , Feminino , Glucocorticoides/administração & dosagem , Humanos , Masculino , Mesalamina/uso terapêutico , Octreotida/administração & dosagem , Prednisolona/administração & dosagem , Prednisona/administração & dosagem , Índice de Gravidade de Doença
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