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1.
BMC Cancer ; 23(1): 1071, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932700

RESUMO

BACKGROUND: Although the prognostic value of the Controlling Nutritional Status (CONUT) score in diffuse large B-cell lymphoma (DLBCL) has been reported in several previous studies, its clinical relevance for the presence of sarcopenia has not been assessed. METHODS: In this study, 305 DLBCL patients were reviewed. They were categorized into normal/mild (n = 219) and moderate/severe (n = 86) CONUT groups. Sarcopenia was assessed using the L3-skeletal muscle index measured by baseline computed tomography imaging. Based on CONUT score and sarcopenia, patients were grouped: A (normal/mild CONUT and no sarcopenia), B (either moderate/severe CONUT or sarcopenia, but not both), and C (both moderate/severe CONUT and sarcopenia). RESULTS: The moderate/severe CONUT group showed higher rates of ≥ grade 3 febrile neutropenia, thrombocytopenia, non-hematologic toxicities, and early treatment discontinuation not related to disease progression, compared to the normal/mild CONUT group. The moderate/severe CONUT group had a lower complete response rate (58.1% vs. 80.8%) and shorter median overall survival (18.5 vs. 162.6 months) than the normal/mild group. Group C had the poorest prognosis with a median survival of 8.6 months, while groups A and B showed better outcomes (not reached and 60.1 months, respectively). Combining CONUT score and sarcopenia improved the predictive accuracy of the Cox regression model (C-index: 0.763), compared to the performance of using either CONUT score (C-index: 0.754) or sarcopenia alone (C-index: 0.755). CONCLUSIONS: In conclusion, the moderate/severe CONUT group exhibited treatment intolerance, lower response, and poor prognosis. Additionally, combining CONUT score and sarcopenia enhanced predictive accuracy for survival outcomes compared to individual variables.


Assuntos
Linfoma Difuso de Grandes Células B , Sarcopenia , Humanos , Prognóstico , Músculo Esquelético/patologia , Estado Nutricional , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Estudos Retrospectivos , Avaliação Nutricional
2.
BMC Cancer ; 20(1): 1180, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33267790

RESUMO

BACKGROUND: Anchoring filament protein ladinin-1 (LAD1) was related to the aggressive progression of breast, lung, laryngeal and thyroid cancers. However, the association of LAD1 with colorectal cancer remained unknown. Here, to determine the relationship of LAD1 with colorectal cancer progression, we explored the effect of LAD1 loss on the malignant features of colorectal cancer cells. METHODS: We constructed LAD1-depleted cell lines and examined the effect of LAD1 deficiency on the phenotypic and molecular features of colorectal cancer cells in vitro. The function of LAD1 in metastasis in vivo was examined by establishing a spleen-to-liver metastasis mouse model. LAD1 protein expression in colorectal cancer patient specimens was assessed by immunohistochemistry of tumor microarrays. RESULTS: We found that LAD1 was abundant in most colorectal cancer cells. In addition, high expression of LAD1 significantly correlated with poor patient outcome. LAD1 depletion inhibited the migration and invasion of two different colorectal cancer cell lines, SW620 and Caco-2, without affecting their proliferation. In addition, LAD1 loss led to defects in liver metastasis of SW620 cells in the mouse model. Immunohistochemistry of colorectal cancer tissues revealed LAD1 enrichment in metastatic tissues compared to that in primary tumor and normal tissues. CONCLUSION: These results suggest that LAD1 expression is associated with the metastatic progression of colorectal cancer by promoting the migration and invasion of cancer cells.


Assuntos
Autoantígenos/metabolismo , Neoplasias Colorretais/metabolismo , Colágenos não Fibrilares/metabolismo , Animais , Neoplasias Colorretais/mortalidade , Feminino , Camundongos , Metástase Neoplásica , Análise de Sobrevida , Transfecção , Colágeno Tipo XVII
3.
Int J Mol Sci ; 21(6)2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32183071

RESUMO

Mesenchymal stem cells, also known as multipotent stromal progenitor cells, can differentiate into cells of mesodermal lineage. Gangliosides are sialic acid-conjugated glycosphingolipids that are believed to regulate cell differentiation and several signaling molecules. These molecules are localized in glycosphingolipid-enriched microdomains on the cell surface and are regulated by glycosphingolipid composition. Transforming growth factor-beta (TGF-ß) signaling plays a critical role in chondrogenic differentiation. However, the role of gangliosides in chondrogenesis is not understood. In this study, the relationship between the ganglioside GM3 and TGF-ß activation, during chondrogenic differentiation, was investigated using an aggregate culture of human synovial membrane-derived mesenchymal stem cells. We showed that the gangliosides GM3 and GD3 were expressed after the chondrogenic differentiation of hSMSC aggregates. To test whether GM3 affected the chondrogenic differentiation of hSMSC aggregates, we used GM3 treatment during chondrogenic differentiation. The results showed that the group treated with 5 µM GM3 had higher expression of chondrogenic specific markers, increased toluidine blue, and safranin O staining, and increased accumulation of glycosaminoglycans compared with the untreated group. Furthermore, GM3 treatment enhanced TGF-ß signaling via SMAD 2/3 during the chondrogenic differentiation of hSMSC aggregates. Taken together, our results suggested that GM3 may be useful in developing therapeutic agents for cell-based articular cartilage regeneration in articular cartilage disease.


Assuntos
Diferenciação Celular , Condrócitos/metabolismo , Gangliosídeo G(M3)/farmacologia , Células-Tronco Mesenquimais/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Células Cultivadas , Condrócitos/citologia , Condrogênese , Glicosaminoglicanos/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Transdução de Sinais , Proteínas Smad/metabolismo , Membrana Sinovial/citologia , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima
4.
Int J Mol Sci ; 21(21)2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33171878

RESUMO

Mesenchymal stem cells (MSCs) are multipotent stem cells that can be isolated from various tissues in the adult body. MSCs should be characterized by three criteria for regenerative medicine. MSCs must (1) adhere to plastic surfaces, (2) express specific surface antigens, and (3) differentiate into mesodermal lineages, including chondrocytes, osteoblasts, and adipocytes, in vitro. Interestingly, MSCs have immunomodulatory features and secrete trophic factors and immune receptors that regulate the microenvironment in host tissue. These specific and unique therapeutic properties make MSCs ideal as therapeutic agents in vivo. Specifically, pre-clinical and clinical investigators generated inflammatory and fibrotic diseases models, and then transplantation of MSCs into diseases models for therapeutic effects investigation. In this review, we characterize MSCs from various tissues and describe their applications for treating various inflammation and fibrotic diseases.


Assuntos
Fibrose/terapia , Inflamação/terapia , Células-Tronco Mesenquimais/metabolismo , Adipócitos/citologia , Animais , Diferenciação Celular , Condrócitos/citologia , Humanos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Osteoblastos/citologia , Medicina Regenerativa/métodos
5.
Biochem Biophys Res Commun ; 508(1): 275-281, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30497779

RESUMO

Precise cell cycle regulation is critical to prevent aberrant cell proliferation and cancer progression. Cks1 was reported to be an essential accessory factor for SCFSkp2, the ubiquitin ligase that targets p27Kip1 for proteasomal degradation; these actions drive mammalian cell transition from G1 to S phase. In this study, we investigated the role played by Cks1 in the growth and progression of human hepatocellular carcinoma (HCC) cells. Silencing Cks1 expression abrogated osteopontin (OPN) expression in a p27Kip1-dependent manner in Huh7 HCC cells. OPN increased the proliferation, migration and invasion of Huh7 cells. Pharmacological inhibitor studies demonstrated that ERK1/2 signaling is responsible mainly for Cks1-mediated OPN expression. Cks1 appears to regulate ERK1/2 signaling through the expression of dual-specificity phosphatase 16 (DUSP16) because both Cks1 knockdown, which leads to DUSP16 upregulation, and DUSP16 overexpression decreased ERK1/2 phosphorylation and the resulting OPN expression. The same is true for the Cks1-mediated increases in p27Kip1, suggesting that Cks1 regulates OPN expression through activating ERK1/2 signaling either by suppressing DUSP16 expression or by a p27Kip1-dependent mechanism. Cks1 and OPN expression levels were significantly higher, but DUSP16 expression levels were significantly lower in HCC tissues than in normal liver tissues. Both Cks1 and OPN expression were negatively correlated with DUSP16 expression, whereas Cks1 expression was positively correlated with OPN expression. Moreover, combined panels for the expression levels of Cks1, DUSP16 and OPN showed significant prognostic power for the risk assessment of HCC patient overall survival. In conclusion, our data propose a novel function for Cks1 as a tumor promoter through the expression of the strongly oncogenic protein OPN in HCC.


Assuntos
Quinases relacionadas a CDC2 e CDC28/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Osteopontina/biossíntese , Osteopontina/genética , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Neoplasias Hepáticas/diagnóstico , Osteopontina/metabolismo
6.
Biochem Biophys Res Commun ; 478(1): 403-409, 2016 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-27422607

RESUMO

The heterogeneity and genetic instability of ovarian cancer cells often lead to the development of drug resistance, closely related with the increased cancer-related mortality. In this study, we investigated the role of dual-specificity phosphatase 1 (DUSP1) in the development of the resistance in human ovarian cancer cells against paclitaxel. Overexpression of DUSP1 in HeyA8 human ovarian cancer cells (HeyA8-DUSP1) up-regulated the expression of the drug efflux pump, p-glycoprotein. Consequently, HeyA8-DUSP1 cells are highly resistant to paclitaxel, with the resistance comparable to that of a multi-drug resistance cell line (HeyA8-MDR). Moreover, over expression of DUSP1 significantly increased the activation of p38 MAPK, leaving the activation of ERK1/2 and JNK1/2 unaffected. Pharmacological suppression of p38 MAPK activity prevents the up-regulation of p-glycoprotein expression and the consequent resistance against paclitaxel in HeyA8-DUSP1 cells. By contrast, HeyA8-MDR cells expressed a significantly higher level of DUSP1, but treatment with small interference RNA against DUSP1 significantly suppressed the expression of p-glycoprotein and the resistance against paclitaxel in HeyA8-MDR cells. Ectopic expression of MKK3, an upstream activator of p38 MAPK, significantly up-regulated the expression of p-glycoprotein and increased the consequent resistance against paclitaxel in HeyA8 cells. Collectively, these data indicated that DUSP1 may induce the resistance against paclitaxel through the p38 MAPK-mediated overexpression of p-glycoprotein in human ovarian cancer cells.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Fosfatase 1 de Especificidade Dupla/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Paclitaxel/administração & dosagem , Antineoplásicos Fitogênicos/administração & dosagem , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/fisiologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Ovarianas/patologia , Resultado do Tratamento
7.
Korean J Physiol Pharmacol ; 20(1): 91-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26807028

RESUMO

(E)-3-(3-methoxyphenyl)-1-(2-pyrrolyl)-2-propenone (MPP) is an aldol condensation product resulting from pyrrole-2-carbaldehyde and m- and p- substituted acetophenones. However, its biological activity has not yet been evaluated. Since it has been reported that some propenone-type compounds display anti-inflammatory activity, we investigated whether MPP could negatively modulate inflammatory responses. To do this, we employed lipopolysaccharide (LPS)-stimulated macrophage-like RAW264.7 cells and examined the inhibitory levels of nitric oxide (NO) production and transcriptional activation, as well as the target proteins involved in the inflammatory signaling cascade. Interestingly, MPP was found to reduce the production of NO in LPS-treated RAW264.7 cells, without causing cytotoxicity. Moreover, this compound suppressed the mRNA levels of inflammatory genes, such as inducible NO synthase (iNOS) and tumor necrosis factor (TNF)-α. Using luciferase reporter gene assays performed in HEK293 cells and immunoblotting analysis with nuclear protein fractions, we determined that MPP reduced the transcriptional activation of nuclear factor (NF)-κB. Furthermore, the activation of a series of upstream signals for NF-κB activation, composed of Src, Syk, Akt, and IκBα, were also blocked by this compound. It was confirmed that MPP was able to suppress autophosphorylation of overexpressed Src and Syk in HEK293 cells. Therefore, these results suggest that MPP can function as an anti-inflammatory drug with NF-κB inhibitory properties via the suppression of Src and Syk.

8.
Phys Chem Chem Phys ; 17(29): 19096-103, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26126667

RESUMO

We synthesized a series of purely organic phosphors, bromobenzaldehyde derivatives, with varying conjugation length to investigate the effects of conjugation length on their phosphorescence emission properties. As the conjugation length increases phosphorescence efficiency decreases with a redshift in the emission color at 77 K. Our computational results imply that this correlation is related to the intersystem crossing rate and that the rate is determined by spin-orbit coupling strength rather than by simply the energy difference between the lowest lying singlet and triplet states. TD-DFT calculations show that the S1 → T1 transition occurs more dominantly than the S1 → T2 transition for all cases. Moreover, singlet excited states are localized on the aldehyde functional group, regardless of the conjugation length, while triplet excited states are evenly distributed over the conjugated backbone. Consequently, as the conjugation length increases, the larger spatial separation between singlet and triplet states diminishes the spin-orbit coupling efficiency, resulting in reduced phosphorescence.

9.
Nat Mater ; 12(7): 659-64, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23524374

RESUMO

Conjugated polymers with a one-dimensional p-orbital overlap exhibit optoelectronic anisotropy. Their unique anisotropic properties can be fully realized in device applications only when the conjugated chains are aligned. Here, we report a molecular design principle of conjugated polymers to achieve concentration-regulated chain planarization, self-assembly, liquid-crystal-like good mobility and non-interdigitated side chains. As a consequence of these intra- and intermolecular attributes, chain alignment along an applied flow field occurs. This liquid-crystalline conjugated polymer was realized by incorporating intramolecular sulphur-fluorine interactions and bulky side chains linked to a tetrahedral carbon having a large form factor. By optimizing the polymer concentration and the flow field, we could achieve a high dichroic ratio of 16.67 in emission from conducting conjugated polymer films. Two-dimensional grazing-incidence X-ray diffraction was performed to analyse a well-defined conjugated polymer alignment. Thin-film transistors built on highly aligned conjugated polymer films showed more than three orders of magnitude faster carrier mobility along the conjugated polymer alignment direction than the perpendicular direction.

10.
Thorac Cancer ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886905

RESUMO

BACKGROUND: Systemic inflammation is believed to contribute to small cell lung cancer (SCLC) progression, but the underlying relationship remains unclear. Lipocalin-2, a potential biomarker of inflammation, has been implicated in various cancers but its prognostic value in SCLC is underexplored. METHODS: We retrospectively analyzed 191 patients with SCLC (72 with limited-stage [LD] and 119 with extensive-stage) treated using platinum-based chemotherapy. Lipocalin-2 expression was evaluated using immunohistochemistry. Optimal cutoff values for lipocalin-2 and neutrophil-to-lymphocyte ratio (NLR) were determined using time-dependent receiver operating characteristic curve analysis. The pectoralis muscle index was used to assess sarcopenia. RESULTS: In LD-SCLC, high lipocalin-2 expression was associated with worse progression-free survival (PFS; median: 7.0 vs. 15.9 months, p = 0.015) and overall survival (OS; median: 12.9 vs. 30.3 months, p = 0.035) compared with low lipocalin-2 expression. Patients were stratified into three prognostic groups by combining lipocalin-2 with NLR: low lipocalin-2/low NLR, high lipocalin-2/low NLR or low lipocalin-2/high NLR, and high lipocalin-2/high NLR (median PFS: 17.3 vs. 11.0 vs. 6.3 months, p = 0.004; median OS: 30.5 vs. 17.3 vs. 8.6 months, p = 0.002). Similar trends were observed when combining lipocalin-2 with the pectoralis muscle index. High lipocalin-2 expression was also associated with lower complete response rates (18.9% vs. 34.3%, p = 0.035). No significant prognostic implications were found for lipocalin-2 in extensive-stage SCLC. CONCLUSIONS: High lipocalin-2 expression is potentially associated with poorer survival in LD-SCLC. Combining lipocalin-2 with other inflammation-related markers could improve prognostic stratification.

11.
World J Clin Cases ; 11(26): 6200-6205, 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37731550

RESUMO

BACKGROUND: Mixed-phenotype acute leukemia (MPAL) is characterized by acute undifferentiated leukemia with blasts co-expressing myeloid and lymphoid antigens. However, consensus regarding the ideal management strategy for MPAL is yet to be established, owing to its rarity. CASE SUMMARY: A 55-year-old male was diagnosed with T/myeloid MPAL. Vincristine, prednisolone, daunorubicin, and L-asparaginase were administered as induction chemotherapy. Septic shock occurred 10 days after induction, and bone marrow examination following recovery from sepsis revealed refractory disease. Venetoclax and decitabine were administered as chemotherapy-free induction therapy to reduce the infection risk. There were no serious infections, including febrile neutropenia, at the end of the treatment. After receiving two additional cycles of venetoclax/decitabine, the patient underwent haploidentical peripheral blood stem-cell transplantation and achieved complete response (CR) to treatment. CONCLUSION: CR was maintained in a patient with MPAL who underwent haploidentical peripheral blood stem-cell transplantation after additional venetoclax/decitabine cycles.

12.
Int J Oncol ; 62(1)2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36453252

RESUMO

Endothelin receptor A (EDNRA) has been reported to play various crucial physiological roles and has been shown to be associated with the pathology of several diseases, including colorectal cancer (CRC). However, the molecular mechanisms of EDNRA in the development of human CRC have not been fully elucidated to date. In this context, the present study was performed to investigate biological functions and novel downstream signaling pathways affected by EDNRA, during CRC progression. First, using public data repositories, it was observed that the EDRNA expression levels were markedly increased in CRC tissues, as compared to normal tissues. Patients with CRC with an increased EDNRA expression exhibited a significantly decreased survival rate in comparison with those with a lower EDNRA expression. Furthermore, a positive correlation between the levels of EDNRA and its ligand, EDN1, was found in CRC tissues. The ectopic expression of EDNRA or its ligand, EDN1, promoted, whereas the silencing of EDNRA or EDN1 decreased cell proliferation and migration in vitro. To elucidate the signaling pathways involved in the regulation of EDNRA expression in CRC cells, a phosphokinase array analysis was performed, and it was observed that the knockdown of EDNRA substantially suppressed the phosphorylation of signal transducer and activator of transcription 3 (STAT3) in CRC cells. Of note, STAT3 silencing simultaneously decreased EDN1 and EDNRA expression, with the expression of EDN1 and/or EDNRA appearing to be directly regulated by binding STAT3 to their promoter region, according to chromatin immunoprecipitation and promoter assays, ultimately indicating a positive feedback loop in the expression of EDNRA and EDN1. It was also observed that treatment with an EDNRA antagonist (macitentan), alone or in combination with cisplatin, suppressed cell growth and migration ability, and induced cell apoptosis. Collectively, these data suggest a critical role of the EDN1/EDNRA signaling pathway in CRC progression. Thus, the pharmacological intervention of this signaling pathway may prove to be a potential therapeutic approach for patients with CRC.


Assuntos
Neoplasias Colorretais , Fator de Transcrição STAT3 , Humanos , Fosforilação , Fator de Transcrição STAT3/genética , beta-Arrestinas , Receptores de Endotelina , Ligantes , Neoplasias Colorretais/genética
13.
Biochem Biophys Res Commun ; 424(4): 765-70, 2012 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-22809505

RESUMO

Somatic cell nuclear transfer (SCNT) has been established for the transmission of specific nuclear DNA. However, the fate of donor mitochondrial DNA (mtDNA) remains unclear. Here, we examined the fate of donor mtDNA in recloned pigs through third generations. Fibroblasts of recloned pigs were obtained from offspring of each generation produced by fusion of cultured fibroblasts from a Minnesota miniature pig (MMP) into enucleated oocytes of a Landrace pig. The D-loop regions from the mtDNA of donor and recipient differ at nucleotide sequence positions 16050 (A→T), 16062 (T→C), and 16135 (G→A). In order to determine the fate of donor mtDNA in recloned pigs, we analyzed the D-loop region of the donor's mtDNA by allele-specific PCR (AS-PCR) and real-time PCR. Donor mtDNA was successfully detected in all recloned offspring (F1, F2, and F3). These results indicate that heteroplasmy that originate from donor and recipient mtDNA is maintained in recloned pigs, resulting from SCNT, unlike natural reproduction.


Assuntos
Clonagem de Organismos , DNA Mitocondrial/genética , Técnicas de Transferência Nuclear , Porco Miniatura/genética , Animais , Sequência de Bases , DNA Mitocondrial/análise , DNA Mitocondrial/química , Fibroblastos/metabolismo , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Oócitos/metabolismo , Suínos
14.
ISME J ; 16(5): 1205-1221, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34972816

RESUMO

The human microbiome plays an essential role in the human immune system, food digestion, and protection from harmful bacteria by colonizing the human intestine. Recently, although the human microbiome affects colorectal cancer (CRC) treatment, the mode of action between the microbiome and CRC remains unclear. This study showed that propionate suppressed CRC growth by promoting the proteasomal degradation of euchromatic histone-lysine N-methyltransferase 2 (EHMT2) through HECT domain E3 ubiquitin protein ligase 2 (HECTD2) upregulation. In addition, EHMT2 downregulation reduced the H3K9me2 level on the promoter region of tumor necrosis factor α-induced protein 1 (TNFAIP1) as a novel direct target of EHMT2. Subsequently, TNFAIP1 upregulation induced the apoptosis of CRC cells. Furthermore, using Bacteroides thetaiotaomicron culture medium, we confirmed EHMT2 downregulation via upregulation of HECTD2 and TNFAIP1 upregulation. Finally, we observed the synergistic effect of propionate and an EHMT2 inhibitor (BIX01294) in 3D spheroid culture models. Thus, we suggest the anticancer effects of propionate and EHMT2 as therapeutic targets for colon cancer treatment and may provide the possibility for the synergistic effects of an EHMT2 inhibitor and microbiome in CRC treatment.


Assuntos
Neoplasias Colorretais , Microbiota , Ubiquitina-Proteína Ligases/metabolismo , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Propionatos , Regulação para Cima
15.
J Am Chem Soc ; 131(17): 6124-32, 2009 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-19354240

RESUMO

The ability to control the molecular organization of electronically active liquid-crystalline polymer semiconductors on surfaces provides opportunities to develop easy-to-process yet highly ordered supramolecular systems and, in particular, to optimize their electrical and environmental reliability in applications in the field of large-area printed electronics and photovoltaics. Understanding the relationship between liquid-crystalline nanostructure and electrical stability on appropriate molecular surfaces is the key to enhancing the performance of organic field-effect transistors (OFETs) to a degree comparable to that of amorphous silicon (a-Si). Here, we report a novel donor-acceptor type liquid-crystalline semiconducting copolymer, poly(didodecylquaterthiophene-alt-didodecylbithiazole), which contains both electron-donating quaterthiophene and electron-accepting 5,5'-bithiazole units. This copolymer exhibits excellent electrical characteristics such as field-effect mobilities as high as 0.33 cm(2)/V.s and good bias-stress stability comparable to that of amorphous silicon (a-Si). Liquid-crystalline thin films with structural anisotropy form spontaneously through self-organization of individual polymer chains as a result of intermolecular interactions in the liquid-crystalline mesophase. These thin films adopt preferential well-ordered intermolecular pi-pi stacking parallel to the substrate surface. This bottom-up assembly of the liquid-crystalline semiconducting copolymer enables facile fabrication of highly ordered channel layers with remarkable electrical stability.


Assuntos
Polímeros/química , Semicondutores , Substâncias Macromoleculares/química , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície , Transistores Eletrônicos
16.
Biochem Biophys Res Commun ; 387(2): 266-71, 2009 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-19580786

RESUMO

Human dental pulp-derived stem cells (hDPSCs) have been considered alternative sources of adult stem cells because of their potential to differentiate into multiple cell lineages. This study investigated the possible role of gangliosides in the neural differentiation of hDPSCs. When hDPSCs were cultured under neural differentiation conditions, expression of neural cell marker genes such as Nestin, MAP-2, and NeuN was detected. Immunostaining and high-performance thin-layer chromatography analysis showed that an increase in ganglioside biosynthesis was associated with neural differentiation of hDPSCs. Specifically, a significant increase in GD3 and GD1a expression was observed during neural differentiation. To confirm the role of gangliosides in neural differentiation, ganglioside biosynthesis was inhibited in hDPSCs by knockdown of UDP-glucose ceramide glucosyltransferase (Ugcg), which prevented differentiation into neural cells. These results suggest that gangliosides may play a role in the neural differentiation process of hDPSCs.


Assuntos
Polpa Dentária/citologia , Gangliosídeos/biossíntese , Neurogênese , Células-Tronco/citologia , Linhagem Celular , Polpa Dentária/metabolismo , Gangliosídeos/antagonistas & inibidores , Técnicas de Silenciamento de Genes , Glucosiltransferases/antagonistas & inibidores , Glucosiltransferases/genética , Humanos , Células-Tronco/metabolismo
17.
Genes (Basel) ; 10(11)2019 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-31717435

RESUMO

Increasing evidence has demonstrated that increased expression of cyclin-dependent kinase regulatory subunit 1B (CKS1B) is associated with the pathogenesis of many human cancers, including colorectal cancer (CRC). However, the regulatory mechanisms underlying the expression of CKS1B in CRC are not completely understood. Here, we investigate the role played by microRNAs in the expression of CKS1B and carcinogenesis in CRC. Among the six microRNAs predicted to target CKS1B gene expression, only miR-1258 was revealed to downregulate CKS1B expression through binding to its 3'-UTR region, as ectopic miR-1258 expression suppressed CKS1B expression and vice versa. In CRC, miR-1258 expression also decreased cell proliferation and migration in vitro and tumor growth in vivo, similar to cells with silenced CKS1B expression. Considering the highly increased levels of CKS1B and decreased expression of miR-1258 in tumors from CRC patients, these findings suggest that miR-1258 may play tumor-suppressive roles by targeting CKS1B expression in CRC. However, the therapeutic significance of these findings should be evaluated in clinical settings.


Assuntos
Quinases relacionadas a CDC2 e CDC28/genética , Neoplasias Colorretais/genética , MicroRNAs/genética , Animais , Quinases relacionadas a CDC2 e CDC28/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Células HT29 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Int J Cancer ; 122(1): 100-7, 2008 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17764107

RESUMO

It has been proposed that Wnt signaling pathway may be a key radioprotective mechanism in irradiated cancer cells; however, the specific radioresistance mechanisms remain not to be fully clarified. Here we elucidate a novel signaling pathway of radioresistance in head and neck cancer (HNC) cell lines involving interactions among the Wnt signaling pathway, cyclooxygenase-2 (COX-2) and Ku expression. Activation of the Wnt signaling pathway by (2'Z,3'E)-6-bromoindirubin-3'-oxime (BIO) resulted in beta-catenin cytoplasmic accumulation and translocation to the nucleus, upregulated Ku expression and increased radioresistance in the COX-2-expressing HNC cell line. In contrast, Wnt singaling activation by BIO had no effects on Ku expression and radiosensitivity in a HNC cell line negative for COX-2. Interactions between Wnt singaling and Ku were indirectly regulated by COX-2. Blockage of COX-2 signaling led to the suppression of beta-catenin-induced Ku expression, and to consequent recovery of the radiosensitivity in HNC cells. Our results conclusively suggest that beta-catenin plays a pivotal role in the regulation of Ku expression via the proposed COX-2 intracellular pathway, thus supporting a novel radioresistance mechanism of HNC.


Assuntos
Ciclo-Oxigenase 2/metabolismo , DNA Helicases/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Proteínas Wnt/metabolismo , Western Blotting , Núcleo Celular/metabolismo , Ciclo-Oxigenase 2/química , Ciclo-Oxigenase 2/genética , Citoplasma/metabolismo , DNA Helicases/genética , Imunofluorescência , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Marcação In Situ das Extremidades Cortadas , Indóis/farmacologia , Autoantígeno Ku , Oximas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Tolerância a Radiação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Células Tumorais Cultivadas , beta Catenina/metabolismo
19.
Br J Pharmacol ; 175(3): 485-500, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29139561

RESUMO

BACKGROUND AND PURPOSE: 5-HT4 receptor agonists have been shown to be effective at treating various gastrointestinal tract disorders. However, a lack of selectivity against off-targets has been a limiting factor for their clinical use. EXPERIMENTAL APPROACH: The binding affinity and selectivity of YH12852 for human 5-HT4(a) receptor in CHO-K1 cells were evaluated using radioligand binding assays, and agonistic activity was assessed using a ß-lactamase reporter system. Contractile activity and propulsive motility were measured in the guinea pig isolated distal colon. Its prokinetic effect on the gastrointestinal tract was evaluated in guinea pigs, dogs and monkeys. Its tissue distribution was evaluated in rats. KEY RESULTS: YH12852 exhibited high affinity and potency for human recombinant 5-HT4(a) receptor with high selectivity over other 5-HT and non-5-HT receptors, ion channels, enzymes and transporters. YH12852 induced contractions and increased propulsive motility in guinea pig isolated colon. These effects were abolished by the 5-HT4 receptor antagonist GR113808. YH12852 increased defecation more effectively than prucalopride in guinea pigs and dogs and improved gastric emptying more effectively than mosapride in guinea pigs, dogs and monkeys. YH12852 was highly distributed to the gastrointestinal tract as the target organ. CONCLUSION AND IMPLICATIONS: The high in vitro potency and selectivity of YH12852 for 5-HT4 receptor translated into potent in vivo efficacy with good tolerability. YH12852 significantly improved both upper and lower bowel motility in the animal models tested and has the potential to address considerable unmet needs in patients with functional constipation, gastroparesis or both.


Assuntos
Colo/efeitos dos fármacos , Motilidade Gastrointestinal/efeitos dos fármacos , Intestino Delgado/efeitos dos fármacos , Receptores 5-HT4 de Serotonina/metabolismo , Agonistas do Receptor 5-HT4 de Serotonina/metabolismo , Agonistas do Receptor 5-HT4 de Serotonina/farmacologia , Animais , Células CHO , Colo/fisiologia , Cricetinae , Cricetulus , Cães , Relação Dose-Resposta a Droga , Motilidade Gastrointestinal/fisiologia , Humanos , Intestino Delgado/fisiologia , Macaca fascicularis , Masculino , Pirimidinas , Ratos , Ratos Sprague-Dawley
20.
Biomaterials ; 28(16): 2667-76, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17335894

RESUMO

The inhibitory efficacies of new bile acid acylated-heparin derivative (heparin-DOCA) were evaluated on experimental lung metastasis. We evaluated the effect of heparin-DOCA on intercellular interactions including those between B16F10 and thrombin-activated platelets and TNF-alpha-activated HUVECs, and between B16F10 and immobilized mouse P-selectin. In addition, the inhibitory effects of heparin-DOCA on adhesion and invasion of B16F10 to Matrigel were studied. In an animal mouse study, the blood clot formation and the retention of red fluorescence protein (RFP)-B16F10 in lungs were assessed after heparin-DOCA and RFP-B16F10 intravenous administration. Furthermore, we investigated the anti-metastatic effect of heparin-DOCA against lung metastasis induced by B16F10 and SCC7. Heparin-DOCA inhibited intercellular interactions between B16F10 and activated platelets or activated HUVECs by blocking P- and E-selectin-mediated interactions. Moreover, it reduced adhesion and invasion of B16F10 to ECM, thereby affecting the reduction of early retention of B16F10 in the lung. Heparin-DOCA attenuated lung colony formation on the surfaces and in interior of the lung, and attenuated metastasis by B16F10 and SCC7. These results suggest that heparin-DOCA may have potentials as therapeutic agent that prevents tumor metastasis and progression.


Assuntos
Antineoplásicos , Ácidos e Sais Biliares , Heparina , Neoplasias Pulmonares , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/uso terapêutico , Ácidos e Sais Biliares/química , Ácidos e Sais Biliares/metabolismo , Ácidos e Sais Biliares/uso terapêutico , Adesão Celular , Linhagem Celular , Selectina E/metabolismo , Matriz Extracelular/metabolismo , Heparina/análogos & derivados , Heparina/química , Heparina/metabolismo , Heparina/uso terapêutico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Teste de Materiais , Camundongos , Metástase Neoplásica , Transplante de Neoplasias , Neoplasias Experimentais , Selectina-P/metabolismo
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