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1.
Front Public Health ; 10: 952075, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36062107

RESUMEN

Objective: Herein, we purposed to explore the association of sleep duration with chest pain among adults in US. Methods: This research work enrolled 13,274 subjects in the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2018. The association of sleep duration with chest pain among adults in US was evaluated by Multivariable logistic regression. Results: To elucidate the association, we made adjustments for gender, BMI, diabetes, smoking status, drinking status, race, marital status, annual family income, hyperlipoidemia, Hypertension. Chest pain incidence decreased by 5% [OR = 0.95 (0.93, 0.98), p = 0.0004] for an increase in sleep duration by 1 h. A generalized additive model (GAM) was used to reseal a U-shaped relationship of sleep duration with incident chest pain. When duration of sleep was <6.5 h, chest pain incidence negatively correlated to sleep duration [OR = 0.77 (0.72, 0.82) P < 0.0001]. However, when sleep duration was ≥6.5 h, chest pain incidence rose with escalating sleep duration [OR = 1.07 (1.03, 1.11) p = 0.0014]. Conclusions: Duration of sleep was established to be independently linked with an increase in the occurrence of chest pain. Excessive sleep, as much as insufficient sleep, increases the risk of chest pain. Both excessive sleep and insufficient sleep are associated with an increased risk of chest pain.


Asunto(s)
Privación de Sueño , Sueño , Adulto , Dolor en el Pecho/epidemiología , Estudios Transversales , Humanos , Encuestas Nutricionales
2.
Breast Cancer (Auckl) ; 15: 11782234211015753, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34103922

RESUMEN

PURPOSE: Clinical studies have shown that breast cancer risk is increased in hypertensive women. The underlying molecular mechanism remains undetermined. The current study tests our hypothesis that G protein coupled receptor kinase 4 (GRK4) is a molecule that links hypertension and breast cancer. GRK4 plays an important role in regulation of renal sodium excretion. Sustained activation of GRK4 as in the circumstances of single nucleotide polymorphism (SNPs) causes hypertension. Expression of GRK4 in the kidney is regulated by cMyc, an oncogene that is amplified in breast cancer. METHODS: Western analysis was used to evaluate GRK4 protein expression in seven breast cancer cell lines. GRK4 gene single nucleotide polymorphism in breast cancer cell lines and in breast cancer cDNA arrays were determined using TaqMan Genotyping qPRC. The function of GRK4 was evaluated in MCF-7 cells with cMyc knock-down and GRK4 re-expression and in MDA-MB-468 cells expressing inducible GRK4 shRNA lentivirus constructs. Nuclei counting and 5-Bromo-2'-deoxy-uridine (BrdU) labeling were used to evaluate cell growth and proliferation. RESULTS: Genotyping of GRK4 SNPs in breast cancer cDNA arrays (n = 94) revealed that the frequency of carrying two hypertension related SNPs A142 V or R65 L is threefold higher in breast cancer patients than in healthy people (P = 7.53E-11). GRK4 protein is expressed in seven breast cancer cell lines but not the benign mammary epithelial cell line, MCF-10A. Three hypertension related SNPs in the GRK4 gene were identified in the breast cancer cell lines. Except for BT20, all other breast cancer lines have 1-3 GRK4 SNPs of which A142 V occurs in all 6 lines. MDA-MB-468 cells contain homozygous A142 V and R65 L SNPs. Knocking down cMyc in MCF-7 cells significantly reduced the growth rate, which was rescued by re-expression of GRK4. We then generated three stable GRK4 knock-down MDA-MB-468 lines using inducible lentiviral shRNA vectors. Doxycycline (Dox) induced GRK4 silencing significantly reduced GRK4 mRNA and protein levels, growth rates, and proliferation. As a marker of cell proliferation, the percentage of BrdU-labeled cells decreased from 45 ± 3% in the cells without Dox to 32 ± 5% in the cells treated with 0.1 µg/mL Dox. CONCLUSIONS: GRK4 acts as an independent proliferation promotor in breast cancer. Our results suggest that targeted inhibition of GRK4 could be a new therapy for both hypertension and breast cancer.

3.
Ying Yong Sheng Tai Xue Bao ; 31(2): 625-633, 2020 Feb.
Artículo en Chino | MEDLINE | ID: mdl-32476357

RESUMEN

We isolated bacteria from the phycosphere of Scenedesmus obliques and sequenced 16S rDNAs to establish algae-bacterial co-culture systems. Further, we examined effects of the bacteria on algal growth, and parameters associated with physio-biochemical and oil-producing characteristics of S. obliquus. Seven bacterial strains were isolated, including Micrococcus (strains 1-1, 1-2 and 1-3), Pseudomonas sp. (strains 2-1 and 2-2), Exiguobacterium (strain-3) and Staphylococcus sp. (strain-4). Among them, two bacteria (strain 1-2 and strain 2-1) were characterized as the dominant growth-promoting bacterial strains, which significantly increased algal growth, pigment production, and oil enrichment. After eight days cultivation under microalgal-bacterial (strain 1-2) symbiotic systemat at an initial ratio of 1:10, biomass of S. obliquus was 4.27 g·L-1, about 46.0% higher than that of the control. The contents of chlorophyll a, chlorophyll b and carotenoids were increased by 12.1%, 16.7% and 25.0%, respectively. Oil content was increased by 14.0% and reached to 25.7%, and the oleic acid content was significantly higher than that of the control and up to 16.4%. When co-cultured with Pseudomonas sp. (strain 2-1) for eight days at an initial ratio of 1:5, algal biomass, chlorophyll a, chlorophyll b and carotenoids contents were higher than that of the control by 47.9%, 16.0%, 17.5% and 19.9%, respectively. The total oil (27.1%) and oleic acid (18.2%) contents were increased by 20.4% and 64.0%, respectively. We concluded that Micrococcus (strain 1-2) and Pseudomonas sp. (strain 2-1) could significantly promote algal growth and increase oil production by their beneficial interaction with S. obliques, which could be potentially used in commercial production of S. obliques.


Asunto(s)
Microalgas , Scenedesmus , Bacterias , Biomasa , Clorofila A
4.
Langmuir ; 36(22): 6228-6237, 2020 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-32388986

RESUMEN

The impact of thermal history on the kinetic response of thin thermoresponsive diblock copolymer poly(diethylene glycol monomethyl ether methacrylate)-block-poly(poly(ethylene glycol) methyl ether methacrylate), abbreviated as PMEO2MA-b-POEGMA300, films is investigated by in situ neutron reflectivity. The PMEO2MA and POEGMA300 blocks are both thermoresponsive polymers with a lower critical solution temperature. Their transition temperatures (TTs) are around 25 °C (TT1, PMEO2MA) and 60 °C (TT2, POEGMA300). Thus, by applying different temperature protocols (20 to 60 or 20 to 40 to 60 °C), the PMEO2MA-b-POEGMA300 thin films experience different thermal histories: the first protocol directly switches from a swollen to a collapsed state, whereas the second one switches first from a swollen to a semicollapsed and finally to a collapsed state. Although the applied thermal histories differ, the response and final state of the collapsed films are very close to each other. After the thermal stimulus, both films present a complicated response composed of an initial shrinkage, followed by a rearrangement. Interestingly, a subsequent reswelling of the collapsed film is only observed in the case of having applied a thermal stimulus of 20 to 40 °C. The normalized film thickness and the D2O amount of each layer in the PMEO2MA-b-POEGMA300 films are consistent at the end of the two different thermal stimuli. Hence, it can be concluded that the thermal history does not influence the final state of the PMEO2MA-b-POEGMA300 films upon heating. Based on this property, these thin films are especially suitable for the temperature switches on the nanoscale, which may experience different thermal histories.

5.
Kaohsiung J Med Sci ; 35(11): 659-671, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31332950

RESUMEN

Prostate cancer (PCa) remains the secondary highest cause of cancer-related death in the United States in men. It has been reported that microRNAs can serve as key regulators in tumor development and progression in various cancers including PCa. In this study, we examined the effect of miR-498 on proliferation, radiosensitivity, invasion, and migration of PCa cells. The proliferation of LNCaP and DU-145 PCa cells with altered expression of miR-498 was evaluated by MTT assay. The invasion and migration of LNCaP and DU-145 PCa cells were assess by matrigel invasion assay and transwell migration assay. The protein expression level in PCa cells was examined by western blot. The function of miR-498 on radiation-induced apoptosis in LNCaP and DU-145 PCa cells was detected by Caspase-Glo3/7 assay. Forced expression of miR-498 improved the proliferation, invasion and migration in PCa cells. Furthermore, miR-498 decreased the sensitivity of PCa cells after ionizing radiation treatment. MiR-498 reduced the radiation-induced apoptosis in PCa cells by regulation of BAX and Bcl-2 expression. Meanwhile, miR-498 altered the expression of E-cadherin, N-cadherin, snail, and Vimentin in both LNCaP and DU-145 PCa cells and regulated epithelial to mesenchymal transition (EMT). Further study showed that aberrant expression of miR-498 changed the expression levels of phosphatase and tensin homolog and p-AKT in LNCaP and DU-145 PCa cells. In a summary, miR-498 displayed important roles in tumor development and progression in PCa cells, and might act as a potential prognostic biomarker and predict radiotherapy response in PCa.


Asunto(s)
Movimiento Celular/genética , MicroARNs/metabolismo , Fosfohidrolasa PTEN/metabolismo , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Tolerancia a Radiación/genética , Regiones no Traducidas 3'/genética , Apoptosis/genética , Secuencia de Bases , Biomarcadores de Tumor/metabolismo , Línea Celular Tumoral , Proliferación Celular/genética , Supervivencia Celular/genética , Regulación hacia Abajo/genética , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , MicroARNs/genética , Invasividad Neoplásica , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Regulación hacia Arriba/genética
6.
Breast Cancer (Auckl) ; 13: 1178223419844198, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31205415

RESUMEN

PURPOSE: Postmenopausal women with estrogen receptor-positive breast cancers often respond initially to tamoxifen or aromatase inhibitor therapy. Resistance to these treatments usually develops within 12 to 18 months. Clinical studies have demonstrated that high-dose estrogen can induce regression of these endocrine-resistant tumors. However, side-effects of high-dose estradiol (E2) or diethylstilbestrol (DES) limit their usage. Estetrol (E4) is the most abundant estrogen during pregnancy and has a long half-life and a low potential for side-effects. Estetrol might then provide benefits similar to DES on tumor regression but with lesser toxicity. METHODS: In this study, we systematically evaluated the effects of E4 on cell proliferation and apoptosis in wild-type MCF-7 and long-term estrogen-deprived (LTED) MCF-7 cells and compared its effects with E2 and estriol (E3). RESULTS: Estetrol induced apoptosis in LTED cells but stimulated growth of MCF-7 cells at concentrations from 10-11 to 10-8 M. These effects of E4 are similar to those of E2 but require much higher doses. Differing from E2, E4 at 10-12 M induced apoptosis in MCF-7 cells and another pregnancy estrogen, E3, acted similarly. No antagonistic effect of E4 or E3 against E2 occurred when they were combined. CONCLUSIONS: The pro-apoptotic effects of E4 and E3 on LTED cells and at low doses on MCF-7 cells indicate that these steroids could be used as therapeutic agents for endocrine-resistant or sensitive breast cancer.

7.
Oncol Lett ; 15(6): 8417-8423, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29805577

RESUMEN

The present study aimed to analyze the modification of gene expression in bladder cancer (BC) by identifying significant differentially expressed genes (DEGs) and functionally assess them using bioinformatics analysis. To achieve this, two microarray datasets, GSE24152 (which included 10 fresh tumor tissue samples from urothelial bladder carcinoma patients and 7 benign mucosa samples from the bladder), and GSE42089 (which included 10 tissues samples from urothelial cell carcinoma patients and 8 tissues samples from the normal bladder), were downloaded from the Gene Expression Omnibus database for further analysis. Differentially expressed genes (DEGs) were screened between benign the mucosa and control groups in GSE24152 and GSE42089 datasets. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analysis were performed on overlapping DEGs identified in GSE24152 and GSE42089. Protein-protein interaction (PPI) networks and sub-networks were then constructed to identify key genes and main pathways. GO terms analysis was also performed for the selected clusters. In total, 1,325 DEGs in GSE24152 and 647 DEGs in GSE42089 were screened, in which 619 common DEGs were identified. The DEGs were mainly enriched in pathways and GO terms associated with mitotic and chromosome assembly, including nucleosome assembly, spindle checkpoint and DNA replication. In the interaction network, progesterone receptor (PGR), MAF bZIP transcription factor G (MAFG), cell division cycle 6 (CDC6) and members of the minichromosome maintenance family (MCMs) were identified as key genes. Histones were also considered to be significant factors in BC. Nucleosome assembly and sequence-specific DNA binding were the most significant clustered GO terms. In conclusion, the DEGs, including PGR, MAFG, CDC6 and MCMs, and those encoding the core histone family were closely associated with the development of BC via pathways associated with mitotic and chromosome assembly.

8.
Mol Pharm ; 14(1): 1-13, 2017 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-26992462

RESUMEN

The RAS and mTOR inhibitor S-trans-trans-farnesylthiosalicylic acid (FTS) is a promising anticancer agent with moderate potency, currently undergoing clinical trials as a chemotherapeutic agent. FTS has displayed its potential against a variety of cancers including endocrine resistant breast cancer. However, the poor pharmacokinetics profile attributed to its high hydrophobicity is a major hindrance for its continued advancement in clinic. One of the ways to improve its therapeutic potential would be to enhance its bioavailability to cancer tissue by developing a method for targeted delivery. In the current study, FTS was conjugated with the cancer-targeting heptamethine cyanine dye 5 to form the FTS-dye conjugate 11. The efficiency of tumor targeting properties of conjugate 11 against cancer cell growth and mTOR inhibition was evaluated in vitro in comparison with parent FTS. Cancer targeting of 11 in a live mouse model of MCF7 xenografts was demonstrated with noninvasive, near-infrared fluorescence (NIRF) imaging. The results from our studies clearly suggest that the bioavailability of FTS is indeed improved as indicated by log P values and cancer cell uptake. The FTS-dye conjugate 11 displayed higher potency (IC50 = 16.8 ± 0.5 µM) than parent FTS (IC50 = ∼51.3 ± 1.8 µM) and inhibited mTOR activity in the cancer cells at a lower concentration (12.5 µM). The conjugate 11 was shown to be specifically accumulated in tumors as observed by in vivo NIRF imaging, organ distribution, and ex vivo tumor histology along with cellular level confocal microscopy. In conclusion, the conjugation of FTS with cancer-targeting heptamethine cyanine dye improved its pharmacological profile.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Carbocianinas/administración & dosificación , Farnesol/análogos & derivados , Salicilatos/farmacología , Animales , Disponibilidad Biológica , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Farnesol/farmacología , Femenino , Humanos , Células MCF-7 , Ratones , Ratones Desnudos , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Distribución Tisular , Proteínas ras/metabolismo
9.
J Steroid Biochem Mol Biol ; 170: 61-64, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-27174719

RESUMEN

The first tissue-selective estrogen complex (TSEC), consisting of a combination of a conjugated equine estrogen (CEE) and bazedoxifene (BZA), has been approved for treatment of the menopause in the USA and European Union. We have postulated that this TSEC might block the estrogenic effects of CEE on breast tissue and thereby prevent breast cancer growth. This manuscript, representing a presentation at a Festschrift honoring Evan Simpson, reviews our published data BZA blocked the in vitro effects of both estradiol and CEE on cell growth and gene expression in MCF-7 cells. BZA completely blocked CEE- or E2-stimulated ductal and terminal end bud growth of immature murine mammary glands and the growth of experimental breast cancers. These findings provide a rationale for future clinical studies to determine whether this TSEC prevents the growth of occult breast cancer in women.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Estrógenos Conjugados (USP)/farmacología , Indoles/farmacología , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Animales , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Estrógenos/metabolismo , Femenino , Humanos
10.
Int J Clin Exp Pathol ; 8(6): 6397-406, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26261515

RESUMEN

Multidrug resistance (MDR) is the main obstacle to successful chemotherapy for patients with gastric cancer. The microRNA miR-218 influences various pathobiological processes in gastric cancer, and its down-regulation in this disease raises the question of whether it normally inhibits MDR. In this study we observed that two MDR gastric cancer cell lines showed lower expression of miR-218 compared with their chemosensitive parental cell line. Overexpressing miR-218 chemosensitizes gastric cancer cells, slowed efflux of adriamycin, and accelerated drug-induced apoptosis. We identified the smoothened (SMO) gene as a functional target of miR-218, and found that SMO overexpression counteracts the chemosensitizing effects of miR-218. These findings suggest that miR-218 inhibits MDR of gastric cancer cells by down-regulating SMO expression.


Asunto(s)
Resistencia a Múltiples Medicamentos/genética , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica/genética , MicroARNs/genética , Receptores Acoplados a Proteínas G/biosíntesis , Neoplasias Gástricas/genética , Western Blotting , Línea Celular Tumoral , Citometría de Flujo , Proteínas Hedgehog/biosíntesis , Proteínas Hedgehog/genética , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Acoplados a Proteínas G/genética , Receptor Smoothened , Transfección
11.
Apoptosis ; 20(6): 821-30, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25721362

RESUMEN

Estrogens stimulate growth of hormone-dependent breast cancer but paradoxically induce tumor regress under certain circumstances. We have shown that long-term estrogen deprivation (LTED) enhances the sensitivity of hormone dependent breast cancer cells to estradiol (E2) so that physiological concentrations of estradiol induce apoptosis in these cells. E2-induced apoptosis involve both intrinsic and extrinsic pathways but precise mechanisms remain unclear. We found that exposure of LTED MCF-7 cells to E2 activated AMP activated protein kinase (AMPK). In contrast, E2 inhibited AMPK activation in wild type MCF-7 cells where E2 prevents apoptosis. As a result of AMPK activation, the transcriptional activity of FoxO3, a downstream factor of AMPK, was up-regulated in E2 treatment of LTED. Increased activity of FoxO3 was demonstrated by up-regulation of three FoxO3 target genes, Bim, Fas ligand (FasL), and Gadd45α. Among them, Bim and FasL mediate intrinsic and extrinsic apoptosis respectively and Gadd45α causes cell cycle arrest at the G2/M phase. To further confirm the role of AMPK in apoptosis, we used AMPK activator AICAR in wild type MCF-7 cells and examined apoptosis, proliferation and expression of Bim, FasL, and Gadd45α. The effects of AICAR on these parameters recapitulated those observed in E2-treated LTED cells. Activation of AMPK by AICAR also increased expression of Bax in MCF-7 cells and its localization to mitochondria, which is a required process for apoptosis. These results reveal that AMPK is an important factor mediating E2-induced apoptosis in LTED cells, which is implicative of therapeutic potential for relapsing breast cancer after hormone therapy.


Asunto(s)
Apoptosis/efectos de los fármacos , Neoplasias de la Mama/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Estradiol/farmacología , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacología , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteína 11 Similar a Bcl2 , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Estrógenos/metabolismo , Proteína Ligando Fas/metabolismo , Femenino , Proteína Forkhead Box O3 , Factores de Transcripción Forkhead/metabolismo , Humanos , Hipoglucemiantes/farmacología , Proteínas de la Membrana/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Ribonucleótidos/farmacología
12.
Steroids ; 99(Pt A): 61-6, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25168343

RESUMEN

Epidemiologic studies link several factors related to estrogen production in women to an increased risk of breast cancer. These include early menarche, late menopause, obesity, use of post-menopausal hormone therapy, and plasma estradiol levels. Two possible mechanisms have been proposed to explain the increased risk: (1) estrogen receptor (ER) mediated stimulation of breast cell proliferation with a concomitant enhanced rate of mutations and (2) metabolism of estradiol to genotoxic metabolites with a resulting increase in DNA mutations. The metabolism of estradiol can cause DNA damage in two ways: (a) formation of estradiol-adenine - guanine adducts which are released from the DNA backbone leaving depurinated sites which undergo error prone DNA repair and mutations and (b) generation of oxygen free radicals resulting from redox cycling of 4-OH estradiol to the 3-4 estradiol quinone and back conversion to 4-OH estradiol. If one or both pathways are operative, sufficient numbers of mutations accumulate over a long period of time to induce neoplastic transformation. Our studies are based on the hypothesis that both receptor-mediated and genotoxic pathways contribute to breast cancer. We initially demonstrated that MCF-7 breast cancer cells and normal breast tissue in aromatase transfected mice contain the enzymes necessary to convert estradiol to the estradiol DNA adducts. We then utilized a highly reductionist model to separately analyze the effect of estrogen receptor alpha (ER) on tumor formation and the effects of estrogen depletion by castration in ER knock out/Wnt-1 (ERKO/Wnt) transgenic animals to assess the effects of estradiol in the absence of an ER. Estradiol was added back in castrate ERKO/Wnt animals to determine if Koch's postulates could be fulfilled to increase the incidence of cancer with administration of exogenous estradiol. Finally, we assessed the effects of an aromatase inhibitor on tumor incidence in non-castrate, ERKO/Wnt animals. The studies demonstrated the conversion of estradiol to genotoxic metabolites in breast tissue. In addition, knockout of ERα caused a reduction in incidence of tumor formation and a delay in the occurrence of those that formed. Oophorectomy further reduced the incidence of tumors and delayed their onset whereas estradiol add-back returned the incidence rate to that observed before oophorectomy. The aromatase inhibitor, letrozole, delayed the onset of tumor formation. Taken together, these data support a role for estradiol metabolism as one of the components in the development of experimental breast cancer.


Asunto(s)
Neoplasias de la Mama/etiología , Receptor alfa de Estrógeno/metabolismo , Estrógenos/metabolismo , Animales , Aromatasa/genética , Aromatasa/metabolismo , Inhibidores de la Aromatasa/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/mortalidad , Supervivencia sin Enfermedad , Receptor alfa de Estrógeno/genética , Estrógenos/toxicidad , Femenino , Humanos , Células MCF-7/metabolismo , Glándulas Mamarias Animales/metabolismo , Ratones Noqueados , Ratones Transgénicos , Receptores de Estrógenos/metabolismo , Proteína Wnt1/genética , Proteína Wnt1/metabolismo
13.
PLoS Genet ; 10(9): e1004566, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25188243

RESUMEN

Overexpression of the histone methyltransferase MMSET in t(4;14)+ multiple myeloma patients is believed to be the driving factor in the pathogenesis of this subtype of myeloma. MMSET catalyzes dimethylation of lysine 36 on histone H3 (H3K36me2), and its overexpression causes a global increase in H3K36me2, redistributing this mark in a broad, elevated level across the genome. Here, we demonstrate that an increased level of MMSET also induces a global reduction of lysine 27 trimethylation on histone H3 (H3K27me3). Despite the net decrease in H3K27 methylation, specific genomic loci exhibit enhanced recruitment of the EZH2 histone methyltransferase and become hypermethylated on this residue. These effects likely contribute to the myeloma phenotype since MMSET-overexpressing cells displayed increased sensitivity to EZH2 inhibition. Furthermore, we demonstrate that such MMSET-mediated epigenetic changes require a number of functional domains within the protein, including PHD domains that mediate MMSET recruitment to chromatin. In vivo, targeting of MMSET by an inducible shRNA reversed histone methylation changes and led to regression of established tumors in athymic mice. Together, our work elucidates previously unrecognized interplay between MMSET and EZH2 in myeloma oncogenesis and identifies domains to be considered when designing inhibitors of MMSET function.


Asunto(s)
Metilación de ADN/genética , Epigénesis Genética/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Histonas/metabolismo , Mieloma Múltiple/genética , Complejo Represivo Polycomb 2/metabolismo , Unión Proteica/genética , Animales , Línea Celular , Transformación Celular Neoplásica/genética , Cromatina/genética , Femenino , Células HEK293 , N-Metiltransferasa de Histona-Lisina/genética , Histonas/genética , Humanos , Lisina/genética , Ratones , Ratones Endogámicos C57BL , Mieloma Múltiple/metabolismo , Complejo Represivo Polycomb 2/genética , ARN Interferente Pequeño/genética
14.
World J Gastroenterol ; 20(32): 11347-55, 2014 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-25170221

RESUMEN

AIM: To investigate the molecular mechanisms of miRNA in advanced gastric cancers (AGCs) before and after cytoreductive surgery (CRS) + hyperthermic intraperitoneal chemotherapy (HIPEC). METHODS: A miRNA microarray containing human mature and precursor miRNA sequences was used to compare expression profiles in serum samples of 5 patients with AGC before and after CRS + HIPEC. The upregulation of miR-218 was confirmed by real-time reverse transcription polymerase chain reaction and its expression was analyzed in SGC7901 gastric cancer cells. RESULTS: miRNA microarray chip analysis found that the level of miR-218 expression was upregulated more than 8 fold after CRS + HIPEC. Furthermore, miR-218 increased gastric cancer cell chemosensitivity to cisplatin in vitro and inhibited gastric cell tumor growth in nude mice in vivo (0.5 vs 0.78, P < 0.05). CONCLUSION: Our results indicated that targeting miR-218 may provide a strategy for blocking the development of gastric cancer and reverse the multi-drug resistance of gastric cell lines.


Asunto(s)
Antineoplásicos/administración & dosificación , Biomarcadores de Tumor/genética , Cisplatino/administración & dosificación , Procedimientos Quirúrgicos de Citorreducción , Gastrectomía/métodos , Hipertermia Inducida , MicroARNs/genética , Neoplasias Gástricas/terapia , Anciano , Animales , Biomarcadores de Tumor/sangre , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Quimioterapia Adyuvante , Relación Dosis-Respuesta a Droga , Femenino , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica , Humanos , Concentración 50 Inhibidora , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , MicroARNs/sangre , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Perfusión , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Gástricas/sangre , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Factores de Tiempo , Transfección , Resultado del Tratamiento , Carga Tumoral/efectos de los fármacos , Regulación hacia Arriba , Ensayos Antitumor por Modelo de Xenoinjerto
15.
BMC Syst Biol ; 8: 1338, 2014 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-25551281

RESUMEN

BACKGROUND: Over the past years, tremendous efforts have been made to elucidate the molecular basis of the initiation and progression of ovarian cancer. However, most existing studies have been focused on individual genes or a single type of data, which may lack the power to detect the complex mechanisms of cancer formation by overlooking the interactions of different genetic and epigenetic factors. RESULTS: We propose an integrative framework to identify genetic and epigenetic features related to ovarian cancer and to quantify the causal relationships among these features using a probabilistic graphical model based on the Cancer Genome Atlas (TCGA) data. In the feature selection, we first defined a set of seed genes by including 48 candidate tumor suppressors or oncogenes and an additional 20 ovarian cancer related genes reported in the literature. The seed genes were then fed into a stepwise correlation-based selector to identify 271 additional features including 177 genes, 82 copy number variation sites, 11 methylation sites and 1 somatic mutation (at gene TP53). We built a Bayesian network model with a logit link function to quantify the causal relationships among these features and discovered a set of 13 hub genes including ARID1A, C19orf53, CSKN2A1 and COL5A2. The directed graph revealed many potential genetic pathways, some of which confirmed the existing results in the literature. Clustering analysis further suggested four gene clusters, three of which correspond to well-defined cellular processes including cell division, tumor invasion and mitochondrial system. In addition, two genes related to glycoprotein synthesis, PSG11 and GALNT10, were found highly predictive for the overall survival time of ovarian cancer patients. CONCLUSIONS: The proposed framework is effective in identifying possible important genetic and epigenetic features that are related to complex cancer diseases. The constructed Bayesian network has identified some new genetic/epigenetic pathways, which may shed new light into the molecular mechanisms of ovarian cancer.


Asunto(s)
Redes Neurales de la Computación , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/genética , Anciano , Análisis por Conglomerados , Simulación por Computador , Variaciones en el Número de Copia de ADN , Metilación de ADN , Epigenómica , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Persona de Mediana Edad , Familia de Multigenes , Mutación , Regiones Promotoras Genéticas/genética , Análisis de Supervivencia
16.
Zhonghua Yi Xue Za Zhi ; 93(14): 1063-6, 2013 Apr 09.
Artículo en Chino | MEDLINE | ID: mdl-23902837

RESUMEN

OBJECTIVE: To explore the functions of connective tissue growth factor (CTGF) in the restoration of hair follicles with a mixture of human dermal papilla cells and human hair follicle outer root sheath cells in vitro in nude mice. METHODS: Human hair follicle outer root sheath cells (hfORS) and human hair dermal papilla cells (hDP) were cultured in vitro and mixed in a fixed ratio (hfORS: hDP = 5:1). Flow cytometry was used to detect the content of CD200(+) cells in human hair follicle outer root sheath cells.And 8 nude mice were divided randomly into 2 groups according to a random number table and back wounds produced. Group A was transplanted with cell mixture plus 20 µg/L CTGF. Group B was transplanted with cell mixture alone. After 8 weeks of transplantation, the development of hair follicle formation was observed histologically.PCR was used to detect the expression of human specific DNA and mice DNA in transplants. RESULTS: The portion of CD200(+) cells in cultured hfORS was 19.65%. At 8 weeks after implantation, hair follicle formation could be observed in Group A (268 ± 96) more than Group B (62 ± 20). The difference was statistically significant (P < 0.05). And PCR showed that there was human composition in transplant. CONCLUSION: CTGF can induce the formation of hair follicle by promoting the interference between hDP and hfORS.


Asunto(s)
Factor de Crecimiento del Tejido Conjuntivo/farmacología , Folículo Piloso/citología , Ingeniería de Tejidos/métodos , Animales , Trasplante de Células , Células Cultivadas , Humanos , Masculino , Ratones , Ratones Desnudos , Células Madre/citología
17.
J Steroid Biochem Mol Biol ; 137: 150-6, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23748149

RESUMEN

An estimated 7% of 40-80 year old women dying of unrelated causes harbor occult breast tumors at autopsy. These lesions are too small to be detected by mammography, a method which requires tumors to be approximately 1cm in diameter to be diagnosed. Tumor growth rates, as assessed by "effective doubling times" on serial mammography range from 10 to >700 days with a median of approximately 200 days. We previously reported two models, based on iterative analysis of these parameters, to describe the biologic behavior of undiagnosed, occult breast tumors. One of our models is biologically based and includes parameters of a 200 day effective doubling time, 7% prevalence of occult tumors in the 40-80 aged female population and a detection threshold of 1.16 cm and the other involves computer based projections based on age related breast cancer incidence. Our models facilitate interpretation of the Women's Health Initiative (WHI) and anti-estrogen prevention studies. The biologically based model suggests that menopausal hormone therapy with conjugated equine estrogens plus medroxyprogesterone acetate (MPA) in the WHI trial primarily promoted the growth of pre-existing, occult lesions and minimally initiated de novo tumors. The paradoxical reduction of breast cancer incidence in women receiving estrogen alone is consistent with a model that this hormone causes apoptosis in women deprived of estrogen long term as a result of the cessation of estrogen production after the menopause. Understanding of the kinetics of occult tumors suggests that breast cancer "prevention" with anti-estrogens or aromatase inhibitors represents early treatment rather than a reduction in de novo tumor formation. Our in vivo data suggest that the combination of a SERM, bazedoxifene (BZA), with conjugated equine estrogen (CEE) acts to block maturation of the mammary gland in oophorectomized, immature mice. This hormonal combination is defined by the generic term, tissue selective estrogen complex or TSEC. Xenograft studies with the BZA/CEE combination show that it blocks the growth of occult, hormone dependent tumors in nude mice. These pre-clinical data suggest that the BZA/CEE TSEC combination may prevent the growth of occult breast tumors in women. Based on the beneficial effects of this TSEC combination on symptoms and fracture prevention in menopausal women, the combination of BZA/CEE might be used as a means both to treat menopausal symptoms and to prevent breast cancer. This article is part of a Special Issue entitled 'CSR 2013'.


Asunto(s)
Neoplasias de la Mama/epidemiología , Terapia de Reemplazo de Estrógeno/efectos adversos , Neoplasias Primarias Desconocidas/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Persona de Mediana Edad
18.
Biostatistics ; 14(3): 600-11, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23428932

RESUMEN

Copy number variations (CNVs) are a significant source of genetic variation and have been found frequently associated with diseases such as cancers and autism. High-throughput sequencing data are increasingly being used to detect and quantify CNVs; however, the distributional properties of the data are not fully understood. A hidden Markov model (HMM) is proposed using inhomogeneous emission distributions based on negative binomial regression to account for the sequencing biases. The model is tested on the whole genome sequencing data and simulated data sets. An algorithm for CNV detection is implemented in the R package CNVfinder. The model based on negative binomial regression is shown to provide a good fit to the data and provides competitive performance compared with methods based on normalization of read counts.


Asunto(s)
Variaciones en el Número de Copia de ADN , Modelos Genéticos , Modelos Estadísticos , Algoritmos , Distribución Binomial , Bioestadística , Simulación por Computador , Bases de Datos de Ácidos Nucleicos/estadística & datos numéricos , Secuenciación de Nucleótidos de Alto Rendimiento/estadística & datos numéricos , Humanos , Cadenas de Markov , Programas Informáticos
19.
Nucl Med Biol ; 40(3): 351-60, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23375364

RESUMEN

PURPOSE: Development of a heptamethine cyanine based tumor-targeting PET imaging probe for noninvasive detection and diagnosis of breast cancer. METHODS: Tumor-specific heptamethine-cyanine DOTA conjugate complexed with Cu-64 (PC-1001) was synthesized for breast cancer imaging. In vitro cellular uptake studies were performed in the breast cancer MCF-7 and noncancerous breast epithelial MCF-10A cell lines to establish tumor specificity. In vivo time-dependent fluorescence and PET imaging of breast tumor xenografts in mice were performed. Blood clearance, biodistribution, and tumor-specific uptake and plasma binding of PC-1001 were quantified. Tumor histology (H&E staining) and fluorescence imaging were examined. RESULTS: PC-1001 displayed similar fluorescence properties (ε=82,880cm(-1)M(-1), Ex/Em=750/820nm) to the parental dye. Time-dependent cellular accumulation indicated significantly higher probe uptake (>2-fold, 30min) in MCF-7 than MCF-10A cells and the uptake was observed to be mediated by organic anion transport peptides (OATPs) system. In vivo studies revealed that PC-1001 has desirable accumulation profile in tumor tissues, with tumor versus muscle uptake of about 4.3 fold at 24h and 5.8 fold at 48h post probe injections. Blood half-life of PC-1001 was observed to be 4.3±0.2h. Microscopic fluorescence imaging of harvested tumor indicated that the uptake of PC-1001 was restricted to viable rather than necrotic tumor cells. CONCLUSIONS: A highly efficient tumor-targeting PET/fluorescence imaging probe PC-1001 is synthesized and validated in vitro in MCF-7 breast cancer cells and in vivo in mice breast cancer xenograft model.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Carbocianinas/química , Carbocianinas/síntesis química , Radioisótopos de Cobre , Tomografía de Emisión de Positrones , Animales , Transporte Biológico , Neoplasias de la Mama/patología , Carbocianinas/metabolismo , Carbocianinas/farmacocinética , Transformación Celular Neoplásica , Técnicas de Química Sintética , Femenino , Compuestos Heterocíclicos con 1 Anillo/química , Humanos , Células MCF-7 , Ratones , Espectrometría de Fluorescencia , Carga Tumoral
20.
Nucleic Acids Res ; 41(5): 2857-68, 2013 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23325854

RESUMEN

Nucleosome positioning on the chromatin strand plays a critical role in regulating accessibility of DNA to transcription factors and chromatin modifying enzymes. Hence, detailed information on nucleosome depletion or movement at cis-acting regulatory elements has the potential to identify predicted binding sites for trans-acting factors. Using a novel method based on enrichment of mononucleosomal DNA by bacterial artificial chromosome hybridization, we mapped nucleosome positions by deep sequencing across 250 kb, encompassing the cystic fibrosis transmembrane conductance regulator (CFTR) gene. CFTR shows tight tissue-specific regulation of expression, which is largely determined by cis-regulatory elements that lie outside the gene promoter. Although multiple elements are known, the repertoire of transcription factors that interact with these sites to activate or repress CFTR expression remains incomplete. Here, we show that specific nucleosome depletion corresponds to well-characterized binding sites for known trans-acting factors, including hepatocyte nuclear factor 1, Forkhead box A1 and CCCTC-binding factor. Moreover, the cell-type selective nucleosome positioning is effective in predicting binding sites for novel interacting factors, such as BAF155. Finally, we identify transcription factor binding sites that are overrepresented in regions where nucleosomes are depleted in a cell-specific manner. This approach recognizes the glucocorticoid receptor as a novel trans-acting factor that regulates CFTR expression in vivo.


Asunto(s)
Mapeo Cromosómico , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Silenciador del Gen , Nucleosomas/metabolismo , Receptores de Glucocorticoides/fisiología , Sitios de Unión , Factor de Unión a CCCTC , Células CACO-2 , Inmunoprecipitación de Cromatina , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Dexametasona/farmacología , Sitios Genéticos , Glucocorticoides/farmacología , Factor Nuclear 3-alfa del Hepatocito/metabolismo , Humanos , Nucleosomas/genética , Unión Proteica , Receptores de Glucocorticoides/metabolismo , Proteínas Represoras/metabolismo , Elementos de Respuesta , Análisis de Secuencia de ADN , Factores de Transcripción/metabolismo
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