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1.
Cancer ; 129(5): 697-713, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36572991

RESUMO

BACKGROUND: Cyclin E1 (CCNE1) is a potential predictive marker and therapeutic target in tubo-ovarian high-grade serous carcinoma (HGSC). Smaller studies have revealed unfavorable associations for CCNE1 amplification and CCNE1 overexpression with survival, but to date no large-scale, histotype-specific validation has been performed. The hypothesis was that high-level amplification of CCNE1 and CCNE1 overexpression, as well as a combination of the two, are linked to shorter overall survival in HGSC. METHODS: Within the Ovarian Tumor Tissue Analysis consortium, amplification status and protein level in 3029 HGSC cases and mRNA expression in 2419 samples were investigated. RESULTS: High-level amplification (>8 copies by chromogenic in situ hybridization) was found in 8.6% of HGSC and overexpression (>60% with at least 5% demonstrating strong intensity by immunohistochemistry) was found in 22.4%. CCNE1 high-level amplification and overexpression both were linked to shorter overall survival in multivariate survival analysis adjusted for age and stage, with hazard stratification by study (hazard ratio [HR], 1.26; 95% CI, 1.08-1.47, p = .034, and HR, 1.18; 95% CI, 1.05-1.32, p = .015, respectively). This was also true for cases with combined high-level amplification/overexpression (HR, 1.26; 95% CI, 1.09-1.47, p = .033). CCNE1 mRNA expression was not associated with overall survival (HR, 1.00 per 1-SD increase; 95% CI, 0.94-1.06; p = .58). CCNE1 high-level amplification is mutually exclusive with the presence of germline BRCA1/2 pathogenic variants and shows an inverse association to RB1 loss. CONCLUSION: This study provides large-scale validation that CCNE1 high-level amplification is associated with shorter survival, supporting its utility as a prognostic biomarker in HGSC.


Assuntos
Carcinoma , Cistadenocarcinoma Seroso , Neoplasias Ovarianas , Feminino , Humanos , Neoplasias Ovarianas/patologia , Fatores de Transcrição/genética , RNA Mensageiro , Cistadenocarcinoma Seroso/genética , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/uso terapêutico , Ciclina E/genética
2.
Virchows Arch ; 480(4): 855-871, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34782936

RESUMO

Tubo-ovarian high-grade serous carcinomas (HGSC) are highly proliferative neoplasms that generally respond well to platinum/taxane chemotherapy. We recently identified minichromosome maintenance complex component 3 (MCM3), which is involved in the initiation of DNA replication and proliferation, as a favorable prognostic marker in HGSC. Our objective was to further validate whether MCM3 mRNA expression and possibly MCM3 protein levels are associated with survival in patients with HGSC. MCM3 mRNA expression was measured using NanoString expression profiling on formalin-fixed and paraffin-embedded tissue (N = 2355 HGSC) and MCM3 protein expression was assessed by immunohistochemistry (N = 522 HGSC) and compared with Ki-67. Kaplan-Meier curves and the Cox proportional hazards model were used to estimate associations with survival. Among chemotherapy-naïve HGSC, higher MCM3 mRNA expression (one standard deviation increase in the score) was associated with longer overall survival (HR = 0.87, 95% CI 0.81-0.92, p < 0.0001, N = 1840) in multivariable analysis. MCM3 mRNA expression was highest in the HGSC C5.PRO molecular subtype, although no interaction was observed between MCM3, survival and molecular subtypes. MCM3 and Ki-67 protein levels were significantly lower after exposure to neoadjuvant chemotherapy compared to chemotherapy-naïve tumors: 37.0% versus 46.4% and 22.9% versus 34.2%, respectively. Among chemotherapy-naïve HGSC, high MCM3 protein levels were also associated with significantly longer disease-specific survival (HR = 0.52, 95% CI 0.36-0.74, p = 0.0003, N = 392) compared to cases with low MCM3 protein levels in multivariable analysis. MCM3 immunohistochemistry is a promising surrogate marker of proliferation in HGSC.


Assuntos
Cistadenocarcinoma Seroso , Componente 3 do Complexo de Manutenção de Minicromossomo , Neoplasias Ovarianas , Biomarcadores Tumorais/análise , Proliferação de Células , Cistadenocarcinoma Seroso/patologia , Feminino , Humanos , Antígeno Ki-67 , Componente 3 do Complexo de Manutenção de Minicromossomo/genética , Neoplasias Ovarianas/patologia , RNA Mensageiro , Taxa de Sobrevida
3.
BMC Med Educ ; 16(1): 311, 2016 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-27955651

RESUMO

BACKGROUND: Students in biomedical disciplines require understanding of normal and abnormal microscopic appearances of human tissues (histology and histopathology). For this purpose, practical classes in these disciplines typically use virtual microscopy, viewing digitised whole slide images in web browsers. To enhance engagement, tools have been developed to enable individual or collaborative annotation of whole slide images within web browsers. To date, there have been no studies that have critically compared the impact on learning of individual and collaborative annotations on whole slide images. METHODS: Junior and senior students engaged in Pathology practical classes within Medical Science and Medicine programs participated in cross-over trials of individual and collaborative annotation activities. Students' understanding of microscopic morphology was compared using timed online quizzes, while students' perceptions of learning were evaluated using an online questionnaire. RESULTS: For senior medical students, collaborative annotation of whole slide images was superior for understanding key microscopic features when compared to individual annotation; whilst being at least equivalent to individual annotation for junior medical science students. Across cohorts, students agreed that the annotation activities provided a user-friendly learning environment that met their flexible learning needs, improved efficiency, provided useful feedback, and helped them to set learning priorities. Importantly, these activities were also perceived to enhance motivation and improve understanding. CONCLUSION: Collaborative annotation improves understanding of microscopic morphology for students with sufficient background understanding of the discipline. These findings have implications for the deployment of annotation activities in biomedical curricula, and potentially for postgraduate training in Anatomical Pathology.


Assuntos
Educação de Pós-Graduação em Medicina , Histologia/educação , Microscopia/métodos , Patologia/educação , Estudantes de Medicina , Ensino , Instrução por Computador , Currículo , Avaliação Educacional , Humanos , Aprendizagem , Avaliação de Programas e Projetos de Saúde
4.
Arterioscler Thromb Vasc Biol ; 36(7): 1338-49, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27150391

RESUMO

OBJECTIVE: Cyclosporin A (CsA) is an immunosuppressant commonly used to prevent organ rejection but is associated with hyperlipidemia and an increased risk of cardiovascular disease. Although studies suggest that CsA-induced hyperlipidemia is mediated by inhibition of low-density lipoprotein receptor (LDLr)-mediated lipoprotein clearance, the data supporting this are inconclusive. We therefore sought to investigate the role of the LDLr in CsA-induced hyperlipidemia by using Ldlr-knockout mice (Ldlr(-/-)). APPROACH AND RESULTS: Ldlr(-/-) and wild-type (wt) C57Bl/6 mice were treated with 20 mg/kg per d CsA for 4 weeks. On a chow diet, CsA caused marked dyslipidemia in Ldlr(-/-) but not in wt mice. Hyperlipidemia was characterized by a prominent increase in plasma very low-density lipoprotein and intermediate-density lipoprotein/LDL with unchanged plasma high-density lipoprotein levels, thus mimicking the dyslipidemic profile observed in humans. Analysis of specific lipid species by liquid chromatography-tandem mass spectrometry suggested a predominant effect of CsA on increased very low-density lipoprotein-IDL/LDL lipoprotein number rather than composition. Mechanistic studies indicated that CsA did not alter hepatic lipoprotein production but did inhibit plasma clearance and hepatic uptake of [(14)C]cholesteryl oleate and glycerol tri[(3)H]oleate-double-labeled very low-density lipoprotein-like particles. Further studies showed that CsA inhibited plasma lipoprotein lipase activity and increased levels of apolipoprotein C-III and proprotein convertase subtilisin/kexin type 9. CONCLUSIONS: We demonstrate that CsA does not cause hyperlipidemia via direct effects on the LDLr. Rather, LDLr deficiency plays an important permissive role for CsA-induced hyperlipidemia, which is associated with abnormal lipoprotein clearance, decreased lipoprotein lipase activity, and increased levels of apolipoprotein C-III and proprotein convertase subtilisin/kexin type 9. Enhancing LDLr and lipoprotein lipase activity and decreasing apolipoprotein C-III and proprotein convertase subtilisin/kexin type 9 levels may therefore provide attractive treatment targets for patients with hyperlipidemia receiving CsA.


Assuntos
Ciclosporina , Hiperlipidemias/metabolismo , Metabolismo dos Lipídeos , Receptores de LDL/metabolismo , Animais , Apolipoproteína C-III/sangue , Biomarcadores/sangue , Ésteres do Colesterol/metabolismo , Modelos Animais de Doenças , Feminino , Predisposição Genética para Doença , Hiperlipidemias/sangue , Hiperlipidemias/induzido quimicamente , Hiperlipidemias/genética , Lipase Lipoproteica/sangue , Lipoproteínas HDL/sangue , Lipoproteínas IDL/sangue , Lipoproteínas VLDL/sangue , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Pró-Proteína Convertase 9/sangue , Receptores de LDL/deficiência , Receptores de LDL/genética , Fatores de Tempo , Trioleína/metabolismo
5.
Comput Inform Nurs ; 30(12): 672-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22872044

RESUMO

Diabetes is a global public health problem. Maintaining optimal glycemic control is critical for minimizing associated long-term complications and achieving better quality of life. Effective diabetes self-management education is one key component to enhance diabetes clients' self-management capabilities. The research team established a "Caring for Yourself-Managing Your Diabetes" Web site, which contained 35 video clips about diabetes management. The aim of this study was to evaluate user satisfaction with the Web-based diabetes self-management education program. A convenience sample of 100 diabetes clients (mean age, 61.5 [SD, 10.7] years) was invited to view one of the video clips via a laptop computer. A modified version of the Computer-Aided Learning Evaluation Questionnaire and the End-User Computing Satisfaction Questionnaire was used to evaluate participants' satisfaction with the program. The results indicate that participants were satisfied with the format, content, and accuracy of the Web-based diabetes education program. Some participants suggested adding different types of exercises that are specific to the needs of client groups and more explanation of diabetes medications. The results of this study support the use of computer-assisted learning as a promising method for delivering diabetes self-management education, which is satisfactory to diabetes clients.


Assuntos
Instrução por Computador , Diabetes Mellitus/terapia , Internet , Educação de Pacientes como Assunto/métodos , Satisfação do Paciente/estatística & dados numéricos , Autocuidado , Idoso , Estudos Transversais , Feminino , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Programas e Projetos de Saúde
7.
Cancer ; 99(6): 331-5, 2003 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-14681939

RESUMO

BACKGROUND: This study compared the findings of cervical cytology screening by ThinPrep Papanicolaou (Pap) tests (TP) with the findings of screening by conventional cervical smears (CS) in a screening population involving what to the authors' knowledge is the largest sample of ThinPrep Pap tests published to date. METHOD: Data from 191,581 CS that were screened in the period from March 1, 1998 to February 28, 2000 were compared with data from 190,667 TP performed from March 1, 2000 to February 28, 2002 and that were obtained from the same sources. RESULTS: With TP, the unsatisfactory rate was reduced from 0.48% to 0.32%. Fewer cases were considered to be suboptimal (19.12% vs. 12.97%). The detection rates of squamous cell carcinomas, adenocarcinomas, and high-grade squamous intraepithelial lesions (HSIL) were essentially unchanged in the TP group (0.005%, 0.003%, and 0.25%, respectively) compared with the rates for the CS group (0.01%, 0.006%, and 0.25%, respectively). There was an increase in the detection of atypical squamous cells of undetermined significance (ASCUS; 3.74% vs. 3.19%) and low-grade SIL (LSIL; 1.67% vs. 1.01%) with a decrease in the ASCUS-to-LSIL ratio from 3.15 for CS to 2.33 for TP. The detection of atypical glandular cells of undetermined significance (AGUS) increased slightly from 0.07% to 0.09%. The proportion of cells reported to have reactive atypia dropped from 2.71% to 1.48%. Limited biopsy correlation (range, 73.2-76.2%) confirmed the increased sensitivity of TP. More actinomyces (1.07% vs. 0.52%) were detected in TP samples despite of a similar portion of intrauterine-device users. The average primary screening and rapid rescreening time of each slide were reduced from 8 minutes to 4 minutes and from 2 minutes to less than 1 minute, respectively. CONCLUSIONS: The preliminary experience of the authors of the current study appears to support the use of the ThinPrep Pap test to enhance the efficiency of cervical cytology screening.


Assuntos
Adenocarcinoma/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Programas de Rastreamento , Teste de Papanicolaou , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Esfregaço Vaginal/métodos , Adenocarcinoma/patologia , Adulto , Ásia , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Microtomia , Estudos Retrospectivos , Sensibilidade e Especificidade , Manejo de Espécimes , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/patologia
8.
Mol Cell Biol ; 23(9): 3253-64, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12697825

RESUMO

The high-mobility-group (HMG) box is a conserved DNA-binding domain found in a family of transcription factors that regulate growth and development. One family member, Ste11p, directs sexual differentiation of Schizosaccharomyces pombe by binding specific DNA sequences upstream of genes required for mating and meiosis. Here, we show that Ste11p is a shuttling protein. In growing cells, Ste11p is present in low levels and is pancellular. Mating pheromones and nutrient limitation trigger nuclear accumulation and increased expression of the transcription factor. Several mechanisms likely control Ste11p localization. First, the 14-3-3 protein, Rad24p, binds phosphorylated Ste11p and inhibits its nuclear accumulation. Second, the HMG domain of Ste11p contains a basic cluster nuclear localization signal. Finally, treatment of cells with leptomycin B, an exportin inhibitor, results in the nuclear accumulation of Ste11p. A Ste11p deletion mutation, DeltaC54, mimics the effects of leptomycin B. The C54 region contains no identifiable nuclear export signal but instead is required for biological activity and to stimulate Ste11p target gene expression. These results provide evidence that both nuclear import and export mechanisms operate to regulate cellular localization of an HMG box protein. In addition, they establish a paradigm for the potential role of pheromone/hormone-like polypeptides in cellular localization of this important class of developmental regulators.


Assuntos
Núcleo Celular/metabolismo , Citoplasma/metabolismo , Feromônios/metabolismo , Receptores Citoplasmáticos e Nucleares , Proteínas de Schizosaccharomyces pombe/metabolismo , Fatores de Transcrição/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Conjugação Genética , Meios de Cultura , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas Fúngicas , Regulação Fúngica da Expressão Gênica , Proteínas de Fluorescência Verde , Domínios HMG-Box , Peptídeos e Proteínas de Sinalização Intracelular , Carioferinas/genética , Carioferinas/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Nitrogênio/metabolismo , Sinais de Localização Nuclear , Proteínas de Ligação a RNA , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Proteínas de Schizosaccharomyces pombe/genética , Deleção de Sequência , Fatores de Transcrição/genética , Proteína Exportina 1
9.
Curr Genet ; 43(3): 178-85, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12664134

RESUMO

Ran1/Pat1 kinase and cAMP-dependent protein kinase (PKA) regulate sexual differentiation in Schizosaccharomyces pombe. A reduction in the activity of both enzymes is a prerequisite for meiosis. Together, PKA and Pat1 control the level of expression of the Mei2 RNA-binding protein. Pat1 further regulates the activity of Mei2 by phosphorylation. Phosphorylation inactivates Mei2 by interfering with its cellular localization and by causing degradation of the protein via the ubiquitin-proteasome pathway. The inhibitor of Pat1, Mei3, is found only in diploid cells undergoing meiosis. Expression of mei3 is sufficient to induce meiosis. Here, we examine the relationship between Pat1, PKA and Mei3. We demonstrate that Mei3 is an in vitro substrate for PKA. Using site-specific mutagenesis, the major PKA phosphorylation site is identified. In vivo assays indicate that phosphorylation of Mei3 by PKA does not significantly alter the ability of the inhibitor to regulate Pat1. Although it does not function as an inhibitor for PKA, ectopic expression of Mei3 causes cells containing high PKA levels to undergo meiosis. Expression of various mei3 alleles in cells containing unregulated PKA activity shows that the ability to undergo meiosis correlates with Pat1 activity. Notably, induced levels of mei2 are not a prerequisite for meiotic differentiation, as previously thought. The implications of this result to developmental regulation are discussed.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/genética , Inativação Gênica , Meiose/genética , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases , Proteínas de Ligação a RNA/genética , Proteínas de Schizosaccharomyces pombe/genética , Mutagênese Sítio-Dirigida , Oligonucleotídeos , Fosforilação , Inibidores de Proteínas Quinases , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Schizosaccharomyces
10.
Clin Endocrinol (Oxf) ; 56(3): 397-403, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11940053

RESUMO

OBJECTIVES: Galanin (GAL) is a neuropeptide widely expressed in the central and peripheral nervous system and in neuroendocrine tissue, including the adenohypophysis where, in humans, it is expressed in corticotrophs and in ACTH-producing adenomas. Previous analyses of human tissue have used antiserum against porcine GAL for detection of GAL immunoreactivity (GAL-IR) and no pathophysiological correlates have been reported. Given significant differences between the sequence of porcine and human GAL peptides, the aim of this study was to use antiserum raised against synthetic human GAL to investigate GAL-IR in non tumorous pituitaries and in pituitary adenomas, and to correlate GAL-IR with the clinical and hormonal characteristics of patients with Cushing's disease. PATIENTS: Six nontumorous pituitaries were obtained from autopsy and 151 pituitary adenomas, comprising 62 functioning (16 corticotroph, 26 somatotroph, 19 lactotroph and one thyrotroph) and 89 nonfunctioning adenomas, were obtained by surgery. RESULTS: All non tumorous pituitary glands showed GAL-IR in corticotrophs, in basophil cells within the neurohypophysis and in nerve fibres of the neurohypophysis. GAL-IR was found in a subset (10 of 16) of patients with ACTH-secreting tumours causing Cushing's syndrome. GAL-IR was rarely expressed in somatotroph adenomas and prolactinomas, but was expressed in approximately one-third of nonfunctioning tumours. GAL-IR was found in almost 90% of nonfunctioning tumours that were positive for ACTH. There were no significant differences in sex ratio, age at presentation or 24-h urinary free cortisol secretion in the subset of patients with Cushing's disease positive (n = 10) or negative (n = 6) for GAL-IR. However, Cushing's patients positive for GAL-IR tended to have smaller tumours and achieved a higher cure rate than those without (100 vs. 50%, P = 0.017). CONCLUSIONS: Galanin is present in normal and tumorous human pituitaries. In addition, GAL colocalizes exclusively in corticotrophs of normal pituitaries and is coexpressed almost exclusively in corticotrophs from functioning and nonfunctioning tumours. The finding that corticotroph adenomas can function irrespective of the presence of GAL suggests that GAL may not play a pathophysiological role in Cushing's disease. However, the better surgical outcome observed in patients with Cushing's disease who had tumours positive for GAL-IR suggests that the expression of GAL confers a less aggressive tumour phenotype.


Assuntos
Adenoma/química , Biomarcadores Tumorais/análise , Galanina/análise , Hipófise/química , Neoplasias Hipofisárias/química , Adenoma/complicações , Adenoma/cirurgia , Hormônio Adrenocorticotrópico/análise , Adulto , Síndrome de Cushing/etiologia , Síndrome de Cushing/metabolismo , Síndrome de Cushing/cirurgia , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/cirurgia , Prognóstico
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