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1.
QJM ; 114(6): 381-389, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32589722

RESUMO

BACKGROUND: Perhaps, as never before, we need innovators. With our growing population numbers, and with increasing pressures on our education systems, are we in danger of becoming more rigid and formulaic and increasingly inhibiting innovation? When young can we predict who will become the great innovators? For example, in medicine, who will change clinical practice? AIMS: We therefore determined to assess whether the current academic excellence approach to medical school entrance would have captured previous great innovators in medicine, assuming that they should all have well fulfilled current entrance requirements. METHODS: The authors assembled a list of 100 great medical innovators which was then approved, rejected or added to by a jury of 12 MD fellows of the Royal Society of Canada. Two reviewers, who had taken both the past and present Medical College Admission Test as part of North American medical school entrance requirements, independently assessed each innovator's early life educational history in order to predict the innovator's likely success at medical school entry, assuming excellence in all entrance requirements. RESULTS: Thirty-one percent of the great medical innovators possessed no medical degree and 24% would likely be denied entry to medical school by today's standards (e.g. had a history of poor performance, failure, dropout or expulsion) with only 24% being guaranteed entry. Even if excellence in only one topic was required, the figure would only rise to 41% certain of medical school entry. CONCLUSION: These data show that today's medical school entry standards would have barred many great innovators and raise questions about whether we are losing medical innovators as a consequence. Our findings have important implications for promoting flexibility and innovation for medical education, and for promoting an environment for innovation in general.


Assuntos
Educação Médica , Humanos , Organizações
2.
Ann Oncol ; 32(1): 58-65, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33098992

RESUMO

BACKGROUND: In the TNT trial of triple negative breast cancer (NCT00532727), germline BRCA1/2 mutations were present in 28% of carboplatin responders. We assessed quantitative measures of structural chromosomal instability (CIN) to identify a wider patient subgroup within TNT with preferential benefit from carboplatin over docetaxel. PATIENTS AND METHODS: Copy number aberrations (CNAs) were established from 135 formalin-fixed paraffin-embedded primary carcinomas using Illumina OmniExpress SNP-arrays. Seven published [allelic imbalanced CNA (AiCNA); allelic balanced CNA (AbCNA); copy number neutral loss of heterozygosity (CnLOH); number of telomeric allelic imbalances (NtAI); BRCA1-like status; percentage of genome altered (PGA); homologous recombination deficiency (HRD) scores] and two novel [Shannon diversity index (SI); high-level amplifications (HLAMP)] CIN-measurements were derived. HLAMP was defined based on the presence of at least one of the top 5% amplified cytobands located on 1q, 8q and 10p. Continuous CIN-measurements were divided into tertiles. All nine CIN-measurements were used to analyse objective response rate (ORR) and progression-free survival (PFS). RESULTS: Patients with tumours without HLAMP had a numerically higher ORR and significantly longer PFS in the carboplatin (C) than in the docetaxel (D) arm [56% (C) versus 29% (D), PHLAMP,quiet = 0.085; PFS 6.1 months (C) versus 4.1 months (D), Pinteraction/HLAMP = 0.047]. In the carboplatin arm, patients with tumours showing intermediate telomeric NtAI and AiCNA had higher ORR [54% (C) versus 20% (D), PNtAI,intermediate = 0.03; 62% (C) versus 33% (D), PAiCNA,intermediate = 0.076]. Patients with high AiCNA and PGA had shorter PFS in the carboplatin arm [3.4 months (high) versus 5.7 months (low/intermediate); and 3.8 months (high) versus 5.6 months (low/intermediate), respectively; Pinteraction/AiCNA = 0.027, Padj.interaction/AiCNA = 0.125 and Pinteraction/PGA = 0.053, Padj.interaction/PGA = 0.176], whilst no difference was observed in the docetaxel arm. CONCLUSIONS: Patients with tumours lacking HLAMP and demonstrating intermediate CIN-measurements formed a subgroup benefitting from carboplatin relative to docetaxel treatment within the TNT trial. This suggests a complex and paradoxical relationship between the extent of genomic instability in primary tumours and treatment response in the metastatic setting.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de Mama Triplo Negativas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores , Carboplatina/uso terapêutico , Instabilidade Cromossômica/genética , Humanos , Fenótipo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética
3.
BMC Cancer ; 17(1): 784, 2017 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-29166865

RESUMO

The KHP PCaBB was established in 2013 and recruits donors from the Urology or Oncology Departments at Guy's Hospital in London (UK). Prostate cancer patients may be approached to give their consent for biobanking at any point in their treatment pathway, which allows residual material from their earlier diagnosis to be transferred and used by the Biobank. Currently, patients are specifically asked to donate samples of blood and surplus prostate tissue as well as permitting access to their clinical and pathological data that continues to be added throughout the course of their disease. Between 2013 and 2015, 549 prostate cancer patients gave their consent to the biobank and, the tissue repository collected 489 blood samples, 120 frozen prostate tissue samples and 1064 formalin fixed paraffin embedded diagnostic blocks.Prostate cancer has become a chronic disease in a large proportion of men, with many men receiving multiple subsequent treatments, and their treatment trajectory often spanning over decades. Therefore, this resource aims to provide an ideal research platform to explore potential variations in treatment response as well as disease markers in the different risk categories for prostate cancer.A recent audit of the KHP PCaBB revealed that between 2013 and 2015, 1796 patients were diagnosed with prostate cancer at King's Health Partners (KHP), out of which 549 (30.6%) gave their consent to KHP PCaBB. Comparisons between demographic and clinical characteristics of patients who had consented compared to the total patient population revealed that the KHP PCaBB is demographically representative of the total prostate cancer patient population seen in Guy's and St Thomas' NHS Foundation Trust (GSTT). We observed no differences in distribution of ethnicity (p = 0.507) and socioeconomic status (p = 0.097). Some differences were observed in clinical characteristics, specifically with treatment type - which differed significantly between the patients who had given consent and total patient population.The KHP PCaBB has thereby amassed a rich data and tissue repository that is largely reflective of both the demographic and clinical diversity within the total prostate cancer patient population seen at KHP, making it an ideal platform for prostate cancer research.


Assuntos
Bancos de Espécimes Biológicos , Neoplasias da Próstata , Adulto , Idoso , Idoso de 80 Anos ou mais , Pesquisa Biomédica , Humanos , Londres , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Bancos de Tecidos
4.
Acute Med ; 15(2): 51-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27441305

RESUMO

AIMS: To create a system to co-ordinate the medical take, bed management and track patient flow. To use the system to continuously audit against Society for Acute Medicine Quality Indicators. To use the data to model patient flow and optimise working patterns to improve waiting times. METHOD: An online whiteboard and underlying database system were designed, tested and implemented. Data from this system were used to audit against SAM Quality Indicators and then analysed to optimise both trainee and consultant working patterns. RESULTS: The online whiteboard proved effective and popular as a working tool. Data collection improved using the electronic system. Optimising junior doctor working patterns to match demand led to a reduction of average waiting time to see a doctor from 190 minutes to 71 minutes (p < 0.0001), and a reduction in the proportion of patients waiting over 4 hours from 40% to 10% (p > 0.0001). Optimising consultant working patterns did not produced significant changes in waiting times. CONCLUSIONS: The online whiteboard improved day-to-day working and data collection, when compared to the previous paper-based system. Better data facilitated analysis of working patterns leading to a significant improvement in patient waiting times.


Assuntos
Eficiência Organizacional , Serviços Médicos de Emergência/organização & administração , Serviço Hospitalar de Emergência/normas , Sistemas de Identificação de Pacientes , Gerenciamento do Tempo/métodos , Ocupação de Leitos/normas , Sistemas Computacionais , Humanos , Corpo Clínico Hospitalar/organização & administração , Sistemas de Identificação de Pacientes/métodos , Sistemas de Identificação de Pacientes/organização & administração , Admissão e Escalonamento de Pessoal/normas , Melhoria de Qualidade , Indicadores de Qualidade em Assistência à Saúde , Tempo para o Tratamento/normas , Reino Unido
5.
Oncogene ; 35(39): 5155-69, 2016 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-26996666

RESUMO

Cancer invasion is a hallmark of metastasis. The mesenchymal mode of cancer cell invasion is mediated by elongated membrane protrusions driven by the assembly of branched F-actin networks. How deregulation of actin regulators promotes cancer cell invasion is still enigmatic. We report that increased expression and membrane localization of the actin regulator Lamellipodin correlate with reduced metastasis-free survival and poor prognosis in breast cancer patients. In agreement, we find that Lamellipodin depletion reduced lung metastasis in an orthotopic mouse breast cancer model. Invasive 3D cancer cell migration as well as invadopodia formation and matrix degradation was impaired upon Lamellipodin depletion. Mechanistically, we show that Lamellipodin promotes invasive 3D cancer cell migration via both actin-elongating Ena/VASP proteins and the Scar/WAVE complex, which stimulates actin branching. In contrast, Lamellipodin interaction with Scar/WAVE but not with Ena/VASP is required for random 2D cell migration. We identified a phosphorylation-dependent mechanism that regulates selective recruitment of these effectors to Lamellipodin: Abl-mediated Lamellipodin phosphorylation promotes its association with both Scar/WAVE and Ena/VASP, whereas Src-dependent phosphorylation enhances binding to Scar/WAVE but not to Ena/VASP. Through these selective, regulated interactions Lamellipodin mediates directional sensing of epidermal growth factor (EGF) gradients and invasive 3D migration of breast cancer cells. Our findings imply that increased Lamellipodin levels enhance Ena/VASP and Scar/WAVE activities at the plasma membrane to promote 3D invasion and metastasis.


Assuntos
Proteínas de Transporte/genética , Proteínas de Ligação a DNA/genética , Neoplasias Mamárias Animais/genética , Proteínas de Membrana/genética , Família de Proteínas da Síndrome de Wiskott-Aldrich/genética , Citoesqueleto de Actina/genética , Animais , Moléculas de Adesão Celular/genética , Movimento Celular/genética , Fator de Crescimento Epidérmico/genética , Humanos , Neoplasias Mamárias Animais/patologia , Camundongos , Invasividade Neoplásica/genética , Fosforilação , Mapas de Interação de Proteínas/genética
6.
Eur J Cancer ; 50(10): 1697-1705, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24768572

RESUMO

INTRODUCTION: Predictors for site of distant metastasis and impact on survival in breast cancer are incompletely understood. METHODS: Clinico-pathological risk factors for site of distant metastasis and survival were analysed in patients with invasive breast cancer treated between 1986 and 2006. RESULTS: Of 3553 patients, with median follow-up 6.32years, 825 (23%) developed distant metastasis. The site of metastasis was bone in 196/825 (24%), viscera in 540/825 (65%) and unknown in 89 (11%). Larger primary invasive tumour size, higher tumour grade and axillary nodal positivity increased risk of metastasis to all sites. Lobular carcinoma was more likely to first metastasise to bone compared to invasive ductal carcinoma (NST). Oestrogen receptor (ER) negative, progesterone receptor (PgR) negative and/or Human epidermal growth factor (HER2) positive tumours were more likely to metastasise to viscera. A striking relationship between increasing age at diagnosis and a reduction in risk of distant metastasis to bone and viscera was observed. Median time to death from onset of metastatic disease was 1.52 (Interquartile range (IQR) 0.7-2.9)years for patients with bone metastasis and 0.7 (IQR 0.2-1.5)years for visceral metastasis. On multivariate analysis, despite the decrease in risk of distant metastasis with increasing age, there was an elevated hazard for death in patients >50years at diagnosis of metastasis if they developed bone metastasis, with a similar trend observed in the >70years age group if they developed visceral metastasis. CONCLUSION: These findings indicate that there are biological mechanisms underlying the impact of age on the development of distant metastasis and subsequent death. This may have important implications in the treatment of breast cancer.


Assuntos
Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/secundário , Carcinoma Lobular/secundário , Adulto , Fatores Etários , Idoso , Biomarcadores Tumorais/análise , Neoplasias Ósseas/química , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/terapia , Neoplasias da Mama/química , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/química , Carcinoma Ductal de Mama/mortalidade , Carcinoma Ductal de Mama/terapia , Carcinoma Lobular/química , Carcinoma Lobular/mortalidade , Carcinoma Lobular/terapia , Intervalo Livre de Doença , Receptores ErbB/análise , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Análise Multivariada , Gradação de Tumores , Invasividade Neoplásica , Modelos de Riscos Proporcionais , Estudos Prospectivos , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Sistema de Registros , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Carga Tumoral
7.
Oncogene ; 33(37): 4579-88, 2014 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-24662835

RESUMO

The antiestrogen tamoxifen is a well-tolerated, effective treatment for estrogen receptor-α-positive (ER+) breast cancer, but development of resistance eventually limits its use. Here we show that expression of MAGEA2, and related members of this cancer-testis antigen family, is upregulated in tamoxifen-resistant tumor cells. Expression of MAGEA2 in tumor lines grown in vitro or as xenografts led to continued proliferation in the presence of tamoxifen. At the molecular level, we demonstrate that MAGEA2 protein localizes to the nucleus and forms complexes with p53 and ERα, resulting in repression of the p53 pathway but increased ER-dependent signaling. In a series of ER+, tamoxifen-treated breast cancer patients, we show a highly significant (P=0.006) association between MAGEA (melanoma-associated antigen) expression and reduced overall survival, confirming the clinical significance of our observations.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Antígenos Específicos de Melanoma/metabolismo , Proteínas de Neoplasias/metabolismo , Tamoxifeno/química , Animais , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Antagonistas de Estrogênios/química , Receptor alfa de Estrogênio/metabolismo , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Células MCF-7 , Camundongos , Transplante de Neoplasias , Proteína Supressora de Tumor p53/metabolismo
8.
Breast Cancer Res Treat ; 144(2): 331-41, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24519386

RESUMO

The TACT trial is the largest study assessing the benefit of taxanes as part of adjuvant therapy for early breast cancer. The goal of this translational study was to clarify the predictive and prognostic value of Tau within the TACT trial. Tissue microarrays (TMA) were available from 3,610 patients. ER, PR, HER2 from the TACT trial and Tau protein expression was determined by immunohistochemistry on duplicate TMAs. Two parallel scoring systems were generated for Tau expression ('dichotomised' vs. 'combined' score). The positivity rate of Tau expression was 50 % in the trial population (n = 2,483). Tau expression correlated positively with ER (p < 0.001) and PR status (p < 0.001); but negatively with histological grade (p < 0.001) and HER2 status (p < 0.001). Analyses with either scoring systems for Tau expression demonstrated no significant interaction between Tau expression and efficacy of docetaxel. Contrary to the hypothesis that taxane benefit would be enriched in Tau negative/low patients, the only groups with a suggestion of a reduced event rate in the taxane group were the HER2-positive, Tau positive subgroups. Tau expression was seen to be a prognostic factor on univariate analysis associated with an improved DFS, independent of the treatment group (p < 0.001). It had no prognostic value in ER-negative tumours and the weak prognostic effect of Tau in ER-positive tumours (p = 0.02) diminished, when considering ER as an ordinal variable. On multivariable analyses, Tau had no prognostic value in either group. In addition, no significant interaction between Tau expression and benefit from docetaxel in patients within the PR-positive and negative subsets was seen. This is now the second large adjuvant study, and the first with quantitative analysis of ER and Tau expression, failing to show an association between Tau and taxane benefit with limited utility as a prognostic marker for Tau in ER-positive early breast cancer patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Proteínas tau/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Docetaxel , Epirubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Taxoides/administração & dosagem
9.
Br J Cancer ; 107(2): 221-3, 2012 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-22735901

RESUMO

BACKGROUND: The understanding of metastatic patterns after metachronous contralateral breast cancer (CBC) may help determine the biological nature of CBC. METHODS: A cohort of 8478 women with breast cancer treated at Guy's and St Thomas' NHS Foundation Trust between 1975 and 2006 were studied. Organ-specific 5-year cumulative incidence and incidence rate ratios were assessed for women diagnosed with unilateral breast cancer (UBC), CBC within 5 years and CBC more than 5 years of the initial diagnosis. RESULTS: Women diagnosed with CBC within 5 years had a higher incidence of metastases in all organs compared with UBC. Women with a short interval time to CBC developed metastasis more rapidly and were more likely to develop visceral and distant cutaneous metastases compared with bone metastasis. CONCLUSION: These findings explain poor prognosis of women with early occurring CBC and suggest that some of these CBCs are indicators of aggressive and/or systemic disease.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Segunda Neoplasia Primária/diagnóstico , Segunda Neoplasia Primária/patologia , Neoplasias da Mama/epidemiologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Incidência , Metástase Neoplásica , Segunda Neoplasia Primária/epidemiologia , Prognóstico , Reino Unido/epidemiologia
10.
Integr Biol (Camb) ; 3(6): 603-31, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21541433

RESUMO

We review novel, in vivo and tissue-based imaging technologies that monitor and optimize cancer therapeutics. Recent advances in cancer treatment centre around the development of targeted therapies and personalisation of treatment regimes to individual tumour characteristics. However, clinical outcomes have not improved as expected. Further development of the use of molecular imaging to predict or assess treatment response must address spatial heterogeneity of cancer within the body. A combination of different imaging modalities should be used to relate the effect of the drug to dosing regimen or effective drug concentration at the local site of action. Molecular imaging provides a functional and dynamic read-out of cancer therapeutics, from nanometre to whole body scale. At the whole body scale, an increase in the sensitivity and specificity of the imaging probe is required to localise (micro)metastatic foci and/or residual disease that are currently below the limit of detection. The use of image-guided endoscopic biopsy can produce tumour cells or tissues for nanoscopic analysis in a relatively patient-compliant manner, thereby linking clinical imaging to a more precise assessment of molecular mechanisms. This multimodality imaging approach (in combination with genetics/genomic information) could be used to bridge the gap between our knowledge of mechanisms underlying the processes of metastasis, tumour dormancy and routine clinical practice. Treatment regimes could therefore be individually tailored both at diagnosis and throughout treatment, through monitoring of drug pharmacodynamics providing an early read-out of response or resistance.


Assuntos
Biomarcadores Tumorais/análise , Imagem Molecular/métodos , Proteínas de Neoplasias/análise , Neoplasias/diagnóstico , Neoplasias/terapia , Humanos , Neoplasias/metabolismo , Integração de Sistemas
11.
Clin Exp Allergy ; 40(4): 582-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20067482

RESUMO

BACKGROUND: Leukotrienes play an important role in allergic and inflammatory diseases, but reports on the involvement of arachidonate 5-lipoxygenase-activating protein (ALOX5AP) and leukotriene A(4) hydrolase (LTA4H) in asthma have been inconclusive. OBJECTIVE: To determine whether polymorphisms in ALOX5AP and LTA4H genes are risk factors for asthma in two different Latino groups: Mexicans and Puerto Ricans. METHODS: The LTA4H gene was sequenced in individuals from both groups to identify novel polymorphisms. Single-nucleotide polymorphisms (SNPs) in the ALOX5AP and LTA4H genes were analysed for associations with asthma and asthma-related phenotypes in 687 parent-child trios of Mexican and Puerto Rican origin. RESULTS: In LTA4H, five previously unknown polymorphisms were identified. Two SNPs within LTA4H (rs17525488 and rs2540493) were protective for asthma in Latinos (P=0.007 and 0.05, respectively). Among the Mexican patients, LTA4H polymorphisms were associated with baseline lung function and IgE levels. For ALOX5AP, the minor allele at SNP rs10507391 was associated with protection from asthma (odds ratio=0.78, P=0.02) and baseline lung function (P=0.018) in Puerto Ricans. A gene-gene interaction was identified between LTA4H (rs17525488) and ALOX5AP (rs10507391), (P=0.003, in the combined sample). CONCLUSION: Our results support the role of LTA4H and ALOX5AP variants as risk factors for asthma in Latino populations.


Assuntos
Asma/genética , Proteínas de Transporte/genética , Epóxido Hidrolases/genética , Predisposição Genética para Doença , Hispânico ou Latino/genética , Proteínas de Membrana/genética , Proteínas Ativadoras de 5-Lipoxigenase , Adolescente , Alelos , Asma/etnologia , Asma/fisiopatologia , Proteínas de Transporte/metabolismo , Criança , Epóxido Hidrolases/metabolismo , Feminino , Frequência do Gene , Estudos de Associação Genética , Humanos , Masculino , Proteínas de Membrana/metabolismo , Americanos Mexicanos , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Adulto Jovem
12.
Br J Surg ; 96(4): 376-80, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19283743

RESUMO

BACKGROUND: The prognosis of patients with synchronous bilateral breast cancer (SBBC) is usually based on the tumour with the worst pathological features. There is little evidence in the literature for this assumption, potentially impairing reasoned decisions on optimal adjuvant therapy. METHODS: This was a case-control study in which 68 women with SBBC were matched with 128 women with unilateral breast cancer. Both the GuysRisk prognostic model and the Nottingham Prognostic Index were used to determine the bilateral tumour with the poorer prognosis. Controls were matched for age, menopausal status, date of diagnosis, histological type and grade, and oestrogen receptor and axillary node status. RESULTS: Both prognostic models indicated the same side tumour with the worst prognosis. Kaplan-Meier survival curves for both disease-free and overall survival showed no significant difference in outcome between the two groups. CONCLUSION: Prognosis was determined by the tumour with the worst prognosis, with no additional worsening of outcome incurred from the second tumour.


Assuntos
Neoplasias da Mama/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Estudos de Casos e Controles , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Mastectomia/mortalidade , Pessoa de Meia-Idade , Prognóstico , Carga Tumoral
13.
J Pathol ; 216(4): 408-17, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18937276

RESUMO

The aim of this study was to identify genes involved in the development of borderline and malignant phyllodes tumours of the breast (PTs). Expression profiling of 23 PTs (12 benign, 11 borderline/malignant) was performed using Affymetrix U133A GeneChips. mRNA expression in the borderline/malignant PTs was compared to the benign PTs. A group of 162 genes was over-expressed in the borderline/malignant group with a fold change > 2 and FDR < 0.1. Four of these genes were chosen for further investigation: PAX3, SIX1, TGFB2 and HMGA2. Over-expression was validated in a separate set of formalin-fixed, paraffin-embedded (FFPE) tumours, using either in situ hybridization or immunohistochemistry. This confirmed that expression of PAX3, SIX1, TGFB2 and HMGA2 in the stromal component of PTs was associated with the borderline/malignant phenotypes (p = 8.7 x 10(-5), p = 0.05, p = 0.009, p = 0.003, respectively; Fisher's exact test). The functional consequences of down-regulating these genes were studied using siRNA in short-term cultures and cell lines established from PTs. mRNA 'knock-down' of PAX3 resulted in significantly decreased cell proliferation in both a malignant and a borderline PT cell culture. mRNA 'knock-down' of SIX1 and HMGA2 resulted in decreased cell proliferation only in the malignant PT cell line, and 'knock-down' of TGFB2 resulted in decreased cell proliferation only in the borderline PT cell culture. This study shows that these four genes are involved in the development of borderline/malignant PTs. SIX1 over-expression was most marked in the highly malignant PTs, with particularly high expression in one case of metastatic PT. PAX3, TGFB2 and HMGA2 were expressed predominantly in borderline/malignant PTs, but showed some expression in benign tumours; they may be important in the transition from the benign to borderline/malignant phenotype.


Assuntos
Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Tumor Filoide/genética , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Imuno-Histoquímica , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/análise , RNA Interferente Pequeno/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Transfecção/métodos
15.
J Pathol ; 214(5): 533-44, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18288784

RESUMO

The aims of this study were to identify genetic changes associated with malignant progression of the fibroepithelial neoplasms, phyllodes tumours of the breast (PTs), and to ascertain whether genetic progression occurs when PTs recur locally. A further aim was to assess whether the genetic data support the classification of these tumours into three subtypes, benign, borderline and malignant. 126 PTs (37 benign, 41 borderline, 48 malignant) were analysed by either array-CGH or the Illumina Goldengate assay. The large-scale genetic changes associated with malignant/borderline phenotypes were +1q, +5p, +7, +8, -6, -9p, -10p and -13. Cluster analysis of the array-CGH data supported the division of malignant and borderline PTs into two separate groups, one comprising almost all malignant lesions and the other, benign and borderline tumours. Interstitial deletions of 9p21 that involved the p16INK4a locus were present in many malignant/borderline PTs, and some of these appeared to cause homozygous loss. Loss of expression of p16INK4a was found frequently and this was associated with 9p deletion; we also identified one p16INK4a mutation and evidence of methylation of p16INK4a in malignant PTs. Our evidence shows that inactivation of this gene is important in the development of malignant PTs. In selected PTs, multiple areas of stroma were isolated and analysed separately by array-CGH. We found considerable intra-tumoral genetic heterogeneity. Analysis of paired primary and recurrent tumours showed that recurrent tumours often acquired new genetic changes; in particular, benign tumours tended to acquire changes characteristic of the malignant/borderline phenotype. We believe it likely that unfavourable sub-clones not easily identified by histology account for the unpredictable clinical behaviour of these tumours.


Assuntos
Neoplasias da Mama/genética , Aberrações Cromossômicas , Recidiva Local de Neoplasia/genética , Tumor Filoide/genética , Neoplasias da Mama/patologia , Cromossomos Humanos Par 9/genética , Análise por Conglomerados , Metilação de DNA , DNA de Neoplasias/genética , Progressão da Doença , Feminino , Perfilação da Expressão Gênica/métodos , Genes p16 , Humanos , Mutação , Hibridização de Ácido Nucleico/métodos , Tumor Filoide/patologia , RNA Mensageiro/genética
16.
Oncogene ; 26(14): 2126-32, 2007 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-17016441

RESUMO

Basal-like breast cancers form a distinct subtype of breast cancer characterized by the expression of markers expressed in normal basal/myoepithelial cells. Breast cancers arising in carriers of germline BRCA1 mutations are predominately of basal-like type, suggesting that BRCA1 dysfunction may play a role in the pathogenesis of sporadic basal-like cancers. We analysed 37 sporadic breast cancers expressing the basal marker cytokeratin 5/6, and age- and grade-matched controls, for downregulation of BRCA1. Although BRCA1 promoter methylation was no more common in basal-like cancers (basal 14% vs controls 11%, P=0.72), BRCA1 messenger RNA expression was twofold lower in basal-like breast cancers compared to matched controls (P=0.008). ID4, a negative regulator of BRCA1, was expressed at 9.1-fold higher levels in basal-like breast cancer (P<0.0001), suggesting a potential mechanism of BRCA1 downregulation. BRCA1 downregulation correlated with the presence of multiple basal markers, revealing heterogeneity in the basal-like phenotype. Finally, we found that 63% of metaplastic breast cancers, a rare type of basal-like cancers, had BRCA1 methylation, in comparison to 12% of controls (P<0.0001). The high prevalence of BRCA1 dysfunction identified in this study could be exploited in the development of novel approaches to targeted treatment of basal-like breast cancer.


Assuntos
Proteína BRCA1/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Regulação Neoplásica da Expressão Gênica , Metilação de DNA , Regulação para Baixo , Feminino , Humanos , Queratina-5/análise , Queratina-6/análise , Regiões Promotoras Genéticas , RNA Mensageiro/análise , RNA Mensageiro/metabolismo
17.
Histopathology ; 49(1): 22-34, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16842243

RESUMO

AIMS: Cytokeratin (CK) 14, a myoepithelial marker, is also expressed in a proportion of breast carcinomas. There is evidence that these tumours show a differing metastatic pattern and clinical outcome from other invasive ductal carcinomas (IDCs) and may need different management. Currently, they are not identified in routine practice and no morphological guidelines exist to aid their identification. The aim of this study was to analyse the histological features of CK14+ IDC. METHODS AND RESULTS: A detailed histological review of 453 grade 3 IDCs revealed 88 (19.4%) that expressed CK14. Assessment was made independently by two pathologists using a standardized 'tick-box' proforma covering grade, architectural and cytological features. The results were analysed using logistic regression to identify features that predicted for basal phenotype. Concordance between the two pathologists was fair to good for most parameters (kappa 0.4-0.6). On multiple logistic regression, the basal phenotype was highly significantly associated with the presence of a central scar (P = 0.005), tumour necrosis (P < 0.0001), presence of spindle cells (P = 0.006) or squamous metaplasia (P < 0.0001), high total mitotic count (> 40 per 10 high-power field) (P = 0.0002) and high nuclear-cytoplasmic ratio (P = 0.0002). CONCLUSIONS: Specific morphological features are strongly associated with basal-like breast carcinoma. These could be used in routine diagnostic practice to identify this important subset of tumours.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/classificação , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/classificação , Carcinoma Ductal de Mama/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Queratina-14 , Queratinas/metabolismo , Neoplasia de Células Basais/classificação , Neoplasia de Células Basais/metabolismo , Neoplasia de Células Basais/patologia , Fenótipo
18.
Oncogene ; 25(49): 6544-53, 2006 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-16702952

RESUMO

We analysed chromosome 16q in 106 breast cancers using tiling-path array-comparative genomic hybridization (aCGH). About 80% of ductal cancers (IDCs) and all lobular cancers (ILCs) lost at least part of 16q. Grade I (GI) IDCs and ILCs often lost the whole chromosome arm. Grade II (GII) and grade III (GIII) IDCs showed less frequent whole-arm loss, but often had complex changes, typically small regions of gain together with larger regions of loss. The boundaries of gains/losses tended to cluster, common sites being 54.5-55.5 Mb and 57.4-58.8 Mb. Overall, the peak frequency of loss (83% cancers) occurred at 61.9-62.9 Mb. We also found several 'minimal' regions of loss/gain. However, no mutations in candidate genes (TRADD, CDH5, CDH8 and CDH11) were detected. Cluster analysis based on copy number changes identified a large group of cancers that had lost most of 16q, and two smaller groups (one with few changes, one with a tendency to show copy number gain). Although all morphological types occurred in each cluster group, IDCs (especially GII/GIII) were relatively overrepresented in the smaller groups. Cluster groups were not independently associated with survival. Use of tiling-path aCGH prompted re-evaluation of the hypothetical pathways of breast carcinogenesis. ILCs have the simplest changes on 16q and probably diverge from the IDC lineage close to the stage of 16q loss. Higher-grade IDCs probably develop from low-grade lesions in most cases, but there remains evidence that some GII/GIII IDCs arise without a GI precursor.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/genética , Cromossomos Humanos Par 16 , Invasividade Neoplásica/genética , Hibridização de Ácido Nucleico/métodos , Análise Serial de Tecidos/métodos , Aberrações Cromossômicas , Quebra Cromossômica , Análise por Conglomerados , DNA de Neoplasias , Amplificação de Genes , Deleção de Genes , Ligação Genética , Humanos , Perda de Heterozigosidade , Modelos Estatísticos , Estadiamento de Neoplasias
19.
Histopathology ; 48(6): 692-701, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16681685

RESUMO

AIM: Inflammation in carcinoma of the breast may represent an immune response to the tumour, but there is evidence that this response is impaired. Inflammation may also stimulate tumour growth by releasing proteolytic enzymes and angiogenic factors. Prognostic studies have produced conflicting results, but most investigators have not evaluated the different patterns of inflammation. The aim of this study was to test the hypothesis that moderate or marked diffuse inflammation is associated with a better prognosis. We also tested the 'danger model', which suggests that necrosis is necessary for an effective immune response. METHODS AND RESULTS: On multivariate analysis of women with stage 1 and 2 tumours (n = 679, median follow-up of 9.8 years), survival was independently associated with diffuse inflammation (relative risk 0.43, 95% confidence interval 0.24, 0.77, P =0.005) in addition to histological grade, axillary lymph node status, tumour size and oestrogen receptor status. The presence or absence of tumour necrosis did not have a clear effect on the relationship between survival and diffuse inflammation. CONCLUSIONS: Moderate or marked diffuse inflammation in breast cancer is associated with a better prognosis, suggesting that the immune effects of the inflammation predominate over the protumour effects.


Assuntos
Neoplasias da Mama/patologia , Mastite/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/química , Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/terapia , Humanos , Imuno-Histoquímica , Mastite/metabolismo , Pessoa de Meia-Idade , Análise Multivariada , Necrose , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Receptor ErbB-2/análise , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Análise de Sobrevida
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