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1.
Reprod Biomed Online ; 45(6): 1105-1117, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36117079

RESUMEN

RESEARCH QUESTION: Can better methods be developed to evaluate the performance and characteristics of an artificial intelligence model for evaluating the likelihood of clinical pregnancy based on analysis of day-5 blastocyst-stage embryos, such that performance evaluation more closely reflects clinical use in IVF procedures, and correlations with known features of embryo quality are identified? DESIGN: De-identified images were provided retrospectively or collected prospectively by IVF clinics using the artificial intelligence model in clinical practice. A total of 9359 images were provided by 18 IVF clinics across six countries, from 4709 women who underwent IVF between 2011 and 2021. Main outcome measures included clinical pregnancy outcome (fetal heartbeat at first ultrasound scan), embryo morphology score, and/or pre-implantation genetic testing for aneuploidy (PGT-A) results. RESULTS: A positive linear correlation of artificial intelligence scores with pregnancy outcomes was found, and up to a 12.2% reduction in time to pregnancy (TTP) was observed when comparing the artificial intelligence model with standard morphological grading methods using a novel simulated cohort ranking method. Artificial intelligence scores were significantly correlated with known morphological features of embryo quality based on the Gardner score, and with previously unknown morphological features associated with embryo ploidy status, including chromosomal abnormalities indicative of severity when considering embryos for transfer during IVF. CONCLUSION: Improved methods for evaluating artificial intelligence for embryo selection were developed, and advantages of the artificial intelligence model over current grading approaches were highlighted, strongly supporting the use of the artificial intelligence model in a clinical setting.


Asunto(s)
Inteligencia Artificial , Blastocisto , Femenino , Embarazo , Humanos , Estudios Retrospectivos , Implantación del Embrión , Aneuploidia , Fertilización In Vitro
2.
IUBMB Life ; 65(12): 999-1011, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24323942

RESUMEN

The mechanisms by which cells control their growth and behavioral identities are complex and require adaptability to environmental changes. Transcription factors act as master controllers of many of these pivotal points through their ability to influence the expression of many thousands of downstream genes, and increasingly research is showing that transcription factor regulation of target genes can change in response to environmental stimuli and cell type such that their function is not prescribed but rather context-dependent. Krüppel like factor 5 (KLF5) is an example of such a transcription factor, where evidence of disparate effects on cell growth and differentiation in normal and transformed tissue are clear. Here we present and discuss the literature covering the differential roles of KLF5 in particular tissues and cancer states, and the mechanisms by which these differences are effected through the regulation of KLF5 protein function in response to different cellular states and the direct effect on target gene expression.


Asunto(s)
Transformación Celular Neoplásica/metabolismo , Regulación de la Expresión Génica , Factores de Transcripción de Tipo Kruppel/fisiología , Animales , Proliferación Celular , Supervivencia Celular , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Oncogenes , Proteínas Supresoras de Tumor/fisiología
3.
Oncogene ; 40(13): 2367-2381, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33658627

RESUMEN

Histone deacetylase (HDAC) inhibitors are effective in MYCN-driven cancers, because of a unique need for HDAC recruitment by the MYCN oncogenic signal. However, HDAC inhibitors are much more effective in combination with other anti-cancer agents. To identify novel compounds which act synergistically with HDAC inhibitor, such as suberanoyl hydroxamic acid (SAHA), we performed a cell-based, high-throughput drug screen of 10,560 small molecule compounds from a drug-like diversity library and identified a small molecule compound (SE486-11) which synergistically enhanced the cytotoxic effects of SAHA. Effects of drug combinations on cell viability, proliferation, apoptosis and colony forming were assessed in a panel of neuroblastoma cell lines. Treatment with SAHA and SE486-11 increased MYCN ubiquitination and degradation, and markedly inhibited tumorigenesis in neuroblastoma xenografts, and, MYCN transgenic zebrafish and mice. The combination reduced ubiquitin-specific protease 5 (USP5) levels and increased unanchored polyubiquitin chains. Overexpression of USP5 rescued neuroblastoma cells from the cytopathic effects of the combination and reduced unanchored polyubiquitin, suggesting USP5 is a therapeutic target of the combination. SAHA and SE486-11 directly bound to USP5 and the drug combination exhibited a 100-fold higher binding to USP5 than individual drugs alone in microscale thermophoresis assays. MYCN bound to the USP5 promoter and induced USP5 gene expression suggesting that USP5 and MYCN expression created a forward positive feedback loop in neuroblastoma cells. Thus, USP5 acts as an oncogenic cofactor with MYCN in neuroblastoma and the novel combination of HDAC inhibitor with SE486-11 represents a novel therapeutic approach for the treatment of MYCN-driven neuroblastoma.


Asunto(s)
Carcinogénesis/efectos de los fármacos , Inhibidores de Histona Desacetilasas/farmacología , Proteína Proto-Oncogénica N-Myc/genética , Neuroblastoma/tratamiento farmacológico , Proteasas Ubiquitina-Específicas/genética , Proteínas de Pez Cebra/genética , Animales , Animales Modificados Genéticamente/genética , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Xenoinjertos , Humanos , Ratones , Neuroblastoma/genética , Neuroblastoma/patología , Bibliotecas de Moléculas Pequeñas/farmacología , Vorinostat/farmacología , Pez Cebra/genética
5.
J Leukoc Biol ; 80(2): 433-47, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16769770

RESUMEN

Mechanisms controlling the balance between proliferation and self-renewal versus growth suppression and differentiation during normal and leukemic myelopoiesis are not understood. We have used the bi-potent FDB1 myeloid cell line model, which is responsive to myelopoietic cytokines and activated mutants of the granulocyte macrophage-colony stimulating factor (GM-CSF) receptor, having differential signaling and leukemogenic activity. This model is suited to large-scale gene-profiling, and we have used a factorial time-course design to generate a substantial and powerful data set. Linear modeling was used to identify gene-expression changes associated with continued proliferation, differentiation, or leukemic receptor signaling. We focused on the changing transcription factor profile, defined a set of novel genes with potential to regulate myeloid growth and differentiation, and demonstrated that the FDB1 cell line model is responsive to forced expression of oncogenes identified in this study. We also identified gene-expression changes associated specifically with the leukemic GM-CSF receptor mutant, V449E. Signaling from this receptor mutant down-regulates CCAAT/enhancer-binding protein alpha (C/EBPalpha) target genes and generates changes characteristic of a specific acute myeloid leukemia signature, defined previously by gene-expression profiling and associated with C/EBPalpha mutations.


Asunto(s)
Perfilación de la Expresión Génica , Regulación Leucémica de la Expresión Génica , Modelos Biológicos , Mielopoyesis/genética , Receptores de Factores de Crecimiento/genética , Transducción de Señal , Animales , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Diferenciación Celular , Línea Celular , Proliferación Celular , Humanos , Ratones , Familia de Multigenes
6.
J Proteomics ; 96: 1-12, 2014 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-24200836

RESUMEN

The majority of patients diagnosed with neuroblastoma present with aggressive disease. Improved detection of neuroblastoma cancer cells following initial therapy may help in stratifying patient outcome and monitoring for relapse. To identify potential plasma biomarkers, we utilised a liquid chromatography-tandem mass spectrometry-based proteomics approach to detect differentially-expressed proteins in serum from TH-MYCN mice. TH-MYCN mice carry multiple copies of the human MYCN oncogene in the germline and homozygous mice for the transgene develop neuroblastoma in a manner resembling the human disease. The abundance of plasma proteins was measured over the course of disease initiation and progression. A list of 86 candidate plasma biomarkers was generated. Pathway analysis identified significant association of these proteins with genes involved in the complement system. One candidate, complement C3 protein, was significantly enriched in the plasma of TH-MYCN(+/+) mice at both 4 and 6weeks of age, and was found to be elevated in a cohort of human neuroblastoma plasma samples, compared to healthy subjects. In conclusion, we have demonstrated the suitability of the TH-MYCN(+/+) mouse model of neuroblastoma for identification of novel disease biomarkers in humans, and have identified Complement C3 as a candidate plasma biomarker for measuring disease state in neuroblastoma patients. BIOLOGICAL SIGNIFICANCE: This study has utilised a unique murine model which develops neuroblastoma tumours that are biologically indistinguishable from human neuroblastoma. This animal model has effectively allowed the identification of plasma proteins which may serve as potential biomarkers of neuroblastoma. Furthermore, the label-free ion count quantitation technique which was used displays significant benefits as it is less labour intensive, feasible and accurate. We have been able to successfully validate this approach by confirming the differential abundance of two different plasma proteins. In addition, we have been able to confirm that the candidate biomarker Complement C3, is more abundant in the plasma of human neuroblastoma patient plasma samples when compared to healthy counterparts. Overall we have demonstrated that this approach can be potentially useful in the identification of biomarker candidates, and that further validation of the candidates may lead to the discovery of novel, clinically useful diagnostic tools in the detection of sub-clinical neuroblastoma.


Asunto(s)
Biomarcadores/sangre , Complemento C3/metabolismo , Neoplasias Experimentales/sangre , Neuroblastoma/sangre , Adulto , Animales , Preescolar , Femenino , Humanos , Recién Nacido , Masculino , Ratones , Ratones Transgénicos
7.
Leuk Res ; 36(1): 110-6, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21993314

RESUMEN

Krüppel-like factor 5 (KLF5) has been implicated as a tumor suppressor in various solid tumors such as breast and prostate, and recent studies have demonstrated a role for this protein in neutrophil differentiation of acute promyelocytic leukemia cells in response to ATRA. Here, we show that KLF5 expression increases during primary granulocyte differentiation and that expression of KLF5 is a requirement for granulocyte differentiation of 32D cells. In AML, we show that KLF5 mRNA expression levels are reduced in multiple French-American-British subtypes compared to normal controls, and also in leukemic stem cells relative to normal hematopoietic stem cells. We demonstrate that in selected AML cases, reduced expression is associated with hypermethylation of the KLF5 locus in the proximal promoter and/or intron 1, suggesting that this may represent a Class II genetic lesion in the development of AML.


Asunto(s)
Metilación de ADN , Silenciador del Gen , Granulocitos/metabolismo , Factores de Transcripción de Tipo Kruppel/genética , Leucemia Mieloide Aguda/genética , Línea Celular Tumoral , Metilación de ADN/fisiología , Perfilación de la Expresión Génica , Regulación Leucémica de la Expresión Génica , Silenciador del Gen/fisiología , Sitios Genéticos , Granulocitos/patología , Humanos , Factores de Transcripción de Tipo Kruppel/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Análisis por Micromatrices , Regiones Promotoras Genéticas/genética , Regulación hacia Arriba
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