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1.
Int J Mol Sci ; 22(4)2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33557112

RESUMO

Breast cancer (BCa) is one of the leading health problems among women. Although significant achievements have led to advanced therapeutic success with targeted therapy options, more efforts are required for different subtypes of tumors and according to genomic, transcriptomic, and proteomic alterations. This study underlines the role of microRNA-21 (miR-21) in metastatic MDA-MB-231 breast cancer cells. Following the knockout of miR-21 from MDA-MB-231 cells, which have the highest miR-21 expression levels compared to MCF-7 and SK-BR-3 BCa cells, a decrease in epithelial-mesenchymal transition (EMT) via downregulation of mesenchymal markers was observed. Wnt-11 was a critical target for miR-21, and the Wnt-11 related signaling axis was altered in the stable miR-21 knockout cells. miR-21 expression was associated with a significant increase in mesenchymal markers in MDA-MB-231 BCa cells. Furthermore, the release of extracellular vesicles (EVs) was significantly reduced in the miR-21 KO cells, alongside a significant reduction in relative miR-21 export in EV cargo, compared with control cells. We conclude that miR-21 is a leading factor involved in mesenchymal transition in MDA-MB-231 BCa. Future therapeutic strategies could focus on its role in the treatment of metastatic breast cancer.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33500318

RESUMO

BACKGROUND: It is not known if modifiable lifestyle factors that predict survival after invasive breast cancer differ by subtype. METHODS: We analyzed data for 121,435 women diagnosed with breast cancer from 67 studies in the Breast Cancer Association Consortium with 16,890 deaths (8,554 breast cancer-specific) over 10 years. Cox regression was used to estimate associations between risk factors and 10-year all-cause mortality and breast cancer-specific mortality overall, by estrogen receptor (ER) status, and by intrinsic-like subtype. RESULTS: There was no evidence of heterogeneous associations between risk factors and mortality by subtype (adjusted p>0.30). The strongest associations were between all-cause mortality and BMI {greater than or equal to}30 vs 18.5-25 kg/m2 (HR (95%CI): 1.19 (1.06,1.34)); current vs never smoking (1.37 (1.27,1.47)), high vs low physical activity (0.43 (0.21,0.86)), age {greater than or equal to}30 years vs <20 years at first pregnancy (0.79 (0.72,0.86)); >0 to <5 years vs {greater than or equal to}10 years since last full term birth (1.31 (1.11,1.55)); ever vs never use of oral contraceptives (0.91 (0.87,0.96)); ever vs never use of menopausal hormone therapy, including current estrogen-progestin therapy (0.61 (0.54,0.69)). Similar associations with breast cancer mortality were weaker; e.g. 1.11 (1.02,1.21) for current vs never smoking. CONCLUSIONS: We confirm associations between modifiable lifestyle factors and 10-year all-cause mortality. There was no strong evidence that associations differed by ER status or intrinsic-like subtype. IMPACT: Given the large dataset and lack of evidence that associations between modifiable risk factors and 10-year mortality differed by subtype, these associations could be cautiously used in prognostication models to inform patient-centered care.

3.
Am J Hum Genet ; 107(5): 837-848, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33022221

RESUMO

Previous research has shown that polygenic risk scores (PRSs) can be used to stratify women according to their risk of developing primary invasive breast cancer. This study aimed to evaluate the association between a recently validated PRS of 313 germline variants (PRS313) and contralateral breast cancer (CBC) risk. We included 56,068 women of European ancestry diagnosed with first invasive breast cancer from 1990 onward with follow-up from the Breast Cancer Association Consortium. Metachronous CBC risk (N = 1,027) according to the distribution of PRS313 was quantified using Cox regression analyses. We assessed PRS313 interaction with age at first diagnosis, family history, morphology, ER status, PR status, and HER2 status, and (neo)adjuvant therapy. In studies of Asian women, with limited follow-up, CBC risk associated with PRS313 was assessed using logistic regression for 340 women with CBC compared with 12,133 women with unilateral breast cancer. Higher PRS313 was associated with increased CBC risk: hazard ratio per standard deviation (SD) = 1.25 (95%CI = 1.18-1.33) for Europeans, and an OR per SD = 1.15 (95%CI = 1.02-1.29) for Asians. The absolute lifetime risks of CBC, accounting for death as competing risk, were 12.4% for European women at the 10th percentile and 20.5% at the 90th percentile of PRS313. We found no evidence of confounding by or interaction with individual characteristics, characteristics of the primary tumor, or treatment. The C-index for the PRS313 alone was 0.563 (95%CI = 0.547-0.586). In conclusion, PRS313 is an independent factor associated with CBC risk and can be incorporated into CBC risk prediction models to help improve stratification and optimize surveillance and treatment strategies.

4.
Sci Rep ; 10(1): 12020, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32694700

RESUMO

3D laboratory models of cancer are designed to recapitulate the biochemical and biophysical characteristics of the tumour microenvironment and aim to enable studies of cancer, and new therapeutic modalities, in a physiologically-relevant manner. We have developed an in vitro 3D model comprising a central high-density mass of breast cancer cells surrounded by collagen type-1 and we incorporated fluid flow and pressure. We noted significant changes in cancer cell behaviour using this system. MDA-MB231 and SKBR3 breast cancer cells grown in 3D downregulated the proliferative marker Ki67 (P < 0.05) and exhibited decreased response to the chemotherapeutic agent doxorubicin (DOX) (P < 0.01). Mesenchymal markers snail and MMP14 were upregulated in cancer cells maintained in 3D (P < 0.001), cadherin-11 was downregulated (P < 0.001) and HER2 increased (P < 0.05). Cells maintained in 3D under fluid flow exhibited a further reduction in response to DOX (P < 0.05); HER2 and Ki67 levels were also attenuated. Fluid flow and pressure was associated with reduced cell viability and decreased expression levels of vimentin. In summary, aggressive cancer cell behaviour and reduced drug responsiveness was observed when breast cancer cells were maintained in 3D under fluid flow and pressure. These observations are relevant for future developments of 3D in vitro cancer models and organ-on-a-chip initiatives.

5.
Sci Rep ; 10(1): 9688, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546843

RESUMO

In breast cancer, high levels of homeobox protein Hox-B13 (HOXB13) have been associated with disease progression of ER-positive breast cancer patients and resistance to tamoxifen treatment. Since HOXB13 p.G84E is a prostate cancer risk allele, we evaluated the association between HOXB13 germline mutations and breast cancer risk in a previous study consisting of 3,270 familial non-BRCA1/2 breast cancer cases and 2,327 controls from the Netherlands. Although both recurrent HOXB13 mutations p.G84E and p.R217C were not associated with breast cancer risk, the risk estimation for p.R217C was not very precise. To provide more conclusive evidence regarding the role of HOXB13 in breast cancer susceptibility, we here evaluated the association between HOXB13 mutations and increased breast cancer risk within 81 studies of the international Breast Cancer Association Consortium containing 68,521 invasive breast cancer patients and 54,865 controls. Both HOXB13 p.G84E and p.R217C did not associate with the development of breast cancer in European women, neither in the overall analysis (OR = 1.035, 95% CI = 0.859-1.246, P = 0.718 and OR = 0.798, 95% CI = 0.482-1.322, P = 0.381 respectively), nor in specific high-risk subgroups or breast cancer subtypes. Thus, although involved in breast cancer progression, HOXB13 is not a material breast cancer susceptibility gene.

6.
Nat Commun ; 11(1): 312, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949161

RESUMO

Identifying the underlying genetic drivers of the heritability of breast cancer prognosis remains elusive. We adapt a network-based approach to handle underpowered complex datasets to provide new insights into the potential function of germline variants in breast cancer prognosis. This network-based analysis studies ~7.3 million variants in 84,457 breast cancer patients in relation to breast cancer survival and confirms the results on 12,381 independent patients. Aggregating the prognostic effects of genetic variants across multiple genes, we identify four gene modules associated with survival in estrogen receptor (ER)-negative and one in ER-positive disease. The modules show biological enrichment for cancer-related processes such as G-alpha signaling, circadian clock, angiogenesis, and Rho-GTPases in apoptosis.


Assuntos
Neoplasias da Mama/genética , Variação Genética , Estudo de Associação Genômica Ampla , Células Germinativas , Apoptose , Relógios Circadianos , Biologia Computacional , Feminino , Subunidades alfa de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/genética , Redes Reguladoras de Genes , Genótipo , Humanos , Prognóstico , Receptores Estrogênicos/genética , Transdução de Sinais
7.
Sci Rep ; 9(1): 12524, 2019 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-31467304

RESUMO

Fanconi anemia (FA) is a genetically heterogeneous disorder with 22 disease-causing genes reported to date. In some FA genes, monoallelic mutations have been found to be associated with breast cancer risk, while the risk associations of others remain unknown. The gene for FA type C, FANCC, has been proposed as a breast cancer susceptibility gene based on epidemiological and sequencing studies. We used the Oncoarray project to genotype two truncating FANCC variants (p.R185X and p.R548X) in 64,760 breast cancer cases and 49,793 controls of European descent. FANCC mutations were observed in 25 cases (14 with p.R185X, 11 with p.R548X) and 26 controls (18 with p.R185X, 8 with p.R548X). There was no evidence of an association with the risk of breast cancer, neither overall (odds ratio 0.77, 95%CI 0.44-1.33, p = 0.4) nor by histology, hormone receptor status, age or family history. We conclude that the breast cancer risk association of these two FANCC variants, if any, is much smaller than for BRCA1, BRCA2 or PALB2 mutations. If this applies to all truncating variants in FANCC it would suggest there are differences between FA genes in their roles on breast cancer risk and demonstrates the merit of large consortia for clarifying risk associations of rare variants.


Assuntos
Neoplasias da Mama/genética , Proteína do Grupo de Complementação C da Anemia de Fanconi/genética , Deleção de Sequência , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/metabolismo , Estudos de Casos e Controles , Anemia de Fanconi/genética , Proteína do Grupo de Complementação C da Anemia de Fanconi/metabolismo , Feminino , Predisposição Genética para Doença , Variação Genética , Humanos
8.
Interface Focus ; 9(2): 20180079, 2019 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-30842877

RESUMO

The lectin Helix pomatia agglutinin (HPA) recognizes altered glycosylation in solid cancers and the identification of HPA binding partners in tumour tissue and serum is an important aim. Among the many HPA binding proteins, IgA1 has been reported to be the most abundant in liver metastases. In this study, the glycosylation of IgA1 was evaluated using serum samples from patients with breast cancer (BCa) and the utility of IgA1 glycosylation as a biomarker was assessed. Detailed mass spectrometric structural analysis showed an increase in disialo-biantennary N-linked glycans on IgA1 from BCa patients (p < 0.0001: non-core fucosylated; p = 0.0345: core fucosylated) and increased asialo-Thomsen-Friedenreich antigen (TF) and disialo-TF antigens in the O-linked glycan preparations from IgA1 of cancer patients compared with healthy control individuals. An increase in Sambucus nigra binding was observed, suggestive of increased α2,6-linked sialic acid on IgA1 in BCa. Logistic regression analysis showed HPA binding to IgA1 and tumour size to be significant independent predictors of distant metastases (χ 2 13.359; n = 114; p = 0.020) with positive and negative predictive values of 65.7% and 64.6%, respectively. Immunohistochemical analysis of tumour tissue samples showed IgA1 to be detectable in BCa tissue. This report provides a detailed analysis of serum IgA1 glycosylation in BCa and illustrates the potential utility of IgA1 glycosylation as a biomarker for BCa prognostication.

9.
Sci Rep ; 7: 43006, 2017 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-28223691

RESUMO

Alterations in protein glycosylation are a key feature of oncogenesis and have been shown to affect cancer cell behaviour perturbing cell adhesion, favouring cell migration and metastasis. This study investigated the effect of N-linked glycosylation on the binding of Herceptin to HER2 protein in breast cancer and on the sensitivity of cancer cells to the chemotherapeutic agent doxorubicin (DXR) and growth factors (EGF and IGF-1). The interaction between Herceptin and recombinant HER2 protein and cancer cell surfaces (on-rate/off-rate) was assessed using a quartz crystal microbalance biosensor revealing an increase in the accessibility of HER2 to Herceptin following deglycosylation of cell membrane proteins (deglycosylated cells Bmax: 6.83 Hz; glycosylated cells Bmax: 7.35 Hz). The sensitivity of cells to DXR and to growth factors was evaluated using an MTT assay. Maintenance of SKBR-3 cells in tunicamycin (an inhibitor of N-linked glycosylation) resulted in an increase in sensitivity to DXR (0.1 µM DXR P < 0.001) and a decrease in sensitivity to IGF-1 alone and to IGF-1 supplemented with EGF (P < 0.001). This report illustrates the importance of N-linked glycosylation in modulating the response of cancer cells to chemotherapeutic and biological treatments and highlights the potential of glycosylation inhibitors as future combination treatments for breast cancer.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/farmacologia , Fator de Crescimento Epidérmico/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Trastuzumab/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Concanavalina A/metabolismo , Sinergismo Farmacológico , Feminino , Glicosilação/efeitos dos fármacos , Humanos , Cinética , Microscopia de Fluorescência , Ligação Proteica , Técnicas de Microbalança de Cristal de Quartzo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Tunicamicina/farmacologia
10.
Br J Cancer ; 114(9): 1019-26, 2016 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-27010749

RESUMO

BACKGROUND: A glycoproteomic study has previously shown cadherin-5 (CDH5) to be a serological marker of metastatic breast cancer when both protein levels and glycosylation status were assessed. In this study we aimed to further validate the utility of CDH5 as a biomarker for breast cancer progression. METHODS: A nested case-control study of serum samples from breast cancer patients, of which n=52 had developed a distant metastatic recurrence within 5 years post-diagnosis and n=60 had remained recurrence-free. ELISAs were used to quantify patient serum CDH5 levels and assess glycosylation by Helix pomatia agglutinin (HPA) binding. Clinicopathological, treatment and lifestyle factors associated with metastasis and elevated biomarker levels were identified. RESULTS: Elevated CDH5 levels (P=0.028) and ratios of CDH5:HPA binding (P=0.007) distinguished patients with metastatic disease from those that remained metastasis-free. Multivariate analysis showed that the association between CDH5:HPA ratio and the formation of distant metastases was driven by patients with oestrogen receptor (ER+) positive cancer with vascular invasion (VI+). CONCLUSIONS: CDH5 levels and the CDH5 glycosylation represent biomarker tests that distinguish patients with metastatic breast cancer from those that remain metastasis-free. The test reached optimal sensitivity and specificity in ER-positive cancers with vascular invasion.


Assuntos
Antígenos CD/metabolismo , Neoplasias da Mama/genética , Caderinas/metabolismo , Adulto , Idoso , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Receptores Estrogênicos/metabolismo
11.
Nanomedicine (Lond) ; 11(4): 331-44, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26786002

RESUMO

AIM: In this work, we use cationic organic nanocarriers as chemotherapy delivery platforms and test them in a colorectal cancer 3D in vitro model. MATERIALS & METHODS: We used 3beta-(N-[N',N'-dimethylaminoethane]carbamoyl])cholesterol (DC-chol) and dioleoylphosphatidylethanolamine (DOPE) liposomes and N-palmitoyl-N-monomethyl-N,N-dimethyl-N,N,N-trimethyl-6-O-glycolchitosan (GCPQ) micelles, to deliver AZD6244, a MEK inhibitor, to HCT116 cells cultured as monolayers and in 3D in vitro cancer models (tumoroids). RESULTS: Nanoparticle-mediated drug delivery was superior to the free drug in monolayer experiments and despite their therapeutic effect being hindered by poor diffusion through the cancer mass, GCPQ micelles were also superior in tumoroids. CONCLUSION: These results support the role of nanoparticles in improving drug delivery and highlight the need to include 3D cancer models in early phases of drug development.


Assuntos
Antineoplásicos/administração & dosagem , Benzimidazóis/administração & dosagem , Colesterol/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Portadores de Fármacos , Lipossomos , Micelas , Neoplasias Colorretais/patologia , Humanos , Técnicas In Vitro
12.
PLoS One ; 10(10): e0138345, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26495974

RESUMO

BACKGROUND: Protein glycosylation is an important post-translational modification shown to be altered in all tumour types studied to date. Mucin glycoproteins have been established as important carriers of O-linked glycans but other glycoproteins exhibiting altered glycosylation repertoires have yet to be identified but offer potential as biomarkers for metastatic cancer. METHODOLOGY: In this study a glycoproteomic approach was used to identify glycoproteins exhibiting alterations in glycosylation in colorectal cancer and to evaluate the changes in O-linked glycosylation in the context of the p53 and KRAS (codon 12/13) mutation status. Affinity purification with the carbohydrate binding protein from Helix pomatia agglutinin (HPA) was coupled to 2-dimensional gel electrophoresis with mass spectrometry to enable the identification of low abundance O-linked glycoproteins from human colorectal cancer specimens. RESULTS: Aberrant O-linked glycosylation was observed to be an early event that occurred irrespective of the p53 and KRAS status and correlating with metastatic colorectal cancer. Affinity purification using the lectin HPA followed by proteomic analysis revealed annexin 4, annexin 5 and CLCA1 to be increased in the metastatic colorectal cancer specimens. The results were validated using a further independent set of specimens and this showed a significant association between the staining score for annexin 4 and HPA and the time to metastasis; independently (annexin A4: Chi square 11.45, P = 0.0007; HPA: Chi square 9.065, P = 0.0026) and in combination (annexin 4 and HPA combined: Chi square 13.47; P = 0.0002). CONCLUSION: Glycoproteins showing changes in O-linked glycosylation in metastatic colorectal cancer have been identified. The glycosylation changes were independent of p53 and KRAS status. These proteins offer potential for further exploration as biomarkers and potential targets for metastatic colorectal cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Glicoproteínas/metabolismo , Lectinas/metabolismo , Análise Mutacional de DNA , Eletroforese em Gel Bidimensional , Glicosilação , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Metástase Neoplásica , Ligação Proteica , Proteômica , Proteínas Proto-Oncogênicas p21(ras)/genética , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Proteína Supressora de Tumor p53/metabolismo
13.
PLoS Genet ; 10(4): e1004285, 2014 04.
Artigo em Inglês | MEDLINE | ID: mdl-24743323

RESUMO

Invasive lobular breast cancer (ILC) accounts for 10-15% of all invasive breast carcinomas. It is generally ER positive (ER+) and often associated with lobular carcinoma in situ (LCIS). Genome-wide association studies have identified more than 70 common polymorphisms that predispose to breast cancer, but these studies included predominantly ductal (IDC) carcinomas. To identify novel common polymorphisms that predispose to ILC and LCIS, we pooled data from 6,023 cases (5,622 ILC, 401 pure LCIS) and 34,271 controls from 36 studies genotyped using the iCOGS chip. Six novel SNPs most strongly associated with ILC/LCIS in the pooled analysis were genotyped in a further 516 lobular cases (482 ILC, 36 LCIS) and 1,467 controls. These analyses identified a lobular-specific SNP at 7q34 (rs11977670, OR (95%CI) for ILC = 1.13 (1.09-1.18), P = 6.0 × 10(-10); P-het for ILC vs IDC ER+ tumors = 1.8 × 10(-4)). Of the 75 known breast cancer polymorphisms that were genotyped, 56 were associated with ILC and 15 with LCIS at P<0.05. Two SNPs showed significantly stronger associations for ILC than LCIS (rs2981579/10q26/FGFR2, P-het = 0.04 and rs889312/5q11/MAP3K1, P-het = 0.03); and two showed stronger associations for LCIS than ILC (rs6678914/1q32/LGR6, P-het = 0.001 and rs1752911/6q14, P-het = 0.04). In addition, seven of the 75 known loci showed significant differences between ER+ tumors with IDC and ILC histology, three of these showing stronger associations for ILC (rs11249433/1p11, rs2981579/10q26/FGFR2 and rs10995190/10q21/ZNF365) and four associated only with IDC (5p12/rs10941679; rs2588809/14q24/RAD51L1, rs6472903/8q21 and rs1550623/2q31/CDCA7). In conclusion, we have identified one novel lobular breast cancer specific predisposition polymorphism at 7q34, and shown for the first time that common breast cancer polymorphisms predispose to LCIS. We have shown that many of the ER+ breast cancer predisposition loci also predispose to ILC, although there is some heterogeneity between ER+ lobular and ER+ IDC tumors. These data provide evidence for overlapping, but distinct etiological pathways within ER+ breast cancer between morphological subtypes.


Assuntos
Neoplasias da Mama/genética , Carcinoma in Situ/genética , Carcinoma Lobular/genética , Predisposição Genética para Doença/genética , Estudos de Casos e Controles , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética
14.
Appl Biochem Biotechnol ; 171(4): 963-74, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23912210

RESUMO

The terminal monosaccharide of glycoconjugates on a eukaryotic cell surface is typically a sialic acid (Neu5Ac). Increased sialylation usually indicates progression and poor prognosis of most carcinomas. Here, we utilize two human mammary epithelial cell lines, HB4A (breast normal cells) and T47D (breast cancer cells), as a model system to demonstrate differential surface glycans when treated with sialic acid under nutrient deprivation. Under a starved condition, sialic acid treatment of both cells resulted in increased activities of α2→3/6 sialyltransferases as demonstrated by solid phase assay using lectin binding. However, a very strong Maackia amurensis agglutinin I (MAL-I) staining on the membrane of sialic acid-treated T47D cells was observed, indicating an increase of Neu5Acα2→3Gal on the cell surface. To our knowledge, this is a first report showing the utility of lectins, particularly MAL-I, as a means to discriminate between normal and cancer cells after sialic acid treatment under nutrient deprivation. This method is sensitive and allows selective detection of glycan sialylation on a cancer cell surface.


Assuntos
Lectinas/metabolismo , Ácido N-Acetilneuramínico/farmacologia , Polissacarídeos/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citometria de Fluxo , Humanos , Microscopia Confocal
15.
Maturitas ; 75(3): 232-40, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23664318

RESUMO

DietCompLyf is a multi-centre prospective study designed to investigate associations between phytoestrogens - naturally occurring plant compounds with oestrogenic properties - and other diet and lifestyle factors with breast cancer recurrence and survival. 3159 women with grades I-III breast cancer were recruited 9-15 months post-diagnosis from 56 UK hospitals. Detailed information on clinico-pathological, diet, lifestyle and quality of life is collected annually up to 5 years. Biological samples have also been collected as a resource for subsequent evaluation. The characteristics of the patients and associations between pre-diagnosis intake of phytoestrogens (isoflavones and lignans; assessed using the EPIC-Norfolk UK 130 question food frequency questionnaire) and breast cancer (i) risk factors and (ii) prognostic factors are described for 1797 women who had complete data for all covariates and phytoestrogens of interest. Isoflavone intakes were higher in the patients who were younger at diagnosis, in the non-smokers, those who had breast-fed and those who took supplements. Lignan intakes were higher in patients with a higher age at diagnosis, in ex-smokers, those who had breast-fed, who took supplements, had a lower BMI at diagnosis, lower age at menarche and were nulliparous. No significant associations between pre-diagnosis phytoestrogen intake and factors associated with improved breast cancer prognosis were observed. The potential for further exploration of the relationship between phytoestrogens and breast cancer recurrence and survival, and for the establishment of evidence to improve dietary and lifestyle advice offered to patients following breast cancer diagnosis using DietCompLyf data is discussed.


Assuntos
Neoplasias da Mama , Isoflavonas/farmacologia , Lignanas/farmacologia , Fitoestrógenos/farmacologia , Extratos Vegetais/farmacologia , Sobreviventes , Adulto , Fatores Etários , Aleitamento Materno , Neoplasias da Mama/diagnóstico , Inquéritos sobre Dietas , Suplementos Nutricionais , Feminino , Humanos , Menarca , Pessoa de Meia-Idade , Paridade , Prognóstico , Estudos Prospectivos , Recidiva , Fumar , Inquéritos e Questionários , Reino Unido
16.
Int J Nanomedicine ; 8: 941-50, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23487255

RESUMO

Cancer is one of the leading causes of death worldwide and early detection provides the best possible prognosis for cancer patients. Nanotechnology is the branch of engineering that deals with the manipulation of individual atoms and molecules. This area of science has the potential to help identify cancerous cells and to destroy them by various methods such as drug delivery or thermal treatment of cancer. Carbon nanotubes (CNT) and quantum dots (QDs) are the two nanoparticles, which have received considerable interest in view of their application for diagnosis and treatment of cancer. Fluorescent nanoparticles known as QDs are gaining momentum as imaging molecules with life science and clinical applications. Clinically they can be used for localization of cancer cells due to their nano size and ability to penetrate individual cancer cells and high-resolution imaging derived from their narrow emission bands compared with organic dyes. CNTs are of interest to the medical community due to their unique properties such as the ability to deliver drugs to a site of action or convert optical energy into thermal energy. By attaching antibodies that bind specifically to tumor cells, CNTs can navigate to malignant tumors. Once at the tumor site, the CNTs enter into the cancer cells by penetration or endocytosis, allowing drug release, and resulting in specific cancer cell death. Alternatively, CNTs can be exposed to near-infrared light in order to thermally destroy the cancer cells. The amphiphilic nature of CNTs allows them to penetrate the cell membrane and their large surface area (in the order of 2600 m(2)/g) allows drugs to be loaded into the tube and released once inside the cancer cell. Many research laboratories, including our own, are investigating the conjugation of QDs to CNTs to allow localization of the cancer cells in the patient, by imaging with QDs, and subsequent cell killing, via drug release or thermal treatment. This is an area of huge interest and future research and therapy will focus on the multimodality of nanoparticles. In this review, we seek to explore the biomedical applications of QDs conjugated to CNTs, with a particular emphasis on their use as therapeutic platforms in oncology.


Assuntos
Diagnóstico por Imagem/métodos , Sistemas de Liberação de Medicamentos/métodos , Nanomedicina/métodos , Nanotubos de Carbono/química , Pontos Quânticos , Humanos , Fototerapia
17.
Cancer Lett ; 328(2): 335-44, 2013 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-23079531

RESUMO

Aberrant glycosylation has long been recognised as a hallmark of cancer, and is increasingly being exploited in biomarker discovery studies. Helix pomatia agglutinin (HPA) is known to bind aberrant glycans associated with metastatic breast cancer, and was used here to isolate glycoproteins from pooled breast cancer serum samples of (i) patients with recurrent breast cancer and (ii) patients with no sign of recurrence 5years after diagnosis of their primary tumour. Pregnancy zone protein, the polymeric immunoglobulin receptor and cadherin-5 emerged as potential markers of metastasis following proteomic identification of HPA binding glycoproteins. ELISAs were developed to verify these findings, and to assess protein glycosylation, in individual patient sera. The cadherin-5 ELISA discriminated serum samples of patients with recurrent breast cancer from those with no sign of recurrence, and analysis of cadherin-5 glycosylation by HPA also showed a significant difference between the two sample groups. The targeted glycoproteomic and validatory approach developed here has shown that when taking into account both the protein levels and HPA binding, serum cadherin-5 discriminated patients with recurrent breast cancer from those with no sign of recurrence with 90% specificity.


Assuntos
Antígenos CD/sangue , Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Caderinas/sangue , Glicoproteínas/sangue , Proteoma , Proteômica , Adulto , Idoso , Antígenos CD/metabolismo , Caderinas/metabolismo , Feminino , Glicoproteínas/metabolismo , Humanos , Lectinas/metabolismo , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Ligação Proteica , Proteômica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Methods Mol Biol ; 878: 111-20, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22674129

RESUMO

Two-dimensional electrophoresis (2-DE) is a high-resolution technique for analysis and comparison of complex protein mixtures. With the advent of recent technical developments, its application has become significant in a wide range of fields. This chapter describes a proteomic approach for the analysis of metastasis-associated proteins using pre-fractionation of glycosylated proteins via lectin (HPA) affinity chromatography prior to separation by 2-DE. Guidelines for the preparation and storage of buffers, experimental conditions and protocols of affinity chromatography, isoelectric focussing, and SDS-PAGE conditions are provided. Critical parameters associated with the different steps of 2-DE are discussed.


Assuntos
Eletroforese em Gel Bidimensional/métodos , Glicoproteínas/análise , Glicoproteínas/isolamento & purificação , Proteômica/métodos , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Humanos , Concentração de Íons de Hidrogênio , Focalização Isoelétrica , Lectinas/metabolismo , Metástase Neoplásica
19.
Methods Mol Biol ; 878: 267-72, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22674140

RESUMO

Since 2005, lectin microarray technology has emerged as a relatively simple yet powerful technique for the comprehensive analysis of glycoprotein glycosylation. Lectin microarrays represent a new analytical method that can be used to explore the human glycome, a unique source of markers of diseases including cancer. The lectin microarray technology is a sensitive tool with the potential to allow high-throughput analysis of cancer-associated changes in glycosylation. This chapter describes the generation of a lectin-binding signature associated with metastatic primary breast tumours that have been resected, fixed, and embedded in paraffin. Procedures concerning sample and lectin microarray preparation are explained, alongside experimental considerations and approaches to data analysis.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Lectinas/metabolismo , Análise Serial de Proteínas/métodos , Formaldeído/metabolismo , Glicosilação , Humanos , Metástase Neoplásica , Inclusão em Parafina , Fixação de Tecidos
20.
Curr Opin Pharmacol ; 12(4): 408-13, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22560919

RESUMO

Nearly all proteins are modified in post translational events, indeed, understanding the control and function of post translational modifications (PTMs) is arguably the 'next frontier' for cancer cell biologists. The most well understood PTMs include glycosylation, phosphorylation, ubiquitination, methylation and palmitylation. Each of these modifications has been observed to be altered in cancer, affecting key cellular pathways including signal transduction, cell membrane receptor function, and protein-protein interactions. A number of strategies have been proposed that aim to target the modified proteins themselves, the enzymes that construct them, or that boost host-cellular immunity against modified residues aberrantly expressed in cancer.


Assuntos
Neoplasias/metabolismo , Processamento de Proteína Pós-Traducional , Genoma , Glicosilação , Humanos , Fosforilação , Proteoma
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