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1.
J Invest Dermatol ; 142(9): 2499-2507.e6, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35189148

RESUMEN

A subset of dual-specificity phosphatases is a major negative regulator of MAPKs, and their involvement in tumorigenesis remains controversial. Among them, DUSP4 is reported to preferentially dephosphorylate extracellular signal‒regulated kinase (ERK) 1/2 and c-Jun N-terminal kinase over p38. In this study, we aimed to identify a possible role of DUSP4 in melanoma genesis. An examination of large-scale public data on gene expression and dependency revealed a considerably high DUSP4 expression and dependency of the melanoma cell lines compared with those of other tumor cell lines, which was not apparent for the other 24 dual-specificity phosphatases genes encoded in the human genome. Using two melanoma lines, we confirmed that DUSP4 depletion impaired cell growth without notably inducing apoptosis. Interestingly, immunoblotting and kinase translocation reporter data revealed that DUSP4 depletion induces a decrease in ERK1/2 phosphorylation but barely affects c-Jun N-terminal kinase phosphorylation, suggesting that neither ERK nor c-Jun N-terminal kinase is a direct target of DUSP4 in our experimental setting. Notably, DUSP4 depletion led to an increase in DUSP6 level, possibly through a post-transcriptional process, and DUSP6 knockout almost eliminated the DUSP4-depletion effect on cell growth and ERK activity. Our findings suggest that DUSP4 plays a role in maintaining a high ERK1/2 activity by negatively regulating DUSP6 and thus contributes to the survival and growth of melanoma cells.


Asunto(s)
Fosfatasa 6 de Especificidad Dual , Fosfatasas de Especificidad Dual , Sistema de Señalización de MAP Quinasas , Melanoma , Fosfatasa 6 de Especificidad Dual/genética , Fosfatasa 6 de Especificidad Dual/metabolismo , Fosfatasas de Especificidad Dual/genética , Fosfatasas de Especificidad Dual/metabolismo , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Melanoma/genética , Fosfatasas de la Proteína Quinasa Activada por Mitógenos/genética , Fosfatasas de la Proteína Quinasa Activada por Mitógenos/metabolismo , Fosforilación , Regulación hacia Arriba
2.
Anticancer Drugs ; 30(5): 451-457, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30920401

RESUMEN

Although vemurafenib has been shown to improve the overall survival of patients with metastatic melanoma harboring the BRAF V600E mutation, its efficacy is often hampered by drug resistance acquired within a relatively short period through several distinct mechanisms. In the present study, we investigated the effect of fluvastatin as a possible strategy to overcome such acquired resistance using a cultured cell line model. We established vemurafenib-resistant (VR) cells from three BRAF (V600E)-mutated melanoma lines (C32, HMY-1, and SK-MEL-28) and evaluated the mechanism of acquired resistance of VR cells by water-soluble tetrazolium salts assay, western blot, real-time quantitative PCR, and immunofluorescent microscopy. The efficacy of the combination of growth inhibitory effect of vemurafenib and fluvastatin on respective parental and VR cells were assessed by calculating combination index and western blot. IC50 values of three VR cells were ~5-100-fold higher than those for the respective parental cells. The VR cells derived from HMY-1 and SK-MEL-28 showed constitutive activation of AKT kinase, and the specific AKT inhibitor MK-2208 or the PI3K inhibitor wortmannin increased the cellular sensitivity to vemurafenib. Intriguingly, application of a statin-related drug, fluvastatin, also resulted in a synergistic increase of sensitivity to vemurafenib in the VR cells (combination index: 0.73-0.86) probably by alleviating constitutive AKT activation, whereas the same treatment did not notably alter the vemurafenib sensitivity of the parental cells. Our results suggest the possible usefulness of statin-related drugs for overcoming vemurafenib resistance acquired through constitutive activation of the PI3K-AKT axis.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Biomarcadores de Tumor/metabolismo , Proliferación Celular , Resistencia a Antineoplásicos/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Melanoma/tratamiento farmacológico , Aciltransferasas , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Apoptosis , Biomarcadores de Tumor/genética , Fluvastatina/administración & dosificación , Humanos , Melanoma/metabolismo , Melanoma/patología , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Células Tumorales Cultivadas , Vemurafenib/administración & dosificación , Proteínas Señalizadoras YAP
3.
PLoS One ; 14(2): e0212821, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30785962

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0209296.].

4.
PLoS One ; 13(12): e0209296, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30557316

RESUMEN

Cultured cells easily develop resistance to kinesin-5 inhibitors (K5Is) often by overexpressing a related motor protein, kinesin-12/KIF15, or by acquiring mutations in the N-terminal motor domain of kinesin-5/KIF11 itself. We aimed to identify novel mechanisms responsible for resistance to S-trityl L-cysteine (STLC), one of the K5Is, using human osteosarcoma cell lines. Among six lines examined, U-2OS and HOS survived chronic STLC treatment and gave rise to resistant cells with IC50s at least 10-fold higher than those of the respective parental lines. Depletion of KIF15 largely eliminated the acquired K5I resistance in both cases, consistent with the proposed notion that KIF15 is indispensable for it. In contrast to the KIF11-independent property of the cells derived from HOS, those derived from U-2OS still required KIF11 for their growth and, intriguingly, expressed a C-terminal truncated variant of KIF11 resulting from a frame shift mutation (S1017fs). All of the isolated clones harbored the same mutation, suggesting its clonal expansion in the cell population due to the growth advantage during chronic STLC treatment. Transgenic expression of KIF11S1017fs in the parental U-2OS cells, as well as in HeLa cells, conferred a moderate but reproducible STLC resistance, probably owing to STLC-resistant localization of the mutant KIF11 on mitotic spindle. Our observations indicate that both KIF15 and the C-terminal-truncated KIF11 contributes to the STLC resistance of the U-2OS derived cells.


Asunto(s)
Antimitóticos/farmacología , Cisteína/análogos & derivados , Resistencia a Medicamentos/fisiología , Cinesinas/antagonistas & inhibidores , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cisteína/farmacología , Resistencia a Medicamentos/genética , Dineínas/metabolismo , Expresión Génica , Técnicas de Silenciamiento del Gen , Células HeLa , Humanos , Cinesinas/genética , Cinesinas/metabolismo , Mutación , Membrana Nuclear/efectos de los fármacos , Membrana Nuclear/metabolismo , Huso Acromático/efectos de los fármacos , Huso Acromático/metabolismo
5.
Oncotarget ; 9(17): 13287-13300, 2018 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-29568357

RESUMEN

A prognostic association between the novel chaperone protein-L-isoaspartate (D-aspartate) O-methyltransferase (PIMT) and lung adenocarcinoma has recently been reported. Here, we evaluated the functional roles of PIMT in the progression of lung adenocarcinoma. PIMT expression was detectable in 6 lung adenocarcinoma cell lines: A549, H441, H460, H1650, Calu 1, and Calu 6 cell lines. In A549 and H441 cells, knockdown by PIMT using silencing RNA of PIMT (si-PIMT) and/or small hairpin-RNA (sh-PIMT) induced a decrease in the expression of E-cadherin with an increase in vimentin expression, indicating that the epithelial to mesenchymal transition (EMT) was induced. Cell mobility, including migration and invasion capability, was increased in sh-PIMT A549 stable and si-PIMT H441 cells compared to in control cells. Endoplasmic reticulum (ER) stress, such as Thapsigargin (Tg) stress and hypoxia, induced EMT in A549 cells but not in other cell types, with an increase in GRP78 expression, whereas overexpression of PIMT reduced the EMT and cell invasion under stress conditions. The expression of hypoxia inducible factor-1 alpha (HIF1α) and Twist increased in sh-PIMT A549 and si-PIMT H441 cells, and Tg stress increased HIF1α expression levels in A549 cells in a dose-dependent manner. Moreover, LW6, an HIF1α inhibitor, reduced EMT, cancer invasion, and the levels of Twist in sh-PIMT A549 cells. Our results indicate that deficiency of supplemental PIMT expression under ER stress facilitates EMT and cell invasion in some cell types of lung adenocarcinoma.

6.
Oncol Lett ; 15(2): 2393-2400, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29434949

RESUMEN

NAD(P)H quinone oxidoreductase 1 (NQO1)-dependent antitumor drugs such as ß-lapachone (ß-lap) are attractive candidates for cancer chemotherapy because several tumors exhibit higher expression of NQO1 than adjacent tissues. Although the association between NQO1 and ß-lap has been elucidated, the effects of a NQO1-inducer and ß-lap used in combination remain to be clarified. It has previously been reported that melanoma cell lines have detectable levels of NQO1 expression and are sensitive to NQO1-dependent drugs such as 17-allylamino-17-demethoxygeldanamycin. The present study was conducted to investigate the involvement of NQO1 in ß-lap-mediated toxicity and the utility of combination treatment with a NQO1-inducer and ß-lap in malignant melanoma cell lines. Decreased expression or inhibition of NQO1 caused these cell lines to become less sensitive to ß-lap, indicating a requirement of NQO1 activity for ß-lap-mediated toxicity. Of note was that carnosic acid (CA), a compound extracted from rosemary, was able to induce further expression of NQO1 through NF-E2 related factor 2 (NRF2) stabilization, thus significantly enhancing the cytotoxicity of ß-lap in all of the melanoma cell lines tested. Taken together, the data presented in the current study indicated that the NRF2-NQO1 axis may have potential value as a therapeutic target in malignant melanoma to improve the rate of clinical response to NQO1-dependent antitumor drugs.

7.
Oncotarget ; 8(55): 93729-93740, 2017 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-29212185

RESUMEN

Most malignant mesotheliomas (MPMs) frequently show activated forms of Yes-associated protein 1 (YAP1) and transcriptional co-activator with PDZ-binding motif (TAZ), which transcriptionally regulates the receptor for hyaluronic acid-mediated motility (RHAMM). As RHAMM is involved in cell migration and invasion in various tumors, we speculated that hyaluronic acid (HA) in pleural fluid might affect the progression of mesothelioma by stimulating cell migration and invasion through RHAMM. The level of RHAMM expression was decreased by YAP1/TAZ knockdown, and conversely increased by forced expression of the active form of YAP1, suggesting that RHAMM was regulated by YAP1/TAZ in MPM cells. Cell migration and invasion were also decreased by YAP1/TAZ or RHAMM knockdown. Notably, HA treatment increased cell motility and invasion, and this was abolished by RHAMM knockdown, suggesting that HA may augment local progression of MPM cells via RHAMM. Furthermore, treatment with fluvastatin, which regulates RHAMM transcription by modulating YAP1/TAZ activity, decreased the motility and invasion of MPM cells. Collectively, these data suggest that HA is an "unfavorable" factor because it promotes malignancy in mesothelioma and that the YAP1/TAZ-RHAMM axis may have potential value as a therapeutic target for inhibition of disease progression in MPM.

8.
PLoS One ; 12(10): e0186260, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29023497

RESUMEN

Transcription factors PAX9 and MSX1 play crucial roles in the development of permanent teeth at the bud stage, and their loss-of-function variants have been associated with congenital tooth agenesis. We sequenced the coding regions of the PAX9 and MSX1 genes from nine patients with non-syndromic tooth agenesis, and identified a missense mutation, P20L, of PAX9 in a single familial case involving three patients in two generations. Identical mutation was previously reported by other authors, but has not been characterized in detail. The mutation was located in a highly conserved N-terminal subdomain of the paired domain and co-segregated as a heterozygote with tooth agenesis. The patients showed defects primarily in the first and second molars, which is typical for cases attributable to PAX9 mutation. Luciferase reporter assay using the 2.3-kb promoter region of BMP4 and electrophoretic mobility shift assay using the CD19-2(A-ins) sequence revealed that P20L substitution eliminated most of the transactivation activity and specific DNA binding activity of PAX9 under the experimental conditions we employed, while some residual activity of the mutant was evident in the former assay. The hypomorphic nature of the variant may explain the relatively mild phenotype in this case, as compared with other PAX9 pathogenic variants such as R26W.


Asunto(s)
Anodoncia/genética , Factor de Transcripción PAX9/genética , Adolescente , Adulto , Animales , Proteína Morfogenética Ósea 4/genética , Células COS , Chlorocebus aethiops , Ensayo de Cambio de Movilidad Electroforética , Femenino , Humanos , Factor de Transcripción MSX1/genética , Masculino , Persona de Mediana Edad , Modelos Moleculares , Factor de Transcripción PAX9/química , Factor de Transcripción PAX9/fisiología , Linaje , Estructura Terciaria de Proteína
9.
Oncol Lett ; 14(1): 903-908, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28693250

RESUMEN

Pancreatic ductal adenocarcinoma (PDA) is an aggressive malignant disease that is resistant to various chemotherapeutic agents and commonly relapses. Efficient elimination of metastasized PDA is critical for a positive post-surgical treatment outcome. The present study analyzed the effect of the B-cell lymphoma-2 (Bcl-2)/B-cell lymphoma extra-large (Bcl-xL) inhibitor, ABT-737, on paclitaxel-induced PDA cell death. A total of 8 PDA cell lines were subjected to immunoblotting to compare the expression of Bcl-2/Bcl-xL and other factors associated with taxane resistance, including myeloid cell leukemia 1 and ßIII-tubulin (TUBB3). The viability of PDA cells was analyzed following treatment with paclitaxel alone or a combination treatment with ABT-737 and paclitaxel. Treatment with the ABT-737/paclitaxel combination induced PDA cell death at a lower concentration of paclitaxel compared with paclitaxel alone. In addition, the viable cell population at the saturation point of paclitaxel was also decreased by co-treatment with ABT-737. ABT-737 lowered the half maximal inhibitory concentration (IC50) by >2-fold in PDA cells with high Bcl-2/Bcl-xL expression, but not in PDA cells with low Bcl-2/Bcl-xL expression and high TUBB3 expression. Knockdown of Bcl-xL lowered the IC50 of paclitaxel, but knockdown of TUBB3 did not. ABT-737 sensitized PDA to paclitaxel-induced cell death, and Bcl-xL expression was a key determinant of its sensitivity. ABT-737 is potential candidate for combination chemotherapy of PDA with high Bcl-xL expression levels.

10.
Anticancer Res ; 37(4): 1793-1797, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28373443

RESUMEN

BACKGROUND: Breast tumor heterogeneity leads to phenotypic diversity, such as tumor-initiating and metastatic properties and drug sensitivity. MATERIALS AND METHODS: We found that a self-floating cell (SFC) culture enriches a drug-resistant subpopulation in a HER2-positive breast cancer cell line. SFCs were analyzed for cancer stem cell markers, gene expression profiles, and sensitivity for anticancer drugs. RESULTS: SFCs expressed cancer stem cell markers, such as aldehyde dehydrogenase (ALDH) activity and elevated HER2 autophosphorylation. Gene expression profiles of SFCs showed a dramatic difference compared to those of parental or forced floating cells. SFCs also expressed CD133, a marker of drug resistance, and resisted cytotoxic drugs by drug efflux transporters. In contrast, HER2 kinase inhibitors efficiently reduced SFC viability. CONCLUSION: SFCs enrich drug-resistant subpopulations even in vitro and might reflect the highly plastic nature of breast cancer cells even in vitro.


Asunto(s)
Adenocarcinoma Papilar/patología , Adenocarcinoma/patología , Neoplasias de la Mama/patología , Técnicas de Cultivo de Célula/métodos , Células Madre Neoplásicas/patología , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma Papilar/tratamiento farmacológico , Adenocarcinoma Papilar/genética , Adenocarcinoma Papilar/metabolismo , Aldehído Deshidrogenasa/genética , Aldehído Deshidrogenasa/metabolismo , Antineoplásicos/farmacología , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Western Blotting , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Femenino , Citometría de Flujo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Técnicas In Vitro , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Fenotipo , Células Tumorales Cultivadas
11.
Rinsho Ketsueki ; 58(2): 126-131, 2017.
Artículo en Japonés | MEDLINE | ID: mdl-28321089

RESUMEN

Case 1: A 78-year-old woman was diagnosed with H. pylori positive gastritis at a previous hospital in April 2012 and received 3rd-line H. pylori eradication therapy, which ended in failure. She was referred to our department due to oral hemorrhage, petechiae involving all four extremities, and thrombocytopenia in January 2016. She was hospitalized with a diagnosis of ITP and received inpatient treatment. While receiving outpatient prednisolone (PSL) treatment, we administered 4th-line eradication therapy in March. Her platelet levels have since returned to normal, and PSL treatment has been discontinued. She is currently followed without treatment. Case 2: A 65-year-old woman was diagnosed with ITP at a previous hospital in June 2013 and received 2nd-line eradication therapy, which ended in failure. Thereafter, PSL treatment was continued but she was later referred to our department in March 2016. Since 3rd-line eradication therapy was successful, her platelet count normalized and PSL treatment has been discontinued. She is currently followed without treatment. Based on our observations in these two cases, third-line H. pylori eradication therapy is potentially effective in ITP patients.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/aislamiento & purificación , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Trombocitopenia/tratamiento farmacológico , Anciano , Femenino , Infecciones por Helicobacter/diagnóstico , Helicobacter pylori/efectos de los fármacos , Humanos , Púrpura Trombocitopénica Idiopática/complicaciones , Púrpura Trombocitopénica Idiopática/diagnóstico , Trombocitopenia/complicaciones , Resultado del Tratamiento
12.
Cell Cycle ; 15(23): 3268-3277, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27764550

RESUMEN

Spindle poisons elicit various cellular responses following metaphase arrest, but how they relate to long-term clonogenicity has remained unclear. We prepared several HeLa lines in which the canonical apoptosis pathway was attenuated, and compared their acute responses to paclitaxel, as well as long-term fate, with the parental line. Three-nanomolar paclitaxel induced brief metaphase arrest (<5 h) often followed by aberrant mitosis, and about 90% of the cells of each line had lost their clonogenicity after 48 h of the treatment. A combination of the same concentration of paclitaxel with the kinesin-5 inhibitor, S-trityl-L-cysteine (STLC), at 1 µM led to much longer arrest (∼20 h) and predominance of subsequent line-specific responses: mitochondrial outer membrane permeabilization (MOMP) in the apoptosis-prone line, or mitotic slippage without obvious MOMP in the apoptosis-reluctant lines. In spite of this, combination with STLC did not lead to a marked difference in clonogenicity between the apoptosis-prone and -reluctant lines, and intriguingly resulted in slightly better clonogenicity than that of cells treated with 3 nM paclitaxel alone. This indicates that changes in the short-term response within 3 possible scenarios - acute MOMP, mitotic slippage or aberrant mitosis - has only a weak impact on clonogenicity. Our results suggest that once cells have committed to slippage or aberrant mitosis they eventually undergo proliferative death irrespective of canonical apoptosis or p53 function. Consistent with this, cells with irregular DNA contents originating from mitotic slippage or aberrant mitosis were mostly eliminated from the population within several rounds of division after the drug treatment.


Asunto(s)
Apoptosis/efectos de los fármacos , Mitosis/efectos de los fármacos , Paclitaxel/farmacología , Proteína p53 Supresora de Tumor/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Clonales , Cisteína/análogos & derivados , Cisteína/farmacología , ADN/metabolismo , Genes Reporteros , Células HeLa , Humanos , Cinesinas/antagonistas & inhibidores , Cinesinas/metabolismo , Melanoma/patología , Membranas Mitocondriales/efectos de los fármacos , Membranas Mitocondriales/metabolismo , Permeabilidad , Fenotipo , Reproducibilidad de los Resultados , Imagen de Lapso de Tiempo
13.
PLoS One ; 11(4): e0153181, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27045471

RESUMEN

The KEAP1-NRF2 pathway regulates cellular redox homeostasis by transcriptional induction of genes associated with antioxidant synthesis and detoxification in response to oxidative stress. Previously, we reported that KEAP1 mutation elicits constitutive NRF2 activation and resistance to cisplatin (CDDP) and dacarbazine (DTIC) in human melanomas. The present study was conducted to clarify whether an HSP90 inhibitor, 17-AAG, efficiently eliminates melanoma with KEAP1 mutation, as the NRF2 target gene, NQO1, is a key enzyme in 17-AAG bioactivation. In melanoma and non-small cell lung carcinoma cell lines with or without KEAP1 mutations, NQO1 expression and 17-AAG sensitivity are inversely correlated. NQO1 is highly expressed in normal melanocytes and in several melanoma cell lines despite the presence of wild-type KEAP1, and the NQO1 expression is dependent on NRF2 activation. Because either CDDP or DTIC produces reactive oxygen species that activate NRF2, we determined whether these agents would sensitize NQO1-low melanoma cells to 17-AAG. Synergistic cytotoxicity of the 17-AAG and CDDP combination was detected in four out of five NQO1-low cell lines, but not in the cell line with KEAP1 mutation. These data indicate that 17-AAG could be a potential chemotherapeutic agent for melanoma with KEAP1 mutation or NQO1 expression.


Asunto(s)
Benzoquinonas/farmacología , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Lactamas Macrocíclicas/farmacología , Melanoma/patología , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Cisplatino/farmacología , Sinergismo Farmacológico , Regulación de la Expresión Génica , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Proteína 1 Asociada A ECH Tipo Kelch , Neoplasias Pulmonares/patología , Melanocitos/enzimología , Melanoma/enzimología , Mutación , NAD(P)H Deshidrogenasa (Quinona)/genética , Transcripción Genética
14.
Pigment Cell Melanoma Res ; 29(3): 309-16, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26847926

RESUMEN

Rhododendrol (RD) is a potent tyrosinase inhibitor that is metabolized to RD-quinone by tyrosinase, which may underlie the cytotoxicity of RD and leukoderma of the skin that may result. We have examined how forced expression of the NAD(P)H quinone dehydrogenase, quinone 1 (NQO1), a major quinone-reducing enzyme in cytosol, affects the survival of RD-treated cells. We found that treatment of the mouse melanoma cell line B16BL6 or normal human melanocytes with carnosic acid, a transcriptional inducer of the NQO1 gene, notably suppressed the cell killing effect of RD. This effect was mostly abolished by ES936, a highly specific NQO1 inhibitor. Moreover, conditional overexpression of the human NQO1 transgene in B16BL6 led to an expression-dependent increase of cell survival after RD treatment. Our results suggest that NQO1 attenuates the cytotoxicity of RD and/or its metabolites.


Asunto(s)
Butanoles/farmacología , Citoprotección/efectos de los fármacos , Melaninas/biosíntesis , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Abietanos/farmacología , Animales , Apoptosis/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Modelos Animales de Enfermedad , Humanos , Ácidos Indolacéticos/farmacología , Melanocitos/efectos de los fármacos , Melanocitos/patología , Ratones , Transcripción Genética/efectos de los fármacos
15.
J Oral Sci ; 57(4): 313-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26666854

RESUMEN

We examined the role of Tie2 in regulating wound healing after tooth extraction. Wistar rats underwent maxillary incisor tooth extraction, and immunodetection techniques were used to determine Tie2 expression in the healing wound. The wound was initially filled with blood coagulum containing densely aggregated erythrocytes, leukocytes, fibrin, and endothelial progenitor cells, indicating that blood vessel formation started in the socket. Tie2 was detected on monocytic cell membranes. On day 3, fibroblastic cells proliferated in the coagulum, small vessels appeared by day 5, and new bone formed in the vessel-rich area. Robust woven bone trabeculae were present around vessels by day 7, and woven bone and osteoclast-like giant cells were present on day 10. Woven bone surrounded sinusoidal capillary-like vessels. Full-length (140-160 kDa) Tie2 was not detected at any time, although Tie2 fragments were present in the healing wound. N-terminus- and C-terminus-specific Tie2 antibodies detected 40-kDa and 60-kDa fragments or 70-kDa and 50-kDa fragments, respectively. The levels of these fragments decreased during the first 3 days and started to increase by day 5-10. The Tie2 extracellular domain initially inhibited angiogenesis, and its degradation relieved inhibition of new vessel formation. The onset of vessel formation in the wound may be induced by scattered endothelial progenitor cells.


Asunto(s)
Receptor TIE-2/metabolismo , Extracción Dental , Cicatrización de Heridas , Animales , Western Blotting , Desarrollo Óseo , Ratas , Ratas Wistar
16.
Cancer Sci ; 106(7): 848-56, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25891951

RESUMEN

Nucleus accumbens associated 1 (NACC1) is a cancer-associated BTB/POZ (pox virus and zinc finger/bric-a-brac tramtrack broad complex) gene, and is involved in several cellular functions in neurons, cancer and stem cells. Some of the BTB/POZ proteins associated with cancer biology are SUMOylated, which appears to play an important role in transcription regulation. We show that NACC1 is SUMOylated on a phylogenetically conserved lysine (K167) out of three consensus SUMOylation motif sites. Amino acid substitution in the SIM sequence (SIM/M) within the BTB/POZ domain partially reduced K167 SUMOylation activity of NACC1. Overexpression of GFP-NACC1 fusion protein leads to formation of discrete nuclear foci similar to promyelocytic leukemia nuclear bodies (PML-NB), which colocalized with SUMO paralogues (SUMO1/2/3). Both NACC1 nuclear body formation and colocalization with SUMO paralogues were completely suppressed in the GFP-NACC1-SIM/M mutant, whereas they were partially maintained in the NACC1 K167R mutant. Confocal immunofluorescence analysis showed that endogenous and exogenous NACC1 proteins colocalized with endogenous PML protein. A pull-down assay revealed that the consensus motifs of the SUMO acceptor site at K167 and the SIM within the BTB/POZ domain were both necessary for efficient binding to PML protein. Our study demonstrates that NACC1 can be modified by SUMO paralogues, and cooperates with PML protein.


Asunto(s)
Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Represoras/metabolismo , Sumoilación , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Enzimas Ubiquitina-Conjugadoras/metabolismo , Secuencia de Aminoácidos , Células HeLa , Humanos , Espacio Intranuclear/metabolismo , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/patología , Células MCF-7 , Datos de Secuencia Molecular , Proteína de la Leucemia Promielocítica , Transporte de Proteínas
17.
Am J Dermatopathol ; 36(3): 211-6, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24658378

RESUMEN

Methylation and demethylation of histone H3 lysine 9 (H3K9) play a role in the transcriptional regulation of several cancer-related genes and are closely associated with malignant tumor behavior. A novel study has recently demonstrated that SETDB1, a member of the H3K9 methyltransferases, accelerates tumor formation significantly in a zebrafish melanoma model. However, the expression of H3K9 methyltransferases including SETDB1 and demethylases has not been systematically examined in samples of human melanoma. Here, we used immunohistochemistry to examine the expression of the H3K9 methyltransferases, EHMT2 and SETDB1, and a H3K9 demethylase, LSD1, in 67 patients with melanoma. Overexpression of EHMT2, SETDB1, and LSD1 was observed in 14 (21%), 38 (57%), and 53 (79%) of the 67 patients, respectively. A significant relationship was observed between overexpression of EHMT2 or SETDB1 and aggressive tumor behavior such as lymph node metastasis and/or distant metastasis (P < 0.05), whereas no significant relationship was evident for LSD1 immunoreactivity. Univariate log-rank tests demonstrated that patients with melanoma overexpressing EHMT2 had a poorer outcome (P < 0.001), whereas overexpression of SETDB1 or LSD1 had no prognostic impact. These results suggest that overexpression of EHMT2 might be a prognostic marker in patients with melanoma.


Asunto(s)
Antígenos de Histocompatibilidad/biosíntesis , Histona Demetilasas/biosíntesis , N-Metiltransferasa de Histona-Lisina/biosíntesis , Melanoma/enzimología , Proteína Metiltransferasas/biosíntesis , Neoplasias Cutáneas/enzimología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/análisis , Femenino , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Masculino , Melanoma/mortalidad , Melanoma/patología , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Neoplasias Cutáneas/mortalidad , Neoplasias Cutáneas/patología
18.
Life Sci ; 97(2): 137-44, 2014 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-24412389

RESUMEN

AIMS: Epidermal growth factor receptor (EGFR) transactivation induced by angiotensin II (Ang II) participates in the progression of various diseases. A disintegrin and metalloproteinase 17 (ADAM17) is thought to promote renal fibrosis, cardiac hypertrophy with fibrosis and atherosclerosis by activation of the EGFR through secretion of EGFR ligands. The purpose of this study was to investigate whether Ang II-induced EGFR transactivation occurs on hepatic stellate cells (HSCs) and whether the reaction is mediated via ADAM17. MAIN METHODS: Ang II-induced EGFR transactivation and cellular proliferation of the human HSC line LI90 were investigated using Western blotting and ATP assay, respectively. Ang II-induced secretion of mature amphiregulin into the cell culture medium was evaluated by enzyme-linked immunosorbent assay (ELISA). KEY FINDINGS: An inhibitor of ADAM17, TAPI-1, as well as antagonists of EGFR and angiotensin II type-1 receptor (AT1), attenuated Ang II-induced EGFR transactivation and proliferation of LI90 cells. Furthermore, silencing of ADAM17 inhibited Ang II-induced secretion of mature amphiregulin in addition to EGFR transactivation. SIGNIFICANCE: These results indicate that ADAM17 mediates Ang II-induced EGFR transactivation on HSCs, and that this process may participate in the progression of liver fibrosis.


Asunto(s)
Proteínas ADAM/metabolismo , Angiotensina II/metabolismo , Receptores ErbB/metabolismo , Células Estrelladas Hepáticas/metabolismo , Proteínas ADAM/genética , Proteína ADAM17 , Anfirregulina , Western Blotting , Línea Celular , Proliferación Celular , Dipéptidos/farmacología , Progresión de la Enfermedad , Familia de Proteínas EGF , Ensayo de Inmunoadsorción Enzimática , Silenciador del Gen , Glicoproteínas/metabolismo , Humanos , Ácidos Hidroxámicos/farmacología , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Cirrosis Hepática/fisiopatología
20.
J Clin Exp Hematop ; 53(2): 135-40, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23995110

RESUMEN

Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare form of non-Hodgkin lymphoma, in which lymphoma cells infiltrate preferentially into subcutaneous adipose tissue. Although various treatment trials for SPTCL have been attempted, no standardized therapy has been established. Here, we report a case of α/ß(+) T-cell-phenotype SPTCL (SPTCL-AB) with hemophagocytosis (HPS) in a 14-year-old girl, who presented with low-grade fever, general fatigue and chest swelling. Laboratory examinations revealed leukocytopenia, and bone marrow aspiration cytology showed HPS. The diagnosis of SPTCL-AB was made by biopsy on the basis of thickened subcutaneous tissue in the chest wall. Following high-dose chemotherapy (HDT) of BFM-NHL & ALL-90, autologous peripheral blood stem cell transplantation (auto-PBSCT) was performed. The patient responded to the treatment and has remained asymptomatic for 2 years. Our results suggest that a combination of HDT of BFM-NHL & ALL-90 and auto-SCT treatment is effective for SPTCL associated with HPS.


Asunto(s)
Citofagocitosis/inmunología , Linfoma de Células T/inmunología , Paniculitis/inmunología , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biopsia , Médula Ósea/inmunología , Médula Ósea/patología , Femenino , Humanos , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Linfoma de Células T/diagnóstico , Linfoma de Células T/terapia , Imagen por Resonancia Magnética , Paniculitis/diagnóstico , Paniculitis/terapia , Trasplante de Células Madre de Sangre Periférica , Piel/patología , Trasplante Autólogo
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