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1.
Clin Cancer Res ; 26(23): 6335-6349, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32943458

RESUMO

PURPOSE: Danvatirsen is a therapeutic antisense oligonucleotide (ASO) that selectively targets STAT3 and has shown clinical activity in two phase I clinical studies. We interrogated the clinical mechanism of action using danvatirsen-treated patient samples and conducted back-translational studies to further elucidate its immunomodulatory mechanism of action. EXPERIMENTAL DESIGN: Paired biopsies and blood samples from danvatirsen-treated patients were evaluated using immunohistochemistry and gene-expression analysis. To gain mechanistic insight, we used mass cytometry, flow cytometry, and immunofluorescence analysis of CT26 tumors treated with a mouse surrogate STAT3 ASO, and human immune cells were treated in vitro with danvatirsen. RESULTS: Within the tumors of treated patients, danvatirsen uptake was observed mainly in cells of the tumor microenvironment (TME). Gene expression analysis comparing baseline and on-treatment tumor samples showed increased expression of proinflammatory genes. In mouse models, STAT3 ASO demonstrated partial tumor growth inhibition and enhanced the antitumor activity when combined with anti-PD-L1. Immune profiling revealed reduced STAT3 protein in immune and stromal cells, and decreased suppressive cytokines correlating with increased proinflammatory macrophages and cytokine production. These changes led to enhanced T-cell abundance and function in combination with anti-PD-L1. CONCLUSIONS: STAT3 ASO treatment reverses a suppressive TME and promotes proinflammatory gene expression changes in patients' tumors and mouse models. Preclinical data provide evidence that ASO-mediated inhibition of STAT3 in the immune compartment is sufficient to remodel the TME and enhance the activity of checkpoint blockade without direct STAT3 inhibition in tumor cells. Collectively, these data provide a rationale for testing this combination in the clinic.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Antígeno B7-H1/antagonistas & inibidores , Neoplasias do Colo/terapia , Neoplasias/terapia , Oligonucleotídeos/farmacologia , Fator de Transcrição STAT3/antagonistas & inibidores , Microambiente Tumoral/imunologia , Ensaios Clínicos Fase I como Assunto , Neoplasias do Colo/imunologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Quimioterapia Combinada , Humanos , Imunomodulação , Macrófagos/imunologia , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Prognóstico , Fator de Transcrição STAT3/genética , Linfócitos T/imunologia , Células Tumorais Cultivadas
2.
Br J Cancer ; 119(11): 1401-1409, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30353044

RESUMO

BACKGROUND: Olaparib (Lynparza™) is a PARP inhibitor approved for advanced BRCA-mutated (BRCAm) ovarian cancer. PARP inhibitors may benefit patients whose tumours are dysfunctional in DNA repair mechanisms unrelated to BRCA1/2. We report exploratory analyses, including the long-term outcome of candidate biomarkers of sensitivity to olaparib in BRCA wild-type (BRCAwt) tumours. METHODS: Tumour samples from an olaparib maintenance monotherapy trial (Study 19, D0810C00019; NCT00753545) were analysed. Analyses included classification of mutations in genes involved in homologous recombination repair (HRR), BRCA1 promoter methylation status, measurement of BRCA1 protein and Myriad HRD score. RESULTS: Patients with BRCAm tumours gained most benefit from olaparib; a similar treatment benefit was also observed in 21/95 patients whose tumours were BRCAwt but had loss-of-function HRR mutations compared to patients with no detectable HRR mutations (58/95). A higher median Myriad MyChoice® HRD score was observed in BRCAm and BRCAwt tumours with BRCA1 methylation. Patients without BRCAm tumours derived benefit from olaparib treatment vs placebo although to a lesser extent than BRCAm patients. CONCLUSIONS: Ovarian cancer patients with tumours harbouring loss-of-function mutations in HRR genes other than BRCA1/2 may constitute a small, molecularly identifiable and clinically relevant population who derive treatment benefit from olaparib similar to patients with BRCAm.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Neoplasias Ovarianas/genética
3.
Cancer Biomark ; 16(1): 145-52, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26577420

RESUMO

BACKGROUND: Poly(ADP)-ribose polymerase (PARP) inhibitors such as olaparib can induce cell death in cancer cells with homologous recombination (HR) DNA repair deficiencies, such as BRCA1/2 mutations. AIM: To identify prognostic biomarkers of long-term outcomes in cancer patients. METHODS: Immunohistochemistry was used to analyse expression of key HR pathway proteins (ATM, ATR, BRCA1, MDC1, MRE11) and PARP-1 in 100 serous ovarian cancer (SOC) and 100 triple-negative breast cancer (TNBC) tumour samples from Japanese patients. RECIST assessment was used. RESULTS: Patient demographic data and BRCA1/2 mutation status were unavailable. Most proteins listed previously were detected in > 80% of tissue samples, with BRCA1 expression detected in 60-65%. A potential link between BRCA1 expression and overall survival (M stage adjusted) in SOC patients was observed, but was not statistically significant after multiple testing adjustment. Correlations between other biomarker expression and survival were not observed. In TNBC patients, MDC1 staining was associated with progressive disease, but this was not statistically significant; the analysis did not identify significant correlations between biomarker expression and disease control. Limited event numbers prevented assessment of the prognostic value of BRCA1 in TNBC. CONCLUSION: BRCA1 expression may be a candidate for a prognostic biomarker in SOC. Further studies are warranted.


Assuntos
Biomarcadores Tumorais , Expressão Gênica , Neoplasias Ovarianas/genética , Reparo de DNA por Recombinação , Neoplasias de Mama Triplo Negativas/genética , Feminino , Humanos , Imuno-Histoquímica , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Prognóstico , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia
4.
BMC Cancer ; 15: 171, 2015 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-25881079

RESUMO

BACKGROUND: To determine the prevalence of RET rearrangement genes, RET copy number gains and expression in tumor samples from four Phase III non-small-cell lung cancer (NSCLC) trials of vandetanib, a selective inhibitor of VEGFR, RET and EGFR signaling, and to determine any association with outcome to vandetanib treatment. METHODS: Archival tumor samples from the ZODIAC ( NCT00312377 , vandetanib ± docetaxel), ZEAL ( NCT00418886 , vandetanib ± pemetrexed), ZEPHYR ( NCT00404924 , vandetanib vs placebo) and ZEST ( NCT00364351 , vandetanib vs erlotinib) studies were evaluated by fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) in 944 and 1102 patients. RESULTS: The prevalence of RET rearrangements by FISH was 0.7% (95% CI 0.3-1.5%) among patients with a known result. Seven tumor samples were positive for RET rearrangements (vandetanib, n = 3; comparator, n = 4). 2.8% (n = 26) of samples had RET amplification (innumerable RET clusters, or ≥7 copies in > 10% of tumor cells), 8.1% (n = 76) had low RET gene copy number gain (4-6 copies in ≥40% of tumor cells) and 8.3% (n = 92) were RET expression positive (signal intensity ++ or +++ in >10% of tumor cells). Of RET-rearrangement-positive patients, none had an objective response in the vandetanib arm and one patient responded in the comparator arm. Radiologic evidence of tumor shrinkage was observed in two patients treated with vandetanib and one treated with comparator drug. The objective response rate was similar in the vandetanib and comparator arms for patients positive for RET copy number gains or RET protein expression. CONCLUSIONS: We have identified prevalence for three RET biomarkers in a population predominated by non-Asians and smokers. RET rearrangement prevalence was lower than previously reported. We found no evidence of a differential benefit for efficacy by IHC and RET gene copy number gains. The low prevalence of RET rearrangements (0.7%) prevents firm conclusions regarding association of vandetanib treatment with efficacy in the RET rearrangement NSCLC subpopulation. TRIAL REGISTRATION: Randomized Phase III clinical trials ( NCT00312377 , ZODIAC; NCT00418886 , ZEAL; NCT00364351 , ZEST; NCT00404924 , ZEPHYR).


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Piperidinas/uso terapêutico , Proteínas Proto-Oncogênicas c-ret/genética , Proteínas Proto-Oncogênicas c-ret/metabolismo , Quinazolinas/uso terapêutico , Idoso , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Feminino , Amplificação de Genes , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Translocação Genética , Resultado do Tratamento
5.
Anticancer Res ; 35(3): 1641-5, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25750322

RESUMO

AIM: Biomarkers with prognostic and predictive value can help stratify patients with colorectal cancer (CRC) into appropriate treatment groups. We sought to evaluate the clinical utility of P53 protein expression as a biomarker in VICTOR, a large phase III trial of rofecoxib in stage II and III CRC. PATIENTS AND METHODS: Tissue micro arrays were constructed from 884 tumors and the expression of P53 was examined by immunohistochemistry. Tumors were dichotomised as either P53-positive (nuclear expression in >10% of cells or the 'absent' pattern, both representing TP53 mutation) or P53-negative (nuclear expression in <10% of cells). RESULTS: Aberrant P53 expression was found in 65% (482/740) of patients. It was associated with distal location (p<0.001) and stage III disease (p<0.001). No effect was observed on disease-free or overall survival, and there was no interaction with chemotherapy or radiotherapy. CONCLUSION: Analysis of P53 expression in the patients recruited to the VICTOR trial confirmed that P53 expression is associated with site and stage of CRC. However, independently, this biomarker has neither prognostic nor predictive utility in this cohort of patients.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Lactonas/uso terapêutico , Sulfonas/uso terapêutico , Proteína Supressora de Tumor p53/análise , Biomarcadores , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Genes p53 , Humanos , Imuno-Histoquímica , Mutação , Estadiamento de Neoplasias , Prognóstico
7.
J Exp Clin Cancer Res ; 33: 47, 2014 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-24886365

RESUMO

INTRODUCTION: Epidermal growth factor receptor (EGFR) overexpression has been associated with prognostic and predictive value in inflammatory breast cancer (IBC). Epidermal growth factor receptor 2 (HER2) overexpression is observed at a higher rate in IBC compared with noninflammatory breast cancer. Current clinically available anti-HER2 therapies are effective only in patients with HER2 amplified breast cancer, including IBC. AZD8931 is a novel small-molecule equipotent inhibitor of EGFR, HER2, and HER3 signaling. In this study, we investigated the antitumor activity of AZD8931 alone or in combination with paclitaxel using preclinical models of EGFR-overexpressed and HER2 non-amplified IBC cells. METHODS: Two IBC cell lines SUM149 and FC-IBC-02 derived from pleural effusion of an IBC patient were used in this study. Cell growth and apoptotic cell death were examined in vitro. For the in vivo tumor growth studies, IBC cells were orthotopically transplanted into the mammary fat pads of immunodeficient mice. AZD8931 was given by daily oral gavage at doses of 25 mg/kg, 5 days/week for 4 weeks. Paclitaxel was subcutaneously injected twice weekly. RESULTS: AZD8931 significantly suppressed cell growth of IBC cells and induced apoptosis of human IBC cells in vitro. Significantly, we showed that AZD8931 monotherapy inhibited xenograft growth and the combination of paclitaxel + AZD8931 was demonstrably more effective than paclitaxel or AZD8931 alone treatment at delaying tumor growth in vivo in orthotopic IBC models. CONCLUSION: AZD8931 single agent and in combination with paclitaxel demonstrated signal inhibition and antitumor activity in EGFR-overexpressed and HER2 non-amplified IBC models. These results suggest that AZD8931 may provide a novel therapeutic strategy for the treatment of IBC patients with HER2 non-amplified tumors.


Assuntos
Antineoplásicos/farmacologia , Receptores ErbB/metabolismo , Neoplasias Inflamatórias Mamárias/tratamento farmacológico , Quinazolinas/farmacologia , Receptor ErbB-2/metabolismo , Receptor ErbB-3/metabolismo , Animais , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Receptores ErbB/antagonistas & inibidores , Feminino , Amplificação de Genes , Humanos , Neoplasias Inflamatórias Mamárias/metabolismo , Camundongos , Camundongos SCID , Quinazolinas/uso terapêutico , Receptor ErbB-2/genética , Transdução de Sinais , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Methods ; 70(1): 34-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24525140

RESUMO

As biomarker discovery takes centre-stage, the role of immunohistochemistry within that process is increasing. At the same time, the number of antibodies being produced for "research use" continues to rise and it is important that antibodies to be used as biomarkers are validated for specificity and sensitivity before use. This guideline seeks to provide a stepwise approach for the validation of an antibody for immunohistochemical assays, reflecting the views of a consortium of academic and pharmaceutical based histopathology researchers. We propose that antibodies are placed into a tier system, level 1-3, based on evidence of their usage in immunohistochemistry, and that the degree of validation required is proportionate to their place on that tier.


Assuntos
Anticorpos/química , Biomarcadores/metabolismo , Imuno-Histoquímica/métodos , Proteínas/química , Animais , Biomarcadores/química , Biomarcadores Tumorais/metabolismo , Pesquisa Biomédica/métodos , Linhagem Celular , Química Farmacêutica/métodos , Epitopos/química , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/imunologia , Neoplasias/metabolismo , Fenótipo , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes
9.
Clin Cancer Res ; 20(3): 595-603, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24284056

RESUMO

PURPOSE: The phosphoinositide 3-kinase (PI3K) pathway is a major oncogenic signaling pathway and an attractive target for therapeutic intervention. Signaling through the PI3K pathway is moderated by the tumor suppressor PTEN, which is deficient or mutated in many human cancers. Molecular characterization of the PI3K signaling network has not been well defined in lung cancer; in particular, the role of PI3Kß and its relation to PTEN in non-small cell lung cancer NSCLC remain unclear. EXPERIMENTAL DESIGN: Antibodies directed against PI3Kß and PTEN were validated and used to examine, by immunohistochemistry, expression in 240 NSCLC resection tissues [tissue microarray (TMA) set 1]. Preliminary observations were extended to an independent set of tissues (TMA set 2) comprising 820 NSCLC patient samples analyzed in a separate laboratory applying the same validated antibodies and staining protocols. The staining intensities for PI3Kß and PTEN were explored and colocalization of these markers in individual tumor cores were correlated. RESULTS: PI3Kß expression was elevated significantly in squamous cell carcinomas (SCC) compared with adenocarcinomas. In contrast, PTEN loss was greater in SCC than in adenocarcinoma. Detailed correlative analyses of individual patient samples revealed a significantly greater proportion of SCC in TMA set 1 with higher PI3Kß and lower PTEN expression when compared with adenocarcinoma. These findings were reinforced following independent analyses of TMA set 2. CONCLUSIONS: We identify for the first time a subset of NSCLC more prevalent in SCC, with elevated expression of PI3Kß accompanied by a reduction/loss of PTEN, for whom selective PI3Kß inhibitors may be predicted to achieve greater clinical benefit.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias Pulmonares/metabolismo , PTEN Fosfo-Hidrolase/biossíntese , Fosfatidilinositol 3-Quinases/biossíntese , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma de Células Escamosas/genética , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Neoplasias Pulmonares/genética , Análise Serial de Tecidos
10.
Clin Cancer Res ; 19(24): 6943-56, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24030704

RESUMO

PURPOSE: The aim of the study was to investigate the vascular and stromal architecture of preclinical tumor models and patient tumor specimens from malignancies with known clinical outcomes to VEGFi treatment, to gain insight into potential determinants of intrinsic sensitivity and resistance. EXPERIMENTAL DESIGN: The tumor stroma architecture of preclinical and clinical tumor samples were analyzed by staining for CD31 and α-smooth muscle actin (α-SMA). Tumor models representative of each phenotype were then tested for sensitivity to the VEGFR2-blocking antibody DC101. RESULTS: Human tumor types with high response rates to VEGF inhibitors (e.g., renal cell carcinoma) have vessels distributed amongst the tumor cells (a "tumor vessel" phenotype, TV). In contrast, those malignancies where single-agent responses are lower, such as non-small cell lung cancer (NSCLC), display a complex morphology involving the encapsulation of tumor cells within stroma that also supports the majority of vessels (a "stromal vessel" phenotype). Only 1 of 31 tumor xenograft models displayed the stromal vessel phenotype. Tumor vessel models were sensitive to VEGFR2-blocking antibody DC101, whereas the stromal vessel models were exclusively refractory. The tumor vessel phenotype was also associated with a better Response Evaluation Criteria in Solid Tumors (RECIST) response to bevacizumab + chemotherapy in metastatic colorectal cancer (CRC). CONCLUSION: The tumor stromal architecture can differentiate between human tumor types that respond to a VEGF signaling inhibitor as single-agent therapy. In addition to reconciling the clinical experience with these agents versus their broad activity in preclinical models, these findings may help to select solid tumor types with intrinsic sensitivity to a VEGFi or other vascular-directed therapies.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Neoplasias/genética , Células Estromais/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Actinas/biossíntese , Anticorpos Monoclonais/administração & dosagem , Bevacizumab , Linhagem Celular Tumoral , Humanos , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/biossíntese , Células Estromais/patologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Mol Cancer Ther ; 12(9): 1715-27, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23861347

RESUMO

Continued androgen receptor (AR) expression and signaling is a key driver in castration-resistant prostate cancer (CRPC) after classical androgen ablation therapies have failed, and therefore remains a target for the treatment of progressive disease. Here, we describe the biological characterization of AZD3514, an orally bioavailable drug that inhibits androgen-dependent and -independent AR signaling. AZD3514 modulates AR signaling through two distinct mechanisms, an inhibition of ligand-driven nuclear translocation of AR and a downregulation of receptor levels, both of which were observed in vitro and in vivo. AZD3514 inhibited testosterone-driven seminal vesicle development in juvenile male rats and the growth of androgen-dependent Dunning R3327H prostate tumors in adult rats. Furthermore, this class of compound showed antitumor activity in the HID28 mouse model of CRPC in vivo. AZD3514 is currently in phase I clinical evaluation.


Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Antineoplásicos/farmacologia , Neoplasias de Próstata Resistentes à Castração/patologia , Piridazinas/farmacologia , Receptores Androgênicos/metabolismo , Glândulas Seminais/efeitos dos fármacos , Acetato de Abiraterona , Antagonistas de Receptores de Andrógenos/metabolismo , Androstadienos/farmacologia , Animais , Antineoplásicos/metabolismo , Benzamidas , Linhagem Celular Tumoral , Modelos Animais de Doenças , Regulação para Baixo , Ensaios de Seleção de Medicamentos Antitumorais , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , Masculino , Camundongos , Camundongos Nus , Nitrilas , Feniltioidantoína/análogos & derivados , Feniltioidantoína/farmacologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Piridazinas/síntese química , Piridazinas/metabolismo , Ratos , Ratos Wistar , Receptores Androgênicos/genética , Glândulas Seminais/crescimento & desenvolvimento , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Histopathology ; 62(6): 827-39, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23672312

RESUMO

Tissue microarrays (TMAs) represent a powerful method for undertaking large-scale tissue-based biomarker studies. While TMAs offer several advantages, there are a number of issues specific to their use which need to be considered when employing this method. Given the investment in TMA-based research, guidance on design and execution of experiments will be of benefit and should help researchers new to TMA-based studies to avoid known pitfalls. Furthermore, a consensus on quality standards for TMA-based experiments should improve the robustness and reproducibility of studies, thereby increasing the likelihood of identifying clinically useful biomarkers. In order to address these issues, the National Cancer Research Institute Biomarker and Imaging Clinical Studies Group organized a 1-day TMA workshop held in Nottingham in May 2012. The document herein summarizes the conclusions from the workshop. It includes guidance and considerations on all aspects of TMA-based research, including the pre-analytical stages of experimental design, the analytical stages of data acquisition, and the postanalytical stages of data analysis. A checklist is presented which can be used both for planning a TMA experiment and interpreting the results of such an experiment. For studies of cancer biomarkers, this checklist could be used as a supplement to the REMARK guidelines.


Assuntos
Análise Serial de Tecidos/normas , Academias e Institutos , Biomarcadores/metabolismo , Interpretação Estatística de Dados , Humanos , Imuno-Histoquímica , Controle de Qualidade , Análise Serial de Tecidos/métodos , Análise Serial de Tecidos/estatística & dados numéricos , Reino Unido
13.
Virchows Arch ; 462(3): 269-79, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23354597

RESUMO

BRCA1 protein measurement has previously been evaluated as a potential diagnostic marker without reaching a conclusive recommendation. In this study, we applied current best practice in antibody validation to further characterize MS110, a widely used antibody targeting BRCA1. Antibody specificity was investigated using different biochemical validation techniques. We found that BRCA1 could not be reliably detected using immunoprecipitation and Western blot in endogenously expressing cells. We used immunohistochemistry on formalin-fixed paraffin-embedded cell pellets to establish compatibility with formalin-fixed paraffin-embedded samples. We demonstrated that in transfected cells and cell lines with known genetic BRCA1 status, MS110 successfully detected BRCA1 giving the expected level of staining in immunohistochemistry. Following this, we investigated the use of BRCA1 protein measurement by immunohistochemistry in a cohort of triple negative breast and serous ovarian tumour samples to explore the use of BRCA1 protein measurement by immunohistochemistry for patient stratification. Using MS110 in repeated standardized experiments, on serial sections from a panel of patient samples, results demonstrated considerable run-to-run variability. We concluded that in formalin-fixed tissue samples, MS110 does detect BRCA1; however, using standard methodologies, BRCA1 expression levels in tissue samples is incompatible with the use of this protein as a statistically robust patient selection marker in immunohistochemistry. These results demonstrate the need for further development to deliver BRCA1 protein quantification by immunohistochemistry as a patient stratification marker.


Assuntos
Anticorpos Monoclonais , Proteína BRCA1/análise , Biomarcadores Tumorais/análise , Neoplasias da Mama/metabolismo , Neoplasias Ovarianas/metabolismo , Proteína BRCA1/genética , Biomarcadores Tumorais/genética , Western Blotting , Neoplasias da Mama/genética , Feminino , Imunofluorescência , Humanos , Imuno-Histoquímica , Imunoprecipitação , Neoplasias Ovarianas/genética , Transcriptoma , Transfecção
15.
Biopharm Drug Dispos ; 32(4): 210-21, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21416475

RESUMO

A clear understanding of oral drug absorption is an important aspect of the drug development process. The permeability of drug compounds across intact sections of small intestine from numerous species, including man, has often been investigated using modified Ussing chambers. The maintenance of viable, intact tissue is critical to the success of this technique. This study therefore aimed to assess the viability and integrity of tissue from patients undergoing pancreatoduodenectomy, for use in cross-species Ussing chamber studies. Electrical parameters (potential difference, mV; short-circuit current, µA.cm(-2) ; resistance, Ω.cm(2) ) were monitored over the duration of each experiment, as was the permeability of the paracellular marker atenolol. The permeability values (Papp; cm/s × 10(-6) ) for a training-set of compounds, displaying a broad range of physicochemical properties and known human fraction absorbed values, were determined in both rat and human jejunum, as well as Caco-2 cell monolayers. The results indicate that human jejunum sourced from pancreatoduodenectomy remained viable and intact for the duration of experiments. Permeability values generated in rat and human jejunum correlate well (R(2) = 0.86), however the relationship between permeability in human tissue and Caco-2 cells was comparatively weak (R(2) = 0.58). Relating permeability to known human fraction absorbed (hFabs) values results in a remarkably similar relationship to both rat and human jejunum Papp values. It can be concluded that human jejunum sourced from pancreatoduodenectomy is a suitable source of tissue for Ussing chamber permeability investigations. The relationship between permeability and hFabs is comparable to results reported using alternative test compounds.


Assuntos
Absorção Intestinal , Intestino Delgado/fisiologia , Jejuno/fisiologia , Pancreaticoduodenectomia , Preparações Farmacêuticas/metabolismo , Antagonistas de Receptores Adrenérgicos beta 1/metabolismo , Adulto , Idoso , Animais , Atenolol/metabolismo , Transporte Biológico , Células CACO-2 , Cultura em Câmaras de Difusão , Humanos , Intestino Delgado/cirurgia , Jejuno/cirurgia , Masculino , Potenciais da Membrana/efeitos dos fármacos , Pessoa de Meia-Idade , Permeabilidade , Ratos , Ratos Wistar , Migração Transendotelial e Transepitelial
16.
Clin Cancer Res ; 16(14): 3548-61, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20606037

RESUMO

PURPOSE: Vascular endothelial growth factor (VEGF) signaling is key to tumor angiogenesis and is an important target in the development of anticancer drugs. However, VEGF receptor (VEGFR) expression in human cancers, particularly the relative expression of VEGFR-2 and VEGFR-3 in tumor vasculature versus tumor cells, is poorly defined. EXPERIMENTAL DESIGN: VEGFR-2- and VEGFR-3-specific antibodies were identified and used in the immunohistochemical analysis of human primary cancers and normal tissue. The relative vascular localization of both receptors in colorectal and breast cancers was determined by coimmunofluorescence with vascular markers. RESULTS: VEGFR-2 and VEGFR-3 were expressed on vascular endothelium but not on malignant cells in 13 common human solid tumor types (n > 400, bladder, breast, colorectal, head and neck, liver, lung, skin, ovarian, pancreatic, prostate, renal, stomach, and thyroid). The signal intensity of both receptors was significantly greater in vessels associated with malignant colorectal, lung, and breast than adjacent nontumor tissue. In colorectal cancers, VEGFR-2 was expressed on both intratumoral blood and lymphatic vessels, whereas VEGFR-3 was found predominantly on lymphatic vessels. In breast cancers, both receptors were localized to and upregulated on blood vessels. CONCLUSIONS: VEGFR-2 and VEGFR-3 are primarily localized to, and significantly upregulated on, tumor vasculature (blood and/or lymphatic) supporting the majority of solid cancers. The primary clinical mechanism of action of VEGF signaling inhibitors is likely to be through the targeting of tumor vessels rather than tumor cells. The upregulation of VEGFR-3 on tumor blood vessels indicates a potential additional antiangiogenic effect for dual VEGFR-2/VEGFR-3-targeted therapy.


Assuntos
Endotélio Vascular/metabolismo , Neoplasias Experimentais/metabolismo , Neoplasias/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/biossíntese , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/biossíntese , Animais , Western Blotting , Linhagem Celular Tumoral , Endotélio Vascular/patologia , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Nus , Camundongos SCID , Células NIH 3T3 , Transplante de Neoplasias , Neoplasias/patologia , Neoplasias Experimentais/patologia
17.
Histopathology ; 57(1): 101-11, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20572881

RESUMO

AIMS: beta-Catenin is an important molecule in cancer biology. Membranous beta-catenin enhances cellular differentiation and inhibits invasion by its action on E-cadherin. The aim was to ascertain whether the cellular expression of these molecules in colorectal and oesophageal cancer specimens is associated with survival in patients with gastrointestinal cancer. METHODS AND RESULTS: Tumour samples from 149 patients undergoing resection for colorectal adenocarcinoma and 147 patients undergoing resection for oesophageal adenocarcinoma were retrospectively analysed using immunohistochemical techniques to assess beta-catenin expression. Increasing beta-catenin expression in the cytoplasm was associated with improved survival for colorectal cancer cases on both univariate (P = 0.003) and multivariate (P = 0.01) analysis. In addition, increased expression in the most recent cohort of oesophageal adenocarcinoma patients was associated with improved TNM staging (P = 0.007). Membrane expression was weakly associated with survival in colorectal cancer on univariate analysis (P = 0.09), but not on multivariate analysis (P = 0.21). Complete absence of beta-catenin expression at all three sites was associated with reduced 5-year survival in colorectal cancer. CONCLUSIONS: This is one of the largest prognostic studies of beta-catenin in gastrointestinal adenocarcinoma. It shows that low levels of cytoplasmic beta-catenin expression are associated with reduced survival in patients with colorectal cancer as well as worse TNM staging in oesophageal adenocarcinoma (a recognized surrogate end-point for survival). We believe this is the first time that this has been reported. This finding should be tested prospectively in oncological trials to validate whether the presence of cytoplasmic beta-catenin could be used as a prognostic marker for less aggressive disease.


Assuntos
Adenocarcinoma/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Gastrointestinais/metabolismo , beta Catenina/metabolismo , Adenocarcinoma/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Citoplasma/metabolismo , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Neoplasias Gastrointestinais/patologia , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Análise Multivariada , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos
18.
Clin Cancer Res ; 15(12): 4138-46, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19509160

RESUMO

PURPOSE: To determine the efficacy of AZD0530, an orally active small molecule Src inhibitor, in human pancreatic cancer xenografts and to seek biomarkers predictive of activity. EXPERIMENTAL DESIGN: Sixteen patient-derived pancreatic cancer xenografts from the PancXenoBank collection at Johns Hopkins were treated with AZD0530 (50 mg/kg/day, p.o.) for 28 days. Baseline gene expression profiles of differently expressed genes in 16 tumors by Affymetrix U133 Plus 2.0 gene array were used to predict AZD0530 sensitivity in an independent group of eight tumors using the K-Top Scoring Pairs (K-TSP) method. RESULTS: Three patient tumors of 16 were found to be sensitive to AZD0530, defined as tumor growth <50% compared with control tumors (100%). Western blot and/or immunohistochemistry results showed that AZD0530 administration resulted in the down-regulation of Src, FAK, p-FAK, p-paxillin, p-STAT-3, and XIAP in sensitive tumor xenografts compared with control tumors. The K-TSP classifier identified one gene pair (LRRC19 and IGFBP2) from the 16 training cases based on a decision rule. The classifier achieved 100% and 83.3% of sensitivity and specificity in an independent test set that consists of eight xenograft cases. CONCLUSIONS: AZD0530 treatment significantly inhibits the tumor growth in a subset of human pancreatic tumor xenografts. One gene pair (LRRC19 and IGFBP2) identified by the K-TSP classifier has high predictive power for AZD0530 sensitivity, suggesting the potential for this gene pair as biomarker for pancreatic tumor sensitivity to AZD0530.


Assuntos
Antineoplásicos/farmacologia , Benzodioxóis/farmacologia , Biomarcadores Tumorais/metabolismo , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/antagonistas & inibidores , Quinazolinas/farmacologia , Animais , Feminino , Quinase 1 de Adesão Focal/antagonistas & inibidores , Quinase 1 de Adesão Focal/metabolismo , Perfilação da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Neoplasias Pancreáticas/patologia , Paxilina/antagonistas & inibidores , Paxilina/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Cell Tissue Bank ; 10(3): 267-70, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18618293

RESUMO

Advances in scientific understanding of disease together with introduction of new high throughput technologies have led to increased demand for human tissue in research. In general, patients are willing to donate for research, particularly samples that are surplus to diagnostic or therapeutic requirements. New tissue-specific regulations in the UK are intended to facilitate the use of human tissue in research. Despite this positive environment there are challenges to researcher access. Coordinated, systematic collection and storage, via a biobank can provide easier access. However translating a vision for a biobank into reality whether in the public or private sector, has never been simple. But it can be done.


Assuntos
Pesquisa Biomédica/tendências , Consentimento Livre e Esclarecido/ética , Bancos de Tecidos/tendências , Humanos
20.
Cell Tissue Bank ; 6(2): 131-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15909101

RESUMO

This report records the Fourth meeting of the European Network of Research Tissue Bank (Brussels, 18th March 2004) which was attended by Mel Read MEP. The existing membership of this informal group represents European Human Research Tissue Bankers, biomedical researchers seeking access to human tissue and allied groups including animal welfare representatives. This Fourth meeting provided a forum to update members on individual activity in this area. A particular focus of this meeting was to consider the status of this group and future affiliations to increase the profile and activity of this Network. This meeting addressed differences in legislative and ethical requirements governing the use of human tissue in biomedical research in the different countries represented. Future activity of the ENRTB, planned at this meeting, will target harmonisation of current differences which are currently barriers to increased access to human tissue for biomedical research. Through the harmonisation of procurement, processing and distribution of human tissue specimens the ENRTB will provide a mechanism to benefit human health through increased use of human tissue in pharmacotoxicological studies and the associated replacement of animal tests.


Assuntos
Pesquisa Biomédica , Bancos de Tecidos , Europa (Continente) , Humanos
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