RESUMEN
The ability of human melanoma cells to switch from an epithelial to a mesenchymal phenotype contributes to the metastatic potential of disease. Metalloproteinases (MPs) are crucially involved in this process by promoting the detachment of tumor cells from the primary lesion and their migration to the vasculature. In gray horse melanoma, epithelial-mesenchymal transition (EMT) is poorly understood, prompting us to address MP expression in lesions versus intact skin by transcriptome analyses and the immunofluorescence staining (IF) of gray horse tumor tissue and primary melanoma cells. RNAseq revealed the deregulation of several MPs in gray horse melanoma and, notably, a 125-fold upregulation of matrix metalloproteinase 1 (MMP1) that was further confirmed by RT-qPCR from additional tumor material. The IF staining of melanoma tissue versus intact skin for MMP1 and tumor marker S100 revealed MMP1 expression in all lesions. The co-expression of S100 was observed at different extents, with some tumors scoring S100-negative. The IF staining of primary tumor cells explanted from the tumors for MMP1 showed that the metalloproteinase is uniformly expressed in the cytoplasm of 100% of tumor cells. Overall, the presented data point to MP expression being deregulated in gray horse melanoma, and suggest that MMP1 has an active role in gray horse melanoma by driving EMT-mediated tumor cell dissemination via the degradation of the extracellular matrix. Whilst S100 is considered a reliable tumor marker in human MM, gray horse melanomas do not seem to regularly express this protein.
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Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica , Metaloproteinasa 1 de la Matriz , Melanoma , Animales , Melanoma/patología , Melanoma/enzimología , Melanoma/genética , Melanoma/metabolismo , Caballos , Metaloproteinasa 1 de la Matriz/metabolismo , Metaloproteinasa 1 de la Matriz/genética , Transición Epitelial-Mesenquimal/genética , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/enzimología , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/veterinaria , Neoplasias Cutáneas/metabolismo , Línea Celular Tumoral , Metaloproteasas/metabolismo , Metaloproteasas/genética , HumanosRESUMEN
Anthochlor pigments (chalcones and aurones) play an important role in yellow flower colourization, the formation of UV-honey guides and show numerous health benefits. The B-ring hydroxylation of chalcones is performed by membrane bound cytochrome P450 enzymes. It was assumed that usual flavonoid 3'-hydroxlases (F3'Hs) are responsible for the 3,4- dihydroxy pattern of chalcones, however, we previously showed that a specialized F3'H, namely chalcone 3-hydroxylase (CH3H), is necessary for the hydroxylation of chalcones. In this study, a sequence encoding membrane bound CH3H from Dahlia variabilis was recombinantly expressed in yeast and a purification procedure was developed. The optimized purification procedure led to an overall recovery of 30% recombinant DvCH3H with a purity of more than 84%. The enzyme was biochemically characterized with regard to its kinetic parameters on various substrates, including racemic naringenin, as well as its enantiomers (2S)-, and (2R)-naringenin, apigenin and kaempferol. We report for the first time the characterization of a purified Cytochrome P450 enzyme from the flavonoid biosynthesis pathway, including the transmembrane helix. Further, we show for the first time that recombinant DvCH3H displays a higher affinity for (2R)-naringenin than for (2S)-naringenin, although (2R)-flavanones are not naturally formed by chalcone isomerase.
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Chalcona , Chalconas , Flavanonas , Chalconas/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Flavanonas/química , Flavonoides/metabolismo , Proteínas de Plantas/metabolismo , Especificidad por SustratoRESUMEN
Genetic and biochemical screening approaches often fail to identify functionally relevant pathway networks because many signaling proteins contribute to multiple gene ontology pathways. We developed a DRUGPATH-approach to predict pathway-interactomes from high-content drug screen data. DRUGPATH is based upon combining z-scores of effective inhibitors with their corresponding and validated targets. We test DRUGPATH by comparing homeostatic pathways in human embryonic stem cells (hESCs), human induced pluripotent stem cells (hiPSCs) and human amniotic fluid stem cells (hAFSCs). We show that hAFSCs utilize distinct interactomes compared to hESCs/hiPSCs and that pathways orchestrating cell cycle and apoptosis are strongly interconnected, while pathways regulating survival and size are not. Interestingly, hESCs/hiPSCs regulate their size by growing exact additional sizes during each cell cycle. Chemical and genetic perturbation studies show that this "adder-model" is dependent on the DNA-damage pathway. In the future, the DRUGPATH-approach may help to predict novel pathway interactomes from high-content drug screens.
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Tamaño de la Célula/efectos de los fármacos , Biología Computacional/métodos , Daño del ADN , Inhibidores Enzimáticos/farmacología , Apoptosis/efectos de los fármacos , Proteínas de la Ataxia Telangiectasia Mutada/antagonistas & inhibidores , Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Dimetilsulfóxido/farmacología , Células Madre Embrionarias Humanas , Humanos , Indazoles/farmacología , Células Madre Pluripotentes Inducidas , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Sulfonamidas/farmacologíaRESUMEN
Transforming growth factor (TGF)-ß suppresses early hepatocellular carcinoma (HCC) development but triggers pro-oncogenic abilities at later stages. Recent data suggest that the receptor tyrosine kinase Axl causes a TGF-ß switch toward dedifferentiation and invasion of HCC cells. Here, we analyzed two human cellular HCC models with opposing phenotypes in response to TGF-ß. Both HCC models showed reduced proliferation and clonogenic growth behavior following TGF-ß stimulation, although they exhibited differences in chemosensitivity and migratory abilities, suggesting that HCC cells evade traits of anti-oncogenic TGF-ß. Transcriptome profiling revealed differential regulation of the chemokine CXCL5, which positively correlated with TGF-ß expression in HCC patients. The expression and secretion of CXCL5 was dependent on Axl expression, suggesting that CXCL5 is a TGF-ß target gene collaborating with Axl signaling. Loss of either TGF-ß or Axl signaling abrogated CXCL5-dependent attraction of neutrophils. In mice, tumor formation of transplanted HCC cells relied on CXCL5 expression. In HCC patients, high levels of Axl and CXCL5 correlated with advanced tumor stages, recruitment of neutrophils into HCC tissue, and reduced survival. Conclusion: The synergy of TGF-ß and Axl induces CXCL5 secretion, causing the infiltration of neutrophils into HCC tissue. Intervention with TGF-ß/Axl/CXCL5 signaling may be an effective therapeutic strategy to combat HCC progression in TGF-ß-positive patients.
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Carcinoma Hepatocelular/inmunología , Quimiocina CXCL5/fisiología , Neoplasias Hepáticas/inmunología , Infiltración Neutrófila , Proteínas Proto-Oncogénicas/fisiología , Proteínas Tirosina Quinasas Receptoras/fisiología , Factor de Crecimiento Transformador beta/fisiología , Animales , Humanos , Ratones , Células Tumorales Cultivadas , Tirosina Quinasa del Receptor AxlRESUMEN
Treatment of high-risk patients is a major challenge in multiple myeloma. This is especially true for patients assigned to the gene expression profiling-defined proliferation subgroup. Although recent efforts have identified some key players of proliferative myeloma, genetic interactions and players that can be targeted with clinically effective drugs have to be identified in order to overcome the poor prognosis of these patients. We therefore examined maternal embryonic leucine zipper kinase (MELK) for its implications in hyper-proliferative myeloma and analyzed the activity of the MELK inhibitor OTSSP167 both in vitro and in vivoMELK was found to be significantly overexpressed in the proliferative subgroup of myeloma. This finding translated into poor overall survival in patients with high vs low MELK expression. Enrichment analysis of upregulated genes in myeloma cells of MELKhigh patients confirmed the strong implications in myeloma cell proliferation. Targeting MELK with OTSSP167 impaired the growth and survival of myeloma cells, thereby affecting central survival factors such as MCL-1 and IRF4 This activity was also observed in the 5TGM.1 murine model of myeloma. OTSSP167 reduced bone marrow infiltration and serum paraprotein levels in a dose-dependent manner. In addition, we revealed a strong link between MELK and other proliferation-associated high-risk genes (PLK-1, EZH2, FOXM1, DEPDC1) and MELK inhibition also impaired the expression of those genes. We therefore conclude that MELK is an essential component of a proliferative gene signature and that pharmacological inhibition of MELK represents an attractive novel approach to overcome the poor prognosis of high-risk patients with a proliferative expression pattern.
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Proliferación Celular/efectos de los fármacos , Mieloma Múltiple/tratamiento farmacológico , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Animales , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Humanos , Ratones , Mieloma Múltiple/patología , Naftiridinas/farmacología , Pronóstico , Proteínas Serina-Treonina Quinasas/metabolismo , Medición de RiesgoRESUMEN
Immunohistochemical (IHC) determination of receptor status in breast cancer patients is frequently inaccurate. Since it directs the choice of systemic therapy, it is essential to increase its reliability. We increase the validity of IHC receptor expression by additionally considering gene expression (GE) measurements. Crisp therapeutic decisions are based on IHC estimates, even if they are borderline reliable. We further improve decision quality by a responsibility function, defining a critical domain for gene expression. Refined normalization is devised to file any newly diagnosed patient into existing data bases. Our approach renders receptor estimates more reliable by identifying patients with questionable receptor status. The approach is also more efficient since the rate of conclusive samples is increased. We have curated and evaluated gene expression data, together with clinical information, from 2880 breast cancer patients. Combining IHC with gene expression information yields a method more reliable and also more efficient as compared to common practice up to now. Several types of possibly suboptimal treatment allocations, based on IHC receptor status alone, are enumerated. A 'therapy allocation check' identifies patients possibly miss-classified. Estrogen: false negative 8%, false positive 6%. Progesterone: false negative 14%, false positive 11%. HER2: false negative 2%, false positive 50%. Possible implications are discussed. We propose an 'expression look-up-plot', allowing for a significant potential to improve the quality of precision medicine. Methods are developed and exemplified here for breast cancer patients, but they may readily be transferred to diagnostic data relevant for therapeutic decisions in other fields of oncology.
RESUMEN
The entry of malignant hepatocytes into blood vessels is a key step in the dissemination and metastasis of hepatocellular carcinoma (HCC). The identification of molecular mechanisms involved in the transmigration of malignant hepatocytes through the endothelial barrier is of high relevance for therapeutic intervention and metastasis prevention. In this study, we employed a model of hepatocellular transmigration that mimics vascular invasion using hepatic sinusoidal endothelial cells and malignant hepatocytes evincing a mesenchymal-like, invasive phenotype by transforming growth factor (TGF)-ß. Labelling of respective cell populations with various stable isotopes and subsequent mass spectrometry analyses allowed the "real-time" detection of molecular changes in both transmigrating hepatocytes and endothelial cells. Interestingly, the proteome profiling revealed 36 and 559 regulated proteins in hepatocytes and endothelial cells, respectively, indicating significant changes during active transmigration that mostly depends on cell-cell interaction rather than on TGF-ß alone. Importantly, matching these in vitro findings with HCC patient data revealed a panel of common molecular alterations including peroxiredoxin-3, epoxide hydrolase, transgelin-2 and collectin 12 that are clinically relevant for the patient's survival. We conclude that hepatocellular plasticity induced by TGF-ß is crucially involved in blood vessel invasion of HCC cells.
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Vasos Sanguíneos/patología , Carcinoma Hepatocelular/patología , Hepatocitos/patología , Neoplasias Hepáticas Experimentales/patología , Migración Transendotelial y Transepitelial , Factor de Crecimiento Transformador beta1/fisiología , Animales , Biomarcadores de Tumor/análisis , Comunicación Celular , Línea Celular Transformada , Movimiento Celular , Células Epiteliales/química , Células Epiteliales/patología , Transición Epitelial-Mesenquimal/fisiología , Hepatocitos/química , Humanos , Ratones , Proteoma/análisis , Proteoma/genética , Factor de Crecimiento Transformador beta1/antagonistas & inhibidores , Factor de Crecimiento Transformador beta1/genética , Factor de Crecimiento Transformador beta1/farmacologíaRESUMEN
Immunomodulatory drugs (IMiDs) are a cornerstone in the treatment of multiple myeloma (MM), but specific markers to predict outcome are still missing. Recent work pointed to a prognostic role for IMiD target genes (e.g. CRBN). Moreover, indirect activity of IMiDs on immune cells correlated with outcome, raising the possibility that cell populations in the bone marrow (BM) microenvironment could serve as biomarkers. We therefore analysed gene expression levels of six IMiD target genes in whole BM samples of 44 myeloma patients treated with lenalidomide-dexamethasone. Expression of CRBN (R = 0.30, P = .05), IKZF1 (R = 0.31, P = .04), IRF4 (R = 0.38, P = .01), MCT-1 (R = 0.30, P = .05), and CD147 (R = 0.38, P = .01), but not IKZF3 (R = -0.15, P = .34), was significantly associated with response. Interestingly, IKZF1 expression was elevated in BM environmental cells and thus selected for further investigation by multicolor flow cytometry. High IKAROS protein levels in total BM mononuclear cells (median OS 83.4 vs. 32.2 months, P = .02), CD19+ B cells (median OS 71.1 vs. 32.2 months, P = .05), CD3+ CD8+ T cells (median OS 83.4 vs 19.0 months, P = .008) as well as monocytes (median OS 53.9 vs 18.0 months, P = .009) were associated with superior overall survival (OS). In contrast, IKAROS protein expression in MM cells was not predictive for OS. Our data therefore corroborate the central role of immune cells for the clinical activity of IMiDs and built the groundwork for prospective analysis of IKAROS protein levels in distinct cell populations as a potential biomarker for IMiD based therapies.
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Biomarcadores de Tumor/análisis , Células de la Médula Ósea/química , Factor de Transcripción Ikaros/análisis , Factores Inmunológicos/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Dexametasona/uso terapéutico , Expresión Génica , Humanos , Factor de Transcripción Ikaros/metabolismo , Factores Inmunológicos/genética , Lenalidomida , Mieloma Múltiple/mortalidad , Mieloma Múltiple/patología , Tasa de Supervivencia , Talidomida/análogos & derivados , Talidomida/uso terapéutico , Resultado del TratamientoRESUMEN
Thymoma and thymic carcinoma are thymic epithelial tumors (TETs). We performed a molecular profiling to investigate the pathogenesis of TETs and identify novel targets for therapy. We analyzed 37 thymomas (18 type A, 19 type B3) and 35 thymic carcinomas. The sequencing of 50 genes detected nonsynonymous mutations in 16 carcinomas affecting ALK, ATM, CDKN2A, ERBB4, FGFR3, KIT, NRAS and TP53. Only two B3 thymomas had a mutation in noncoding regions of the SMARCB1 and STK11 gene respectively. Three type A thymomas harbored a nonsynonymous HRAS mutation. Fluorescence in situ hybridization detected in 38 % of carcinomas a CDKN2A, in 32 % a TP53 and in 8 % an ATM gene deletion, whereas only one B3 thymoma exhibited a CDKNA deletion, and none of the type A thymomas showed a gene loss. Sequencing of the total miRNA pool of 5 type A thymomas and 5 thymic carcinomas identified the C19MC miRNA cluster as highly expressed in type A thymomas, but completely silenced in thymic carcinomas. Furthermore, the miRNA cluster C14MC was downregulated in thymic carcinomas. Among non-clustered miRNAs, the upregulation of miR-21, miR-9-3 and miR-375 and the downregulation of miR-34b, miR-34c, miR-130a and miR-195 in thymic carcinomas were most significant. The expression of ALK, HER2, HER3, MET, phospho-mTOR, p16INK4A, PDGFRA, PDGFRB, PD-L1, PTEN and ROS1 was investigated by immunohistochemistry. PDGFRA was increased in thymic carcinomas and PD-L1 in B3 thymomas and thymic carcinomas. In summary, our results reveal genetic differences between thymomas and thymic carcinomas and suggest potential novel targets for therapy.
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Mutación/genética , Timoma/genética , Biomarcadores de Tumor/genética , Humanos , Inmunohistoquímica/métodos , Hibridación Fluorescente in Situ/métodos , MicroARNs/genética , Neoplasias Glandulares y Epiteliales/genética , Neoplasias del Timo/genéticaRESUMEN
Aging is associated with a progressive loss of the CD28 costimulatory molecule in CD4+ lymphocytes (CD28null T cells), which is accompanied by the acquisition of new biological and functional properties that give rise to an impaired immune response. The regulatory mechanisms that govern the appearance and function of this cell subset during aging and in several associated inflammatory disorders remain controversial. Here, we present the whole-genome DNA methylation and gene expression profiles of CD28null T cells and its CD28+ counterpart. A comparative analysis revealed that 296 genes are differentially methylated between the two cell subsets. A total of 160 genes associated with cytotoxicity (e.g. GRZB, TYROBP, and RUNX3) and cytokine/chemokine signaling (e.g. CX3CR1, CD27, and IL-1R) are demethylated in CD28null T cells, while 136 de novo-methylated genes matched defects in the TCR signaling pathway (e.g. ITK, TXK, CD3G, and LCK). TCR-landscape analysis confirmed that CD28null T cells have an oligo/monoclonal expansion over the polyclonal background of CD28+ T cells, but feature a Vß family repertoire specific to each individual. We reported that CD28null T cells show a preactivation state characterized by a higher level of expression of inflammasome-related genes that leads to the release of IL-1ß when activated. Overall, our results demonstrate that CD28null T cells have a unique DNA methylation landscape, which is associated with differences in gene expression, contributing to the functionality of these cells. Understanding these epigenetic regulatory mechanisms could suggest novel therapeutic strategies to prevent the accumulation and activation of these cells during aging.
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Antígenos CD28/metabolismo , Antígenos CD4/metabolismo , Linfocitos T CD4-Positivos/citología , Linfocitos T CD4-Positivos/inmunología , Senescencia Celular/genética , Senescencia Celular/inmunología , Metilación de ADN/genética , Genoma Humano , Apoptosis/genética , Islas de CpG/genética , Citotoxicidad Inmunológica , Regulación de la Expresión Génica , Humanos , Inmunidad , Inflamasomas/metabolismo , Fenotipo , Receptores de Antígenos de Linfocitos T/metabolismo , Reproducibilidad de los Resultados , Transducción de SeñalRESUMEN
Inflammatory chemo- and cytokines and matrix-degrading proteases underlie the progression of osteoarthritis (OA). Aiming to define upstream regulators for these disease markers, we pursued initial evidence for an upregulation of members of the adhesion/growth-regulatory galectin family. Immunohistochemical localization of galectin-3 (Gal-3) in sections of human cartilage with increasing levels of degeneration revealed a linear correlation reaching a chondrocyte positivity of 60%. Presence in situ was cytoplasmic, the lectin was secreted from OA chondrocytes in culture and binding of Gal-3 yielded lactose-inhibitable surface staining. Exposure of cells to the lectin led to enhanced gene expression and secretion of functional disease markers. Genome-wide transcriptomic analysis broadened this result to reveal a pro-degradative/inflammatory gene signature under the control of NF-κB. Fittingly, targeting this route of activation by inhibitors impaired the unfavourable response to Gal-3 binding, as also seen by shortening the lectin's collagen-like repeat region. Gal-3's activation profile overlaps with that of homodimeric galectin-1 (Gal-1) and also has distinctive (supplementing) features. Tested at subsaturating concentrations in a mixture, we found cooperation between the two galectins, apparently able to team up to promote OA pathogenesis. In summary, our results suggest that a network of endogenous lectins is relevant for initiating this process cascade.
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Condrocitos/metabolismo , Galectina 1/metabolismo , Galectina 3/metabolismo , Redes Reguladoras de Genes , Osteoartritis/patología , Anciano , Anciano de 80 o más Años , Proteínas Sanguíneas , Condrocitos/patología , Matriz Extracelular/metabolismo , Femenino , Galectinas , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Osteoartritis/genética , Osteoartritis/inmunología , Transducción de SeñalRESUMEN
BACKGROUND: The polycomb complex protein BMI-1 (BMI-1) is a putative oncogene reported to be overexpressed in multiple myeloma (MM). Silencing of BMI-1 was shown to impair the growth and survival of MM cells. However, therapeutic agents specifically targeting BMI-1 were not available so far. Here, we investigated PTC-209, a novel small molecule inhibitor of BMI-1, for its activity in MM. METHODS: BMI-1 expression was analysed in human MM cell lines and primary MM cells by using publically available gene expression profiling (GEP) data. The anti-MM activity of PTC-209 was investigated by viability testing, cell cycle analysis, annexin V and 7-AAD staining, quantification of cleaved poly(ADP-ribose) polymerase (PARP), JC-1 as well as colony formation assays. Deregulation of central myeloma growth and survival genes was studied by quantitative PCR and flow cytometry, respectively. In addition, the impact of PTC-209 on in vitro osteoclast, osteoblast and tube formation was analysed. RESULTS: We confirmed overexpression of BMI-1 in MM patients by using publically available GEP datasets. Of note, BMI-1 expression was further increased at relapse which translated into significantly shorter overall survival in relapsed/refractory patients treated with bortezomib or dexamethasone. Treatment with PTC-209 significantly decreased viable cell numbers in human MM cell lines, induced a G1 cell cycle arrest, promoted apoptosis and demonstrated synergistic activity with pomalidomide and carfilzomib. The anti-MM activity of PTC-209 was accompanied by a significant decrease of cyclin D1 (CCND1) and v-myc avian myelocytomatosis viral oncogene homolog (MYC) expression as well as upregulation of cyclin-dependent kinase inhibitor 1A (CDKN1A) and cyclin-dependent kinase inhibitor 1B (CDKN1B). We also observed upregulation of NOXA (up to 3.6 ± 1.2-fold induction, P = 0.009) and subsequent downregulation of myeloid cell leukemia 1 (MCL-1) protein levels, which likely mediates the apoptotic effects of PTC-209. Importantly, the anti-MM activity was upheld in the presence of stromal support or myeloma growth factors insulin-like growth factor 1 (IGF-1) and interleukin 6 (IL-6). In the MM microenvironment, PTC-209 impaired tube formation, impaired osteoclast development and decreased osteoblast formation in a dose-dependent manner (P < 0.01 at 1 µM, respectively). The latter might be attributed to an induction of DKK1 and was reversed by concurrent anti-DKK1 antibody treatment. CONCLUSIONS: We confirmed overexpression of BMI-1 in MM highlighting its role as an attractive drug target and reveal therapeutic targeting of BMI-1 by PTC-209 as a promising novel therapeutic intervention for MM.
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Compuestos Heterocíclicos con 2 Anillos/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Complejo Represivo Polycomb 1/antagonistas & inhibidores , Tiazoles/uso terapéutico , Microambiente Tumoral/efectos de los fármacos , Apoptosis/efectos de los fármacos , Apoptosis/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Células Cultivadas , Dexametasona/farmacología , Sinergismo Farmacológico , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Compuestos Heterocíclicos con 2 Anillos/farmacología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Células Endoteliales de la Vena Umbilical Humana/fisiología , Humanos , Mieloma Múltiple/genética , Mieloma Múltiple/metabolismo , Neovascularización Fisiológica/efectos de los fármacos , Neovascularización Fisiológica/genética , Oligopéptidos/farmacología , Osteogénesis/efectos de los fármacos , Osteogénesis/genética , Complejo Represivo Polycomb 1/genética , Complejo Represivo Polycomb 1/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Talidomida/análogos & derivados , Talidomida/farmacología , Tiazoles/farmacología , Microambiente Tumoral/genéticaRESUMEN
MAIN CONCLUSION: Multiple F3'5'H evolution from F3'H has occurred in dicotyledonous plants. Efficient pollinator attraction is probably the driving force behind, as this allowed for the synthesis of delphinidin-based blue anthocyanins. The cytochrome P450-dependent monooxygenases flavonoid 3'-hydroxylase (F3'H) and flavonoid 3',5'-hydroxylase (F3'5'H) hydroxylate the B-ring of flavonoids at the 3'- and 3'- and 5'-position, respectively. Their divergence took place early in plant evolution. While F3'H is ubiquitously present in higher plants, the distribution of F3'5'H is scattered. Here, we report that F3'5'H has repeatedly evolved from F3'H precursors at least four times in dicotyledonous plants: In the Asteraceae, we identified F3'5'Hs specific for the subfamilies Cichorioideae and Asteroideae, and additionally an F3'5'H that seems to be specific for the genus Echinops of the subfamily Carduoideae; moreover, characterisation of a sequence from Billardiera heterophylla (formerly Sollya heterophylla) (Pittosporaceae) showed that the independent evolution of an F3'5'H has occurred at least once also in another family. The evolution of F3'5'H from an F3'H precursor represents a gain of enzymatic function, probably triggered by an amino acid change at one position of substrate recognition site 6. The gain of F3'5'H activity allows for the synthesis of delphinidin-based anthocyanins which usually provide the basis for lilac to blue flower colours. Therefore, the need for an efficient pollinator attraction is probably the driving force behind the multiple F3'5'H evolution.
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Sistema Enzimático del Citocromo P-450/metabolismo , Evolución Molecular , Sistema Enzimático del Citocromo P-450/genética , Regulación de la Expresión Génica de las PlantasRESUMEN
Aging, a time-dependent functional decline of biological processes, is the primary risk factor in developing diseases such as cancer, cardiovascular or degenerative diseases. There is a real need to understand the human aging process in order to increase the length of disease-free life, also known as "health span". Accumulation of progerin and prelamin A are the hallmark of a group of premature aging diseases but have also been found during normal cellular aging strongly suggesting similar mechanisms between healthy aging and LMNA-linked progeroid syndromes. How this toxic accumulation contributes to aging (physiological or pathological) remains unclear. Since affected tissues in age-associated disorders and in pathological aging are mainly of mesenchymal origin we propose a model of human aging based on mesenchymal stem cells (hMSCs) which accumulate prelamin A. We demonstrate that prelamin A-accumulating hMSCs have a premature aging phenotype which affects their functional competence in vivo. The combination of prelamin A accumulation and stress conditions enhance the aging phenotype by dysregulating the activity of the octamer binding protein Oct-1This experimental model has been fundamental to identify a new role for Oct-1 in hMSCs aging.
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Autofagia/fisiología , Senescencia Celular/fisiología , Células Madre Mesenquimatosas/metabolismo , Proteínas Nucleares/metabolismo , Factor 1 de Transcripción de Unión a Octámeros/metabolismo , Precursores de Proteínas/metabolismo , Envejecimiento/metabolismo , Envejecimiento Prematuro/metabolismo , Animales , Western Blotting , Células Cultivadas , Técnica del Anticuerpo Fluorescente , Xenoinjertos , Humanos , Lamina Tipo A , Ratones , Ratones SCID , Análisis de Secuencia por Matrices de Oligonucleótidos , Especies Reactivas de Oxígeno/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Telómero/metabolismo , Telómero/patología , TranscriptomaRESUMEN
The discovery that the cells communicate through emission of vesicles has opened new opportunities for better understanding of physiological and pathological mechanisms. This discovery also provides a novel source for non-invasive disease biomarker research. Our group has previously reported that hepatocytes release extracellular vesicles with protein content reflecting the cell-type of origin. Here, we show that the extracellular vesicles released by hepatocytes also carry RNA. We report the messenger RNA composition of extracellular vesicles released in two non-tumoral hepatic models: primary culture of rat hepatocytes and a progenitor cell line obtained from a mouse foetal liver. We describe different subpopulations of extracellular vesicles with different densities and protein and RNA content. We also show that the RNA cargo of extracellular vesicles released by primary hepatocytes can be transferred to rat liver stellate-like cells and promote their activation. Finally, we provide in vitro and in vivo evidence that liver-damaging drugs galactosamine, acetaminophen, and diclofenac modify the RNA content of these vesicles. To summarize, we show that the extracellular vesicles secreted by hepatocytes contain various RNAs. These vesicles, likely to be involved in the activation of stellate cells, might become a new source for non-invasive identification of the liver toxicity markers.
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Matriz Extracelular/genética , Hepatocitos/fisiología , Vesículas Transportadoras/genética , Animales , Línea Celular , Células Estrelladas Hepáticas/citología , Células Estrelladas Hepáticas/fisiología , Hígado/citología , Hígado/fisiología , Masculino , Ratones , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley , Células Madre/fisiología , TranscriptomaRESUMEN
Early-onset prostate cancer (EO-PCA) represents the earliest clinical manifestation of prostate cancer. To compare the genomic alteration landscapes of EO-PCA with "classical" (elderly-onset) PCA, we performed deep sequencing-based genomics analyses in 11 tumors diagnosed at young age, and pursued comparative assessments with seven elderly-onset PCA genomes. Remarkable age-related differences in structural rearrangement (SR) formation became evident, suggesting distinct disease pathomechanisms. Whereas EO-PCAs harbored a prevalence of balanced SRs, with a specific abundance of androgen-regulated ETS gene fusions including TMPRSS2:ERG, elderly-onset PCAs displayed primarily non-androgen-associated SRs. Data from a validation cohort of > 10,000 patients showed age-dependent androgen receptor levels and a prevalence of SRs affecting androgen-regulated genes, further substantiating the activity of a characteristic "androgen-type" pathomechanism in EO-PCA.
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Reordenamiento Génico , Genómica , Proteínas de Fusión Oncogénica/genética , Neoplasias de la Próstata/genética , Receptores Androgénicos/genética , Serina Endopeptidasas/genética , Transactivadores/genética , Adulto , Anciano , Anciano de 80 o más Años , Biología Computacional , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Regulador Transcripcional ERGRESUMEN
UNLABELLED: Susceptibility to develop nonalcoholic fatty liver disease (NAFLD) has genetic bases, but the associated variants are uncertain. The aim of the present study was to identify genetic variants that could help to prognose and further understand the genetics and development of NAFLD. Allele frequencies of 3,072 single-nucleotide polymorphisms (SNPs) in 92 genes were characterized in 69 NAFLD patients and 217 healthy individuals. The markers that showed significant allele-frequency differences in the pilot groups were subsequently studied in 451 NAFLD patients and 304 healthy controls. Besides this, 4,414 type 2 diabetes mellitus (T2DM) cases and 4,567 controls were genotyped. Liver expression of the associated gene was measured and the effect of its potential role was studied by silencing the gene in vitro. Whole genome expression, oxidative stress (OS), and the consequences of oleic acid (OA)-enriched medium on lipid accumulation in siSLC2A1-THLE2 cells were studied by gene-expression analysis, dihydroethidium staining, BODIPY, and quantification of intracellular triglyceride content, respectively. Several SNPs of SLC2A1 (solute carrier family 2 [facilitated glucose transporter] member 1) showed association with NAFLD, but not with T2DM, being the haplotype containing the minor allele of SLC2A1 sequence related to the susceptibility to develop NAFLD. Gene-expression analysis demonstrated a significant down-regulation of SLC2A1 in NAFLD livers. Enrichment functional analyses of transcriptome profiles drove us to demonstrate that in vitro silencing of SLC2A1 induces an increased OS activity and a higher lipid accumulation under OA treatment. CONCLUSIONS: Genetic variants of SLC2A1 are associated with NAFLD, and in vitro down-regulation of this gene promotes lipid accumulation. Moreover, the oxidative response detected in siSLC2A1-THLE2 cells corroborated the antioxidant properties previously related to this gene and linked the most representative clinical characteristics of NAFLD patients: oxidative injury and increased lipid storage.
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Hígado Graso/genética , Transportador de Glucosa de Tipo 1/genética , Adolescente , Adulto , Anciano , Diabetes Mellitus Tipo 2/genética , Femenino , Frecuencia de los Genes , Silenciador del Gen , Predisposición Genética a la Enfermedad , Transportador de Glucosa de Tipo 1/biosíntesis , Humanos , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico , Ácido Oléico/farmacología , Estrés Oxidativo/genética , Polimorfismo de Nucleótido Simple , TranscriptomaRESUMEN
Lamin A (LMNA)-linked lipodystrophies may be either genetic (associated with LMNA mutations) or acquired (associated with the use of human immunodeficiency virus protease inhibitors [PIs]), and in both cases they share clinical features such as anomalous distribution of body fat or generalized loss of adipose tissue, metabolic alterations, and early cardiovascular complications. Both LMNA-linked lipodystrophies are characterized by the accumulation of the lamin A precursor prelamin A. The pathological mechanism by which prelamin A accumulation induces the lipodystrophy associated phenotypes remains unclear. Since the affected tissues in these disorders are of mesenchymal origin, we have generated an LMNA-linked experimental model using human mesenchymal stem cells treated with a PI, which recapitulates the phenotypes observed in patient biopsies. This model has been demonstrated to be a useful tool to unravel the pathological mechanism of the LMNA-linked lipodystrophies, providing an ideal system to identify potential targets to generate new therapies for drug discovery screening. We report for the first time that impaired adipogenesis is a consequence of the interaction between accumulated prelamin A and Sp1 transcription factor, sequestration of which results in altered extracellular matrix gene expression. In fact, our study shows a novel, essential, and finely tuned role for Sp1 in adipose lineage differentiation in human mesenchymal stem cells. These findings define a new physiological experimental model to elucidate the pathological mechanisms LMNA-linked lipodystrophies, creating new opportunities for research and treatment not only of LMNA-linked lipodystrophies but also of other adipogenesis-associated metabolic diseases.
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Tejido Adiposo/metabolismo , Diferenciación Celular/fisiología , Metabolismo de los Lípidos/fisiología , Células Madre Mesenquimatosas/metabolismo , Proteínas Nucleares/biosíntesis , Precursores de Proteínas/biosíntesis , Vesículas Secretoras/metabolismo , Factor de Transcripción Sp1/metabolismo , Adipogénesis/fisiología , Tejido Adiposo/citología , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Regulación de la Expresión Génica/genética , Humanos , Lamina Tipo A , Lipodistrofia/genética , Lipodistrofia/metabolismo , Lipodistrofia/patología , Células Madre Mesenquimatosas/citología , Mutación , Proteínas Nucleares/genética , Precursores de Proteínas/genética , Vesículas Secretoras/genética , Factor de Transcripción Sp1/genéticaRESUMEN
BACKGROUND: More than 20,000 cultivars of garden dahlia (Dahlia variabilis hort.) are available showing flower colour from white, yellow and orange to every imaginable hue of red and purple tones. Thereof, only a handful of cultivars are so-called black dahlias showing distinct black-red tints. Flower colour in dahlia is a result of the accumulation of red anthocyanins, yellow anthochlors (6'-deoxychalcones and 4-deoxyaurones) and colourless flavones and flavonols, which act as copigments. White and yellow coloration occurs only if the pathway leading to anthocyanins is incomplete. Not in all cultivars the same step of the anthocyanin pathway is affected, but the lack of dihydroflavonol 4-reductase activity is frequently observed and this seems to be based on the suppression of the transcription factor DvIVS. The hitherto unknown molecular background for black colour in dahlia is here presented. RESULTS: Black cultivars accumulate high amounts of anthocyanins, but show drastically reduced flavone contents. High activities were observed for all enzymes from the anthocyanin pathway whereas FNS II activity could not be detected or only to a low extent in 13 of 14 cultivars. cDNA clones and genomic clones of FNS II were isolated. Independently from the colour type, heterologous expression of the cDNA clones resulted in functionally active enzymes. FNS II possesses one intron of varying length. Quantitative Real-time PCR showed that FNS II expression in black cultivars is low compared to other cultivars. No differences between black and red cultivars were observed in the expression of transcription factors IVS and possible regulatory genes WDR1, WDR2, MYB1, MYB2, 3RMYB and DEL or the structural genes of the flavonoid pathway. Despite the suppression of FHT expression, flavanone 3-hydroxylase (FHT, synonym F3H) enzyme activity was clearly present in the yellow and white cultivars. CONCLUSIONS: An increased accumulation of anthocyanins establishes the black flowering phenotypes. In the majority of black cultivars this is due to decreased flavone accumulation and thus a lack of competition for flavanones as the common precursors of flavone formation and the anthocyanin pathway. The low FNS II activity is reflected by decreased FNS II expression.
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Antocianinas/biosíntesis , Sistema Enzimático del Citocromo P-450/metabolismo , Dahlia/enzimología , Flavonas/biosíntesis , Flores/enzimología , Pigmentación/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Sistema Enzimático del Citocromo P-450/genética , ADN Complementario/genética , Dahlia/genética , Flores/genética , Regulación de la Expresión Génica de las Plantas , Datos de Secuencia Molecular , Fenotipo , Alineación de SecuenciaRESUMEN
Onobrychis viciifolia (sainfoin) is a traditional fodder legume showing multiple benefits for the environment, animal health and productivity but weaker agronomic performance in comparison to other legumes. Benefits can be mainly ascribed to the presence of polyphenols. The polyphenol metabolism in O. viciifolia was studied at the level of gene expression, enzyme activity, polyphenol accumulation and antioxidant activity. A screening of 37 accessions regarding each of these characters showed a huge variability between individual samples. Principal component analysis revealed that flavonols and flavan 3-ols are the most relevant variables for discrimination of the accessions. The determination of the activities of dihydroflavonol 4-reductase and flavonol synthase provides a suitable screening tool for the estimation of the ratio of flavonols to flavan 3-ols and can be used for the selection of samples from those varieties that have a specific optimal ratio of these compounds for further breeding.