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1.
RNA Biol ; 19(1): 1305-1315, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-36469564

RESUMEN

The microRNA-200 family has wide-ranging regulatory functions in cancer development and progression. Above all, it is strongly associated with the epithelial-to-mesenchymal transition (EMT), a process during which cells change their epithelial to a mesenchymal phenotype and acquire invasive characteristics. More recently, miR-200 family members have also been reported to impact the immune evasion of cancer cells by regulating the expression of immunoinhibitory immune checkpoints (ICs) like PD-L1. Therefore, we aimed to comprehensively characterize this miR-200 family as a regulatory interface between EMT and immune evasion mechanisms in biliary tract cancer. Initial correlation analyses and transient overexpression experiments using miRNA mimics suggested miR-200c-3p as a putative regulator of ICs including PD-L1, LGALS9, and IDO1. However, these effects could not be confirmed in stable miR-200c-3p overexpression cell lines, nor in cells transiently transfected with miR-200c-3p mimic from an independent manufacturer. By shifting our efforts towards dissecting the mechanisms leading to these disparate effects, we observed that the initially used miR-200c-3p mimic triggered a double-stranded (ds)RNA-dependent antiviral response. Besides upregulating the ICs, this had substantial cellular consequences including an induction of interferon type I and type III expression, increased levels of intracellular dsRNA sensors, and a significantly altered cellular growth and apoptotic activity.Our study highlights the capability of miRNA mimics to non-specifically induce a dsRNA-mediated antiviral interferon response. Consequently, phenotypic alterations crucially distort physiological miRNA functions and might result in a major misinterpretation of previous and future miRNA studies, especially in the context of IC regulation.


Asunto(s)
MicroARNs , MicroARNs/metabolismo , Interferones/genética , Interferones/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Transición Epitelial-Mesenquimal/genética , Proliferación Celular , Antivirales/farmacología , Regulación Neoplásica de la Expresión Génica , Línea Celular Tumoral
2.
Int J Mol Sci ; 20(21)2019 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-31652839

RESUMEN

The liver is the central metabolic organ of mammals. In humans, most diseases of the liver are primarily caused by an unhealthy lifestyle-high fat diet, drug and alcohol consumption- or due to infections and exposure to toxic substances like aflatoxin or other environmental factors. All these noxae cause changes in the metabolism of functional cells in the liver. In this literature review we focus on the changes at the miRNA level, the formation and impact of reactive oxygen species and the crosstalk between those factors. Both, miRNAs and oxidative stress are involved in the multifactorial development and progression of acute and chronic liver diseases, as well as in viral hepatitis and carcinogenesis, by influencing numerous signaling and metabolic pathways. Furthermore, expression patterns of miRNAs and antioxidants can be used for biomonitoring the course of disease and show potential to serve as possible therapeutic targets.


Asunto(s)
Hepatopatías/etiología , Hígado/metabolismo , MicroARNs/genética , Estrés Oxidativo , Carcinogénesis/metabolismo , Humanos , Hepatopatías/patología , MicroARNs/metabolismo
3.
Int J Mol Sci ; 20(14)2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31311135

RESUMEN

Many cell types express an acid-sensitive outwardly rectifying (ASOR) anion current of an unknown function. We characterized such a current in BV-2 microglial cells and then studied its interrelation with the volume-sensitive outwardly rectifying (VSOR) Cl- current and the effect of acidosis on cell volume regulation. We used patch clamp, the Coulter method, and the pH-sensitive dye BCECF to measure Cl- currents and cell membrane potentials, mean cell volume, and intracellular pH, respectively. The ASOR current activated at pH ≤ 5.0 and displayed an I- > Cl- > gluconate- permeability sequence. When compared to the VSOR current, it was similarly sensitive to DIDS, but less sensitive to DCPIB, and insensitive to tamoxifen. Under acidic conditions, the ASOR current was the dominating Cl- conductance, while the VSOR current was apparently inactivated. Acidification caused cell swelling under isotonic conditions and prevented the regulatory volume decrease under hypotonicity. We conclude that acidification, associated with activation of the ASOR- and inactivation of the VSOR current, massively impairs cell volume homeostasis. ASOR current activation could affect microglial function under acidotoxic conditions, since acidosis is a hallmark of pathophysiological events like inflammation, stroke or ischemia and migration and phagocytosis in microglial cells are closely related to cell volume regulation.


Asunto(s)
Canales de Cloruro/metabolismo , Microglía/metabolismo , Potenciales de Acción , Animales , Línea Celular , Cloruros/metabolismo , Concentración de Iones de Hidrógeno , Yodo/metabolismo , Transporte Iónico , Ratones , Microglía/fisiología , Presión Osmótica
4.
Cell Physiol Biochem ; 50(4): 1460-1473, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30359963

RESUMEN

BACKGROUND/AIMS: The neutral, non-essential amino acid glycine has manifold functions and effects under physiological and pathophysiological conditions. Besides its function as a neurotransmitter in the central nervous system, glycine also exerts immunomodulatory effects and as an osmolyte it participates in cell volume regulation. During phagocytosis, glycine contributes to (local) cell volume-dependent processes like lamellipodium formation. Similar to the expansion of the lamellipodium we assume that glycine also affects the migration of microglial cells in a cell volume-dependent manner. METHODS: Mean cell volume (MCV) and cell migration were determined using flow cytometry and trans-well migration assays, respectively. Electrophysiological recordings of the cell membrane potential (Vmem) and swelling-dependent chloride (Cl-) currents (IClswell, VSOR, VRAC) were performed using the whole-cell patch clamp technique. RESULTS: In the murine microglial cell line BV-2, flow cytometry analysis revealed that glycine (5 mM) increases the MCV by ∼9%. The glycine-dependent increase in MCV was suppressed by the partial sodium-dependent neutral amino acid transporter (SNAT) antagonist MeAIB and augmented by the Cl- current blocker DCPIB. Electrophysiological recordings showed that addition of glycine activates a Cl- current under isotonic conditions resembling features of the swelling-activated Cl- current (IClswell). The cell membrane potential (Vmem) displayed a distinctive time course after glycine application; initially, glycine evoked a rapid depolarization mediated by Na+-coupled glycine uptake via SNAT, followed by a further gradual depolarization, which was fully suppressed by DCPIB. Interestingly, glycine significantly increased migration of BV-2 cells, which was suppressed by MeAIB, suggesting that SNAT is involved in the migration process of microglial cells. CONCLUSION: We conclude that glycine acts as a chemoattractant for microglial cells presumably by a cell volume-dependent mechanism involving SNAT-mediated cell swelling.


Asunto(s)
Sistema de Transporte de Aminoácidos A/metabolismo , Tamaño de la Célula/efectos de los fármacos , Glicina/farmacología , Sistema de Transporte de Aminoácidos A/antagonistas & inhibidores , Animales , Línea Celular , Movimiento Celular/efectos de los fármacos , Cloruros/metabolismo , Ciclopentanos/farmacología , Soluciones Hipotónicas/farmacología , Indanos/farmacología , Potenciales de la Membrana/efectos de los fármacos , Ratones , Microglía/citología , Microglía/metabolismo , Nitrobenzoatos/farmacología , Técnicas de Placa-Clamp
5.
Dig Endosc ; 30(3): 354-363, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29218732

RESUMEN

BACKGROUND AND AIM: Colorectal endoscopic submucosal dissection (ESD) shows higher R0 resection and lower local recurrence rates than endoscopic mucosal resection (EMR) in Japan. In Europe, independent learning of ESD in the colorectum is feasible, but yet to be analyzed for curative resection and recurrence rates. METHODS: After experimental training under supervision by Japanese experts (T.O., N.Y.), three endoscopists independently carried out 83 ESD procedures intention-to-treat for lesions in the entire colorectum of 67 patients in a prospective registry (November 2009 to June 2016). RESULTS: ESD was feasible in 80 (96%) colorectal neoplasias (mean diameter 33.6 [± 1.8] mm), and three more required conversion to piecemeal EMR. The lesions were adenomas in 66% with low-grade intraepithelial neoplasia (LGIN), 29% with high-grade intraepithelial neoplasia, and 5% with carcinomas (G2, pT1). ESD had to be facilitated by the final use of snaring (hybrid-ESD, n = 45), especially in the initial learning period. En-bloc resection rate was 85%. Complications were microperforations (7%, conducive to one hemicolectomy), and delayed bleeding (1%) without mortality or long-term morbidity. Residual adenomas with LGIN (5%) after hybrid-ESD did not recur after endoscopic ablation. All malignant neoplasias (34%) were curatively resected without recurrence after a mean follow up of 19.5 (± 3.2) months. CONCLUSIONS: During independent ESD learning in the colorectum, ESD intention-to-treat showed a low recurrence rate after appropriate training, and hybrid-ESD showed acceptable complication and recurrence rates, justifying hybrid-ESD as a strategy for self-completion and rescue.


Asunto(s)
Adenoma/cirugía , Carcinoma/cirugía , Neoplasias Colorrectales/cirugía , Resección Endoscópica de la Mucosa , Recurrencia Local de Neoplasia/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
6.
Int J Mol Sci ; 19(3)2018 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-29510509

RESUMEN

The clonogenic assay is a widely used method to study the ability of cells to 'infinitely' produce progeny and is, therefore, used as a tool in tumor biology to measure tumor-initiating capacity and stem cell status. However, the standard protocol of using 6-well plates has several disadvantages. By miniaturizing the assay to a 96-well microplate format, as well as by utilizing the confluence detection function of a multimode reader, we here describe a new and modified protocol that allows comprehensive experimental setups and a non-endpoint, label-free semi-automatic analysis. Comparison of bright field images with confluence images demonstrated robust and reproducible detection of clones by the confluence detection function. Moreover, time-resolved non-endpoint confluence measurement of the same well showed that semi-automatic analysis was suitable for determining the mean size and colony number. By treating cells with an inhibitor of clonogenic growth (PTC-209), we show that our modified protocol is suitable for comprehensive (broad concentration range, addition of technical replicates) concentration- and time-resolved analysis of the effect of substances or treatments on clonogenic growth. In summary, this protocol represents a time- and cost-effective alternative to the commonly used 6-well protocol (with endpoint staining) and also provides additional information about the kinetics of clonogenic growth.


Asunto(s)
Miniaturización/métodos , Ensayo de Tumor de Célula Madre/métodos , Línea Celular Tumoral , Citostáticos/toxicidad , Compuestos Heterocíclicos con 2 Anillos/toxicidad , Humanos , Tiazoles/toxicidad
7.
Int J Mol Sci ; 19(9)2018 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-30223590

RESUMEN

Epigenetic factors are essentially involved in carcinogenesis, tumor promotion, and chemoresistance. Two epigenetic key players are miRNAs and histone deacetylases (HDACs). As previously shown by own theoretical databank analysis, the crosstalk between miRNAs and HDACs is relevant in different human chronic diseases and cancerogenic pathways. We aimed to investigate a potential connection between the expression of a well-defined subset of "proliferation-associated" miRNAs and the expression of HDACs as well as clinical parameters in pancreatic neuroendocrine tumors (pNETs). MATERIALS AND METHODS: Expression levels of miRNA132-3p, miRNA145-5p, miRNA183-5p, miRNA34a-5p, and miRNA449a in 57 pNETs resected between 1997 and 2015 were measured and linked to the immunohistochemical expression pattern of members of the four HDAC classes on human tissue microarrays. All pNET cases were clinically and pathologically characterized according to published guidelines. Correlation analysis revealed a significant association between expression of specific miRNAs and two members of the HDAC family (HDAC3 and HDAC4). Additionally, a linkage between miRNA expression and clinico-pathological parameters like grading, TNM-staging, and hormone activity was found. Moreover, overall and disease-free survival is statistically correlated with the expression of the investigated miRNAs. Overall, we demonstrated that specific miRNAs could be linked to HDAC expression in pNETs. Especially miRNA449a (associated with HDAC3/4) seems to play an important role in pNET proliferation and could be a potential prognostic factor for poor survival. These first data could help, to improve our knowledge of the complex interactions of the epigenetic drivers in pNETs for further therapeutic approaches.


Asunto(s)
Carcinoma Neuroendocrino/genética , Carcinoma Neuroendocrino/metabolismo , Regulación Neoplásica de la Expresión Génica , Histona Desacetilasas/metabolismo , MicroARNs/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Anciano , Biomarcadores de Tumor , Carcinoma Neuroendocrino/diagnóstico , Carcinoma Neuroendocrino/mortalidad , Línea Celular Tumoral , Proliferación Celular , Epigénesis Genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/mortalidad , Pronóstico
8.
Int J Mol Sci ; 19(10)2018 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-30321986

RESUMEN

Histone deacetylases (HDACs) play a key role in epigenetic mechanisms in health and disease and their dysfunction is implied in several cancer entities. Analysis of expression patterns in pancreatic neuroendocrine tumors (pNETs) indicated HDAC5 to be a potential target for future therapies. As a first step towards a possible treatment, the aim of this study was to evaluate the in vitro cellular and molecular effects of HDAC5 inhibition in pNET cells. Two pNET cell lines, BON-1 and QGP-1, were incubated with different concentrations of the selective class IIA HDAC inhibitor, LMK-235. Effects on cell viability were determined using the resazurin-assay, the caspase-assay, and Annexin-V staining. Western Blot and immunofluorescence microscopy were performed to assess the effects on HDAC5 functionality. LMK-235 lowered overall cell viability by inducing apoptosis in a dose- and time-dependent manner. Furthermore, acetylation of histone-H3 increased with higher LMK-235 concentrations, indicating functional inhibition of HDAC4/5. Immunocytochemical analysis showed that proliferative activity (phosphohistone H3 and Ki-67) decreased at highest concentrations of LMK-235 while chromogranin and somatostatin receptor 2 (SSTR2) expression increased in a dose-dependent manner. HDAC5 expression was found to be largely unaffected by LMK-235. These findings indicate LMK-235 to be a potential therapeutic approach for the development of an effective and selective pNET treatment.


Asunto(s)
Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/metabolismo , Tumores Neuroendocrinos/metabolismo , Neoplasias Pancreáticas/metabolismo , Acetilación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Histonas/metabolismo , Humanos , Tumores Neuroendocrinos/tratamiento farmacológico , Neoplasias Pancreáticas/tratamiento farmacológico , Proteínas Represoras/metabolismo
9.
Cell Physiol Biochem ; 41(3): 1011-1019, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28291963

RESUMEN

BACKGROUND/AIMS: For in vitro cytotoxicity testing, discrimination of apoptosis and necrosis represents valuable information. Viability analysis performed at two different time points post treatment could serve such a purpose because the dynamics of metabolic activity of apoptotic and necrotic cells is different, i.e. a more rapid decline of cellular metabolism during necrosis whereas cellular metabolism is maintained during the entire execution phase of apoptosis. This study describes a straightforward approach to distinguish apoptosis and necrosis. METHODS: A431 human epidermoid carcinoma cells were treated with different concentrations/doses of actinomycin D (Act-D), 4,5,6,7-tetrabromo-2-azabenzimidazole (TBB), Ro 31-8220, H2O2 and photodynamic treatment (PDT). The resazurin viability signal was recorded at 2 and 24 hrs post treatment. Apoptosis and necrosis were verified by measuring caspase 3/7 and membrane integrity. RESULTS: Calculation of the difference curve between the 2 and 24 hrs resazurin signals yields the following information: a positive difference signal indicates apoptosis (i.e. high metabolic activity at early time points and low signal at 24 hrs post treatment) while an early reduction of the viability signal indicates necrosis. For all treatments, this dose-dependent sequence of cellular responses could be confirmed by independent assays. CONCLUSION: Simple and cost-effective viability analysis provides reliable information about the dose ranges of a cytotoxic agent where apoptosis or necrosis occurs. This may serve as a starting point for further in-depth characterisation of cytotoxic treatments.


Asunto(s)
Apoptosis/efectos de los fármacos , Bioensayo , Indicadores y Reactivos/química , Necrosis/inducido químicamente , Oxazinas/química , Xantenos/química , Biomarcadores/metabolismo , Caspasa 3/genética , Caspasa 3/metabolismo , Caspasa 7/genética , Caspasa 7/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Dactinomicina/farmacología , Relación Dosis-Respuesta a Droga , Epidermis , Expresión Génica , Humanos , Peróxido de Hidrógeno/farmacología , Indoles/farmacología , Luz , Necrosis/metabolismo , Necrosis/patología , Triazoles/farmacología
10.
Nat Mater ; 15(1): 85-91, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26436340

RESUMEN

Controlling the alignment of the emitting molecules used as dopants in organic light-emitting diodes is an effective strategy to improve the outcoupling efficiency of these devices. To explore the mechanism behind the orientation of dopants in films of organic host materials, we synthesized a coumarin-based ligand that was cyclometalated onto an iridium core to form three phosphorescent heteroleptic molecules, (bppo)2Ir(acac), (bppo)2Ir(ppy) and (ppy)2Ir(bppo) (bppo represents benzopyranopyridinone, ppy represents 2-phenylpyridinate, and acac represents acetylacetonate). Each emitter was doped into a 4,4'-bis(N-carbazolyl)-1,1'-biphenyl host layer, and the resultant orientation of their transition dipole moment vectors was measured by angle-dependent p-polarized photoluminescent emission spectroscopy. In solid films, (bppo)2Ir(acac) is found to have a largely horizontal transition dipole vector orientation relative to the substrate, whereas (ppy)2Ir(bppo) and (bppo)2Ir(ppy) are isotropic. We propose that the inherent asymmetry at the surface of the growing film promotes dopant alignment in these otherwise amorphous films. Modelling the net orientation of the transition dipole moments of these materials yields general design rules for further improving horizontal orientation.

11.
J Clin Ultrasound ; 45(7): 400-407, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28251661

RESUMEN

BACKGROUND: We aimed to analyze the benefits of adding ultrasound (US) guidance to the standard fluoroscopically assisted percutaneous transhepatic biliary drainage (F-PTBD). We also performed a systematic literature review of success and complication rates of US-PTBD in a wide field of indications. METHODS: We evaluated a total of 81 US-PTBDs carried out in our institution, 74% of which were part of the management of malignancy. In addition, we compared our results with those of a total of 5,272 procedures (3,779 F-PTBD and 1,493 US-PTBD) reported in the literature. RESULTS: US-PTBD was technically successful in 94% of attempts with a mean of 2.2 needle passes. Procedural success was achieved in 86% of cases. There were no procedure-related deaths or severe complications. Minor complications were catheter dislodgement (15%) as well as one case each of a porto-biliary fistula, hematoma, and biloma. A systematic review of the literature also showed that US-PTBD has a similar technical success rate to F-PTBD but lower median rates of severe early complications (0% versus 8%) and procedural death (0% versus 1%). CONCLUSIONS: Given our results and our review of the literature, US-PTBD is as effective as F-PTBD and has significantly lower complication rates. US-PTBD should be preferred to F-PTBD. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:400-407, 2017.


Asunto(s)
Enfermedades de los Conductos Biliares/diagnóstico por imagen , Enfermedades de los Conductos Biliares/terapia , Drenaje/métodos , Ultrasonografía Intervencional/métodos , Anciano , Conductos Biliares/diagnóstico por imagen , Femenino , Fluoroscopía , Humanos , Masculino , Estudios Retrospectivos
12.
Int J Mol Sci ; 17(12)2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27916938

RESUMEN

MicroRNAs (miRNAs) are master regulators of drug resistance and have been previously proposed as potential biomarkers for the prediction of therapeutic response in colorectal cancer (CRC). Sorafenib, a multi-kinase inhibitor which has been approved for the treatment of liver, renal and thyroid cancer, is currently being studied as a monotherapy in selected molecular subtypes or in combination with other drugs in metastatic CRC. In this study, we explored sorafenib-induced cellular effects in Kirsten rat sarcoma viral oncogene homolog olog (KRAS) wild-type and KRAS-mutated CRC cell lines (Caco-2 and HRT-18), and finally profiled expression changes of specific miRNAs within the miRNome (>1000 human miRNAs) after exposure to sorafenib. Overall, sorafenib induced a time- and dose-dependent growth-inhibitory effect through S-phase cell cycle arrest in KRAS wild-type and KRAS-mutated CRC cells. In HRT-18 cells, two human miRNAs (hsa-miR-597 and hsa-miR-720) and two small RNAs (SNORD 13 and hsa-miR-3182) were identified as specifically sorafenib-induced. In Caco-2 cells, nine human miRNAs (hsa-miR-3142, hsa-miR-20a, hsa-miR-4301, hsa-miR-1290, hsa-miR-4286, hsa-miR-3182, hsa-miR-3142, hsa-miR-1246 and hsa-miR-720) were identified to be differentially regulated post sorafenib treatment. In conclusion, we confirmed sorafenib as a potential anti-neoplastic treatment strategy for CRC cells by demonstrating a growth-inhibitory and cell cycle-arresting effect of this drug. Changes in the miRNome indicate that some specific miRNAs might be relevant as indicators for sorafenib response, drug resistance and potential targets for combinatorial miRNA-based drug strategies.


Asunto(s)
Neoplasias Colorrectales/tratamiento farmacológico , MicroARNs/biosíntesis , Niacinamida/análogos & derivados , Compuestos de Fenilurea/administración & dosificación , Animales , Células CACO-2 , Puntos de Control del Ciclo Celular/efectos de los fármacos , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/genética , Mutación , Niacinamida/administración & dosificación , Proteínas Proto-Oncogénicas p21(ras)/genética , Sorafenib
13.
Int J Mol Sci ; 17(12)2016 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-27941621

RESUMEN

Extensive stromal interaction is one reason for the dismal outcome of biliary tract cancer (BTC) patients. Epithelial to mesenchymal transition (EMT) is involved in tumor invasion and metastasis and is partly regulated by microRNAs (miRs). This study explores the expression of anti-EMT miR200 family (miR141, -200a/b/c, -429) and miR205 as well as the EMT-related proteins E-cadherin and vimentin in a panel of BTC cell lines and clinical specimens by quantitative real-time polymerase chain reaction, Western blot and immunohistochemistry, respectively. MicroRNA expression was correlated to (i) the expression patterns of E-cadherin and vimentin; (ii) clinicopathological characteristics; and (iii) survival data. MicroRNA-200 family and miR205 were expressed in all BTC cells and clinical specimens. E-cadherin and vimentin showed a mutually exclusive expression pattern in both, in vitro and in vivo. Expression of miR200 family members positively correlated with E-cadherin and negatively with vimentin expression in BTC cells and specimens. High expression of miR200 family members (but not miR205) and E-cadherin was associated with longer survival, while low miR200 family and high vimentin expression was a predictor of unfavorable survival. Overall, the current study demonstrates the relevance of the miR200 family in EMT of BTC tumors and suggests these miRs as predictors for positive outcome.


Asunto(s)
Neoplasias del Sistema Biliar/genética , Neoplasias del Sistema Biliar/patología , Transición Epitelial-Mesenquimal/genética , MicroARNs/genética , Línea Celular Tumoral , Transición Epitelial-Mesenquimal/fisiología , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Regulación Neoplásica de la Expresión Génica/fisiología , Humanos , ARN Mensajero/genética
14.
BMC Complement Altern Med ; 15: 194, 2015 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-26100134

RESUMEN

BACKGROUND: The green tea catechin epigallocatechin gallate (EGCG) was shown to effectively inhibit tumor growth in various types of cancer including biliary tract cancer (BTC). For most BTC patients only palliative therapy is possible, leading to a median survival of about one year. Chemoresistance is a major problem that contributes to the high mortality rates of BTC. The aim of this study was to investigate the cytotoxic effect of EGCG alone or in combination with cisplatin on eight BTC cell lines and to investigate the cellular anti-cancer mechanisms of EGCG. METHODS: The effect of EGCG treatment alone or in combination with the standard chemotherapeutic cisplatin on cell viability was analyzed in eight BTC cell lines. Additionally, we analyzed the effects of EGCG on caspase activity, cell cycle distribution and gene expression in the BTC cell line TFK-1. RESULTS: EGCG significantly reduced cell viability in all eight BTC cell lines (p < 0.05 or p < 0.01, respectively, for most cell lines and EGCG concentrations > 5 µM). Combined EGCG and cisplatin treatment showed a synergistic cytotoxic effect in five cell lines and an antagonistic effect in two cell lines. Furthermore, EGCG reduced the mRNA levels of various cell cycle-related genes, while increasing the expression of the cell cycle inhibitor p21 and the apoptosis-related death receptor 5 (p < 0.05). This observation was accompanied by an increase in caspase activity and cells in the sub-G1 phase of the cell cycle, indicating induction of apoptosis. EGCG also induced a down-regulation of expression of stem cell-related genes and genes that are associated with an aggressive clinical character of the tumor, such as cd133 and abcg2. CONCLUSIONS: EGCG shows various anti-cancer effects in BTC cell lines and might therefore be a potential anticancer drug for future studies in BTC. Additionally, EGCG displays a synergistic cytotoxic effect with cisplatin in most tested BTC cell lines. Graphical abstract Summary illustration.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias del Sistema Biliar , Catequina/análogos & derivados , Puntos de Control del Ciclo Celular/efectos de los fármacos , Cisplatino/farmacología , Apoptosis/efectos de los fármacos , Catequina/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Sinergismo Farmacológico , Humanos
15.
Int J Mol Sci ; 16(11): 26619-28, 2015 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-26561801

RESUMEN

Hilar cholangiocarcinoma (CC) is non-resectable in the majority of patients often due to intrahepatic extension along bile duct branches/segments, and even after complete resection (R0) recurrence can be as high as 70%. Photodynamic therapy (PDT) is an established palliative local tumor ablative treatment for non-resectable hilar CC. We report the long-term outcome of curative resection (R0) performed after neoadjuvant PDT for downsizing of tumor margins in seven patients (median age 59 years) with initially non-resectable hilar CC. Photofrin(®) was injected intravenously 24-48 h before laser light irradiation of the tumor stenoses and the adjacent bile duct segments. Major resective surgery was done with curative intention six weeks after PDT. All seven patients had been curatively (R0) resected and there were no undue early or late complications for the neoadjuvant PDT and surgery. Six of seven patients died from tumor recurrence at a median of 3.2 years after resection, the five-year survival rate was 43%. These results are comparable with published data for patients resected R0 without pre-treatment, indicating that neoadjuvant PDT is feasible and could improve overall survival of patients considered non-curatively resectable because of initial tumor extension in bile duct branches/segments--however, this concept needs to be validated in a larger trial.


Asunto(s)
Neoplasias de los Conductos Biliares/tratamiento farmacológico , Éter de Dihematoporfirina/uso terapéutico , Tumor de Klatskin/tratamiento farmacológico , Terapia Neoadyuvante/métodos , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Adulto , Anciano , Neoplasias de los Conductos Biliares/mortalidad , Neoplasias de los Conductos Biliares/patología , Neoplasias de los Conductos Biliares/cirugía , Conductos Biliares Intrahepáticos/efectos de los fármacos , Conductos Biliares Intrahepáticos/patología , Conductos Biliares Intrahepáticos/cirugía , Femenino , Humanos , Inyecciones Intravenosas , Tumor de Klatskin/mortalidad , Tumor de Klatskin/patología , Tumor de Klatskin/cirugía , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Cuidados Paliativos/métodos , Proyectos Piloto , Recurrencia , Análisis de Supervivencia
16.
Mol Cell Biochem ; 396(1-2): 257-68, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25064451

RESUMEN

Hedgehog (Hh) signalling contributes to carcinogenesis and represents a valid druggable target in human cancers, possibly also in biliary tract cancer (BTC). We analysed the expression of Hh components in BTC using eight heterogeneously differentiated cell lines, xenograft tumours and a human tissue microarray. The dose-, time- and cell line-dependent effects of two Hh inhibitors (cyclopamine and Gant-61) were analysed in vitro for survival, apoptosis, cell cycle distribution and possible synergism with conventional chemotherapeutic agents. In human BTC samples, the sonic Hh ligand and the Gli1 transcription factor showed increased expression in tumours compared to normal adjacent tissue and were significantly associated with high tumour grade and positive lymph node status. In BTC cell lines, we could confirm the Hh component expression at varying extent within the employed cell lines in vitro and in vivo indicating non-canonical signalling. Both Hh inhibitors showed dose-dependent cytotoxicity above 5 µM with a stronger effect for Gant-61 inducing apoptosis whereas cyclopamine rather inhibited proliferation. Cytotoxicity was associated with low cytokeratin expression and higher mesenchymal marker expression such as vimentin. Additionally, drug combinations of Gant-61 with conventional chemotherapy (cisplatin) exerted synergistic effects. In conclusion, Hh pathway is significantly activated in human BTC tissue compared to normal adjacent tissue. The current data demonstrate for the first time an effective anticancer activity of especially Gant-61 in BTC and suggest second generation Hh pathway inhibitors as a potential novel treatment strategy in BTC.


Asunto(s)
Neoplasias del Sistema Biliar/tratamiento farmacológico , Neoplasias del Sistema Biliar/metabolismo , Proteínas Hedgehog/metabolismo , Piridinas/farmacología , Pirimidinas/farmacología , Animales , Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Neoplasias del Sistema Biliar/patología , Línea Celular Tumoral/efectos de los fármacos , Cisplatino/administración & dosificación , Relación Dosis-Respuesta a Droga , Proteínas Hedgehog/antagonistas & inhibidores , Proteínas Hedgehog/genética , Humanos , Ratones Mutantes , Terapia Molecular Dirigida/métodos , Piridinas/administración & dosificación , Pirimidinas/administración & dosificación , Transducción de Señal/efectos de los fármacos , Análisis de Matrices Tisulares , Factores de Transcripción/metabolismo , Alcaloides de Veratrum/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto , Proteína con Dedos de Zinc GLI1
17.
Int J Mol Sci ; 15(11): 20134-57, 2014 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-25380521

RESUMEN

Photodynamic therapy (PDT) is a palliative treatment option for unresectable hilar biliary tract cancer (BTC) showing a considerable benefit for survival and quality of life with few side effects. Currently, factors determining the cellular response of BTC cells towards PDT are unknown. Due to their multifaceted nature, microRNAs (miRs) are a promising analyte to investigate the cellular mechanisms following PDT. For two photosensitizers, Photofrin® and Foscan®, the phototoxicity was investigated in eight BTC cell lines. Each cell line (untreated) was profiled for expression of n=754 miRs using TaqMan® Array Human MicroRNA Cards. Statistical analysis and bioinformatic tools were used to identify miRs associated with PDT efficiency and their putative targets, respectively. Twenty miRs correlated significantly with either high or low PDT efficiency. PDT was particularly effective in cells with high levels of clustered miRs 25-93*-106b and (in case of miR-106b) a phenotype characterized by high expression of the mesenchymal marker vimentin and high proliferation (cyclinD1 and Ki67 expression). Insensitivity towards PDT was associated with high miR-200 family expression and (for miR-cluster 200a/b-429) expression of differentiation markers Ck19 and Ck8/18. Predicted and validated downstream targets indicate plausible involvement of miRs 20a*, 25, 93*, 130a, 141, 200a, 200c and 203 in response mechanisms to PDT, suggesting that targeting these miRs could improve susceptibility to PDT in insensitive cell lines. Taken together, the miRNome pattern may provide a novel tool for predicting the efficiency of PDT and-following appropriate functional verification-may subsequently allow for optimization of the PDT protocol.


Asunto(s)
Neoplasias del Sistema Biliar/tratamiento farmacológico , Neoplasias del Sistema Biliar/genética , MicroARNs/genética , Fotoquimioterapia , Neoplasias del Sistema Biliar/patología , Biomarcadores de Tumor/metabolismo , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Biología Computacional , Simulación por Computador , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Ontología de Genes , Glutatión/metabolismo , Humanos , Mesoporfirinas/farmacología , MicroARNs/metabolismo , Resultado del Tratamiento
18.
PLoS One ; 19(4): e0302050, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38603713

RESUMEN

INTRODUCTION: Biliary tract cancer (BTC) is a lethal disease with a bad overall survivability, partly arising from inadequate therapeutic alternatives, detection at a belated stage, and a resistance to common therapeutic approaches. Ferroptosis is a form of programmed cell death that depends on reactive oxygen species (ROS) and iron, causing excessive peroxidation of polyunsaturated fatty acids (PUFAs). Therefore, the objective of this investigation is, whether ferroptosis can be induced in BTC in vitro and whether this induction is dependent on specific molecular markers. METHODS: The study conducted resazurin assay and IC25/50 calculation to explore the possible cytotoxic outcomes of different classes of ferroptosis-inducing substances (FINs) on a comprehensive in vitro model of 11 BTC cell lines. Combinatory treatments with different cell death inhibitors were performed to evaluate the magnitude of ferroptosis induction. To ascertain whether ferroptotic cell death occurred, liperfluo and iron assay kits were employed to evaluate lipid ROS and intracellular iron abundance. Potential biomarkers of ferroptosis sensitivity were then assessed via western blot analysis, a rtPCR panel and functional assay kits. RESULTS: The study found that different FINs reduced cell viability in a cell line-dependent manner. In addition, we measured increased lipid ROS and intracellular Fe2+ levels upon exposure to FINs in BTC cells. Combining FINs with inhibitors of ferroptosis, necroptosis or apoptosis suggests the occurrence of ferroptotic events in BTC cell lines CCC-5, HuH-28 and KKU-055. Furthermore, we found that BTC cells display a heterogeneous profile regarding different molecular genes/markers of ferroptosis. Subsequent analysis revealed that sensitivity of BTC cells towards IKE and RSL3 positively correlated with CD71 and SLC7A11 protein expression. CONCLUSION: Our results demonstrate that induction of ferroptosis is a promising approach to inhibit BTC cell growth and that the sensitivity of BTC cells towards ferroptosis induction might be dependent on molecular markers such as CD71 and SLC7A11.


Asunto(s)
Neoplasias del Sistema Biliar , Ferroptosis , Humanos , Especies Reactivas de Oxígeno/metabolismo , Hierro/metabolismo , Lípidos , Sistema de Transporte de Aminoácidos y+/genética
19.
Expert Rev Endocrinol Metab ; 18(2): 143-154, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36872882

RESUMEN

INTRODUCTION: The pathogenic role of deregulated histone (de-)acetylation by histone deacetyles (HDACs) has been demonstrated in several human cancers. While some HDAC inhibitors (HDACi) have been approved for individual entities, for endocrine tumors such translation into clinical practice has not yet been achieved. AREAS COVERED: Relevant results identified by structured searches in PubMed as well as in reference lists are summarized in a narrative review to discuss the current knowledge of HDAC involvement and their therapeutic relevance in endocrine tumors. For thyroid, neuroendocrine, and adrenal tumors, various oncogenic mechanisms of HDAC deregulation and effects of HDAC inhibitors (HDACi) have been identified in preclinical studies including direct cancer cell toxicity and modification of differentiation status. EXPERT OPINION: Based on positive pre-clinical results, the research on HDAC (inhibition) in the various endocrine tumors should be intensified - yet, it needs to be considered that i) HDACs' oncogenic actions might constitute only a part of epigenetic mechanisms driving cancer, ii) individual HDAC has different roles in different endocrine tumor entities, iii) inhibition of HDACs might be especially attractive in combination with conventional or other targeted therapies, and iv) new HDAC-inhibiting drugs with improved specificity or functionally modified HDACi might further improve their efficacy.


Asunto(s)
Histonas , Neoplasias , Humanos , Histonas/metabolismo , Histonas/uso terapéutico , Inhibidores de Histona Desacetilasas/farmacología , Inhibidores de Histona Desacetilasas/uso terapéutico , Histona Desacetilasas/genética , Histona Desacetilasas/metabolismo , Histona Desacetilasas/uso terapéutico , Epigénesis Genética
20.
Front Neurosci ; 17: 1223262, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37609449

RESUMEN

The potential low-energy feature of the spiking neural network (SNN) engages the attention of the AI community. Only CPU-involved SNN processing inevitably results in an inherently long temporal span in the cases of large models and massive datasets. This study introduces the MAC array, a parallel architecture on each processing element (PE) of SpiNNaker 2, into the computational process of SNN inference. Based on the work of single-core optimization algorithms, we investigate the parallel acceleration algorithms for collaborating with multi-core MAC arrays. The proposed Echelon Reorder model information densification algorithm, along with the adapted multi-core two-stage splitting and authorization deployment strategies, achieves efficient spatio-temporal load balancing and optimization performance. We evaluate the performance by benchmarking a wide range of constructed SNN models to research on the influence degree of different factors. We also benchmark with two actual SNN models (the gesture recognition model of the real-world application and balanced random cortex-like network from neuroscience) on the neuromorphic multi-core hardware SpiNNaker 2. The echelon optimization algorithm with mixed processors realizes 74.28% and 85.78% memory footprint of the original MAC calculation on these two models, respectively. The execution time of echelon algorithms using only MAC or mixed processors accounts for ≤ 24.56% of the serial ARM baseline. Accelerating SNN inference with algorithms in this study is essentially the general sparse matrix-matrix multiplication (SpGEMM) problem. This article explicitly expands the application field of the SpGEMM issue to SNN, developing novel SpGEMM optimization algorithms fitting the SNN feature and MAC array.

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