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1.
Am J Pathol ; 194(7): 1262-1271, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38537933

RESUMEN

Hepatocellular carcinoma (HCC) is one of the most fatal malignancies. Early diagnosis of HCC is crucial in reducing the risk for mortality. This study analyzed a panel of nine fusion transcripts in serum samples from 61 patients with HCC and 75 patients with non-HCC conditions, using TaqMan real-time quantitative RT-PCR. Seven of the nine fusions frequently detected in patients with HCC included: MAN2A1-FER (100%), SLC45A2-AMACR (62.3%), ZMPSTE24-ZMYM4 (62.3%), PTEN-NOLC1 (57.4%), CCNH-C5orf30 (55.7%), STAMBPL1-FAS (26.2%), and PCMTD1-SNTG1 (16.4%). Machine-learning models were constructed based on serum fusion-gene levels to predict HCC in the training cohort, using the leave-one-out cross-validation approach. One machine-learning model, called the four fusion genes logistic regression model (MAN2A1-FER≤40, CCNH-C5orf30≤38, SLC45A2-AMACR≤41, and PTEN-NOLC1≤40), produced accuracies of 91.5% and 83.3% in the training and testing cohorts, respectively. When serum α-fetal protein level was incorporated into the machine-learning model, a two fusion gene (MAN2A1-FER≤40, CCNH-C5orf30≤38) + α-fetal protein logistic regression model was found to generate an accuracy of 94.8% in the training cohort. The same model resulted in 95% accuracy in both the testing and combined cohorts. Cancer treatment was associated with reduced levels of most of the serum fusion transcripts. Serum fusion-gene machine-learning models may serve as important tools in screening for HCC and in monitoring the impact of HCC treatment.


Asunto(s)
Biomarcadores de Tumor , Carcinoma Hepatocelular , Neoplasias Hepáticas , Aprendizaje Automático , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/sangre , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/sangre , Masculino , Femenino , Persona de Mediana Edad , Anciano , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/sangre , Adulto , Proteínas de Fusión Oncogénica/genética
2.
Am J Pathol ; 193(4): 392-403, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36681188

RESUMEN

Prostate cancer remains one of the most fatal malignancies in men in the United States. Predicting the course of prostate cancer is challenging given that only a fraction of prostate cancer patients experience cancer recurrence after radical prostatectomy or radiation therapy. This study examined the expressions of 14 fusion genes in 607 prostate cancer samples from the University of Pittsburgh, Stanford University, and the University of Wisconsin-Madison. The profiling of 14 fusion genes was integrated with Gleason score of the primary prostate cancer and serum prostate-specific antigen level to develop machine-learning models to predict the recurrence of prostate cancer after radical prostatectomy. Machine-learning algorithms were developed by analysis of the data from the University of Pittsburgh cohort as a training set using the leave-one-out cross-validation method. These algorithms were then applied to the data set from the combined Stanford/Wisconsin cohort (testing set). The results showed that the addition of fusion gene profiling consistently improved the prediction accuracy rate of prostate cancer recurrence by Gleason score, serum prostate-specific antigen level, or a combination of both. These improvements occurred in both the training and testing cohorts and were corroborated by multiple models.


Asunto(s)
Antígeno Prostático Específico , Neoplasias de la Próstata , Masculino , Humanos , Antígeno Prostático Específico/genética , Recurrencia Local de Neoplasia/patología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata/patología , Próstata/patología , Prostatectomía , Pronóstico
3.
Opt Express ; 28(3): 3136-3146, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-32121987

RESUMEN

We theoretically propose a dual-channel bistable switch based on a monolayer Z-shaped graphene nanoribbon nanoresonator (NR) coupled to a metal nanoparticle (MNP). We show that the bistable nonlinear absorption response can be realized due to a competition and combination of the exciton-plasmon and exciton-phonon interactions. We map out two-dimensional and three-dimensional bistability phase diagrams, which reveal clearly the dynamical evolution of the roles played by these two interactions in managing optical bistability (OB) at all stages. Specifically, the bistable switch proposed can be controlled via a single channel or dual channels by only adjusting the intensity or frequency of the pump field. In/outside these channels, the switch will be turned on/off. The results obtained here not only can be employed to measure precisely the distance between the MNP and the NR but also provide promising applications in optical switching and optical storage.

4.
Gastroenterology ; 153(4): 1120-1132.e15, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28245430

RESUMEN

BACKGROUND & AIMS: Human tumors and liver cancer cell lines express the product of a fusion between the first 13 exons in the mannosidase α class 2A member 1 gene (MAN2A1) and the last 6 exons in the FER tyrosine kinase gene (FER), called MAN2A1-FER. We investigated whether MAN2A1-FER is expressed by human liver tumors and its role in liver carcinogenesis. METHODS: We performed reverse transcription polymerase chain reaction analyses of 102 non-small cell lung tumors, 61 ovarian tumors, 70 liver tumors, 156 glioblastoma multiform samples, 27 esophageal adenocarcinomas, and 269 prostate cancer samples, as well as 10 nontumor liver tissues and 20 nontumor prostate tissues, collected at the University of Pittsburgh. We also measured expression by 15 human cancer cell lines. We expressed a tagged form of MAN2A1-FER in NIH3T3 and HEP3B (liver cancer) cells; Golgi were isolated for analysis. MAN2A1-FER was also overexpressed in PC3 or DU145 (prostate cancer), NIH3T3 (fibroblast), H23 (lung cancer), and A-172 (glioblastoma multiforme) cell lines and knocked out in HUH7 (liver cancer) cells. Cells were analyzed for proliferation and in invasion assays, and/or injected into flanks of severe combined immunodeficient mice; xenograft tumor growth and metastasis were assessed. Mice with hepatic deletion of PTEN were given tail-vein injections of MAN2A1-FER. RESULTS: We detected MAN2A1-FER messenger RNA and fusion protein (114 kD) in the hepatocellular carcinoma cell line HUH7, as well as in liver tumors, esophageal adenocarcinoma, glioblastoma multiforme, prostate tumors, non-small cell lung tumors, and ovarian tumors, but not nontumor prostate or liver tissues. MAN2A1-FER protein retained the signal peptide for Golgi localization from MAN2A1 and translocated from the cytoplasm to Golgi in cancer cell lines. MAN2A1-FER had tyrosine kinase activity almost 4-fold higher than that of wild-type FER, and phosphorylated the epidermal growth factor receptor at tyrosine 88 in its N-terminus. Expression of MAN2A1-FER in 4 cell lines led to epidermal growth factor receptor activation of BRAF, MEK, and AKT; HUH7 cells with MAN2A1-FER knockout had significant decreases in phosphorylation of these proteins. Cell lines that expressed MAN2A1-FER had increased proliferation, colony formation, and invasiveness and formed larger (>2-fold) xenograft tumors in mice, with more metastases, than cells not expressing the fusion protein. HUH7 cells with MAN2A1-FER knockout formed smaller xenograft tumors, with fewer metastases, than control HUH7 cells. HUH7, A-172, and PC3 cells that expressed MAN2A1-FER were about 2-fold more sensitive to the FER kinase inhibitor crizotinib and the epidermal growth factor receptor kinase inhibitor canertinib; these drugs slowed growth of xenograft tumors from MAN2A1-FER cells and prevented their metastasis in mice. Hydrodynamic tail-vein injection of MAN2A1-FER resulted in rapid development of liver cancer in mice with hepatic disruption of Pten. CONCLUSIONS: Many human tumor types and cancer cell lines express the MAN2A1-FER fusion, which increases proliferation and invasiveness of cancer cell lines and has liver oncogenic activity in mice.


Asunto(s)
Antineoplásicos/farmacología , Transformación Celular Neoplásica/genética , Fusión Génica , Neoplasias Hepáticas/genética , Proteínas de Fusión Oncogénica/genética , Oncogenes , Proteínas Tirosina Quinasas/genética , alfa-Manosidasa/genética , Animales , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Crizotinib , Relación Dosis-Respuesta a Droga , Activación Enzimática , Receptores ErbB/genética , Receptores ErbB/metabolismo , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Aparato de Golgi/enzimología , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/enzimología , Neoplasias Hepáticas/patología , Ratones , Ratones Noqueados , Ratones SCID , Morfolinas/farmacología , Células 3T3 NIH , Invasividad Neoplásica , Trasplante de Neoplasias , Proteínas de Fusión Oncogénica/antagonistas & inhibidores , Proteínas de Fusión Oncogénica/metabolismo , Fosfohidrolasa PTEN/deficiencia , Fosfohidrolasa PTEN/genética , Fosforilación , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Tirosina Quinasas/metabolismo , Pirazoles/farmacología , Piridinas/farmacología , Interferencia de ARN , Factores de Tiempo , Transfección , Carga Tumoral , alfa-Manosidasa/antagonistas & inhibidores , alfa-Manosidasa/metabolismo
5.
Nanotechnology ; 29(25): 255704, 2018 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-29620534

RESUMEN

We present a study for the impact of exciton-phonon and exciton-plasmon interactions on bistable four-wave mixing (FWM) signals in a metal nanoparticle (MNP)-monolayer MoS2 nanoresonator hybrid system. Via tracing the FWM response we predict that, depending on the excitation conditions and the system parameters, such a system exhibits 'U-shaped' bistable FWM signals. We also map out bistability phase diagrams within the system's parameter space. Especially, we show that compared with the exciton-phonon interaction, a strong exciton-plasmon interaction plays a dominant role in the generation of optical bistability, and the bistable region will be greatly broadened by shortening the distance between the MNP and the monolayer MoS2 nanoresonator. In the weak exciton-plasmon coupling regime, the impact of exciton-phonon interaction on optical bistability will become obvious. The scheme proposed may be used for building optical switches and logic-gate devices for optical computing and quantum information processing.

6.
Sensors (Basel) ; 18(4)2018 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-29649146

RESUMEN

In this study, we propose a real-time pedestrian detection system using a FPGA with a digital image sensor. Comparing with some prior works, the proposed implementation realizes both the histogram of oriented gradients (HOG) and the trained support vector machine (SVM) classification on a FPGA. Moreover, the implementation does not use any external memory or processors to assist the implementation. Although the implementation implements both the HOG algorithm and the SVM classification in hardware without using any external memory modules and processors, the proposed implementation's resource utilization of the FPGA is lower than most of the prior art. The main reasons resulting in the lower resource usage are: (1) simplification in the Getting Bin sub-module; (2) distributed writing and two shift registers in the Cell Histogram Generation sub-module; (3) reuse of each sum of the cell histogram in the Block Histogram Normalization sub-module; and (4) regarding a window of the SVM classification as 105 blocks of the SVM classification. Moreover, compared to Dalal and Triggs's pure software HOG implementation, the proposed implementation's average detection rate is just about 4.05% less, but can achieve a much higher frame rate.

7.
Mol Carcinog ; 56(2): 315-324, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27148859

RESUMEN

Cellular stress response 1 (CSR1) is a tumor suppressor gene that plays an important role in regulating cell death. In this report, we show that the N-terminus of CSR1 interacts with splicing factor 3A, subunit 3 (SF3A3). The SF3A3 binding motif was identified in the region of amino acids 62-91 of CSR1 through cell-free binding analyses. The interaction between CSR1 and SF3A3 led to migration of SF3A3 from nucleus to cytoplasm. The cytoplasmic redistribution of SF3A3 significantly reduced the splicing efficiency of epidermal growth factor receptor and platelet-derived growth factor receptor. Induction of CSR1 or down-regulation of SF3A3 also significantly reduced the splicing activity of oxytocin reporter gene both in vivo and in vitro. Mutant CSR1 that lacks the SF3A3 binding motif contained no RNA splicing regulatory activity, while the peptide corresponding to the SF3A3 binding motif in CSR1 interfered with the wild-type CSR1 mediated inhibition of RNA splicing. Interaction of CSR1 and SF3A3 is essential for CSR1 mediated cell death. To our knowledge, this is the first report demonstrating that RNA splicing is negatively regulated by redistribution of a splicing factor. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Regulación hacia Abajo , Receptores ErbB/genética , Proteínas de Choque Térmico/metabolismo , Empalme del ARN , Receptores del Factor de Crecimiento Derivado de Plaquetas/genética , Ribonucleoproteína Nuclear Pequeña U2/metabolismo , Receptores Depuradores de Clase A/metabolismo , Muerte Celular , Línea Celular , Regulación de la Expresión Génica , Proteínas de Choque Térmico/genética , Humanos , Mutación , Ribonucleoproteína Nuclear Pequeña U2/genética , Receptores Depuradores de Clase A/genética
8.
Opt Express ; 25(21): 25663-25673, 2017 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-29041231

RESUMEN

We perform a theoretical study of the bistable four-wave mixing (FWM) response in a coupled system comprised of a semiconductor quantum dot (SQD) and a photonic crystal (PC) nanocavity in which the SQD is embedded. It is shown that the shape of the FWM spectrum can switch among single-peaked, double-peaked, triple-peaked, and four-peaked arising from the vacuum Rabi splitting and the exciton-nanocavity coupling. Especially, we map out bistability phase diagrams within a parameter subspace of the system, and find that it is easy to turn on or off the bistable FWM response by only adjusting the excitation frequency or the pumping intensity. Our results offer a feasible means for measuring the SQD-PC nanocavity coupling strength and open a new avenue to design optical switches and memories.

9.
Opt Express ; 25(12): 13567-13576, 2017 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-28788900

RESUMEN

We theoretically propose a feasible scheme to advance or slow the propagation of light in a monolayer MoS2 nanoresonator (NR). The scheme allows one to easily turn on or off the fast (superluminal) and slow (subluminal) light effects and switch freely between fast and slow light propagation by only adjusting the frequency or intensity of the pump field. As the exciton interacts strongly with the phonons in MoS2, the slow light effect will appear along with a large dispersion with a very steep negative slope and a sharp absorption peak. Especially, the maximal group velocity index of the slow light in the monolayer MoS2 NR can reach two orders of magnitude larger than that in a carbon nanotube resonator. These results provide a new way to measure the exciton-phonon coupling strength and may prove useful in device applications such as optical switching and optical signal processing.

10.
J Biol Chem ; 290(3): 1404-11, 2015 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-25425645

RESUMEN

Miniature chromosome maintenance 7 (MCM7) is an essential component of DNA replication licensing complex. Recent studies indicate that MCM7 is amplified and overexpressed in a variety of human malignancies. In this report, we show that MCM7 binds SF3B3. The binding motif is located in the N terminus (amino acids 221-248) of MCM7. Knockdown of MCM7 or SF3B3 significantly increased unspliced RNA of epidermal growth factor receptor, platelet-derived growth factor receptor, and c-Met. A dramatic drop of reporter gene expression of the oxytocin exon 1-intron-exon 2-EGFP construct was also identified in SF3B3 and MCM7 knockdown PC3 and DU145 cells. The MCM7 or SF3B3 depleted cell extract failed to splice reporter RNA in in vitro RNA splicing analyses. Knockdown of SF3B3 and MCM7 leads to an increase of cell death of both PC3 and DU145 cells. Such cell death induction is partially rescued by expressing spliced c-Met. To our knowledge, this is the first report suggesting that MCM7 is a critical RNA splicing factor, thus giving significant new insight into the oncogenic activity of this protein.


Asunto(s)
Replicación del ADN , Receptores ErbB/metabolismo , Componente 7 del Complejo de Mantenimiento de Minicromosoma/metabolismo , Proteínas Proto-Oncogénicas c-met/metabolismo , Empalme del ARN , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Apoptosis , Muerte Celular , Línea Celular Tumoral , Epigénesis Genética , Exones , Glutatión Transferasa/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Intrones , Oxitocina/química , Fenotipo , Plásmidos/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , ARN Interferente Pequeño/metabolismo , Receptores Androgénicos/metabolismo , Transducción de Señal , Empalmosomas/metabolismo , Técnicas del Sistema de Dos Híbridos
11.
Am J Pathol ; 185(7): 1834-45, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25963990

RESUMEN

Fusion transcript formation is one of the fundamental mechanisms that drives the development of prostate cancer. Because of the advance of high-throughput parallel sequencing, many fusion transcripts have been discovered. However, the discovery rate of fusion transcripts specific for prostate cancer is lagging behind the discoveries made on chromosome abnormalities of prostate cancer. Recent analyses suggest that many fusion transcripts are present in both benign and cancerous tissues. Some of these fusion transcripts likely represent important components of normal gene expression in cells. It is necessary to identify the criteria and features of fusion transcripts that are specific for cancer. In this review, we discuss optimization of RNA sequencing depth for fusion transcript discovery and the characteristics of fusion transcripts in normal prostate tissues and prostate cancer. We also propose a new classification of cancer-specific fusion transcripts on the basis of their tail gene fusion protein product and the roles that these fusions may play in cancer development.


Asunto(s)
Fusión Génica , Próstata/fisiología , Neoplasias de la Próstata/genética , Fusión Génica/genética , Humanos , Masculino , Fusión de Oncogenes/genética , Neoplasias de la Próstata/clasificación , ARN Mensajero/genética , Análisis de Secuencia de ARN
12.
Am J Pathol ; 185(7): 1991-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25956032

RESUMEN

Cellular stress response 1 (CSR1) is a tumor suppressor gene whose expression was frequently down-regulated in prostate cancer. The mechanism of its down-regulation, however, is not clear. Here, we show that the 3' untranslated region of CSR1 contains a target site of miR-650. High level of miR-650 was found in prostate cancer samples and cell lines. Degradation of miR-650 by specific inhibitor dramatically increased the expression levels of CSR1. Interaction between miR-650 and its target site in the 3' untranslated region was validated through luciferase reporter system. Mutation at the target site completely abrogated the activity of miR-650 on the 3' untranslated region of CSR1. Inhibition of miR-650 reversed the expression suppression of CSR1, suppressed colony formation, and blocked cell cycle entry to the S phase of both PC3 and DU145 cells. Animal model showed significant decrease of tumor volume, rate of metastasis, and mortality of severe combined immunodeficient mice xenografted with PC3 or DU145 cells transformed with inhibitor of miR-650. Our analyses demonstrate that suppression of CSR1 expression is a novel mechanism critical for the oncogenic activity of miR-650.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Proteínas de Choque Térmico/genética , MicroARNs/genética , Neoplasias de la Próstata/genética , Receptores Depuradores de Clase A/genética , Regiones no Traducidas 3'/genética , Anciano , Secuencia de Aminoácidos , Animales , Carcinogénesis/genética , Línea Celular Tumoral , Regulación hacia Abajo , Proteínas de Choque Térmico/inmunología , Humanos , Masculino , Ratones , Persona de Mediana Edad , Datos de Secuencia Molecular , Neoplasias de la Próstata/patología , Estabilidad del ARN , Conejos , Receptores Depuradores de Clase A/inmunología , Análisis de Matrices Tisulares , Regulación hacia Arriba
13.
Am J Pathol ; 184(10): 2840-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25238935

RESUMEN

The mechanisms underlying the potential for aggressive behavior of prostate cancer (PCa) remain elusive. In this study, whole genome and/or transcriptome sequencing was performed on 19 specimens of PCa, matched adjacent benign prostate tissues, matched blood specimens, and organ donor prostates. A set of novel fusion transcripts was discovered in PCa. Eight of these fusion transcripts were validated through multiple approaches. The occurrence of these fusion transcripts was then analyzed in 289 prostate samples from three institutes, with clinical follow-up ranging from 1 to 15 years. The analyses indicated that most patients [69 (91%) of 76] positive for any of these fusion transcripts (TRMT11-GRIK2, SLC45A2-AMACR, MTOR-TP53BP1, LRRC59-FLJ60017, TMEM135-CCDC67, KDM4-AC011523.2, MAN2A1-FER, and CCNH-C5orf30) experienced PCa recurrence, metastases, and/or PCa-specific death after radical prostatectomy. These outcomes occurred in only 37% (58/157) of patients without carrying those fusion transcripts. Three fusion transcripts occurred exclusively in PCa samples from patients who experienced recurrence or PCaerelated death. The formation of these fusion transcripts may be the result of genome recombination. A combination of these fusion transcripts in PCa with Gleason's grading or with nomogram significantly improves the prediction rate of PCa recurrence. Our analyses suggest that formation of these fusion transcripts may underlie the aggressive behavior of PCa.


Asunto(s)
Fusión Génica , Neoplasias de la Próstata/genética , ARN Mensajero/genética , Transcriptoma , Adulto , Anciano , Estudios de Cohortes , Estudios de Seguimiento , Biblioteca de Genes , Humanos , Hibridación Fluorescente in Situ , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Recurrencia Local de Neoplasia , Pronóstico , Próstata/patología , Prostatectomía , Neoplasias de la Próstata/patología , Alineación de Secuencia , Análisis de Secuencia de ADN , Adulto Joven
14.
Am J Pathol ; 183(3): 831-40, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23830872

RESUMEN

Integrin α7 (ITGA7) is a tumor-suppressor gene that is critical for suppressing the growth of malignant tumors; however, the mechanisms allowing ITGA7 to suppress the growth of cancer cells remain unclear. Herein, we show that ITGA7 binds to tissue inhibitor of metalloproteinase 3 (TIMP3) in prostate cancer cells. The ITGA7-TIMP3 binding led to a decreased protein level of tumor necrosis factor α, cytoplasmic translocation of NF-κB, and down-regulation of cyclin D1. These changes led to an accumulation of cells in G0/G1 and a dramatic suppression of cell growth. Knocking down TIMP3 or ITGA7/TIMP3 binding interference largely abrogated the signaling changes induced by ITGA7, whereas a mutant ITGA7 lacking TIMP3 binding activity had no tumor-suppressor activity. Interestingly, knocking down ITGA7 ligand laminin ß1 enhanced ITGA7-TIMP3 signaling and the downstream tumor-suppressor activity, suggesting the existence of a counterbalancing role between extracellular matrix and integrin signaling. As a result, this report demonstrates a novel and critical signaling mechanism of ITGA7, through the TIMP3/NF-κB/cyclin D1 pathway.


Asunto(s)
Antígenos CD/metabolismo , Cadenas alfa de Integrinas/metabolismo , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Inhibidor Tisular de Metaloproteinasa-3/metabolismo , Secuencias de Aminoácidos , Línea Celular Tumoral , Proliferación Celular , Ciclina D1/metabolismo , Regulación hacia Abajo , Humanos , Laminina/metabolismo , Masculino , Unión Proteica , Factor de Transcripción ReIA/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
15.
Am J Pathol ; 182(6): 2028-36, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23583283

RESUMEN

Altered genome methylation is a hallmark of human malignancies. In this study, high-throughput analyses of concordant gene methylation and expression events were performed for 91 human prostate specimens, including prostate tumor (T), matched normal adjacent to tumor (AT), and organ donor (OD). Methylated DNA in genomic DNA was immunoprecipitated with anti-methylcytidine antibodies and detected by Affymetrix human whole genome SNP 6.0 chips. Among the methylated CpG islands, 11,481 islands were found located in the promoter and exon 1 regions of 9295 genes. Genes (7641) were methylated frequently across OD, AT, and T samples, whereas 239 genes were differentially methylated in only T and 785 genes in both AT and T but not OD. Genes with promoter methylation and concordantly suppressed expression were identified. Pathway analysis suggested that many of the methylated genes in T and AT are involved in cell growth and mitogenesis. Classification analysis of the differentially methylated genes in T or OD produced a specificity of 89.4% and a sensitivity of 85.7%. The T and AT groups, however, were only slightly separated by the prediction analysis, indicating a strong field effect. A gene methylation prediction model was shown to predict prostate cancer relapse with sensitivity of 80.0% and specificity of 85.0%. These results suggest methylation patterns useful in predicting clinical outcomes of prostate cancer.


Asunto(s)
Metilación de ADN , Neoplasias de la Próstata/genética , Islas de CpG , ADN de Neoplasias/genética , Genes Relacionados con las Neoplasias , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Pronóstico , Regiones Promotoras Genéticas , Recurrencia , Sensibilidad y Especificidad
16.
Am J Pathol ; 182(3): 796-805, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23313748

RESUMEN

MCM7 is one of the pivotal DNA replication licensing factors in controlling DNA synthesis and cell entry into S phase. Its expression and DNA copy number are some of the most predictive factors for the growth and behavior of human malignancies. In this study, we identified that MCM7 interacts with the receptor for activated protein kinase C 1 (RACK1), a protein kinase C (PKC) adaptor, in vivo and in vitro. The RACK1 binding motif in MCM7 is located at the amino acid 221-248. Knocking down RACK1 significantly reduced MCM7 chromatin association, DNA synthesis, and cell cycle entry into S phase. Activation of PKC by 12-O-tetradecanoylphorbol-13-acetate dramatically decreased MCM7 DNA replication licensing and induced cell growth arrest. Activation of PKC induced redistribution of RACK1 from nucleus to cytoplasm and decreased RACK1-chromatin association. The MCM7 mutant that does not bind RACK1 has no DNA replication licensing or oncogenic transformation activity. As a result, this study demonstrates a novel signaling mechanism that critically controls DNA synthesis and cell cycle progression.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al GTP/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Receptores de Superficie Celular/metabolismo , Línea Celular Tumoral , Proliferación Celular , Transformación Celular Neoplásica , Cromatina/metabolismo , ADN/biosíntesis , Activación Enzimática , Humanos , Componente 7 del Complejo de Mantenimiento de Minicromosoma , Modelos Biológicos , Unión Proteica , Proteína Quinasa C/metabolismo , Receptores de Cinasa C Activada , Fase S
17.
Am J Pathol ; 183(6): 1960-1970, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24113458

RESUMEN

DNA methylation is one of the most important epigenetic mechanisms in regulating gene expression. Genome hypermethylation has been proposed as a critical mechanism in human malignancies. However, whole-genome quantification of DNA methylation of human malignancies has rarely been investigated, and the significance of the genome distribution of CpG methylation is unclear. We performed whole-genome methylation sequencing to investigate the methylation profiles of 13 prostate samples: 5 prostate cancers, 4 matched benign prostate tissues adjacent to tumor, and 4 age-matched organ-donor prostate tissues. Alterations of methylation patterns occurred in prostate cancer and in benign prostate tissues adjacent to tumor, in comparison with age-matched organ-donor prostates. More than 95% alterations of genome methylation occurred in sequences outside CpG islands. Only a small fraction of the methylated CpG islands had any effect on RNA expression. Both intragene and promoter CpG island methylations negatively affected gene expression. However, suppressions of RNA expression did not correlate with levels of CpG island methylation, suggesting that CpG island methylation alone might not be sufficient to shut down gene expression. Motif analysis revealed a consensus sequence containing Sp1 binding motif significantly enriched in the effective CpG islands.


Asunto(s)
Islas de CpG , Metilación de ADN , Genoma Humano , Neoplasias de la Próstata/metabolismo , Transcripción Genética , Anciano , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología
18.
J Pathol ; 230(2): 184-93, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23355073

RESUMEN

Metallothioneins (MTs) are a group of metal binding proteins thought to play a role in the detoxification of heavy metals. Here we showed by microarray and validation analyses that MT1h, a member of MT, is down-regulated in many human malignancies. Low expression of MT1h was associated with poor clinical outcomes in both prostate and liver cancer. We found that the promoter region of MT1h was hypermethylated in cancer and that demethylation of the MT1h promoter reversed the suppression of MT1h expression. Forced expression of MT1h induced cell growth arrest, suppressed colony formation, retarded migration, and reduced invasion. SCID mice with tumour xenografts with inducible MT1h expression had lower tumour volumes as well as fewer metastases and deaths than uninduced controls. MT1h was found to interact with euchromatin histone methyltransferase 1 (EHMT1) and enhanced its methyltransferase activity on histone 3. Knocking down of EHMT1 or a mutation in MT1h that abrogates its interaction with EHMT1 abrogated MT1h tumour suppressor activity. This demonstrates tumour suppressor activity in a heavy metal binding protein that is dependent on activation of histone methylation.


Asunto(s)
Adenocarcinoma/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , Metalotioneína/metabolismo , Neoplasias de la Próstata/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/mortalidad , Adenocarcinoma/secundario , Animales , Línea Celular Transformada , Línea Celular Tumoral , Regulación hacia Abajo , Femenino , Regulación Neoplásica de la Expresión Génica , N-Metiltransferasa de Histona-Lisina/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Metalotioneína/genética , Ratones , Ratones SCID , Análisis por Micromatrices , Pennsylvania/epidemiología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patología , Tasa de Supervivencia , Proteínas Supresoras de Tumor/genética
19.
Elife ; 122024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38206124

RESUMEN

The protein diversity of mammalian cells is determined by arrays of isoforms from genes. Genetic mutation is essential in species evolution and cancer development. Accurate long-read transcriptome sequencing at single-cell level is required to decipher the spectrum of protein expressions in mammalian organisms. In this report, we developed a synthetic long-read single-cell sequencing technology based on LOOPSeq technique. We applied this technology to analyze 447 transcriptomes of hepatocellular carcinoma (HCC) and benign liver from an individual. Through Uniform Manifold Approximation and Projection analysis, we identified a panel of mutation mRNA isoforms highly specific to HCC cells. The evolution pathways that led to the hyper-mutation clusters in single human leukocyte antigen molecules were identified. Novel fusion transcripts were detected. The combination of gene expressions, fusion gene transcripts, and mutation gene expressions significantly improved the classification of liver cancer cells versus benign hepatocytes. In conclusion, LOOPSeq single-cell technology may hold promise to provide a new level of precision analysis on the mammalian transcriptome.


Asunto(s)
Células Artificiales , Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Humanos , Neoplasias Hepáticas/genética , Carcinoma Hepatocelular/genética , Isoformas de Proteínas/genética , Mamíferos
20.
Hepatol Commun ; 8(4)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38497929

RESUMEN

BACKGROUND: Liver cancer is one of the most lethal malignancies for humans. The treatment options for advanced-stage liver cancer remain limited. A new treatment is urgently needed to reduce the mortality of the disease. METHODS: In this report, we developed a technology for mutation site insertion of a suicide gene (herpes simplex virus type 1- thymidine kinase) based on type II CRISPR RNA-guided endonuclease Cas9-mediated genome editing to treat liver cancers. RESULTS: We applied the strategy to 3 different mutations: S45P mutation of catenin beta 1, chromosome breakpoint of solute carrier family 45 member 2-alpha-methylacyl-CoA racemase gene fusion, and V235G mutation of SAFB-like transcription modulator. The results showed that the herpes simplex virus type 1-thymidine kinase insertion rate at the S45P mutation site of catenin beta 1 reached 77.8%, while the insertion rates at the breakpoint of solute carrier family 45 member 2 - alpha-methylacyl-CoA racemase gene fusion were 95.1%-98.7%, and the insertion at V235G of SAFB-like transcription modulator was 51.4%. When these targeting reagents were applied to treat mouse spontaneous liver cancer induced by catenin beta 1S45P or solute carrier family 45 member 2-alpha-methylacyl-CoA racemase, the mice experienced reduced tumor burden and increased survival rate. Similar results were also obtained for the xenografted liver cancer model: Significant reduction of tumor volume, reduction of metastasis rate, and improved survival were found in mice treated with the targeting reagent, in comparison with the control-treated groups. CONCLUSIONS: Our studies suggested that mutation targeting may hold promise as a versatile and effective approach to treating liver cancers.


Asunto(s)
Herpesvirus Humano 1 , Neoplasias Hepáticas , Humanos , Animales , Ratones , Timidina Quinasa/genética , Sistemas CRISPR-Cas/genética , Herpesvirus Humano 1/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Cateninas , Mutación/genética
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