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1.
Gastric Cancer ; 25(1): 107-123, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34554347

RESUMO

BACKGROUND: Gastric adenocarcinoma is common and consequent mortality high. Presentation and mortality are increased in obese individuals, many of whom have elevated circulating insulin concentrations. High plasma insulin concentrations may promote, and increase mortality from, gastric adenocarcinoma. Tumour promotion activities of insulin and its receptor are untested in gastric cancer cells. METHODS: Tumour gene amplification and expression were computed from sequencing and microarray data. Associations with patient survival were assessed. Insulin-dependent signal transduction, growth, apoptosis and anoikis were analysed in metastatic cells from gastric adenocarcinoma patients and in cell lines. Receptor involvement was tested by pharmacological inhibition and genetic knockdown. RNA was analysed by RT-PCR and proteins by western transfer and immunofluorescence. RESULTS: INSR expression was higher in tumour than in normal gastric tissue. High tumour expression was associated with worse patient survival. Insulin receptor was detected readily in metastatic gastric adenocarcinoma cells and cell lines. Isoforms B and A were expressed. Pharmacological inhibition prevented cell growth and division, and induced caspase-dependent cell death. Rare tumour INS expression indicated tumours would be responsive to pancreatic or therapeutic insulins. Insulin stimulated gastric adenocarcinoma cell PI3-kinase/Akt signal transduction, proliferation, and survival. Insulin receptor knockdown inhibited proliferation and induced programmed cell death. Type I IGF receptor knockdown did not induce cell death. CONCLUSIONS: The insulin and IGF signal transduction pathway is dominant in gastric adenocarcinoma. Gastric adenocarcinoma cell survival depends upon insulin receptor. That insulin has direct cancer-promoting effects on tumour cells has implications for clinical management of obese and diabetic cancer patients.


Assuntos
Insulina , Receptor de Insulina , Neoplasias Gástricas , Linhagem Celular Tumoral , Humanos , Insulina/metabolismo , Fator de Crescimento Insulin-Like I/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Receptor de Insulina/genética , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
2.
BMJ Open Qual ; 10(4)2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34686487

RESUMO

The Welsh Transplantation and Immunogenetics Laboratory (WTAIL) is responsible for managing patient work-up for haematopoietic stem cell transplantation (HSCT), the only potentially curative option for many haematological and non-haematological conditions. Work-up requires regular communication between WTAIL and the transplanting clinicians, facilitated by weekly multidisciplinary team (MDT) meetings, to agree decisions and proceed through each work-up stage. Effective communication and minimising error are critical, as transplanting cells from a suboptimal donor could have severe or fatal consequences for the patient. We reviewed our HSCT patient management and identified issues including staff dissatisfaction with the inefficiency of the current (paper-based) system and concern about the potential for incidents caused by errors in manual transcription of patient information and tracking clinical decisions. Another driver for change was the COVID-19 pandemic, which prevented the usual face-to-face MDT meetings in which staff would show clinicians the paper records and reports; the shift to online MDT required new ways of sharing data. In this project we developed a new central reference point for our patient management data along with electronic patient summary sheets, designed with an eye to improving safety and efficiency. Over several improvement cycles we tested and refined the summary sheets with staff and clinicians and experimented with videoconferencing to facilitate data sharing. We conducted interviews with staff from which we concluded that the new process successfully reduced transcription and duplication and improved communication with the clinicians during the pandemic. Despite an increase in workload due to build-up of active patient work-up cases during the pandemic, staff reported that the new summaries enabled them to cope well. A key initiative was creation of a 'Task and Finish' group that helped establish continual improvement culture and identified additional areas for improvement which have been followed up in further improvement projects.


Assuntos
COVID-19 , Transplante de Células-Tronco Hematopoéticas , Humanos , Gestão da Informação , Pandemias , SARS-CoV-2
3.
Women Health ; 61(9): 867-871, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34569446

RESUMO

Metastatic spread of invasive lobular breast carcinoma to stomach is rare especially before diagnosis of primary breast cancer. Incorrect diagnosis might result in delay of appropriate treatment for breast cancer. Recognition of this possibility enables better clinical management. A 62-year-old female presented with upper gastrointestinal symptoms and weight loss and was referred to a gastroenterologist for investigation. At the time of initial diagnosis of stomach cancer, patient was asymptomatic for breast cancer. Multiple gastric biopsies taken showed features suspicious of metastatic breast cancer. Consequently, the initial provisional diagnosis of stomach cancer changed into metastatic invasive lobular breast carcinoma. These findings were corroborated radiologically. The patient was treated with letrozole and zoledronic acid as first-line therapy for one year. Residual metastatic breast cancer was present in the gastric mucosa. The patient was treated with endocrine therapy containing ribociclib and treatment was ineffective confirmed by PET-CT scan. But her symptoms have resolved completely despite her presentation with stage IV. We present rare case of initial presentation of gastric metastasis before diagnosis of a primary invasive lobular breast carcinoma. Correct diagnosis and appropriate treatment were accomplished through initial clinical suspicion, accurate histological examination, and endoscopy together with analysis of disease-specific biomarkers.


Assuntos
Neoplasias da Mama , Carcinoma Lobular , Neoplasias da Mama/diagnóstico , Carcinoma Lobular/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Paquistão , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estômago
4.
Transplant Rev (Orlando) ; 35(2): 100596, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33582579

RESUMO

Sensitisation to human leukocyte antigen (HLA) represents a significant barrier to kidney transplantation. Antibody removal and immune modulation strategies, known as 'desensitisation', aim to reduce levels of circulating HLA antibodies and increase transplant opportunities for highly sensitised patients (HSPs). However, the effects of desensitisation are generally transient and maintaining low or absent HLA antibody levels remains a substantial challenge. Furthermore, several studies report variation in patient response, with a proportion of desensitised patients able to replenish or maintain levels of circulating HLA specific antibodies despite receiving treatment to remove antibodies, antibody-producing plasma cells and their precursor B-cells. Various factors that influence the response to desensitisation have been proposed. However, the immune system is central, with differences in cytokine and leukocyte repertoire (i.e. the persistence of HLA antibody producing long-lived plasma cells (LLPCs) residing in the bone marrow) critical to desensitisation. Various cytokines are involved in commitment of B-cells to the LLPC fate, including interleukin (IL)-6, IL-21, B-cell activation factor (BAFF), a proliferation-inducing ligand (APRIL) and C-X-C motif chemokine 12 (CXCL12). Several studies have investigated variation in patient response to desensitisation with various immunological factors proposed as predictive biomarkers. However, this review reveals a need for larger studies to validate existing findings and a need for better understanding of the complex effects of desensitisation on immune profiles.


Assuntos
Transplante de Rim , Anticorpos , Antígenos HLA , Humanos
5.
Int J Mol Sci ; 20(18)2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31500233

RESUMO

Helicobacter pylori colonises the human stomach and has tropism for the gastric mucin, MUC5AC. The majority of organisms live in the adherent mucus layer within their preferred location, close to the epithelial surface where the pH is near neutral. Trefoil factor 1 (TFF1) is a small trefoil protein co-expressed with the gastric mucin MUC5AC in surface foveolar cells and co-secreted with MUC5AC into gastric mucus. Helicobacter pylori binds with greater avidity to TFF1 dimer, which is present in gastric mucus, than to TFF1 monomer. Binding of H. pylori to TFF1 is mediated by the core oligosaccharide subunit of H. pylori lipopolysaccharide at pH 5.0-6.0. Treatment of H. pylori lipopolysaccharide with mannosidase or glucosidase inhibits its interaction with TFF1. Both TFF1 and H. pylori have a propensity for binding to mucins with terminal non-reducing α- or ß-linked N-acetyl-d-glucosamine or α-(2,3) linked sialic acid or Gal-3-SO42-. These findings are strong evidence that TFF1 has carbohydrate-binding properties that may involve a conserved patch of aromatic hydrophobic residues on the surface of its trefoil domain. The pH-dependent lectin properties of TFF1 may serve to locate H. pylori deep in the gastric mucus layer close to the epithelium rather than at the epithelial surface. This restricted localisation could limit the interaction of H. pylori with epithelial cells and the subsequent host signalling events that promote inflammation.


Assuntos
Helicobacter pylori/fisiologia , Lipopolissacarídeos/metabolismo , Estômago/microbiologia , Fator Trefoil-1/metabolismo , Mucinas Gástricas/metabolismo , Glucosidases/farmacologia , Helicobacter pylori/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Lipopolissacarídeos/química , Manosidases/farmacologia , Mucina-5AC/metabolismo , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/metabolismo , Ligação Proteica/efeitos dos fármacos , Multimerização Proteica , Fator Trefoil-1/química , Tropismo
6.
Microorganisms ; 6(2)2018 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-29783620

RESUMO

Helicobacter pylori binds to the gastric mucin, MUC5AC, and to trefoil factor, TFF1, which has been shown to interact with gastric mucin. We examined the interactions of TFF1 and H. pylori with purified gastrointestinal mucins from different animal species and from humans printed on a microarray platform to investigate whether TFF1 may play a role in locating H. pylori in gastric mucus. TFF1 bound almost exclusively to human gastric mucins and did not interact with human colonic mucins. There was a strong correlation between binding of TFF1 and H. pylori to human gastric mucins, and between binding of both TFF1 and H. pylori to gastric mucins with that of Griffonia simplicifolia lectin-II, which is specific for terminal non-reducing α- or ß-linked N-acetyl-d-glucosamine. These results suggest that TFF1 may help to locate H. pylori in a discrete layer of gastric mucus and hence restrain their interactions with epithelial cells.

7.
Oncotarget ; 7(34): 54445-54462, 2016 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-27437872

RESUMO

Amplification of seven oncogenes: HER2, EGFR, FGFR1, FGFR2, MET, KRAS and IGF1R has been identified in gastric cancer. The first five are targeted therapeutically in patients with HER2-positivity, FGFR2- or MET-amplification but the majority of patients are triple-negative and require alternative strategies. Our aim was to evaluate the importance of the IGF1R tyrosine kinase in triple-negative gastric cancer with and without oncogenic KRAS, BRAF or PI3K3CA mutations. Cell lines and metastatic tumor cells isolated from patients expressed IGF1R, and insulin-like growth factor-1 (IGF-1) activated the PI3-kinase/Akt and Ras/Raf/MAP-kinase pathways. IGF-1 protected triple-negative cells from caspase-dependent apoptosis and anoikis. Protection was mediated via the PI3-kinase/Akt pathway. Remarkably, IGF-1-dependent cell survival was greater in patient samples. IGF-1 stimulated triple-negative gastric cancer cell growth was prevented by IGF1R knockdown and Ras/Raf/MAP-kinase pathway inhibition. The importance of the receptor in cell line and metastatic tumor cell growth in serum-containing medium was demonstrated by knockdown and pharmacological inhibition with figitumumab. The proportions of cells in S-phase and mitotic-phase, and Ras/Raf/MAP-kinase pathway activity, were reduced concomitantly. KRAS-addicted and BRAF-impaired gastric cancer cells were particularly susceptible. In conclusion, IGF1R and the IGF signal transduction pathway merit consideration as potential therapeutic targets in patients with triple-negative gastric cancer.


Assuntos
Proteínas Proto-Oncogênicas c-met/genética , Receptor ErbB-2/análise , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptores de Somatomedina/fisiologia , Neoplasias Gástricas/patologia , Proteínas ras/fisiologia , Linhagem Celular Tumoral , Proliferação de Células , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Amplificação de Genes , Humanos , Mutação , Fosforilação , Proteínas Proto-Oncogênicas B-raf/fisiologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Receptor IGF Tipo 1 , Transdução de Sinais/fisiologia , Neoplasias Gástricas/química
8.
Mol Cell Oncol ; 3(1): e1010950, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27308527

RESUMO

The MYC (v-myc avian myelocytomatosis viral oncogene homolog; c-MYC) locus on chromosome 8q is susceptible to high-level amplification following exposure of human breast cells to ionizing radiation, and c-MYC amplification is a common feature of both radiogenic adenocarcinoma and radiogenic angiosarcoma of the breast. Taken together, these observations suggest common breast-specific susceptibility factors that predispose cells to amplification of this critical proto-oncogene and the development of radiogenic cancer in multiple tissue types of this radiosensitive organ.

9.
Mol Cancer ; 15: 8, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26801096

RESUMO

BACKGROUND: Detachment of epithelial cells from the extracellular matrix initiates programmed cell death by a process termed anoikis. Malignant cells must acquire anoikis resistance to leave the primary tumour and metastasise. Multiple signal transduction pathways can activate anoikis and confer anoikis resistance, but these are not understood in breast cancer. METHODS: Models for anoikis of oestrogen-responsive breast cancer cells were established and the protective effects of IGF-1 tested. Cleaved PARP was measured by western transfer and cleaved caspase 3 by flow cytometry. Pathways involved in anoikis and in anoikis resistance were investigated with PI3-kinase, Akt, and MEK1 and MEK2 inhibitors. The importance of the type I IGF receptor was investigated by IGF-concentration dependence, siRNA knockdown and pharmacological inhibition. Association between IGF-1R expression and relapse with distant metastasis was analysed in 1609 patients by log rank test. RESULTS: Unattached breast cancer cells required culture in serum-free medium to induce anoikis. Rapid loss of FAK, Akt and Bad phosphorylation was concurrent with anoiks induction, but ERK1 and ERK2 phosphorylation increased which suggested that anoikis resistance is mediated by the PI3-kinase/Akt rather than the Grb2/Ras/MAP-kinase pathway. IGF-1 conferred anoikis resistance in serum-free medium. IGF-1 activated the PI3-kinase/Akt and Grb2/Ras/MAP-kinase pathways but experiments with PI3-kinase, Akt and MEK1 and MEK2 inhibitors showed that IGF protection is via the PI3-kinase/Akt pathway. The concentration dependence of IGF protection, knockdown experiments with siRNA and pharmacological inhibition with figitumumab, showed that IGF-1 signals through the type I IGF receptor. The crucial role of the type I IGF receptor was demonstrated by induction of anoikis in full serum by figitumumab. High IGF-1R expression was associated with reduced time to relapse with distant metastases in oestrogen receptor-positive patients, especially those with aggressive disease which confirms its relevance in vivo. CONCLUSIONS: Anoikis resistance of oestrogen-responsive breast cancer cells depends upon IGF activation of the type I IGF receptor and PI3-kinase/Akt pathway. Because IGF-dependent evasion of anoikis will facilitate metastasis by malignant breast cancer cells, effective inhibition of IGF signal transduction should be included in combinations of targeted drugs designed to treat metastatic oestrogen receptor-positive breast cancers.


Assuntos
Anoikis/efeitos dos fármacos , Neoplasias da Mama/patologia , Estrogênios/farmacologia , Fator de Crescimento Insulin-Like I/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Caspases/metabolismo , Adesão Celular/efeitos dos fármacos , Intervalo Livre de Doença , Feminino , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células MCF-7
10.
Int J Cancer ; 138(1): 206-16, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26178530

RESUMO

Interest has increased in the potential role of circulating tumour cells in cancer management. Most cell-based studies have been designed to determine the number of circulating tumour cells in a given volume of blood. Ability to understand the biology of the cancer cells would increase the clinical potential. The purpose of this study was to develop and validate a novel, widely applicable method for detection and characterisation of circulating tumour cells. Cells were imaged with an ImageStream(X) imaging flow cytometer which allows detection of expression of multiple biomarkers on each cell and produces high-resolution images. Depletion of haematopoietic cells was by red cell lysis, leukocyte common antigen CD45 depletion and differential centrifugation. Expression of epithelial cell adhesion molecule, cytokeratins, tumour-type-specific biomarkers and CD45 was detected by immunofluorescence. Nuclei were identified with DAPI or DRAQ5 and brightfield images of cells were collected. The method is notable for the dearth of cell damage, recoveries greater than 50%, speed and absence of reliance on the expression of a single biomarker by the tumour cells. The high-quality images obtained ensure confidence in the specificity of the method. Validation of the methodology on samples from patients with oesophageal, hepatocellular, thyroid and ovarian cancers confirms its utility and specificity. Importantly, this adaptable method is applicable to all tumour types including those of nonepithelial origin. The ability to measure simultaneously the expression of multiple biomarkers will facilitate analysis of the cancer cell biology of individual circulating tumour cells.


Assuntos
Citometria de Fluxo/métodos , Neoplasias Hepáticas/diagnóstico , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patologia , Neoplasias Ovarianas/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Superfície/metabolismo , Biomarcadores Tumorais/metabolismo , Feminino , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias
11.
Oncotarget ; 6(32): 32396-409, 2015 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-26486089

RESUMO

ATR is an attractive target in cancer therapy because it signals replication stress and DNA lesions for repair and to S/G2 checkpoints. Cancer-specific defects in the DNA damage response (DDR) may render cancer cells vulnerable to ATR inhibition alone. We determined the cytotoxicity of the ATR inhibitor VE-821 in isogenically matched cells with DDR imbalance. Cell cycle arrest, DNA damage accumulation and repair were determined following VE-821 exposure.Defects in homologous recombination repair (HRR: ATM, BRCA2 and XRCC3) and base excision repair (BER: XRCC1) conferred sensitivity to VE-821. Surprisingly, the loss of different components of the trimeric non-homologous end-joining (NHEJ) protein DNA-PK had opposing effects. Loss of the DNA-binding component, Ku80, caused hypersensitivity to VE-821, but loss of its partner catalytic subunit, DNA-PKcs, did not. Unexpectedly, VE-821 was particularly cytotoxic to human and hamster cells expressing high levels of DNA-PKcs. High DNA-PKcs was associated with replicative stress and activation of the DDR. VE-821 suppressed HRR, determined by RAD51 focus formation, to a greater extent in cells with high DNA-PKcs.Defects in HRR and BER and high DNA-PKcs expression, that are common in cancer, confer sensitivity to ATR inhibitor monotherapy and may be developed as predictive biomarkers for personalised medicine.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Dano ao DNA , Reparo do DNA , Glioblastoma/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Pirazinas/farmacologia , Sulfonas/farmacologia , Animais , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Células CHO , Linhagem Celular Tumoral , Biologia Computacional , Cricetinae , Cricetulus , Reparo do DNA/genética , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Proteína Quinase Ativada por DNA/genética , Proteína Quinase Ativada por DNA/metabolismo , Bases de Dados Genéticas , Relação Dose-Resposta a Droga , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Perfilação da Expressão Gênica/métodos , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glioblastoma/enzimologia , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Terapia de Alvo Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção
12.
Endocr Relat Cancer ; 22(3): 465-79, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25900183

RESUMO

The stratification of breast cancer patients for endocrine therapies by oestrogen or progesterone receptor expression is effective but imperfect. The present study aims were to validate microarray studies that demonstrate TFF3 regulation by oestrogen and its association with oestrogen receptors in breast cancer, to evaluate TFF3 as a biomarker of endocrine response, and to investigate TFF3 function. Microarray data were validated by quantitative RT-PCR and northern and western transfer analyses. TFF3 was induced by oestrogen, and its induction was inhibited by antioestrogens, tamoxifen, 4-hydroxytamoxifen and fulvestrant in oestrogen-responsive breast cancer cells. The expression of TFF3 mRNA was associated with oestrogen receptor mRNA in breast tumours (Pearson's coefficient=0.762, P=0.000). Monoclonal antibodies raised against the TFF3 protein detected TFF3 by immunohistochemistry in oesophageal submucosal glands, intestinal goblet and neuroendocrine cells, Barrett's metaplasia and intestinal metaplasia. TFF3 protein expression was associated with oestrogen receptor, progesterone receptor and TFF1 expression in malignant breast cells. TFF3 is a specific and sensitive predictive biomarker of response to endocrine therapy, degree of response and duration of response in unstratified metastatic breast cancer patients (P=0.000, P=0.002 and P=0.002 respectively). Multivariate binary logistic regression analysis demonstrated that TFF3 is an independent biomarker of endocrine response and degree of response, and this was confirmed in a validation cohort. TFF3 stimulated migration and invasion of breast cancer cells. In conclusion, TFF3 expression is associated with response to endocrine therapy, and outperforms oestrogen receptor, progesterone receptor and TFF1 as an independent biomarker, possibly because it mediates the malign effects of oestrogen on invasion and metastasis.


Assuntos
Neoplasias da Mama/metabolismo , Peptídeos/metabolismo , Animais , Biomarcadores Tumorais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Imuno-Histoquímica , Células MCF-7 , Camundongos , Análise em Microsséries , Metástase Neoplásica , Peptídeos/genética , Coelhos , Fator Trefoil-3 , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
13.
Cancer Manag Res ; 6: 225-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24904222

RESUMO

THE INCIDENCE OF BREAST CANCER CONTINUES TO RISE: 1.7 million women were diagnosed with and 521,000 women died from breast cancer in 2012. This review considers first current treatment options: surgery; radiotherapy; and systemic endocrine, anti-biological, and cytotoxic therapies. Clinical management includes prevention, early detection by screening, treatment with curative intent, management of chronic disease, and palliative control of advanced breast cancer. Next, the potential of novel drugs that target DNA repair, growth factor dependence, intracellular and intercellular signal transduction, and cell cycle are considered. Estrogen-related receptor alpha has attracted attention as a therapeutic target in triple-negative breast cancers with de novo resistance to, and in breast cancers with acquired resistance to, endocrine therapies such as antiestrogens and aromatase inhibitors. Estrogen-related receptor alpha is an orphan receptor and transcription factor. Its activity is regulated by coregulator proteins and posttranslational modification. It is an energy sensor that controls adaptation to energy demand and may facilitate glycolytic metabolism and mitochondrial oxidative respiration in breast cancer cells. Estrogen-related receptor alpha increases breast cancer cell migration, proliferation, and tumor development. It is expressed at high levels in estrogen receptor-negative tumors, and is proposed to activate estrogen-responsive genes in endocrine-resistant tumors. The structures and functions of the ligand-binding domains of estrogen receptor alpha and estrogen-related receptor alpha, their ability to bind estrogens, phytoestrogens, and synthetic ligands, and the effects of ligand agonists, antagonists, and inverse agonists on biological activity, are evaluated. Synthetic ligands of estrogen-related receptor alpha have activity in preclinical models of metabolic disorders, diabetes, osteoporosis, and oncology. The clinical settings in which these novel drugs might have utility in the management of advanced breast cancer, and biomarkers for stratification of patients likely to benefit, are discussed. Finally, the potential side effects of the novel drugs on metabolism, osteoporosis, osteo-metastasis, and cachexia are considered.

14.
Int J Endocrinol ; 2013: 632461, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23983688

RESUMO

Obesity has reached epidemic proportions in the developed world. The progression from obesity to diabetes mellitus type 2, via metabolic syndrome, is recognised, and the significant associated increase in the risk of major human cancers acknowledged. We review the molecular basis of the involvement of morbidly high concentrations of endogenous or therapeutic insulin and of insulin-like growth factors in the progression from obesity to diabetes and finally to cancer. Epidemiological and biochemical studies establish the role of insulin and hyperinsulinaemia in cancer risk and progression. Insulin-like growth factors, IGF-1 and IGF-2, secreted by visceral or mammary adipose tissue have significant paracrine and endocrine effects. These effects can be exacerbated by increased steroid hormone production. Structural studies elucidate how each of the three ligands, insulin, IGF-1, and IGF-2, interacts differently with isoforms A and B of the insulin receptor and with type I IGF receptor and explain how these protagonists contribute to diabetes-associated cancer. The above should inform appropriate treatment of cancers that arise in obese individuals and in those with diabetes mellitus type 2. Novel drugs that target the insulin and insulin-like growth factor signal transduction pathways are in clinical trial and should be effective if appropriate biomarker-informed patient stratification is implemented.

15.
PLoS One ; 7(10): e47300, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23056622

RESUMO

Helicobacter pylori colonises the gastric mucosa of humans. The majority of organisms live in mucus. These organisms are an important reservoir for infection of the underlying epithelium. Cell culture models for H. pylori infection do not normally possess a mucus layer. The interaction of H. pylori with TFF1, a member of the trefoil factor family found in gastric mucin, is mediated by lipopolysaccharide. To test the hypothesis that the interaction of H. pylori with TFF1 promotes mucus colonization we characterised the interaction of H. pylori with a mucus secreting cell line, HT29-MTX-E12. An isogenic mutant of H. pylori with truncated core oligosaccharides was produced and binding to TFF1 and ability to colonise HT29-MTX-E12 cells determined. The adherent mucus layer of HT29-MTX-E12 cells contained the gastric mucin MUC5AC and trefoil factors, TFF1 and TFF3. H. pylori was found within the mucus layer in discrete clusters and in close association with TFF1. It also interacted with the membrane bound mucin MUC1 and replicated when co-cultured with the cells. An isogenic mutant of H. pylori with a truncated LPS core did not interact with TFF1, and colonization of HT29-MTX-E12 cells was reduced compared to the wild-type strain (p<0.05). Preincubation of cells with wild type LPS but not with truncated LPS resulted in reduced colonization by H. pylori. These results demonstrate that the interaction of TFF1 with H. pylori is important for colonization of gastric mucus and the core oligosaccharide of H. pylori LPS is critical for this interaction to occur. HT29-MTX-E12 cells are a useful system with which to study the interaction of bacteria with mucosal surfaces and the effect of such interactions on mediating colonization.


Assuntos
Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiologia , Helicobacter pylori/patogenicidade , Linhagem Celular , Helicobacter pylori/efeitos dos fármacos , Humanos , Lipopolissacarídeos/farmacologia , Mucina-5AC/metabolismo , Peptídeos/metabolismo , Ligação Proteica/efeitos dos fármacos , Fator Trefoil-1 , Fator Trefoil-3 , Proteínas Supressoras de Tumor/metabolismo
17.
Toxicology ; 298(1-3): 40-51, 2012 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-22562034

RESUMO

Primary biliary cirrhosis (PBC) is a cholestatic liver disease of unknown cause that occurs most frequently in post-menopausal women. Since the female sex hormone oestrogen can be cholestatic, we hypothesised that PBC may be triggered in part by chronic exposure to xenoestrogens (which may be more active on a background of low endogenous oestrogen levels seen in post-menopausal women). A reporter gene construct employing a synthetic oestrogen response element predicted to specifically interact with oestrogen receptors (ER) was constructed. Co-transfection of this reporter into an ER null cell line with a variety of nuclear receptor expression constructs indicated that the reporter gene was trans-activated by ERα and ERß, but not by the androgen, thyroid, progesterone, glucocorticoid or vitamin D receptors. Chemicals linked to PBC were then screened for xenoestrogen activity in the human ERα-positive MCF-7 breast cancer cell line. Using this assay, the coal-derived food and cosmetic colourings--sunset yellow and tartrazine--were identified as novel human ERα activators, activating the human ER with an EC(50%) concentration of 220 and 160 nM, respectively.


Assuntos
Compostos Azo/toxicidade , Corantes/toxicidade , Receptor alfa de Estrogênio/metabolismo , Testes Genéticos , Tartrazina/toxicidade , Transcrição Gênica/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Receptor alfa de Estrogênio/agonistas , Feminino , Testes Genéticos/métodos , Humanos , Cirrose Hepática Biliar/induzido quimicamente , Cirrose Hepática Biliar/metabolismo , Transcrição Gênica/fisiologia , Xenobióticos/toxicidade
18.
Am J Pathol ; 180(3): 904-916, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22341453

RESUMO

The trefoil protein TFF3 stimulates invasion and angiogenesis in vitro. To determine whether it has a role in breast tumor metastasis and angiogenesis, its levels were measured by immunohistochemistry in breast tissue with a specific monoclonal antibody raised against human TFF3. TFF3 is expressed in normal breast lobules and ducts, at higher levels in areas of fibrocystic change and papillomas, in all benign breast disease lesions, and in 89% of in situ and in 83% of invasive carcinomas. In well-differentiated tumor cells, TFF3 is concentrated at the luminal edge, whereas in poorly differentiated cells polarity is inverted and expression is directed toward the stroma. Expression was high in well-differentiated tumors and was associated significantly with low histological grade and with estrogen and progesterone receptor expression, accordant with induction of TFF3 mRNA by estrogen in breast cancer cells. Paradoxically, TFF3 expression was associated with muscle, neural, and lymphovascular invasion and the presence and number of involved lymph nodes, and it was an independent predictive marker of lymphovascular invasion and lymph node involvement. Consistent with an angiogenic function, TFF3 expression correlated strongly with microvessel density evaluated with CD31 and CD34. In conclusion, TFF3 is expressed in both the normal and diseased breast. Although associated with features of good prognosis, its profile of expression in invasive cancer is consistent with a role in breast tumor progression and tumor cell dissemination.


Assuntos
Neoplasias da Mama/metabolismo , Mama/metabolismo , Peptídeos/metabolismo , Adolescente , Adulto , Biomarcadores Tumorais/metabolismo , Células Epiteliais/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Invasividade Neoplásica , Metástase Neoplásica , Neovascularização Patológica/metabolismo , Fenótipo , Fator Trefoil-3 , Adulto Jovem
19.
Pharmacogenet Genomics ; 21(12): 808-19, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21946896

RESUMO

OBJECTIVE: A SNP in the NQO1 gene has been implicated in the response of patients with breast cancer to anthracycline containing regimens. NQO1, and its homologue NQO2, share many substrates yet retain distinct functional differences, with NQO2 being a more permissive molecule for electron accepting substrates. We aimed to determine whether functional NQO2 variants are associated with altered response to adjuvant doxorubicin and cyclophosphamide therapy, with or without tamoxifen, in the treatment of breast cancer. METHODS: Genomic DNA samples from 227 women with early breast cancer were genotyped for NQO1 and NQO2 polymorphisms. All participants were treated with an AC adjuvant therapy regimen. The functional implications of NQO2 polymorphisms were validated in in-vitro ectopic expression models. RESULTS: The NQO1 SNP (rs1800566) was associated with a poorer outcome and a lower likelihood of having a treatment delay. Patients who had ER and PR negative disease and were wild type for both the NQO1 and an NQO2 SNP (rs1143684) had 100% 5-year overall survival compared with 88% for carriers of one minor allele and 70% for carriers of two or more minor alleles (P=0.018, log rank). Carriers of minor alleles of a triallelic NQO2 promoter polymorphism were more likely to be withdrawn from tamoxifen therapy prematurely due to intolerance (P=0.009, log rank). MCF-7 cells were sensitized to growth inhibition by doxorubicin and 4OH tamoxifen, but not cyclophosphamide, by ectopic expression of NQO2. CONCLUSION: This study suggests that both NQO1 and NQO2 modulate the efficacy of AC therapy and that NQO2 is associated with tamoxifen toxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , NAD(P)H Desidrogenase (Quinona)/genética , Quinona Redutases/genética , Alelos , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Genótipo , Humanos , Polimorfismo Genético , Tamoxifeno/administração & dosagem
20.
Pancreas ; 40(6): 815-22, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21747314

RESUMO

OBJECTIVES: Trefoil factor 1 (TFF1) is a stable secretory protein expressed widely in the gastrointestinal mucosa that is also expressed in pancreatic ductal adenocarcinoma (PDAC). In the current study, we documented the extent and timing of TFF1 expression and investigated the effects of TFF1 on PDAC cells and stellate cells, the primary cells of the PDAC stroma. METHODS: Trefoil factor 1 expression in pancreatic cancer tissues and cell lines was analyzed using microarray, quantitative reverse transcriptase-polymerase chain reaction, and immunohistochemistry. The effects of recombinant TFF1 on cell growth, migration, and invasion of pancreatic cancer cell lines and immortalized human pancreatic stellate cells (HPSCs) were analyzed using MTS and Matrigel-coated invasion chambers. In vivo studies were also conducted in which Mpanc-96 cells stably expressing TFF1 were implanted orthotopically into nude mice. RESULTS: Trefoil factor 1 was highly increased in preneoplastic lesions. Recombinant TFF1 stimulated motility of both cancer and HPSCs. In contrast, only HPSC cell growth was increased by TFF1. In vivo studies showed that overexpression of TFF1 in PDAC cells did not affect primary tumor growth but greatly increased metastasis. CONCLUSIONS: The present data demonstrate that TFF1 influences both PDAC cells and stellate cells and stimulates metastasis.


Assuntos
Carcinoma Ductal Pancreático/fisiopatologia , Neoplasias Pancreáticas/fisiopatologia , Proteínas Supressoras de Tumor/fisiologia , Animais , Sequência de Bases , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/secundário , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Primers do DNA/genética , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Nus , Invasividade Neoplásica , Transplante de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Células Estreladas do Pâncreas/efeitos dos fármacos , Células Estreladas do Pâncreas/patologia , Células Estreladas do Pâncreas/fisiologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/fisiopatologia , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Heterólogo , Fator Trefoil-1 , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/farmacologia
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