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1.
Anticancer Res ; 44(4): 1683-1693, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38537959

RESUMEN

BACKGROUND/AIM: Prostate cancer (PCa) is lethal. Our aim in this retrospective cohort study was to use machine learning-based methodology to predict PCa risk in patients with benign prostate hyperplasia (BPH), identify potential risk factors, and optimize predictive performance. PATIENTS AND METHODS: The dataset was extracted from a clinical information database of patients at a single institute from January 2000 to December 2020. Patients newly diagnosed with BPH and prescribed alpha blockers/5-alpha-reductase inhibitors were enrolled. Patients were excluded if they had a previous diagnosis of any cancer or were diagnosed with PCa within 1 month of enrolment. The study endpoint was PCa diagnosis. The study utilized the extreme gradient boosting (XGB), support vector machine (SVM) and K-nearest neighbors (KNN) machine-learning algorithms for analysis. RESULTS: The dataset used in this study included 5,122 medical records of patients with and without PCa, with 19 patient characteristics. The SVM and XGB models performed better than the KNN model in terms of accuracy and area under curve. Local interpretable model-agnostic explanation and Shapley additive explanations analysis showed that body mass index (BMI) and late prostate-specific antigen (PSA) were important features for the SVM model, while PSA velocity, late PSA, and BMI were important features for the XGB model. Use of 5-alpha-reductase inhibitor was associated with a higher incidence of PCa, with similar survival outcomes compared to non-users. CONCLUSION: Machine learning can enhance personalized PCa risk assessments for patients with BPH but more research is necessary to refine these models and address data biases. Clinicians should use them as supplementary tools alongside traditional screening methods.


Asunto(s)
Hiperplasia Prostática , Neoplasias de la Próstata , Masculino , Humanos , Próstata , Antígeno Prostático Específico , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/complicaciones , Estudios Retrospectivos , Hiperplasia , Detección Precoz del Cáncer , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/complicaciones , Algoritmos , Aprendizaje Automático , Oxidorreductasas
2.
Sci Rep ; 12(1): 3814, 2022 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-35264581

RESUMEN

We present a new lossy compression algorithm for statistical floating-point data through a representation learning with binary variables. The algorithm finds a set of basis vectors and their binary coefficients that precisely reconstruct the original data. The optimization for the basis vectors is performed classically, while binary coefficients are retrieved through both simulated and quantum annealing for comparison. A bias correction procedure is also presented to estimate and eliminate the error and bias introduced from the inexact reconstruction of the lossy compression for statistical data analyses. The compression algorithm is demonstrated on two different datasets of lattice quantum chromodynamics simulations. The results obtained using simulated annealing show 3-3.5 times better compression performance than the algorithm based on neural-network autoencoder. Calculations using quantum annealing also show promising results, but performance is limited by the integrated control error of the quantum processing unit, which yields large uncertainties in the biases and coupling parameters. Hardware comparison is further studied between the previous generation D-Wave 2000Q and the current D-Wave Advantage system. Our study shows that the Advantage system is more likely to obtain low-energy solutions for the problems than the 2000Q.

3.
Sci Rep ; 11(1): 383, 2021 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-33431895

RESUMEN

Advances in understanding the temperature effect on water dynamics in cellular respiration are important for the modeling of integrated energy processes and metabolic rates. For more than half a century, experimental studies have contributed to the understanding of the catalytic role of water in respiration combustion, yet the detailed water dynamics remains elusive. We combine a super-Arrhenius model that links the temperature-dependent exponential growth rate of a population of plant cells to respiration, and an experiment on isotope labeled 18O2 uptake to H218O transport role and to a rate-limiting step of cellular respiration. We use Phosphofructokinase (PFK-1) as a prototype because this enzyme is known to be a pacemaker (a rate-limiting enzyme) in the glycolysis process of respiration. The characterization shows that PFK-1 water matrix dynamics are crucial for examining how respiration (PFK-1 tetramer complex breathing) rates respond to temperature change through a water and nano-channel network created by the enzyme folding surfaces, at both short and long (evolutionary) timescales. We not only reveal the nano-channel water network of PFK-1 tetramer hydration topography but also clarify how temperature drives the underlying respiration rates by mapping the channels of water diffusion with distinct dynamics in space and time. The results show that the PFK-1 assembly tetramer possesses a sustainable capacity in the regulation of the water network toward metabolic rates. The implications and limitations of the reciprocal-activation-reciprocal-temperature relationship for interpreting PFK-1 tetramer mechanisms are briefly discussed.

4.
Surg Neurol Int ; 12: 631, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35350828

RESUMEN

Background: Intraventricular tumors can generally result in obstructive hydrocephalus as they grow. Rarely, however, some intraventricular tumors develop superficial siderosis (SS) and trigger hydrocephalus, even though the tumor has hardly grown. Here, we present an illustrative case of SS and nonocclusive hydrocephalus caused by subependymoma of the lateral ventricles. Case Description: A 78-year-old man with an intraventricular tumor diagnosed 7 years ago had been suffering from gait disturbance for 2 years. He also developed cognitive impairment. Intraventricular tumors showed little growth on annual magnetic resonance imaging (MRI). MRI T2-star weighted images (T2*WI) captured small intratumoral hemorrhages from the beginning of the follow-up. Three years before, at the same time as the onset of ventricular enlargement, T2*WI revealed low intensity in the whole tumor and cerebral surface. Subsequent follow-up revealed that this hemosiderin deposition had spread to the brain stem and cerebellar surface, and the ventricles had expanded further. Cerebrospinal fluid (CSF) examination revealed xanthochromia. The tumor was completely removed en bloc. Histopathological findings were consistent with those of subependymoma. Although CSF findings improved, SS and hydrocephalus did not improve. Therefore, the patient underwent a lumboperitoneal shunt for CSF diversion after tumor resection. Conclusion: Some intraventricular tumors cause SS and nonobstructive hydrocephalus due to microbleeding, even in the absence of tumor growth. T2*WI and, if necessary, timely CSF examination can allow identification of presymptomatic SS. This follow-up strategy may provide a favorable course by facilitating early intervention in patients with intraventricular lesions, not just subependymomas.

5.
Life Sci ; 257: 118019, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32629002

RESUMEN

Parkinson's disease (PD) is a disease of the human nervous system with an onset, in the sixth and seventh decades of the human life. Chiefly perceived as progressive degeneration of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc) with the ensued loss of dopamine in the striatum and the presence of Lewy bodies, consisting of α-synuclein agglomeration. In which the neuronal bridge between substantia nigra and striatum plays an advent role in the motor system. Dilapidation of these neurons results in dopamine depletion which in-turn makes hay to PD. Eventually, the etiology and pathogenesis of PD were still on a hike of dilemma. Traditional Chinese medicine (TCM), including Chinese herbal remedies, acupuncture, and manipulative therapies, is commonly used as an adjunctive therapy in different diseases, particularly neurological diseases, in Asian countries. Additionally, TCM might improve the prognoses and the quality of life of patients with PD because it induces less adverse drug reactions. The present review describes research on the various neuroprotective components and herbal extracts from herbal medicines in the context of addressing the effects of PD.


Asunto(s)
Medicina Tradicional China/métodos , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/terapia , Animales , Encéfalo/metabolismo , Cuerpo Estriado/metabolismo , Modelos Animales de Enfermedad , Dopamina , Neuronas Dopaminérgicas/efectos de los fármacos , Humanos , Ratones , Ratones Endogámicos C57BL , Fármacos Neuroprotectores/farmacología , Porción Compacta de la Sustancia Negra/metabolismo , Sustancia Negra/efectos de los fármacos , Tirosina 3-Monooxigenasa/metabolismo , alfa-Sinucleína/metabolismo
6.
Stem Cells Dev ; 28(21): 1424-1433, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31495275

RESUMEN

Dome formation can occur in cultured tubular epithelial cells originating from various tissues, including the mammary gland and the kidney. The isolation and characterization of normal kidney epithelial stem cells that give rise to dome-forming tubular cells have never been reported. We attempted to isolate and characterize canine kidney epithelial stem cells using a simple cell culture method that we have previously used to isolate other adult human stem cells. Dome-forming kidney epithelial cells were derived from dissociated adult canine kidney tissues that were cultured in a modified keratinocyte serum-free medium supplemented with N-acetyl-l-cysteine, l-ascorbic acid 2-phosphate, nicotinamide, and fetal bovine serum. These cells exhibited high self-renewal capacity in long-term culture (growth for >13 months and 30 cumulative population doublings) and exhibited characteristics of stem cells, including (1) deficiency in gap junctional intercellular communication, (2) anchorage-independent growth, (3) expression of stem cell markers octamer-binding transcription factor 4 and SRY (sex determining region Y)-box 2, (4) expression of cell surface markers CD24 and CD133, and (5) multipotent differentiation into osteoblasts, adipocytes, chondrocytes, and dome-forming tubular cells. Most of these characteristics are shared by the well-known canine renal tubule-derived immortalized Madin-Darby Canine Kidney cell line. Furthermore, the putative canine kidney stem cells developed in this study formed budding tubule-like organoids on Matrigel and required high cell density (>4,000 cells/cm2) for sustained growth and confluency for dome formation. The signal transducer and activator of transcription-3 (STAT3) phosphorylation inhibitor, AG490, inhibited colony-forming efficiency and dome formation, whereas lipopolysaccharide, an activator of STAT3, increased colony-forming efficiency in a dose-dependent manner. These results are consistent with the hypothesis that high cell density induces STAT3 expression, which promotes both stem cell self-renewal and differentiation into tubular cells. Our novel cell culture method should be useful for the future development of normal human kidney stem cells for clinical applications and for studying mechanisms of nephrotoxicity.


Asunto(s)
Células Epiteliales/citología , Túbulos Renales/citología , Células Madre Multipotentes/citología , Factor de Transcripción STAT3/metabolismo , Antígeno AC133/metabolismo , Animales , Antígeno CD24/metabolismo , Línea Celular , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Perros , Inhibidores Enzimáticos/farmacología , Fallo Renal Crónico/terapia , Lipopolisacáridos , Células de Riñón Canino Madin Darby , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Factores de Transcripción SOXB1/metabolismo , Factor de Transcripción STAT3/antagonistas & inhibidores , Tirfostinos/farmacología
7.
Sci Rep ; 9(1): 10258, 2019 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-31311997

RESUMEN

Numerous scientific and engineering applications require numerically solving systems of equations. Classically solving a general set of polynomial equations requires iterative solvers, while linear equations may be solved either by direct matrix inversion or iteratively with judicious preconditioning. However, the convergence of iterative algorithms is highly variable and depends, in part, on the condition number. We present a direct method for solving general systems of polynomial equations based on quantum annealing, and we validate this method using a system of second-order polynomial equations solved on a commercially available quantum annealer. We then demonstrate applications for linear regression, and discuss in more detail the scaling behavior for general systems of linear equations with respect to problem size, condition number, and search precision. Finally, we define an iterative annealing process and demonstrate its efficacy in solving a linear system to a tolerance of 10-8.

8.
Int J Oncol ; 54(2): 655-664, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30483770

RESUMEN

The overall goal of the present study was to evaluate the chemotherapeutic and cancer­protective properties of D­erythro­sphingosine (sphingosine) and C2­ceramide using a human breast epithelial cell (HBEC) culture system, which represents multiple­stages of breast carcinogenesis. The HBEC model includes Type I HBECs (normal stem), Type II HBECs (normal differentiated) and transformed cells (immortal/non­tumorigenic cells and tumorigenic cells, which are transformed from the same parental normal stem cells). The results of the present study indicate that sphingosine preferentially inhibits proliferation and causes death of normal stem cells (Type I), tumorigenic cells, and MCF7 breast cancer cells, but not normal differentiated cells (Type II). In contrast to the selective anti­proliferative effects of sphingosine, C2­ceramide inhibits proliferation of normal differentiated cells as well as normal stem cells, tumorigenic cells, and MCF7 cancer cells with similar potency. Both sphingosine and C2­ceramide induce apoptosis in tumorigenic cells. Among the sphingosine stereoisomers (D­erythro, D­threo, L­erythro, and L­threo) and sphinganine that were tested, L­erythro­sphingosine most potently inhibits proliferation of tumorigenic cells. The inhibition of breast tumorigenic/cancer cell proliferation by sphingosine was accompanied by inhibition of telomerase activity. Sphingosine at non­cytotoxic concentrations, but not C2­ceramide, induces differentiation of normal stem cells (Type I), thereby reducing the number of stem cells that are more susceptible to neoplastic transformation. To the best of our knowledge, the present study demonstrates one of the first results that sphingosine can be a potential chemotherapeutic and cancer­protective agent, whereas C2­ceramide is not an ideal chemotherapeutic and cancer­protective agent due to its anti­proliferative effects on Type II HBECs and its inability to induce the differentiation of Type I to Type II HBECs.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Mama/efectos de los fármacos , Esfingosina/análogos & derivados , Esfingosina/farmacología , Mama/patología , Neoplasias de la Mama/patología , Carcinogénesis/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Transformación Celular Neoplásica/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Células Epiteliales/patología , Femenino , Humanos , Células MCF-7 , Células Madre Neoplásicas/efectos de los fármacos , Células Madre/efectos de los fármacos
9.
J Cell Physiol ; 234(7): 12042-12050, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30515824

RESUMEN

Adipose-derived mesenchymal stem cells (ADMSCs) are easily accessible and are attractive mesenchymal stem cells for use in regenerative medicine; however their application is frequently restricted due to various challenges present in the environment they are administered. Therefore ADMSCs are preferably preconditioned with various stimulating factors to overcome the barriers developed in any pathological conditions. Here we used ADMSCs from rat adipose based on the abundance of positive markers and preconditioned the cells with extracts from Alpinate Oxyphyllae Fructus (AOF), a traditional Chinese herb used for antiaging, associated various health benefits. The preconditioned stem cells were tested for their potential to drive H9c2 from doxorubicin (Dox)-induced aging. The AOF-treated stem cells enriched stemness in ADMSCs with respect to their stem cells' positive marker, and enhanced their longevity mechanism and elevated the stem cell homing-associated C-X-C chemokine receptor type 7 (CXCR7). The AOF preconditioned stem cells, when cocultured with H9c2 cells, showed effective protection to Dox-induced senescence and stem cell homing to damaged H9c2 cells. The presence of AOF provided greater protective effects in the Dox environment. In addition, AOF-pretreated ADMSCs showed enhanced migration than those treated with AOF in Dox environment. Therefore, our results show that administration of AOF preconditioned stem cells is potentially an effective strategy in the management of aging-associated cardiac disorders.


Asunto(s)
Envejecimiento/efectos de los fármacos , Longevidad/efectos de los fármacos , Células Madre Mesenquimatosas/efectos de los fármacos , Extractos Vegetales/farmacología , Tejido Adiposo/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Doxorrubicina/farmacología , Corazón/efectos de los fármacos , Ratas , Transducción de Señal/efectos de los fármacos
10.
PLoS One ; 13(1): e0191070, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29351316

RESUMEN

BACKGROUND: Peripheral innate immune response may induce sickness behavior through activating microglia, excessive cytokines production, and neuroinflammation. Dexmedetomidine (Dex) has anti-inflammatory effect. We investigated the effects of Dex on lipopolysaccharide (LPS)-induced neuroinflammation and sickness behavior in mice. MATERIALS AND METHODS: BALB/c mice were intraperitoneally (i.p.) injected with Dex (50 ug/kg) or vehicle. One hour later, the mice were injected (i.p.) with Escherichia coli LPS (0.33 mg/kg) or saline (n = 6 in each group). We analyzed the food and water intake, body weight loss, and sucrose preference of the mice for 24h. We also determined microglia activation and cytokines expression in the brains of the mice. In vitro, we determine cytokines expression in LPS-treated BV-2 microglial cells with or without Dex treatment. RESULTS: In the Dex-pretreated mice, LPS-induced sickness behavior (anorexia, weight loss, and social withdrawal) were attenuated and microglial activation was lower than vehicle control. The mRNA expression of TNF-α, MCP-1, indoleamine 2, 3 dioxygenase (IDO), caspase-3, and iNOS were increased in the brain of LPS-challenged mice, which were reduced by Dex but not vehicle. CONCLUSION: Dexmedetomidine diminished LPS-induced neuroinflammation in the mouse brain and modulated the cytokine-associated changes in sickness behavior.


Asunto(s)
Anhedonia/efectos de los fármacos , Encéfalo/efectos de los fármacos , Dexmedetomidina/farmacología , Conducta de Enfermedad/efectos de los fármacos , Inflamación/inducido químicamente , Lipopolisacáridos/toxicidad , Animales , Apoptosis/efectos de los fármacos , Encéfalo/patología , Inflamación/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Microglía/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
11.
Stem Cells Int ; 2016: 4591310, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27807451

RESUMEN

We have previously reported the isolation and culture of a human breast epithelial cell type with stem cell characteristics (Type I HBEC) from reduction mammoplasty using the MSU-1 medium. Subsequently, we have developed several different normal human adult stem cell types from different tissues using the K-NAC medium. In this study, we determined whether this low calcium K-NAC medium with antioxidants (N-acetyl-L-cysteine and L-ascorbic acid-2-phosphate) is a better medium to grow human breast epithelial cells. The results clearly show that the K-NAC medium is a superior medium for prolonged growth (cumulative population doubling levels ranged from 30 to 40) of normal breast epithelial cells that expressed stem cell phenotypes. The characteristics of these mammary stem cells include deficiency in gap junctional intercellular communication, expression of Oct-4, and the ability to differentiate into basal epithelial cells and to form organoid showing mammary ductal and terminal end bud-like structures. Thus, this new method of growing Type I HBECs will be very useful in future studies of mammary development, breast carcinogenesis, chemoprevention, and cancer therapy.

12.
Chem Biol Interact ; 254: 34-44, 2016 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-27216632

RESUMEN

Although, titanium dioxide nanoparticles (TiO2NPs) are nanomaterials commonly used in consumer products, little is known about their hazardous effects, especially on central nervous systems. To examine this issue, ALT astrocyte-like, BV-2 microglia and differentiated N2a neuroblastoma cells were exposed to 6 nm of 100% anatase TiO2NPs. A lipopolysaccharide (LPS) was pre-treated to activate glial cells before NP treatment for mimicking NP exposure under brain injury. We found that ALT and BV-2 cells took up more NPs than N2a cells and caused lower cell viability. TiO2NPs induced IL-1ß in the three cell lines and IL-6 in N2a. LPS-activated BV-2 took up more TiO2NPs than normal BV-2 and released more intra/extracellular reactive oxygen species (ROS), IL-1ß, IL-6 and MCP-1 than did activated BV-2. Involvement of clathrin- and caveolae-dependent endocytosis in ALT and clathrin-dependent endocytosis and phagocytosis in BV-2 both had a slow NP translocation rate to lysosome, which may cause slow ROS production (after 24 h). Although TiO2NPs did not directly cause N2a viability loss, by indirect NP exposure to the bottom chamber of LPS-activated BV-2 in the Transwell system, they caused late apoptosis and loss of cell viability in the upper N2a chamber due to H2O2 and/or TNF-α release from BV-2. However, none of the adverse effects in N2a or BV-2 cells was observed when TiO2NPs were exposed to ALT-N2a or ALT-BV-2 co-culture. These results demonstrate that neuron damage can result from TiO2NP-mediated ROS and/or cytokines release from microglia, but not from astrocytes.


Asunto(s)
Apoptosis/efectos de los fármacos , Comunicación Celular/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Titanio/química , Animales , Astrocitos/citología , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Técnicas de Cocultivo , Endocitosis/efectos de los fármacos , Peróxido de Hidrógeno/metabolismo , Lipopolisacáridos/toxicidad , Lisosomas/metabolismo , Nanopartículas del Metal/química , Ratones , Microglía/citología , Microglía/efectos de los fármacos , Microglía/metabolismo , Neuronas/citología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Óxido Nítrico/metabolismo , Fagocitosis/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
13.
Cancer Res ; 76(15): 4569-78, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27197159

RESUMEN

Rare stochastic mutations may accumulate during dormancy of stem-like cells, but technical limitations in DNA sequencing have limited exploring this possibility. In this study, we employed a recently established deep-sequencing method termed Duplex Sequencing to conduct a genome-wide analysis of mitochondrial (mt) DNA mutations in a human breast stem cell model that recapitulates the sequential stages of breast carcinogenesis. Using this method, we found significant differences in mtDNA among normal stem cells, immortal/preneoplastic cells, and tumorigenic cells. Putative cancer stem-like cell (CSC) populations and mtDNA copy numbers increased as normal stem cells become tumorigenic cells. Transformed cells exhibited lower rare mutation frequencies of whole mtDNA than did normal stem cells. The predicted mtDNA rare mutation pathogenicity was significantly lower in tumorigenic cells than normal stem cells. Major rare mutation types in normal stem cells are C>T/G>A and T>C/A>G transitions, while only C>T/G>A are major types in transformed cells. We detected a total of 1,220 rare point mutations, 678 of which were unreported previously. With only one possible exception (m10342T>C), we did not find specific mutations characterizing mtDNA in human breast CSCs; rather, the mitochondrial genome of CSCs displayed an overall decrease in rare mutations. On the basis of our work, we suggest that this decrease (in particular T>C/A>G transitions), rather than the presence of specific mitochondrial mutations, may constitute an early biomarker for breast cancer detection. Our findings support the hypothesis that the mitochondrial genome is altered greatly as a result of the transformation of normal stem cells to CSCs, and that mtDNA mutation signatures may aid in delineating normal stem cells from CSCs. Cancer Res; 76(15); 4569-78. ©2016 AACR.


Asunto(s)
Neoplasias de la Mama/genética , Mama/patología , Mitocondrias/metabolismo , Carcinogénesis/genética , Femenino , Humanos , Mutagénesis
14.
Reprod Toxicol ; 58: 229-33, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26546977

RESUMEN

Many studies have highlighted the correlation between the increase of bisphenol A (BPA) level in the environment and the incidence of tumor in humans. In human carcinogenesis, the overexpression of cyclooxygenase-2 (COX-2) and epithelial-mesenchymal transition (EMT) are closely related with tumor development. In this study, human endometrial carcinoma cells line (RL95-2) was used to investigate whether BPA can induce EMT and COX-2 expression. The results show that BPA increased growth rate and colony-forming efficiency in a dose-dependent manner, induced EMT and COX-2 gene expression and promoted the migration and invasion ability of RL95-2 cells. Furthermore, our study showed that the expression of COX-2 was essential for BPA-induced cell migration and invasion. The results of this study provide new insights into the mechanism of endometrial cancer cell growth and invasion and potential therapeutic strategy.


Asunto(s)
Compuestos de Bencidrilo/toxicidad , Carcinógenos/toxicidad , Carcinoma/enzimología , Ciclooxigenasa 2/metabolismo , Neoplasias Endometriales/enzimología , Transición Epitelial-Mesenquimal/efectos de los fármacos , Fenoles/toxicidad , Carcinoma/patología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Ciclooxigenasa 2/genética , Relación Dosis-Respuesta a Droga , Neoplasias Endometriales/genética , Neoplasias Endometriales/patología , Femenino , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Invasividad Neoplásica , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , Regulación hacia Arriba
15.
PLoS One ; 10(8): e0136216, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26305705

RESUMEN

Long-lived adult stem cells could accumulate non-repaired DNA damage or mutations that increase the risk of tumor formation. To date, studies on mutations in stem cells have concentrated on clonal (homoplasmic) mutations and have not focused on rarely occurring stochastic mutations that may accumulate during stem cell dormancy. A major challenge in investigating these rare mutations is that conventional next generation sequencing (NGS) methods have high error rates. We have established a new method termed Duplex Sequencing (DS), which detects mutations with unprecedented accuracy. We present a comprehensive analysis of mitochondrial DNA mutations in human breast normal stem cells and non-stem cells using DS. The vast majority of mutations occur at low frequency and are not detectable by NGS. The most prevalent point mutation types are the C>T/G>A and A>G/T>C transitions. The mutations exhibit a strand bias with higher prevalence of G>A, T>C, and A>C mutations on the light strand of the mitochondrial genome. The overall rare mutation frequency is significantly lower in stem cells than in the corresponding non-stem cells. We have identified common and unique non-homoplasmic mutations between non-stem and stem cells that include new mutations which have not been reported previously. Four mutations found within the MT-ND5 gene (m.12684G>A, m.12705C>T, m.13095T>C, m.13105A>G) are present in all groups of stem and non-stem cells. Two mutations (m.8567T>C, m.10547C>G) are found only in non-stem cells. This first genome-wide analysis of mitochondrial DNA mutations may aid in characterizing human breast normal epithelial cells and serve as a reference for cancer stem cell mutation profiles.


Asunto(s)
ADN Mitocondrial/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Glándulas Mamarias Humanas/citología , Mutación , Células Madre/metabolismo , Adulto , Alelos , Análisis Mutacional de ADN/métodos , Femenino , Frecuencia de los Genes , Genoma Mitocondrial , Genotipo , Voluntarios Sanos , Humanos , Sistemas de Lectura Abierta , Adulto Joven
16.
Biotechnol Appl Biochem ; 62(5): 591-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25385323

RESUMEN

Octamer-binding transcription factor 4 (Oct-4), an important gene regulating stem cell pluripotency, is well-known for its ability to reprogram somatic cells in vitro, either alone or in concert with other factors. The aim of this study was to assess the effect of ectopic expression of Oct human amniotic fluid stem cells. We developed a novel method for isolation of putative human amniotic fluid-derived multipotent stem cells. These cells showing mesenchymal stem cell phenotypes (human amniotic fluid-derived mesenchymal stem cells, hAFMSCs) were transfected with a plasmid carrying genes for Oct-4 and the green fluorescent protein (GFP). The stably transfected cells, hAFMSCs-Oct4/GFP, were selected by using G418 and found to express the GFP reporter gene under the control of Oct-4 promoter. We found that hAFMSCs developed by our method possess very high self-renewal ability (about 78 cumulative population doublings) and multilineage differentiation potency. Significantly, the hAFMSCs-Oct4/GFP cells showed enhanced expression of the three major pluripotency genes Oct-4, Nanog, and Sox-2, and increased colony-forming ability and growth rate compared with the parental hAFMSCs. We demonstrated that the ectopic expression of Oct-4 gene in hAFMSCs with high self-renewal ability could upregulate Nanog and Sox-2 gene expression and enhance cell growth rate and colony-forming efficiency. Therefore, the ectopic expression of Oct-4 could be a strategy to develop pluripotency in hAFMSCs for clinical applications.


Asunto(s)
Líquido Amniótico/citología , Expresión Génica Ectópica , Proteínas de Homeodominio/genética , Células Madre Mesenquimatosas/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/genética , Factores de Transcripción SOXB1/genética , Regulación hacia Arriba/genética , Biomarcadores/metabolismo , Diferenciación Celular , Linaje de la Célula , Proliferación Celular , Femenino , Humanos , Células Madre Mesenquimatosas/citología , Proteína Homeótica Nanog , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Embarazo
17.
J Stem Cell Res Ther ; 4(5)2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-27547491

RESUMEN

OBJECTIVE: Excessive alcohol consumption injures the liver resulting in various liver diseases including liver cirrhosis. Advanced liver disease continues to be a major challenge to human health. Liver stem/progenitor cells (LSPCs) are tissue specific precursors with a distinct capacity of multi-lineage differentiation. These precursor cells may play an important role in the process of tissue injury repair and pathological transition of liver structures. At the present time, knowledge about the effect of alcohol on LSPC function during the development of alcoholic liver disease remains absent. This study was conducted to investigate changes in LSPC activity of proliferation and differentiation following alcohol exposure. The disruption of cell signaling mechanisms underlying alcohol-induced alteration of LSPC activities was also examined. METHODS: Primary and immortalized human liver stem cells (HL1-1 cells and HL1-hT1 cells, respectively) were cultured in media optimized for cell proliferation and hepatocyte differentiation in the absence and presence of ethanol. Changes in cell morphology, proliferation and differentiation were determined. Functional disruption of cell signaling components following alcohol exposure was examined. RESULTS: Ethanol exposure suppressed HL1-1 cell growth [as measured by cell 5-bromo-2-deoxyuridine (BrdU) incorporation] mediated by epidermal growth factor (EGF) or EGF plus interleukin-6 (IL-6) in an ethanol dose-dependent manner. Similarly, ethanol inhibited BrdU incorporation into HL1-hT1 cells. Cyclin D1 mRNA expression by HL1-hT1 cells was suppressed when cells were cultured with 50 and 100 mM ethanol. Ethanol exposure induced morphological change of HL1-1 cells toward a myofibroblast-like phenotype. Furthermore, ethanol down-regulated E-cadherin expression while increasing collagen I expression by HL1-1 cells. Ethanol also stimulated Snail transcriptional repressor (Snail) and α-smooth muscle actin (α-SMA) gene expression by HL1-1 cells. CONCLUSION: These results demonstrate that the direct effect of alcohol on LSPCs is inhibiting their proliferation and promoting mesenchymal transition during their differentiation. Alcohol interrupts LSPC differentiation through interfering Snail signaling.

18.
Taiwan J Obstet Gynecol ; 52(2): 246-52, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23915859

RESUMEN

OBJECTIVE: Uterine myoma is the most common benign reproductive tract tumor in women. Despite its high prevalence, the exact pathogenesis of these benign tumors remains unknown. Toward understanding the pathogenic mechanism of these tumors, we attempted to isolate human uterine myoma mesenchymal stem cells (hUM-MSCs), which may be the target cells for tumorigenesis. Furthermore, we tested the response of these hUM-MSCs to the environmental endocrine disruptor, bisphenol A (BPA), which may mimic the action of estrogen in hormone-sensitive organs such as the uterus. MATERIALS AND METHODS: The hUM-MSC lines were clonally derived from uterine myoma tissue using the MSU-1 medium supplemented with N-acetyl-l-cysteine and l-ascorbic acid-2-phosphate. These hUM-MSCs were characterized by reverse transcription polymerase chain reaction (RT-PCR) analysis for the expression of mesenchymal stem cell (MSC) surface markers (e.g., CD90 and CD105) and the transcription factor Oct-4. The proliferation potential was measured by the cumulative population doubling level and the colony-forming efficiency. RESULTS: Putative hUM-MSC lines expressed CD90, CD105, and the stem cell marker gene, Oct-4. The cells were capable of differentiating into adipocytes, osteoblasts, and chondrocytes. Bisphenol A treatment of these hUM-MSCs enhanced cell proliferation and colony-forming efficiency in a dose-responsive manner. At an environmentally relevant concentration (10(-8) M), BPA moreover induced cyclooxygenase-2 (COX-2) gene expression and promoted cell migration and invasiveness. CONCLUSION: The hUM-MSC cell lines can be isolated from uterine myoma tissues. Bisphenol A could enhance cell proliferation and colony-forming efficiency, induce COX-2 gene expression, and promote migration and invasion of hUM-MSCs. The results imply that BPA has a detrimental effect on female health by promoting uterine tumorigenesis.


Asunto(s)
Compuestos de Bencidrilo/farmacología , Ciclooxigenasa 2/genética , Leiomioma/tratamiento farmacológico , Células Madre Mesenquimatosas/efectos de los fármacos , Fenoles/farmacología , Neoplasias Uterinas/tratamiento farmacológico , Diferenciación Celular/efectos de los fármacos , Linaje de la Célula/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Exposición a Riesgos Ambientales , Estrógenos no Esteroides/farmacología , Femenino , Expresión Génica/efectos de los fármacos , Humanos , Leiomioma/patología , Células Madre Mesenquimatosas/patología , Invasividad Neoplásica , Células Tumorales Cultivadas , Neoplasias Uterinas/patología
19.
Nutr Metab (Lond) ; 9(1): 109, 2012 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-23216800

RESUMEN

BACKGROUND: Leptin-deficient ob/ob mice exhibit adipocyte hypertrophy and hyperplasia as well as elevated adipose tissue and systemic inflammation. Multipotent stem cells isolated from adult adipose tissue can differentiate into adipocytes ex vivo and thereby contribute toward increased adipocyte cell numbers, obesity, and inflamm ation. Currently, information is lacking regarding regulation of adipose stem cell numbers as well as leptin-induced inflammation and its signaling pathway in ob/ob mice. METHODS: Using leptin deficient ob/ob mice, we investigated whether leptin injection into ob/ob mice increases adipose stem cell numbers and adipose tissue inflammatory marker MCP-1 mRNA and secretion levels. We also determined leptin mediated signaling pathways in the adipose stem cells. RESULTS: We report here that adipose stem cell number is significantly increased following leptin injection in ob/ob mice and with treatment of isolated stem cells with leptin in vitro. Leptin also up-regulated MCP-1 secretion in a dose- and time-dependent manner. We further showed that increased MCP-1 mRNA levels were due to increased phosphorylation of Signal Transducer and Activator of Transcription 3 (STAT3) Ser727 but not STAT3 Tyr705 phosphorylation, suggesting differential regulation of MCP-1 gene expression under basal and leptin-stimulated conditions in adipose stem cells. CONCLUSIONS: Taken together, these studies demonstrate that leptin increases adipose stem cell number and differentially activates STAT3 protein resulting in up-regulation of MCP-1 gene expression. Further studies of mechanisms mediating adipose stem cell hyperplasia and leptin signaling in obesity are warranted and may help identify novel anti-obesity target strategies.

20.
Toxicol Sci ; 128(2): 365-76, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22552774

RESUMEN

Phthalates are environmental hormone-like molecules that are associated with breast cancer risk and are involved in metastasis, a process that requires the epithelial-mesenchymal transition (EMT). However, few studies have addressed the potential effects of phthalates on stem cells. Here we tested the hypothesis that phthalates such as butyl benzyl phthalate and di-n-butyl phthalate induce EMT in R2d cells, a stem cell-derived human breast epithelial cell line that is responsive to estradiol for tumor development. We observed that phthalates induced EMT as evidenced by morphological changes concomitant with increased expression of mesenchymal markers and decreased expression of epithelial markers. Molecular mechanism studies revealed that histone deacetylase 6 (HDAC6) is required for phthalate-induced cell migration and invasion during EMT in vitro and metastasis into the lungs of nude mice. We also constructed a series of mutant HDAC6 promoter fragments and found that the transcription factor AP-2a plays a novel role in regulating the HDAC6 promoter. Furthermore, phthalates stimulated estrogen receptors and triggered the downstream EGFR-PKA signaling cascade, leading to increased expression of AP-2a in the nucleus. We also observed that phthalates increased expression of the PP1/HDAC6 complex and caused Akt activation and GSK3ß inactivation, leading to transcriptional activation of vimentin through the ß-catenin-TCF-4/LEF1 pathway. Understanding the signaling cascades of phthalates that activate EMT through HDAC6 in breast epithelial stem cells provides the identification of novel therapeutic target for human breast cancer.


Asunto(s)
Transición Epitelial-Mesenquimal/efectos de los fármacos , Histona Desacetilasas/metabolismo , Glándulas Mamarias Humanas/efectos de los fármacos , Ácidos Ftálicos/toxicidad , Células Madre/efectos de los fármacos , Animales , Secuencia de Bases , Cartilla de ADN , Femenino , Citometría de Flujo , Histona Desacetilasa 6 , Histona Desacetilasas/genética , Humanos , Glándulas Mamarias Humanas/citología , Ratones , Ratones Desnudos , Regiones Promotoras Genéticas , Proteína Fosfatasa 1/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Transcripción AP-2/metabolismo , beta Catenina/metabolismo
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