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1.
ACS Cent Sci ; 9(3): 476-487, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36968530

RESUMEN

In recent years there has been rising interest in the field of protein-protein conjugation, especially related to bispecific antibodies (bsAbs) and their therapeutic applications. These constructs contain two paratopes capable of binding two distinct epitopes on target molecules and are thus able to perform complex biological functions (mechanisms of action) not available to monospecific mAbs. Traditionally these bsAbs have been constructed through protein engineering, but recently chemical methods for their construction have started to (re)emerge. While these have been shown to offer increased modularity, speed, and for some methods even the inherent capacity for further functionalization (e.g., with small molecule cargo), most of these approaches lacked the ability to include a fragment crystallizable (Fc) modality. The Fc component of IgG antibodies offers effector function and increased half-life. Here we report a first-in-class disulfide rebridging and click-chemistry-based method for the generation of Fc-containing, IgG-like mono- and bispecific antibodies. These are in the FcZ-(FabX)-FabY format, i.e., two distinct Fabs and an Fc, potentially all from different antibodies, attached in a homogeneous and covalent manner. We have dubbed these molecules synthetic antibodies (SynAbs). We have constructed a T cell-engager (TCE) SynAb, FcCD20-(FabHER2)-FabCD3, and have confirmed that it exhibits the expected biological functions, including the ability to kill HER2+ target cells in a coculture assay with T cells.

2.
Int J Mol Sci ; 24(6)2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36982791

RESUMEN

Paediatric acute myeloid leukaemia (AML) continues to present treatment challenges, as no "standard approach" exists to treat those young patients reliably and safely. Combination therapies could become a viable treatment option for treating young patients with AML, allowing multiple pathways to be targeted. Our in silico analysis of AML patients highlighted "cell death and survival" as an aberrant, potentially targetable pathway in paediatric AML patients. Therefore, we aimed to identify novel combination therapies to target apoptosis. Our apoptotic drug screening resulted in the identification of one potential "novel" drug pairing, comprising the Bcl-2 inhibitor ABT-737 combined with the CDK inhibitor Purvalanol-A, as well as one triple combination of ABT-737 + AKT inhibitor + SU9516, which showed significant synergism in a series of paediatric AML cell lines. Using a phosphoproteomic approach to understand the apoptotic mechanism involved, proteins related to apoptotic cell death and cell survival were represented, in agreement with further results showing differentially expressed apoptotic proteins and their phosphorylated forms among combination treatments compared to single-agent treated cells such upregulation of BAX and its phosphorylated form (Thr167), dephosphorylation of BAD (Ser 112), and downregulation of MCL-1 and its phosphorylated form (Ser159/Thr 163). Total levels of Bcl-2 were decreased but correlated with increased levels of phosphorylated Bcl-2, which was consistent with our phosphoproteomic analysis predictions. Bcl-2 phosphorylation was regulated by extracellular-signal-regulated kinase (ERK) but not PP2A phosphatase. Although the mechanism linking to Bcl-2 phosphorylation remains to be determined, our findings provide first-hand insights on potential novel combination treatments for AML.


Asunto(s)
Leucemia Mieloide Aguda , Niño , Humanos , Línea Celular Tumoral , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Apoptosis
3.
Cancers (Basel) ; 14(15)2022 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-35954391

RESUMEN

Drug resistance limits the effectiveness of oesophageal adenocarcinoma (OAC) chemotherapies, leading to a poor prognosis for this disease. Elucidation of the underlying resistance mechanisms is key to enabling the identification of more effective treatments. This study, therefore, aims to identify novel therapeutic and/or chemotherapy sensitising drug targets in OAC. Transcriptional data from a cohort of 273 pre-treatment OAC biopsies, from patients who received neoadjuvant chemotherapy followed by surgical resection, were analysed using gene set enrichment analysis (GSEA) to determine differential gene expression between responding and non-responding OAC tumours. From this, 80 genes were selected for high-throughput siRNA screening in OAC cell lines with or without standard chemotherapy treatment. In parallel, cell viability assays were performed using a panel of FDA-approved drugs and combination index (CI) values were calculated to evaluate drug synergy with standard chemotherapy. Mechanisms of synergy were investigated using western blot, propidium iodide flow cytometry, and proliferation assays. Taken together, the screens identified that targeting Src, using either siRNA or the small molecule inhibitor dasatinib, enhanced the efficacy of chemotherapy in OAC cells. Further in vitro functional analysis confirmed Src inhibition to be synergistic with standard OAC chemotherapies, 5-fluorouracil (5-FU), and cisplatin (CDDP). In conclusion, a compound screen together with a functional genomic approach identified Src as a potential chemosensitising target in OAC, which could be assessed in a clinical study for poor prognosis OAC patients.

5.
Sci Rep ; 10(1): 18514, 2020 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-33116257

RESUMEN

Paediatric acute myeloid leukaemia (AML) is a heterogeneous disease characterised by genetics and morphology. The introduction of intensive chemotherapy treatments together with patient stratification and supportive therapy has resulted in a moderate improvement in patient prognosis. However, overall survival rates remain unacceptably poor, with only 65% of patients surviving longer than 5 years. Recently age-specific differences in AML have been identified, highlighting the need for tailored treatments for paediatric patients. Combination therapies have the potential to improve patient prognosis, while minimising harmful side-effects. In the laboratory setting, identifying key combinations from large drug libraries can be resource-intensive, prohibiting discovery and translation into the clinic. To minimise redundancy and maximise discovery, we undertook a multiplex screen of 80 apoptotic-inducing agents in paediatric AML pre-clinical models. The screen was designed using an all-pairs testing algorithm, which ensured that all pairs of compounds could be tested, while minimising the number of wells used. We identified a combination of ABT-737, a Bcl-2 family inhibitor and Purvalanol A, a CDK inhibitor, as a potential targeted therapy for AML patients with an MLL rearrangement and an FLT3-ITD. Our approach has the potential to reduce resource-intensity and time associated with the identification of novel combination therapies.


Asunto(s)
Ensayos de Selección de Medicamentos Antitumorales/métodos , Leucemia Mieloide Aguda/tratamiento farmacológico , Adolescente , Algoritmos , Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Compuestos de Bifenilo/farmacología , Línea Celular Tumoral , Niño , Preescolar , Bases de Datos Genéticas , Femenino , Humanos , Leucemia Mieloide Aguda/metabolismo , Masculino , Nitrofenoles/farmacología , Piperazinas/farmacología , Pronóstico , Purinas/farmacología , Inducción de Remisión , Sulfonamidas/farmacología
6.
Gut ; 68(11): 1918-1927, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-30852560

RESUMEN

OBJECTIVE: Current strategies to guide selection of neoadjuvant therapy in oesophageal adenocarcinoma (OAC) are inadequate. We assessed the ability of a DNA damage immune response (DDIR) assay to predict response following neoadjuvant chemotherapy in OAC. DESIGN: Transcriptional profiling of 273 formalin-fixed paraffin-embedded prechemotherapy endoscopic OAC biopsies was performed. All patients were treated with platinum-based neoadjuvant chemotherapy and resection between 2003 and 2014 at four centres in the Oesophageal Cancer Clinical and Molecular Stratification consortium. CD8 and programmed death ligand 1 (PD-L1) immunohistochemical staining was assessed in matched resection specimens from 126 cases. Kaplan-Meier and Cox proportional hazards regression analysis were applied according to DDIR status for recurrence-free survival (RFS) and overall survival (OS). RESULTS: A total of 66 OAC samples (24%) were DDIR positive with the remaining 207 samples (76%) being DDIR negative. DDIR assay positivity was associated with improved RFS (HR: 0.61; 95% CI 0.38 to 0.98; p=0.042) and OS (HR: 0.52; 95% CI 0.31 to 0.88; p=0.015) following multivariate analysis. DDIR-positive patients had a higher pathological response rate (p=0.033), lower nodal burden (p=0.026) and reduced circumferential margin involvement (p=0.007). No difference in OS was observed according to DDIR status in an independent surgery-alone dataset.DDIR-positive OAC tumours were also associated with the presence of CD8+ lymphocytes (intratumoural: p<0.001; stromal: p=0.026) as well as PD-L1 expression (intratumoural: p=0.047; stromal: p=0.025). CONCLUSION: The DDIR assay is strongly predictive of benefit from DNA-damaging neoadjuvant chemotherapy followed by surgical resection and is associated with a proinflammatory microenvironment in OAC.


Asunto(s)
Adenocarcinoma/inmunología , Adenocarcinoma/terapia , Antineoplásicos/uso terapéutico , Daño del ADN/inmunología , Neoplasias Esofágicas/inmunología , Neoplasias Esofágicas/terapia , Esofagectomía , Terapia Neoadyuvante , Adenocarcinoma/mortalidad , Anciano , Antígeno B7-H1 , Linfocitos T CD8-positivos , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Neoplasias Esofágicas/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Tasa de Supervivencia , Resultado del Tratamiento
7.
Brief Bioinform ; 20(5): 1795-1811, 2019 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-30084865

RESUMEN

There has been an exponential growth in the performance and output of sequencing technologies (omics data) with full genome sequencing now producing gigabases of reads on a daily basis. These data may hold the promise of personalized medicine, leading to routinely available sequencing tests that can guide patient treatment decisions. In the era of high-throughput sequencing (HTS), computational considerations, data governance and clinical translation are the greatest rate-limiting steps. To ensure that the analysis, management and interpretation of such extensive omics data is exploited to its full potential, key factors, including sample sourcing, technology selection and computational expertise and resources, need to be considered, leading to an integrated set of high-performance tools and systems. This article provides an up-to-date overview of the evolution of HTS and the accompanying tools, infrastructure and data management approaches that are emerging in this space, which, if used within in a multidisciplinary context, may ultimately facilitate the development of personalized medicine.


Asunto(s)
Investigación Biomédica , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Medicina de Precisión , Nube Computacional , Biología Computacional , Seguridad Computacional , Ética
8.
Oncotarget ; 9(26): 18518-18528, 2018 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-29719622

RESUMEN

BACKGROUND: The current TNM staging system for oesophageal adenocarcinoma (OAC) has limited ability to stratify patients and inform clinical management following neo-adjuvant chemotherapy and surgery. RESULTS: Functional genomic analysis of the gene expression data using Gene Set Enrichment Analysis (GSEA) identified GLUT1 as putative prognostic marker in OAC.In the discovery cohort GLUT1 positivity was observed in 114 patients (80.9%) and was associated with poor overall survival (HR 2.08, 95% CI 1.1-3.94; p=0.024) following multivariate analysis. A prognostic model incorporating GLUT1, CRM and nodal status stratified patients into good, intermediate and poor prognosis groups (p< 0.001) with a median overall survival of 16.6 months in the poorest group.In the validation set 182 patients (69.5%) were GLUT1 positive and the prognostic model separated patients treated with neo-adjuvant chemotherapy and surgery (p<0.001) and surgery alone (p<0.001) into three prognostic groups. PATIENTS AND METHODS: Transcriptional profiling of 60 formalin fixed paraffin-embedded (FFPE) biopsies was performed. GLUT1 immunohistochemical staining was assessed in a discovery cohort of 141 FFPE OAC samples treated with neo-adjuvant chemotherapy and surgery at the Northern Ireland Cancer Centre from 2004-2012. Validation was performed in 262 oesophageal adenocarcinomas collected at four OCCAMS consortium centres. The relationship between GLUT1 staining, T stage, N stage, lymphovascular invasion and circumferential resection margin (CRM) status was assessed and a prognostic model developed using Cox Proportional Hazards. CONCLUSIONS: GLUT1 staining combined with CRM and nodal status identifies a poor prognosis sub-group of OAC patients and is a novel prognostic marker following potentially curative surgical resection.

9.
J Oncol ; 2018: 2937012, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30651729

RESUMEN

The role of PD-L1 as a prognostic and predictive biomarker is an area of great interest. However, there is a lack of consensus on how to deliver PD-L1 as a clinical biomarker. At the heart of this conundrum is the subjective scoring of PD-L1 IHC in most studies to date. Current standard scoring systems involve separation of epithelial and inflammatory cells and find clinical significance in different percentages of expression, e.g., above or below 1%. Clearly, an objective, reproducible and accurate approach to PD-L1 scoring would bring a degree of necessary consistency to this landscape. Using a systematic comparison of technologies and the application of QuPath, a digital pathology platform, we show that high PD-L1 expression is associated with improved clinical outcome in Triple Negative breast cancer in the context of standard of care (SoC) chemotherapy, consistent with previous findings. In addition, we demonstrate for the first time that high PD-L1 expression is also associated with better outcome in ER- disease as a whole including HER2+ breast cancer. We demonstrate the influence of antibody choice on quantification and clinical impact with the Ventana antibody (SP142) providing the most robust assay in our hands. Through sampling different regions of the tumour, we show that tumour rich regions display the greatest range of PD-L1 expression and this has the most clinical significance compared to stroma and lymphoid rich areas. Furthermore, we observe that both inflammatory and epithelial PD-L1 expression are associated with improved survival in the context of chemotherapy. Moreover, as seen with PD-L1 inhibitor studies, a low threshold of PD-L1 expression stratifies patient outcome. This emphasises the importance of using digital pathology and precise biomarker quantitation to achieve accurate and reproducible scores that can discriminate low PD-L1 expression.

11.
Eur Urol ; 72(4): 509-518, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28408174

RESUMEN

BACKGROUND: Approximately 4-25% of patients with early prostate cancer develop disease recurrence following radical prostatectomy. OBJECTIVE: To identify a molecular subgroup of prostate cancers with metastatic potential at presentation resulting in a high risk of recurrence following radical prostatectomy. DESIGN, SETTING, AND PARTICIPANTS: Unsupervised hierarchical clustering was performed using gene expression data from 70 primary resections, 31 metastatic lymph nodes, and 25 normal prostate samples. Independent assay validation was performed using 322 radical prostatectomy samples from four sites with a mean follow-up of 50.3 months. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Molecular subgroups were identified using unsupervised hierarchical clustering. A partial least squares approach was used to generate a gene expression assay. Relationships with outcome (time to biochemical and metastatic recurrence) were analysed using multivariable Cox regression and log-rank analysis. RESULTS AND LIMITATIONS: A molecular subgroup of primary prostate cancer with biology similar to metastatic disease was identified. A 70-transcript signature (metastatic assay) was developed and independently validated in the radical prostatectomy samples. Metastatic assay positive patients had increased risk of biochemical recurrence (multivariable hazard ratio [HR] 1.62 [1.13-2.33]; p=0.0092) and metastatic recurrence (multivariable HR=3.20 [1.76-5.80]; p=0.0001). A combined model with Cancer of the Prostate Risk Assessment post surgical (CAPRA-S) identified patients at an increased risk of biochemical and metastatic recurrence superior to either model alone (HR=2.67 [1.90-3.75]; p<0.0001 and HR=7.53 [4.13-13.73]; p<0.0001, respectively). The retrospective nature of the study is acknowledged as a potential limitation. CONCLUSIONS: The metastatic assay may identify a molecular subgroup of primary prostate cancers with metastatic potential. PATIENT SUMMARY: The metastatic assay may improve the ability to detect patients at risk of metastatic recurrence following radical prostatectomy. The impact of adjuvant therapies should be assessed in this higher-risk population.


Asunto(s)
Biomarcadores de Tumor/genética , Escisión del Ganglio Linfático , Prostatectomía , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/cirugía , Transcriptoma , Análisis por Conglomerados , Predisposición Genética a la Enfermedad , Humanos , Análisis de los Mínimos Cuadrados , Escisión del Ganglio Linfático/efectos adversos , Metástasis Linfática , Masculino , Análisis Multivariante , Fenotipo , Modelos de Riesgos Proporcionales , Prostatectomía/efectos adversos , Neoplasias de la Próstata/patología , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
12.
Nucleic Acids Res ; 44(17): e137, 2016 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-27353327

RESUMEN

Here, we describe gene expression compositional assignment (GECA), a powerful, yet simple method based on compositional statistics that can validate the transfer of prior knowledge, such as gene lists, into independent data sets, platforms and technologies. Transcriptional profiling has been used to derive gene lists that stratify patients into prognostic molecular subgroups and assess biomarker performance in the pre-clinical setting. Archived public data sets are an invaluable resource for subsequent in silico validation, though their use can lead to data integration issues. We show that GECA can be used without the need for normalising expression levels between data sets and can outperform rank-based correlation methods. To validate GECA, we demonstrate its success in the cross-platform transfer of gene lists in different domains including: bladder cancer staging, tumour site of origin and mislabelled cell lines. We also show its effectiveness in transferring an epithelial ovarian cancer prognostic gene signature across technologies, from a microarray to a next-generation sequencing setting. In a final case study, we predict the tumour site of origin and histopathology of epithelial ovarian cancer cell lines. In particular, we identify and validate the commonly-used cell line OVCAR-5 as non-ovarian, being gastrointestinal in origin. GECA is available as an open-source R package.


Asunto(s)
Bases de Datos Genéticas , Neoplasias Glandulares y Epiteliales/genética , Neoplasias Ováricas/genética , Coloración y Etiquetado , Transcripción Genética , Carcinoma Epitelial de Ovario , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Estadificación de Neoplasias , Neoplasias Glandulares y Epiteliales/patología , Neoplasias Ováricas/patología , Pronóstico , Estadística como Asunto
13.
Clin Cancer Res ; 22(1): 230-242, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26283684

RESUMEN

PURPOSE: EphA2, a member of the Eph receptor tyrosine kinases family, is an important regulator of tumor initiation, neovascularization, and metastasis in a wide range of epithelial and mesenchymal cancers; however, its role in colorectal cancer recurrence and progression is unclear. EXPERIMENTAL DESIGN: EphA2 expression was determined by immunohistochemistry in stage II/III colorectal tumors (N = 338), and findings correlated with clinical outcome. The correlation between EphA2 expression and stem cell markers CD44 and Lgr5 was examined. The role of EphA2 in migration/invasion was assessed using a panel of KRAS wild-type (WT) and mutant (MT) parental and invasive colorectal cancer cell line models. RESULTS: Colorectal tumors displayed significantly higher expression levels of EphA2 compared with matched normal tissue, which positively correlated with high CD44 and Lgr5 expression levels. Moreover, high EphA2 mRNA and protein expression were found to be associated with poor overall survival in stage II/III colorectal cancer tissues, in both univariate and multivariate analyses. Preclinically, we found that EphA2 was highly expressed in KRASMT colorectal cancer cells and that EphA2 levels are regulated by the KRAS-driven MAPK and RalGDS-RalA pathways. Moreover, EphA2 levels were elevated in several invasive daughter cell lines, and downregulation of EphA2 using RNAi or recombinant EFNA1 suppressed migration and invasion of KRASMT colorectal cancer cells. CONCLUSIONS: These data show that EpHA2 is a poor prognostic marker in stage II/III colorectal cancer, which may be due to its ability to promote cell migration and invasion, providing support for the further investigation of EphA2 as a novel prognostic biomarker and therapeutic target.


Asunto(s)
Neoplasias Colorrectales/genética , Neoplasias Colorrectales/mortalidad , Expresión Génica , Receptor EphA2/genética , Biomarcadores de Tumor , Línea Celular Tumoral , Movimiento Celular/genética , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Humanos , Estimación de Kaplan-Meier , Invasividad Neoplásica , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Receptor EphA2/metabolismo , Reproducibilidad de los Resultados , Transducción de Señal , Proteínas de Unión al GTP ral/metabolismo , Factor de Intercambio de Guanina Nucleótido ral/metabolismo , Proteínas ras/metabolismo
15.
Nat Commun ; 6: 7736, 2015 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-26198641

RESUMEN

Prostate cancer (PCa) is the most prevalent cancer in men. Hyperactive STAT3 is thought to be oncogenic in PCa. However, targeting of the IL-6/STAT3 axis in PCa patients has failed to provide therapeutic benefit. Here we show that genetic inactivation of Stat3 or IL-6 signalling in a Pten-deficient PCa mouse model accelerates cancer progression leading to metastasis. Mechanistically, we identify p19(ARF) as a direct Stat3 target. Loss of Stat3 signalling disrupts the ARF-Mdm2-p53 tumour suppressor axis bypassing senescence. Strikingly, we also identify STAT3 and CDKN2A mutations in primary human PCa. STAT3 and CDKN2A deletions co-occurred with high frequency in PCa metastases. In accordance, loss of STAT3 and p14(ARF) expression in patient tumours correlates with increased risk of disease recurrence and metastatic PCa. Thus, STAT3 and ARF may be prognostic markers to stratify high from low risk PCa patients. Our findings challenge the current discussion on therapeutic benefit or risk of IL-6/STAT3 inhibition.


Asunto(s)
Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Interleucina-6/metabolismo , Neoplasias de la Próstata/metabolismo , Factor de Transcripción STAT3/metabolismo , Animales , Línea Celular , Progresión de la Enfermedad , Genes p16 , Humanos , Interleucina-6/genética , Masculino , Ratones , Ratones Transgénicos , Neoplasias Experimentales , Fosfohidrolasa PTEN/genética , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Factor de Transcripción STAT3/genética , Proteína p53 Supresora de Tumor/metabolismo
16.
Scand J Gastroenterol ; 50(8): 975-84, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25861707

RESUMEN

OBJECTIVES: Patients with celiac disease (CD) are at increased risk of osteoporosis and compromised B-vitamin status. Emerging evidence supports a beneficial role of folate and the metabolically related B-vitamins in bone health in generally healthy adults, but no previous study has investigated this in CD patients. The aim of the current study was to examine the relationship of folate, vitamins B12, B6 and B2 (riboflavin), and the related metabolite homocysteine, with bone mineral density (BMD) in CD patients. MATERIALS AND METHODS: Of the 400 treated adult CD patients invited to participate, 110 responded and met the eligibility criteria for study participation. BMD was measured using dual energy X-ray absorptiometry scanning at the lumbar spine (L1-L4), femoral neck, and total hip sites. Biomarker status of the relevant B-vitamins and homocysteine, and dietary B-vitamin intakes, were measured. RESULTS: The significant predictors of low BMD were increasing age (B = 0.080, p < 0.001) and decreasing weight (B = 0.072, p = 0.004), whereas no significant relationship with serum 25-hydroxyvitamin D (B = 0.093, p = 0.928) was observed. Following adjustment for these predictors, serum vitamin B12 (but no other B-vitamin biomarker) was found to be a significant determinant of BMD at the femoral neck (ß = 0.416, p = 0.011) and total hip (ß = 0.327, p = 0.049) in men only. No significant relationships were found between any of the B-vitamin biomarkers investigated and BMD (at any measured site) in women. CONCLUSION: These findings add to current evidence suggesting a potential role of vitamin B12 in BMD, particularly in men, and show such a relationship for the first time in CD patients.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Enfermedad Celíaca/complicaciones , Osteoporosis/sangre , Vitamina B 12/sangre , Complejo Vitamínico B/uso terapéutico , Vitamina D/análogos & derivados , Absorciometría de Fotón , Adulto , Anciano , Biomarcadores , Femenino , Ácido Fólico/uso terapéutico , Humanos , Irlanda , Vértebras Lumbares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Osteoporosis/diagnóstico por imagen , Ingesta Diaria Recomendada , Factores Sexuales , Vitamina D/sangre , Adulto Joven
17.
Mol Oncol ; 9(6): 1234-40, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25814194

RESUMEN

Modern cancer research on prognostic and predictive biomarkers demands the integration of established and emerging high-throughput technologies. However, these data are meaningless unless carefully integrated with patient clinical outcome and epidemiological information. Integrated datasets hold the key to discovering new biomarkers and therapeutic targets in cancer. We have developed a novel approach and set of methods for integrating and interrogating phenomic, genomic and clinical data sets to facilitate cancer biomarker discovery and patient stratification. Applied to a known paradigm, the biological and clinical relevance of TP53, PICan was able to recapitulate the known biomarker status and prognostic significance at a DNA, RNA and protein levels.


Asunto(s)
Biomarcadores de Tumor , Bases de Datos Genéticas , Genómica , Neoplasias , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología
18.
Clin Cancer Res ; 20(1): 164-75, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-24170546

RESUMEN

PURPOSE: Despite the use of 5-fluorouracil (5-FU)-based adjuvant treatments, a large proportion of patients with high-risk stage II/III colorectal cancer will relapse. Thus, novel therapeutic strategies are needed for early-stage colorectal cancer. Residual micrometastatic disease from the primary tumor is a major cause of patient relapse. EXPERIMENTAL DESIGN: To model colorectal cancer tumor cell invasion/metastasis, we have generated invasive (KRASMT/KRASWT/+chr3/p53-null) colorectal cancer cell subpopulations. Receptor tyrosine kinase (RTK) screens were used to identify novel proteins that underpin the migratory/invasive phenotype. Migration/invasion was assessed using the XCELLigence system. Tumors from patients with early-stage colorectal cancer (N = 336) were examined for AXL expression. RESULTS: Invasive colorectal cancer cell subpopulations showed a transition from an epithelial-to-mesenchymal like phenotype with significant increases in migration, invasion, colony-forming ability, and an attenuation of EGF receptor (EGFR)/HER2 autocrine signaling. RTK arrays showed significant increases in AXL levels in all invasive sublines. Importantly, 5-FU treatment resulted in significantly increased migration and invasion, and targeting AXL using pharmacologic inhibition or RNA interference (RNAi) approaches suppressed basal and 5-FU-induced migration and invasion. Significantly, high AXL mRNA and protein expression were found to be associated with poor overall survival in early-stage colorectal cancer tissues. CONCLUSIONS: We have identified AXL as a poor prognostic marker and important mediator of cell migration/invasiveness in colorectal cancer. These findings provide support for the further investigation of AXL as a novel prognostic biomarker and therapeutic target in colorectal cancer, in particular in the adjuvant disease in which EGFR/VEGF-targeted therapies have failed.


Asunto(s)
Adenocarcinoma/metabolismo , Antineoplásicos/farmacología , Biomarcadores de Tumor/fisiología , Neoplasias Colorrectales/metabolismo , Recurrencia Local de Neoplasia/metabolismo , Proteínas Proto-Oncogénicas/fisiología , Proteínas Tirosina Quinasas Receptoras/fisiología , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Anciano , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Progresión de la Enfermedad , Femenino , Fluorouracilo/farmacología , Expresión Génica , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Invasividad Neoplásica , Recurrencia Local de Neoplasia/prevención & control , Estadificación de Neoplasias , Compuestos Organoplatinos/farmacología , Oxaliplatino , Pronóstico , Modelos de Riesgos Proporcionales , Tirosina Quinasa del Receptor Axl
19.
Nucleic Acids Res ; 41(18): 8601-14, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23863842

RESUMEN

Here, we show for the first time, that the familial breast/ovarian cancer susceptibility gene BRCA1 activates the Notch pathway in breast cells by transcriptional upregulation of Notch ligands and receptors in both normal and cancer cells. We demonstrate through chromatin immunoprecipitation assays that BRCA1 is localized to a conserved intronic enhancer region within the Notch ligand Jagged-1 (JAG1) gene, an event requiring ΔNp63. We propose that this BRCA1/ΔNp63-mediated induction of JAG1 may be important the regulation of breast stem/precursor cells, as knockdown of all three proteins resulted in increased tumoursphere growth and increased activity of stem cell markers such as Aldehyde Dehydrogenase 1 (ALDH1). Knockdown of Notch1 and JAG1 phenocopied BRCA1 knockdown resulting in the loss of Estrogen Receptor-α (ER-α) expression and other luminal markers. A Notch mimetic peptide could activate an ER-α promoter reporter in a BRCA1-dependent manner, whereas Notch inhibition using a γ-secretase inhibitor reversed this process. We demonstrate that inhibition of Notch signalling resulted in decreased sensitivity to the anti-estrogen drug Tamoxifen but increased expression of markers associated with basal-like breast cancer. Together, these findings suggest that BRCA1 transcriptional upregulation of Notch signalling is a key event in the normal differentiation process in breast tissue.


Asunto(s)
Proteína BRCA1/fisiología , Neoplasias de la Mama/genética , Mama/metabolismo , Receptores Notch/genética , Animales , Mama/citología , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Proteínas de Unión al Calcio/genética , Diferenciación Celular , Línea Celular , Células Madre Embrionarias/metabolismo , Antagonistas de Estrógenos/farmacología , Femenino , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Proteína Jagged-1 , Células MCF-7 , Proteínas de la Membrana/genética , Ratones , Receptor Notch1/genética , Receptores Notch/biosíntesis , Receptores Notch/metabolismo , Proteínas Serrate-Jagged , Transducción de Señal/genética , Tamoxifeno/farmacología , Factores de Transcripción/fisiología , Transcripción Genética , Proteínas Supresoras de Tumor/fisiología , Regulación hacia Arriba
20.
PLoS One ; 8(6): e66902, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23840550

RESUMEN

The advent of next generation sequencing technologies (NGS) has expanded the area of genomic research, offering high coverage and increased sensitivity over older microarray platforms. Although the current cost of next generation sequencing is still exceeding that of microarray approaches, the rapid advances in NGS will likely make it the platform of choice for future research in differential gene expression. Connectivity mapping is a procedure for examining the connections among diseases, genes and drugs by differential gene expression initially based on microarray technology, with which a large collection of compound-induced reference gene expression profiles have been accumulated. In this work, we aim to test the feasibility of incorporating NGS RNA-Seq data into the current connectivity mapping framework by utilizing the microarray based reference profiles and the construction of a differentially expressed gene signature from a NGS dataset. This would allow for the establishment of connections between the NGS gene signature and those microarray reference profiles, alleviating the associated incurring cost of re-creating drug profiles with NGS technology. We examined the connectivity mapping approach on a publicly available NGS dataset with androgen stimulation of LNCaP cells in order to extract candidate compounds that could inhibit the proliferative phenotype of LNCaP cells and to elucidate their potential in a laboratory setting. In addition, we also analyzed an independent microarray dataset of similar experimental settings. We found a high level of concordance between the top compounds identified using the gene signatures from the two datasets. The nicotine derivative cotinine was returned as the top candidate among the overlapping compounds with potential to suppress this proliferative phenotype. Subsequent lab experiments validated this connectivity mapping hit, showing that cotinine inhibits cell proliferation in an androgen dependent manner. Thus the results in this study suggest a promising prospect of integrating NGS data with connectivity mapping.


Asunto(s)
Perfilación de la Expresión Génica , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , Análisis de Secuencia de ARN , Línea Celular Tumoral , Humanos , Masculino , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología
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