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1.
PLoS One ; 18(4): e0284744, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37083947

RESUMO

RAS, the most frequently mutated oncogene that drives tumorigenesis by promoting cell proliferation, survival, and motility, has been perceived as undruggable for the past three decades. However, intense research in the past has mainly focused on KRAS mutations, and targeted therapy for NRAS mutations remains an unmet medical need. NRAS mutation is frequently observed in several cancer types, including melanoma (15-20%), leukemia (10%), and occasionally other cancer types. Here, we report using miRNA-708, which targets the distinct 3' untranslated region (3'UTR) of NRAS, to develop miRNA-based precision medicine to treat NRAS mutation-driven cancers. We first confirmed that NRAS is a direct target of miRNA-708. Overexpression of miRNA-708 successfully reduced NRAS protein levels in melanoma, leukemia, and lung cancer cell lines with NRAS mutations, resulting in suppressed cell proliferation, anchorage-independent growth, and promotion of reactive oxygen species-induced apoptosis. Consistent with the functional data, the activities of NRAS-downstream effectors, the PI3K-AKT-mTOR or RAF-MEK-ERK signaling pathway, were impaired in miR-708 overexpressing cells. On the other hand, cell proliferation was not disturbed by miRNA-708 in cell lines carrying wild-type NRAS. Collectively, our data unveil the therapeutic potential of using miRNA-708 in NRAS mutation-driven cancers through direct depletion of constitutively active NRAS and thus inhibition of its downstream effectors to decelerate cancer progression. Harnessing the beneficial effects of miR-708 may therefore offer a potential avenue for small RNA-mediated precision medicine in cancer treatment.


Assuntos
Leucemia , Melanoma , MicroRNAs , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/genética , Melanoma/metabolismo , MicroRNAs/genética , Mutação , Linhagem Celular Tumoral , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas de Membrana/genética , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo
2.
Cell Death Dis ; 12(12): 1090, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34789744

RESUMO

Certain immune cells and inflammatory cytokines are essential components in the tumor microenvironment to promote breast cancer progression. To identify key immune players in the tumor microenvironment, we applied highly invasive MDA-MB-231 breast cancer cell lines to co-culture with human monocyte THP-1 cells and identified CXCL7 by cytokine array as one of the increasingly secreted cytokines by THP-1 cells. Further investigations indicated that upon co-culturing, breast cancer cells secreted CSF1 to induce expression and release of CXCL7 from monocytes, which in turn acted on cancer cells to promote FAK activation, MMP13 expression, migration, and invasion. In a xenograft mouse model, administration of CXCL7 antibodies significantly reduced abundance of M2 macrophages in tumor microenvironment, as well as decreased tumor growth and distant metastasis. Clinical investigation further suggested that high CXCL7 expression is correlated with breast cancer progression and poor overall survival of patients. Overall, our study unveils an important immune cytokine, CXCL7, which is secreted by tumor infiltrating monocytes, to stimulate cancer cell migration, invasion, and metastasis, contributing to the promotion of breast cancer progression.


Assuntos
Neoplasias da Mama/genética , Monócitos/metabolismo , beta-Tromboglobulina/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Xenoenxertos , Humanos , Camundongos , Camundongos SCID , Transfecção , Microambiente Tumoral
3.
Biochem Biophys Res Commun ; 533(3): 467-473, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-32977949

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused by 2019 novel coronavirus (2019-nCoV) has been a crisis of global health, whereas the effective vaccines against 2019-nCoV are still under development. Alternatively, utilization of old drugs or available medicine that can suppress the viral activity or replication may provide an urgent solution to suppress the rapid spread of 2019-nCoV. Andrographolide is a highly abundant natural product of the medicinal plant, Andrographis paniculata, which has been clinically used for inflammatory diseases and anti-viral therapy. We herein demonstrate that both andrographolide and its fluorescent derivative, the nitrobenzoxadiazole-conjugated andrographolide (Andro- NBD), suppressed the main protease (Mpro) activities of 2019-nCoV and severe acute respiratory syndrome coronavirus (SARS-CoV). Moreover, Andro-NBD was shown to covalently link its fluorescence to these proteases. Further mass spectrometry (MS) analysis suggests that andrographolide formed a covalent bond with the active site Cys145 of either 2019-nCoV Mpro or SARS-CoV Mpro. Consistently, molecular modeling analysis supported the docking of andrographolide within the catalytic pockets of both viral Mpros. Considering that andrographolide is used in clinical practice with acceptable safety and its diverse pharmacological activities that could be beneficial for attenuating COVID-19 symptoms, extensive investigation of andrographolide on the suppression of 2019-nCoV as well as its application in COVID-19 therapy is suggested.


Assuntos
Cisteína Endopeptidases/metabolismo , Diterpenos/farmacologia , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo , Betacoronavirus/enzimologia , Domínio Catalítico , Proteases 3C de Coronavírus , Cisteína Endopeptidases/química , Diterpenos/química , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Simulação de Acoplamento Molecular , Conformação Proteica , Multimerização Proteica , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/enzimologia , SARS-CoV-2 , Proteínas não Estruturais Virais/química
4.
Clinics ; 75: e1436, 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1133422

RESUMO

OBJECTIVES: The prevalence of diabetes mellitus has recently increased in Taiwan, and depression is common among these patients. Moreover, a lack of health literacy may lead to depression. In this study, we explored the correlation between health literacy and depression in diabetic women. METHODS: In this cross-sectional study, 152 women with type 2 diabetes mellitus were recruited from the outpatient clinic of a regional teaching hospital in Taiwan. The data were collected through medical records and a self-reported structured questionnaire, which included items on basic attributes, self-rated health status, the Center for Epidemiologic Studies Depression Scale (CES-D), and Chinese Health Literacy Scale for Diabetes (CHLSD). The results were analyzed using descriptive statistical analyses, bivariate correlation tests, and linear regression analyses. RESULTS: One hundred thirty-five valid questionnaires were obtained. Approximately 20% of the participants had a higher tendency toward depression as per their CES-D score, and the CHLSD results showed that 13.33% had poor health literacy. There was a negative correlation between health literacy and depressive tendencies after adjusting for self-rated health status, economic satisfaction status, employment status, and education level using multivariate linear regression analyses. For each 1-point rise in the CHLSD score, the CES-D score decreased by 0.17 points (z=−2.05, p=0.042). CONCLUSIONS: A negative correlation was identified between health literacy and depression. Self-rated health status, economic satisfaction, employment status, and higher education level are factors that also affect depressive tendency among diabetic women.


Assuntos
Humanos , Feminino , Diabetes Mellitus Tipo 2 , Letramento em Saúde , Taiwan , Estudos Transversais , Inquéritos e Questionários , Depressão
6.
Int J Mol Sci ; 18(9)2017 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-28880208

RESUMO

Restoring sufficient vascularity of the ischemia/hypoxia flap is always the critical issue in flap surgeries. In a previous studies microRNA-21 (miR-21) expression was upregulated after rat skin flap surgery. MiR-21 has been reported to be induced by hypoxia and the function of miR-21 involves in the process of angiogenesis. However, the precise regulatory mechanisms in miR-21-mediated pathways are still unclear. These issues were investigated via in vitro and in vivo experiments in this study. In human umbilical vein endothelial cells (HUVEC), the expression of hsa-miR-21-5p was induced after hypoxic culture and the induction of hsa-miR-21-5p was suppressed after sequential normoxic culture. Moreover, transfection of hsa-miR-21-5p mimic enhanced tube formation capacity in normoxia, but attenuated it in hypoxia. Furthermore, bioinformatic analysis suggested that SMAD7 was a predicted target of hsa-miR-21-5p. Our results demonstrated the effect of hsa-miR-21-5p was different on SMAD7 expression in normoxia and hypoxia. In rat skin flaps, blockage of miR-21-5p significantly increased angiogenesis via analysis of color laser Doppler imaging and repressed SMAD7 expression in ischemic skin tissue. Our study showed the opposite effect of miR-21-5p mediating angiogenesis in normoxia and hypoxia, providing important implications regarding the design of novel miRNA-based therapeutic strategies in flap surgeries.


Assuntos
Hipóxia/metabolismo , MicroRNAs/metabolismo , Animais , Western Blotting , Células Endoteliais da Veia Umbilical Humana , Humanos , Hipóxia/genética , Masculino , MicroRNAs/genética , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Proteína Smad7/genética , Proteína Smad7/metabolismo
7.
Int J Mol Sci ; 18(7)2017 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-28718842

RESUMO

Secreted protein acidic and rich in cysteine (SPARC) is a secreted protein which is involved in various biological processes. SPARC expression is associated with tumor metastasis and poor prognosis in several types of cancer. However, the SPARC-induced signaling pathway was not fully understood in head and neck cancer. In this study, our results showed that SPARC treatment promoted cell proliferation and migration in head and neck cancer cell lines FaDu and Detroit 562. In addition, SPARC induced expression of epithelial mesenchymal transition (EMT) regulators, including Slug, Snail, and Twist in Detroit 562. The results of phospho-kinase array analysis showed that SPARC treatment increased phosphorylation of some molecules including protein kinase B (PKB/AKT), ribosomal S6 kinase (RSK), and extracellular signal-regulated kinases (ERK). The expression of SPARC-induced EMT regulator Slug was suppressed by AKT inhibitor, but not ERK and RSK inhibitors. The SPARC expression in grade IV tumor samples is higher when compared to that in grade I-III tumor samples. Our results suggest that SPARC treatment enhances the EMT signaling pathway via activation of AKT, and exogenous SPARC and tumor expressing SPARC might be associated with tumor progression in head and neck cancers.


Assuntos
Movimento Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Osteonectina/genética , Osteonectina/farmacologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Modelos Biológicos , Gradação de Tumores , Osteonectina/metabolismo , Fenótipo , Transdução de Sinais/efeitos dos fármacos
8.
Clin Nucl Med ; 42(2): 138-139, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28005644

RESUMO

The most common metastatic sites of colorectal cancer are the regional lymph nodes, liver, lungs, and peritoneum. Seminal vesicle metastasis from colon adenocarcinoma is not reported yet; the diagnosis could be challenging. We report a case of seminal vesicle metastasis from a primary ascending colon adenocarcinoma in a 49-year-old man, with elevating carcinoembryonic antigen as the only clinical sign. This also highlights the role of F-FDG PET/CT to detect metastatic adenocarcinoma from colon in the genitourinary system.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Neoplasias do Colo/diagnóstico por imagem , Neoplasias dos Genitais Masculinos/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Glândulas Seminais/diagnóstico por imagem , Adenocarcinoma/patologia , Colo Ascendente/diagnóstico por imagem , Neoplasias do Colo/patologia , Fluordesoxiglucose F18 , Neoplasias dos Genitais Masculinos/secundário , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos
10.
PLoS One ; 11(4): e0152770, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27035713

RESUMO

Andrographolide (ANDRO) is a lactone diterpenoid compound present in the medicinal plant Andrographis paniculata which is clinically applied for multiple human diseases in Asia and Europe. The pharmacological activities of andrographolide have been widely demonstrated, including anti-inflammation, anti-cancer and hepatoprotection. However, the pharmacological mechanism of andrographolide remains unclear. Therefore, further characterization on the kinetics and molecular targets of andrographolide is essential. In this study, we described the synthesis and characterization of a novel fluorescent andrographolide derivative (ANDRO-NBD). ANDRO-NBD exhibited a comparable anti-cancer spectrum to andrographolide: ANDRO-NBD was cytotoxic to various types of cancer cells and suppressed the migration activity of melanoma cells; ANDRO-NBD treatment induced the cleavage of heat shock protein 90 (Hsp90) and the downregulation of its client oncoproteins, v-Src and Bcr-abl. Notably, ANDRO-NBD showed superior inhibitory effects to andrographolide in all anticancer assays we have performed. In addition, ANDRO-NBD was further used as a fluorescent probe to investigate the uptake kinetics, cellular distribution and molecular targets of andrographolide. Our data revealed that ANDRO-NBD entered cells rapidly and its fluorescent signal could be detected in nucleus, cytoplasm, mitochondria, and lysosome. Moreover, we demonstrated that ANDRO-NBD was covalently bound to several putative target proteins of andrographolide, including NF-κB and hnRNPK. In summary, we developed a fluorescent andrographolide probe with comparable bioactivity to andrographolide, which serves as a powerful tool to explore the pharmacological mechanism of andrographolide.


Assuntos
Diterpenos/química , Sondas Moleculares/química , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
11.
Kaohsiung J Med Sci ; 31(12): 621-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26709223

RESUMO

Tc-99m phytate hepatic scintigraphy remains the standard method for evaluating the functional features of Kupffer cells. In this study, we demonstrate the variable uptake feature of focal nodular hyperplasia (FNH) in Tc-99m phytate scintigraphy. We reviewed all patients who underwent Tc-99m phytate hepatic scintigraphy between 2008 and 2012 in Kaohsiung Medical University Hospital, Kaohsiung, Taiwan. Cases with FNH were diagnosed on the basis of pathology or at least one or more prior imaging with a periodic clinical follow-up. All patients received a standard protocol of dynamic flow study and planar and Tc-99m phytate single-photon emission computed tomography (E. CAM; Siemens). The correlation of variable nodular radioactivity with parameters such as tumor size and localization was analyzed. In total, 15 lesions of 14 patients in the clinic were diagnosed as FNH. The tumor size was approximately 2.9-7.4 cm (mean size 4.6 cm). Four lesions were larger than 5 cm. The major anatomic distribution was in the right hepatic lobe (10 lesions), particularly in the superior segments (7 lesions). Tc-99m phytate single-photon emission computed tomography imaging for determining the functional features of Kupffer cells included cool/cold (8 lesions), isoradioactive/warm (6 lesions), and hot (1 lesion) patterns of uptake. We did not observe any statistically significant correlation between variable nodular radioactivity and tumor size (p=0.68) or localization (p=0.04). Herein, we demonstrate the variable uptake feature of FNH in Tc-99m phytate scintigraphy. In small FNH tumors (< 5 cm), increased or equal uptake still provided specificity for the differential diagnosis of hepatic solid tumors.


Assuntos
Hiperplasia Nodular Focal do Fígado/diagnóstico por imagem , Fígado/diagnóstico por imagem , Compostos de Organotecnécio/farmacocinética , Ácido Fítico/farmacocinética , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Pessoa de Meia-Idade , Radioatividade , Cintilografia , Adulto Jovem
12.
Chembiochem ; 16(11): 1555-9, 2015 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-26096673

RESUMO

α-L-Fucosidase activity is associated with several diseases. To study the enzymatic activity change under pathological conditions, we developed a quinone methide-generating activity-based probe useful for examining the presence, activity, and localization of human α-L-fucosidase in vivo in the context of Helicobacter pylori infection. In particular, an increase in intracellular fucosidase (Fuca1) activity was found in gastric epithelial cells upon bacterial infection. We further studied the effect of several bacterial stimulants on this enhanced Fuca1 activity and identified lipopolysaccharides to be a major contributing factor.


Assuntos
Helicobacter pylori/fisiologia , Indolquinonas/metabolismo , Sondas Moleculares/metabolismo , alfa-L-Fucosidase/metabolismo , Linhagem Celular Tumoral , Epitélio/microbiologia , Humanos , Lipopolissacarídeos/metabolismo , Estômago/microbiologia
13.
Mutagenesis ; 30(4): 475-85, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25744060

RESUMO

The human JC virus (JCV) is potentially carcinogenic to humans as a Group 2B carcinogen, and it is ubiquitous in human populations. To investigate whether the small tumour (ST) antigen of the JCV contributes to genomic instability, we established cell lines stably expressing the JCV ST and examined its role in DNA repair. Results from host cell reactivation (HCR) assay revealed that the established cell lines exhibited lower nucleotide excision repair (NER) activity than the vector control cells did. The presence of γ-H2AX, a marker of DNA damage, indicated that the established cell line contained more DNA damage foci compared with vector control cells. Furthermore, the results of clonogenic analyses indicated that the JCV ST-expressing cells were more sensitive than the vector control cells to ultraviolet (UV) irradiation and cisplatin treatment. Micronuclei formation assay revealed that the JCV ST-positive cells presented more chromosomal breakages than did the JCV ST-negative cells, particularly after exposure to DNA-damaging agents. The xeroderma pigmentosum Group D protein, a DNA helicase involved in NER, was downregulated in the JCV ST-positive cells in response to UV irradiation. The effect of the protein phosphatase 2A (PP2A) inhibitor okadaic acid on NER was similar to that of the ST, which is a PP2A-binding protein. Therefore, the deactivation of the PP2A might underlie ST-mediated NER inhibition. The results of this study indicate that exposing JCV ST-positive cells to DNA-damaging agents causes genomic instability, which contributes to carcinogenesis. Our data provide further evidence on the association between the JCV ST and human cancer.


Assuntos
Antígenos Virais de Tumores/farmacologia , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Instabilidade Genômica , Vírus JC/fisiologia , Neoplasias Pulmonares/patologia , Western Blotting , Proliferação de Células/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Testes para Micronúcleos , Ácido Okadáico/farmacologia , Proteína Fosfatase 2/antagonistas & inibidores , Proteína Fosfatase 2/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
14.
Pediatr Neonatol ; 51(6): 356-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21146802

RESUMO

Transient neonatal pustular melanosis is mostly found in full-term black infants. It is a benign and self-limited disease, and the etiology is still unknown. We present a full-term female neonate with multiple vesiculopustular and pigmented macular lesions found immediately after her birth. A skin biopsy showed vesicles consisting of intracorneal and subcorneal aggregates of neutrophils, which is compatible with transient neonatal pustular melanosis. Although it is rare in Taiwan and Asian countries, transient neonatal pustular melanosis should always be considered when pustulosis is found in the neonatal period to prevent the use of unnecessary antibiotics. Dermatological consultation and histological confirmation are sometimes required for the final diagnosis.


Assuntos
Vesícula/etiologia , Vesícula/patologia , Melanose/etiologia , Melanose/patologia , Vesícula/terapia , Feminino , Humanos , Recém-Nascido , Melanose/terapia
17.
Int J Dermatol ; 48(3): 307-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19261024

RESUMO

BACKGROUND: Primary essential cutis verticis gyrata (CVG) is characterized by folds and furrows of the scalp, resembling the convoluted appearance of the brain, and is not associated with other abnormalities. Most patients with CVG are treated with surgical methods, such as scalp reduction; however, surgery may not be suitable for patients in whom the area involved is large. METHODS: A 37-year-old man with primary essential CVG was treated with a scalp subcision technique under local anesthesia. RESULTS: A successful cosmetic improvement was obtained. CONCLUSIONS: The scalp subcision technique is a safe procedure and should be a treatment option for primary CVG.


Assuntos
Dermatoses do Couro Cabeludo/cirurgia , Couro Cabeludo/cirurgia , Adulto , Humanos , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos/métodos
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