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1.
Cells ; 11(19)2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-36231010

RESUMO

Oral cancer is a fatal disease, and its incidence in Taiwan is increasing. Thyroid hormone as L-thyroxine (T4) stimulates cancer cell proliferation via a receptor on integrin αvß3 of plasma membranes. It also induces the expression of programmed death-ligand 1 (PD-L1) and cell proliferation in cancer cells. Thyroid hormone also activates ß-catenin-dependent cell proliferation in cancer cells. However, the relationship between PD-L1 and cancer proliferation is not fully understood. In the current study, we investigated the role of inducible thyroid hormone-induced PD-L1-regulated gene expression and proliferation in oral cancer cells. Thyroxine bound to integrin αvß3 to induce PD-L1 expressions via activation of ERK1/2 and signal transducer and activator of transcription 3 (STAT3). Inactivated STAT3 inhibited PD-L1 expression and nuclear PD-L1 accumulation. Inhibition of PD-L1 expression reduced ß-catenin accumulation. Furthermore, nuclear PD-L1 formed a complex with nuclear proteins such as p300. Suppression PD-L1 expression by shRNA blocked not only expression of PD-L1 and ß-catenin but also signal transduction, proliferative gene expressions, and cancer cell growth. In summary, thyroxine via integrin αvß3 activated ERK1/2 and STAT3 to stimulate the PD-L1-dependent and ß-catenin-related growth in oral cancer cells.


Assuntos
Antígeno B7-H1 , Neoplasias Bucais , Antígeno B7-H1/metabolismo , Humanos , Integrina alfaVbeta3/metabolismo , Neoplasias Bucais/metabolismo , Proteínas Nucleares/metabolismo , RNA Interferente Pequeno , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Hormônios Tireóideos , Tiroxina/farmacologia , beta Catenina/metabolismo
2.
Front Cell Dev Biol ; 10: 862045, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36111333

RESUMO

Reduced fertility associated with normal aging may reflect the over-maturity of oocytes. It is increasingly important to reduce aging-induced infertility since recent trends show people marrying at later ages. 2,3,5,4'-Tetrahydroxystilbene-2-O-ß-D-glucoside (THSG), a polyphenol extracted from Polygonum multiflorum, has been reported to have anti-inflammatory and anti-aging properties. To evaluate whether THSG can reduce aging-related ovarian damage in a female mouse model of aging, THSG was administered by gavage at a dose of 10 mg/kg twice weekly, starting at 4 weeks of age in a group of young mice. In addition, the effect of THSG in a group of aged mice was also studied in mice starting at 24 weeks of age. The number of oocytes in the THSG-fed group was higher than in the untreated control group. Although the percentage of secondary polar bodies (PB2) decreased during aging in the THSG-fed group, it decreased much more slowly than in the age-matched control group. THSG administration increased the quality of ovaries in young mice becoming aged. Western blotting analyses also indicated that CYP19, PR-B, and ER-ß expressions were significantly increased in 36-week-old mice. THSG also increased oocyte numbers in aged mice compared to mice without THSG fed. Studies of qPCR and immunohistochemistry (IHC) analyses of ovaries in the aged mice groups were conducted. THSG increased gene expression of anti-Müllerian hormone (AMH), a biomarker of oocyte number, and protein accumulation in 40-week-old mice. THSG increased the expression of pgc1α and atp6, mitochondrial biogenesis-related genes, and their protein expression. THSG also attenuated the fading rate of CYP11a and CYP19 associated with sex hormone synthesis. And THSG maintains a high level of ER-ß expression, thereby enhancing the sensitivity of estrogen. Our findings indicated that THSG increased or extended gene expression involved in ovarian maintenance and rejuvenation in young and aged mice. On the other hand, THSG treatments significantly maintained oocyte quantity and quality in both groups of young and aged mice compared to each age-matched control group. In conclusion, THSG can delay aging-related menopause, and the antioxidant properties of THSG may make it suitable for preventing aging-induced infertility.

3.
Sci Rep ; 12(1): 13352, 2022 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-35922458

RESUMO

Climate change has caused severe impacts on ecosystems and biodiversity globally, especially to vulnerable mountain ecosystems; the summits bear the brunt of such effects. Therefore, six summits in Taiwan were monitored based on a standardized multi-summit approach. We used both statistical downscaling of climate data and vegetation cover data to calculate climate niches to assess the impacts of climate change. Two indicators, thermophilic and moist-philic, were applied to evaluate the overall response of vegetation dynamics. The results revealed that potential evapotranspiration increased significantly and led to a declining tendency in monthly water balance from 2014 to 2019. The general pattern of species richness was a decline. The difference in plant cover among the three surveys showed an inconsistent pattern, although some dominant species expanded, such as the dwarf bamboo Yushania niitakayamensis. The thermophilic indicator showed that species composition had changed so that there were more thermophilic species at the three lowest summits. The moist-philization indicator showed a decline of humid-preferred species in the latest monitoring period. Although total precipitation did not decrease, our results suggest that the variability in precipitation with increased temperature and potential evapotranspiration altered alpine vegetation composition and could endanger vulnerable species in the future.


Assuntos
Mudança Climática , Ecossistema , Altitude , Biodiversidade , Plantas
4.
J Hand Surg Asian Pac Vol ; 27(4): 649-655, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35965359

RESUMO

Background: Ultrasonography is often used in the diagnosis of carpal tunnel syndrome (CTS). However, we were unable to find normative data regarding the cross-sectional area (CSA) of the median nerve in the Singapore population as measured by ultrasound. The aims of this study were to establish normative values of the CSA of the median nerve at the carpal tunnel inlet in a healthy population, 5 cm proximal to the carpal tunnel inlet, and to determine if the CSA correlated with side, age, gender or race. Methods: Sixty-nine wrists of 36 healthy subjects with no history of wrist injury or any signs and symptoms of CTS were examined. The CSA of the median nerve at the carpal tunnel inlet and 5 cm proximal to the carpal tunnel inlet was determined using ultrasound by a trained operator. Results: The mean CSA of the median nerve at the carpal tunnel inlet was 6.41 mm2 (SD 2.18 mm2). These were not significantly different from the values for mean CSA obtained 5 cm proximal to the carpal tunnel inlet. We did not find any correlation between the CSA of the median nerve and age, gender or race. Conclusions: The mean CSA of the median nerve at the carpal tunnel inlet in normal subjects in Singapore was found to be lower than other Asian populations. Wide variations of the median nerve CSA at the carpal tunnel inlet exists in the literature, and this is probably due to the heterogeneity of the study methodology and population. Level of Evidence: Level III (Diagnostic).


Assuntos
Síndrome do Túnel Carpal , Nervo Mediano , Baías , Síndrome do Túnel Carpal/diagnóstico por imagem , Antebraço/diagnóstico por imagem , Humanos , Nervo Mediano/diagnóstico por imagem , Singapura
5.
Biomed Chromatogr ; 35(12): e5227, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34388856

RESUMO

The aim of this study was to investigate drug interactions of L-dopa/carbidopa with catechin and green tea essence in rabbits following the simultaneous administration via an intramuscular injection of catechin or via an intragastric route for green tea essence with L-dopa/carbidopa. The results indicated that catechin at doses of 10, 20 and 50 mg/kg increased the area under the plasma concentration-time curve from time zero to the time of the last quantifiable concentration (AUC0-t ) of L-dopa by about 69, 78 and 42%, respectively. The metabolic ratios of the AUC0-t for 3-O-methyldopa (3-OMD)/L-dopa significantly decreased by about 56, 68 and 76% (P < 0.05), respectively. In addition, a single dose of 5/1.25 mg/kg L-dopa/carbidopa was co-administrated with 150 mg/kg green tea essence via an intragastric route with an oral-gastric tube. Comparing the related pharmacokinetic parameters of L-dopa, the clearance and metabolic ratio of L-dopa decreased by 20 and 19% (P < 0.05), respectively. In conclusion, catechin and green tea essence can significantly affect the metabolism of L-dopa by the catechol-O-methyltransferase (COMT) metabolic pathway. Catechin can enhance L-dopa bioavailability, and both catechin and green tea essence decreased 3-OMD formation. Therefore, catechin and green tea essence may increase L-dopa efficacy for Parkinson's disease treatment.


Assuntos
Catequina , Interações Ervas-Drogas , Levodopa , Chá/química , Animais , Disponibilidade Biológica , Carbidopa/sangue , Carbidopa/química , Carbidopa/farmacocinética , Catequina/metabolismo , Catequina/farmacocinética , Catecol O-Metiltransferase , Cromatografia Líquida , Levodopa/sangue , Levodopa/química , Levodopa/farmacocinética , Masculino , Coelhos , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Tirosina/análogos & derivados , Tirosina/sangue , Tirosina/química , Tirosina/farmacocinética
6.
Phytochemistry ; 187: 112776, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33933828

RESUMO

Transformation of 15-ene steviol (ent-13-hydroxy-kaur-15-en-19-oic acid) by growth cultures of Aspergillus niger BCRC 32720, Cunninghamella bainieri ATCC 9244, and Mortierella isabellina ATCC 38063 was conducted to generate various derivatives for the development of bioactive compounds. Four previously undescribed compounds along with six known compounds were obtained. The newly identified isolates were characterized using 1D and 2D NMR, IR, and HRESIMS, and three compounds were further confirmed by X-ray crystallographic analyses. Subsequently, the effects of 15-ene steviol and its derivatives on lipopolysaccharide (LPS)-induced cytokine production by THP-1 cells were examined, with dexamethasone used as a positive control. Results indicated that most of the tested compounds showed lower inhibitory effects than those detected in the dexamethasone-treated group, except that 15-ene steviol showed better effects than dexamethasone on the reduction of LPS-induced monocyte chemoattractant protein (MCP)-1, -2, and -3 release. Three specialized products similarly showed better effects than dexamethasone on the inhibition of LPS-induced secretion of regulated on activation, normal T cell expressed and secreted (RANTES). Moreover, none of the tested compounds showed any cytotoxicity or triggered cell apoptosis, and none affected the protein integrity of toll-like receptor 4 (TLR4) or MyD88, suggesting that these compounds may exert the anti-inflammatory activity downstream of membrane-associated TLR4 and MyD88 molecules.


Assuntos
Cunninghamella , Aspergillus niger , Diterpenos do Tipo Caurano , Fungos
7.
J Plant Res ; 134(1): 55-76, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33251557

RESUMO

Microsoroideae is the third largest of the six subfamilies of Polypodiaceae, containing over 180 species. These ferns are widely distributed in the tropical and subtropical regions of the Old World and Oceania. We documented the spore ornamentation and integrated these data into the latest phylogenetic hypotheses, including a sampling of 100 taxa representing each of 17 major lineages of microsoroid ferns. This enabled us to reconstruct the ancestral states of the spore morphology. The results show verrucate ornamentation as an ancestral state for Goniophlebieae and Lecanoptereae, globular for Microsoreae, and rugulate surface for Lepisoreae. In addition, spore ornamentation can be used to distinguish certain clades of the microsoroid ferns. Among all five tribes, Lecanoptereae show most diversity in spore surface ornamentation.


Assuntos
Gleiquênias , Polypodiaceae , Gleiquênias/genética , Filogenia , Esporos
8.
Int J Mol Sci ; 21(8)2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32326308

RESUMO

Hormones and their receptors play an important role in the development and progression of breast cancer. Hormones regulate the proliferation of breast cancer cells through binding between estrogen or progestins and steroid receptors that may reside in the cytoplasm or be transcriptionally activated as steroid-protein nuclear receptor complexes. However, receptors for nonpeptide hormones also exist in the plasma membrane. Via those receptors, hormones are able to stimulate breast cancer cell proliferation when activated. Integrins are heterodimeric structural proteins of the plasma membrane. Their primary functions are to interact with extracellular matrix proteins and growth factors. Recently, integrin αvß3 has been identified as a receptor for nonpeptide hormones, such as thyroid hormone and dihydrotestosterone (DHT). DHT promotes the proliferation of human breast cancer cells through binding to integrin αvß3. A receptor for resveratrol, a polyphenol stilbene, also exists on this integrin in breast cancer cells, mediating the anti-proliferative, pro-apoptotic action of the compound in these cells. Unrelated activities of DHT and resveratrol that originate at integrin depend upon downstream stimulation of mitogen-activated protein kinase (MAPK, ERK1/2) activity, suggesting the existence of distinct, function-specific pools of ERK1/2 within the cell. This review will discuss the features of these receptors in breast cancer cells, in turn suggesting clinical applications that are based on the interactions of resveratrol/DHT with integrin αvß3 and other androgen receptors.


Assuntos
Di-Hidrotestosterona/metabolismo , Integrina alfaVbeta3/metabolismo , Resveratrol/farmacologia , Androgênios/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Di-Hidrotestosterona/farmacologia , Humanos , Ligação Proteica , Receptores Androgênicos/metabolismo , Transdução de Sinais/efeitos dos fármacos
9.
Food Chem Toxicol ; 136: 111092, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31883986

RESUMO

Nano-diamino-tetrac (NDAT), a tetraiodothyroxine deaminated nano-particulated analog, has shown to inhibit expression of pro-inflammatory genes. NDAT inhibits expression of programmed death-ligand 1 (PD-L1). On the other hand, in addition to inhibiting inflammatory effect, the stilbene, resveratrol induces expression of cyclooxygenase-2 (COX-2) and its accumulation. Sequentially, inducible COX-2 complexes with p53 and induces p53-dependent anti-proliferation. In current study, we investigated mechanisms involved in combined treatment of NDAT and resveratrol on anti-proliferation in human oral cancer cells. Both resveratrol and NDAT inhibited expression of pro-inflammatory IL-1ß and TNF-α. They also inhibited expression of CCND1 and PD-L1. Both resveratrol and NDAT induced BAD expression but only resveratrol induced COX-2 expression in both OEC-M1 and SCC-25 cells. Combined treatment attenuated gene expression significantly compared with resveratrol treatment in both cancer cell lines. Resveratrol reduced nuclear PD-L1 accumulation which was enhanced by a STAT3 inhibitor, S31-201 or NDAT suggesting that NDAT may inactivate STAT3 to inhibit PD-L1 accumulation. In the presence of T4, NDAT further enhanced resveratrol-induced anti-proliferation in both cancer cell lines. These findings provide a novel understanding of the inhibition of NDAT in thyroxine-induced pro-inflammatory effect on resveratrol-induced anticancer properties.


Assuntos
Neoplasias Bucais/fisiopatologia , Poliglactina 910/farmacologia , Resveratrol/farmacologia , Tiroxina/análogos & derivados , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclina D1/genética , Ciclina D1/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/imunologia , Sinergismo Farmacológico , Expressão Gênica , Humanos , Neoplasias Bucais/genética , Neoplasias Bucais/imunologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/imunologia , Tiroxina/farmacologia
10.
PhytoKeys ; 131: 69-81, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31565025

RESUMO

A new species of Bolbitis, B. lianhuachihensis sp. nov., was found in central Taiwan. It most resembles B. virens var. compacta and B. hainanensis. A phylogenetic tree of Taiwanese and other Asian species of Bolbitis species supports the recognition of the new species. Morphologically, the combination of anastomosing venation and fewer sterile pinnae are critical characters to discriminate B. lianhuachihensis from other Taiwanese Bolbitis species. Bolbitis lianhuachihensis can be further distinguished from B. virens var. compacta and B. hainanensis by having lanceolate sterile pinnae and absent or fewer free veinlets in small areoles of sterile pinnae. The morphological descriptions, illustration, ecology and distribution of the new species are presented. A key to all Taiwanese Bolbitis is also provided.

11.
Food Chem Toxicol ; 133: 110808, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499123

RESUMO

The obesity-regulated gene, leptin, is essential for diet. Leptin resistance causes obesity and related diseases. Certain types of diet are able to decrease leptin resistance. However, leptin has been shown to be correlated with inflammation and stimulate proliferation of various cancers. Two synthetic leptin derivatives (mimetics), OB3 and [D-Leu-4]-OB3, show more effective than leptin in reducing obesity and diabetes in mouse models. OB3 inhibits leptin-induced proliferation in ovarian cancer cells. However, effects of these mimetics in hepatocellular carcinoma (HCC) have not been investigated. In the present study, we examined the effects of OB3 and [D-Leu-4]-OB3 on cell proliferation and gene expressions in human HCC cell cultures. In contrast to what was reported for leptin, OB3 and [D-Leu-4]-OB3 reduced cell proliferation in hepatomas. Both OB3 and [D-Leu-4]-OB3 stimulated expression of pro-apoptotic genes. Both compounds also inhibited expressions of pro-inflammatory, proliferative and metastatic genes and PD-L1 expression. In combination with leptin, OB3 inhibited leptin-induced cell proliferation and expressions of pro-inflammation-, and proliferation-related genes. Furthermore, the OB3 peptide inhibited phosphoinositide 3-kinase (PI3K) activation which is essential for leptin-induced proliferation in HCC. These results indicate that OB3 and [D-Leu-4]-OB3 may have the potential to reduce leptin-related inflammation and proliferation in HCC cells.


Assuntos
Proliferação de Células/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Leptina/farmacologia , Fragmentos de Peptídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular Tumoral , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fosfatidilinositol 3-Quinase/metabolismo , Inibidores de Proteínas Quinases/farmacologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-30915033

RESUMO

Colorectal cancer is a serious medical problem in Taiwan. New, effective therapeutic approaches are needed. The selection of promising anticancer drugs and the transition from pre-clinical investigations to clinical trials are often challenging. The deaminated thyroid hormone analog (tetraiodothyroacetic acid, tetrac) and its nanoparticulate analog (NDAT) have been shown to have anti-proliferative activity in vitro and in xenograft model of different neoplasms, including colorectal cancers. However, mechanisms involved in tetrac- and NDAT-induced anti-proliferation in colorectal cancers are incompletely understood. We have investigated possible mechanisms of tetrac and NDAT action in colorectal cancer cells, using a perfusion bellows cell culture system that allows efficient, large-scale screening for mechanisms of drug actions on tumor cells. Although integrin αvß3 in K-RAS wild type colorectal cancer HT-29 cells was far less than that in K-RAS mutant HCT116 cells, HT-29 was more sensitive to both tetrac and NDAT. Results also indicate that both tetrac and NDAT bind to tumor cell surface integrin αvß3, and the agents may have different mechanisms of anti-proliferation in colorectal cancer cells. K-RAS status appears to play an important role in drug resistance that may be encountered in treatment with this drug combination.

14.
Mar Drugs ; 16(12)2018 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-30563284

RESUMO

A marine sesterterpenoid-type natural product, heteronemin, retains anticancer effects. In the current study, we investigate the antitumor mechanism of heteronemin in cholangiocarcinoma cells and further explore its molecular targets. Initially, heteronemin exhibited potent cytotoxic effects against cholangiocarcinoma HuccT1 and SSP-25 cells. In vitro, heteronemin altered the abilities of cell adhesion and cell migration in HuccT1 and SSP-25 cell lines. It repressed messenger ribonucleic acid (mRNA) expression levels of transforming growth factor (TGF)-ß, mothers against decapentaplegic homolog (SMAD) and Myc, whose protein products play important roles in regulating cell growth, angiogenesis, and metastasis. In addition, heteronemin altered several signaling pathways. The results indicate that heteronemin was able to modulate cell adhesion, the expression of extracellular matrix (ECM) receptors, the TGF-ß pathway, cell motility, the membrane integration, metastasis response, matrix metalloproteinase (MMP) remodeling, the regulation of metabolism, sprouting angiogenesis, transcription factors, and vasculogenesis in cholangiocarcinoma cell lines. The results also suggest that it activated multiple signal transduction pathways to induce an anti-proliferation effect and anti-metastasis in cholangiocarcinoma. In conclusion, heteronemin may be used as a potential medicine for anticancer therapy.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias dos Ductos Biliares/tratamento farmacológico , Colangiocarcinoma/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Terpenos/farmacologia , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Poríferos/química , RNA Mensageiro/metabolismo , Terpenos/uso terapêutico , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
15.
Front Pharmacol ; 9: 807, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30116189

RESUMO

Traditional herb medicine, golden thread (Anoectochilus formosanus Hayata) has been used to treat various diseases. Hyperglycemia induces generation of reactive oxygen species (ROS) and enhancement of oxidative stress which are risk factors for cancer progression and metastasis. In this study, we evaluated hypoglycemic effect of A. formosanus extracts (AFEs) in an inducible hyperglycemia animal model and its capacity of free-radical scavenging to establish hyperglycemia-related carcinogenesis. AFE reduced blood glucose in hyperglycemic mice while there was no change in control group. The incremental area under blood glucose response curve was decreased significantly in hyperglycemic mice treated with AFE in a dose-dependent manner. AFE and metformin at the same administrated dose of 50 mg/kg showed similar effect on intraperitoneal glucose tolerance test in hyperglycemic mice. Free-radical scavenger capacity of AFE was concentration dependent and 200 µg/ml of AFE was able to reduce more than 41% of the free radical. Treatment of cancer cells with AFE inhibited constitutive PD-L1 expression and its protein accumulation. It also induced expression of pro-apoptotic genes but inhibited proliferative and metastatic genes. In addition, it induced anti-proliferation in cancer cells. The results suggested that AFE not only reduced blood glucose concentration as metformin but also showed its potential use in cancer immune chemoprevention/therapy via hypoglycemic effect, ROS scavenging and PD-L1 suppression.

16.
Horm Cancer ; 9(5): 349-360, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30027502

RESUMO

Cancer resistance to chemotherapeutic agents is a major issue in the management of cancer patients. Overexpression of the ribonucleotide reductase regulatory subunit M2 (RRM2) has been associated with aggressive cancer behavior and chemoresistance. Nano-diamino-tetrac (NDAT) is a nanoparticulate derivative of tetraiodothyroacetic acid (tetrac), which exerts anticancer properties via several mechanisms and downregulates RRM2 gene expression in cancer cells. Resveratrol is a stilbenoid phytoalexin which binds to a specific site on the cell surface integrin αvß3 to trigger cancer cell death via nuclear translocation of COX-2. Here we report that resveratrol paradoxically activates RRM2 gene expression and protein translation in colon cancer cells. This unanticipated effect inhibits resveratrol-induced COX-2 nuclear accumulation. RRM2 downregulation, whether achieved by RNA interference or treatment with NDAT, enhanced resveratrol-induced COX-2 gene expression and nuclear uptake which is essential to integrin αvß3-mediated-resveratrol-induced antiproliferation in cancer cells. Elsewhere, NDAT downregulated resveratrol-induced RRM2 expression in vivo but potentiated the anticancer effect of the stilbene. These findings suggest that RRM2 appears as a cancer cell defense mechanism which can hinder the anticancer effect of the stilbene via the integrin αvß3 axis. Furthermore, the antagonistic effect of RRM2 against resveratrol is counteracted by the administration of NDAT.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Neoplasias Colorretais/genética , Poliglactina 910/uso terapêutico , Resveratrol/uso terapêutico , Tiroxina/análogos & derivados , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Nus , Poliglactina 910/farmacologia , Resveratrol/farmacologia , Tiroxina/farmacologia , Tiroxina/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Food Chem Toxicol ; 120: 346-355, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30026090

RESUMO

Leiomyomas (myomas) are the most common benign smooth muscle cell tumor of the myometrium. Resveratrol, a stilbene, has been used as an anti-inflammatory and antitumor agent. In the current study, we investigated the inhibitory effect of resveratrol on the proliferation of primary human myoma cell cultures. Resveratrol arrested cell proliferation via integrin αvß3. It also inhibited integrin αvß3 expression and protein accumulation. Concurrently, constitutive AKT phosphorylation in myoma cells was inhibited by resveratrol. Expressions of proapoptotic genes, such as cyclooxygenase (COX)-2, p21 and CDKN2, were induced by resveratrol in myoma cells. On the other hand, expressions of proliferative (anti-apoptotic) genes were either inhibited, as in BCL2, or unchanged, as in cyclin D1 and proliferating cell nuclear antigen (PCNA). The accumulation of insulin-like growth factor (IGF)-1 receptor (IGF-1R) was inhibited by resveratrol in primary myoma cells. IGF-1-induced cell proliferation was inhibited by co-incubation with resveratrol. Therefore, growth modulation of myoma cells occurs via mechanisms dependent on cross-talk between integrin αvß3 and IGF-1R. Our findings suggest that resveratrol can be considered an alternative therapeutic agent for myomas.


Assuntos
Proliferação de Células/efeitos dos fármacos , Integrina alfaVbeta3/metabolismo , Leiomioma/patologia , Receptor Cross-Talk , Receptor IGF Tipo 1/metabolismo , Estilbenos/farmacologia , Neoplasias Uterinas/patologia , Feminino , Citometria de Fluxo , Humanos , Marcação In Situ das Extremidades Cortadas , Leiomioma/metabolismo , Fosforilação , Resveratrol , Neoplasias Uterinas/metabolismo
18.
Food Chem Toxicol ; 120: 1-11, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29960019

RESUMO

Programmed death-ligand 1 (PD-L1) is a critical regulator to defend tumor cells against immune surveillance. Thyroid hormone has been shown to induce PD-L1 expression in cancer cells. Its nano-particulated analogue, nano-diamino-tetrac (NDAT; Nanotetrac) is an anticancer/anti-angiogenic agent. In the current study, the inhibitory mechanism by which NDAT inhibited PD-L1 mRNA abundance and PD-L1 protein content in oral cancer cells was investigated. NDAT inhibited inducible PD-L1 expression and protein accumulation by the inhibition of activated ERK1/2 and PI3K. Knockdown PD-L1 also inhibited the proliferation of oral cancer cells which suggests that the inhibitory effect of NDAT on PD-L1 expression maybe is one of the critical mechanisms for NDAT-induced anti-proliferative effect in oral cancer cells.


Assuntos
Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/genética , Carcinoma de Células Escamosas/patologia , Proliferação de Células/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Neoplasias Bucais/patologia , Nanopartículas , Tiroxina/análogos & derivados , Antineoplásicos/farmacologia , Antígeno B7-H1/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neoplasias Bucais/genética , Neoplasias Bucais/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/farmacologia , RNA Mensageiro/metabolismo , Tiroxina/farmacologia
19.
Endocr Relat Cancer ; 25(5): 533-545, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29555649

RESUMO

Thyroid hormone, l-thyroxine (T4), has been shown to promote ovarian cancer cell proliferation via a receptor on plasma membrane integrin αvß3 and to induce the activation of ERK1/2 and expression of programmed death-ligand 1 (PD-L1) in cancer cells. In contrast, resveratrol binds to integrin αvß3 at a discrete site and induces p53-dependent antiproliferation in malignant neoplastic cells. The mechanism of resveratrol action requires nuclear accumulation of inducible cyclooxygenase (COX)-2 and its complexation with phosphorylated ERK1/2. In this study, we examined the mechanism by which T4 impairs resveratrol-induced antiproliferation in human ovarian cancer cells and found that T4 inhibited resveratrol-induced nuclear accumulation of COX-2. Furthermore, T4 increased expression and cytoplasmic accumulation of PD-L1, which in turn acted to retain inducible COX-2 in the cytoplasm. Knockdown of PD-L1 by small hairpin RNA (shRNA) relieved the inhibitory effect of T4 on resveratrol-induced nuclear accumulation of COX-2- and COX-2/p53-dependent gene expression. Thus, T4 inhibits COX-2-dependent apoptosis in ovarian cancer cells by retaining inducible COX-2 with PD-L1 in the cytoplasm. These findings provide new insights into the antagonizing effect of T4 on resveratrol's anticancer properties.


Assuntos
Apoptose/efeitos dos fármacos , Antígeno B7-H1/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Resveratrol/metabolismo , Tiroxina/uso terapêutico , Feminino , Humanos , Neoplasias Ovarianas/patologia , Tiroxina/farmacologia , Transfecção
20.
Food Chem Toxicol ; 112: 67-75, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29242151

RESUMO

Cyclooxygenase (COX)-2 has been implicated in cancer development. However, resveratrol-induced nuclear accumulation of COX-2 enhances p53-dependent anti-proliferation in different types of cancers. Treatment with resveratrol leads to phosphorylation and nuclear translocation of mitogen-activated protein kinase (ERK1/2), and accumulation of nuclear COX-2 to complex with pERK1/2 and p53. The consequence is Ser-15 phosphorylation of p53 (pSer15-p53), and induction of anti-proliferation in cancer cells. We investigated the mechanisms by which resveratrol-inducible COX-2 facilitates p53-dependent anti-proliferation in prostate cancer LNCaP cells. Resveratrol treatment caused nuclear accumulation and complexing of ERK1/2, pSer15-p53 and COX-2 which was activated ERK1/2-dependent. Knockdown of SUMO-1 by shRNA also reduced nuclear accumulation of COX-2. Inhibition of nuclear accumulation by the COX-2 specific inhibitor, NS-398, inhibited co-localization of nuclear COX-2 and SUMO-1. Similar results were observed in the PD98059-treated cells. Finally, inhibition of SUMO-1 expression also reduced resveratrol-induced expression of pro-apoptotic genes but increased the expression of proliferative genes. In summary, these results demonstrate that inducible COX-2 associates with phosphorylated ERK1/2 to induce the phosphorylation of Ser-15 in p53 and then complexes with p53 and SUMO-1 which binds to p53-responsive pro-apoptotic genes to enhance their expression. The inhibition of COX-2 expression and activity significantly blocks the pro-apoptotic effect of resveratrol.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Neoplasias da Próstata/patologia , Estilbenos/farmacologia , Sumoilação , Apoptose/genética , Western Blotting , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Ciclo-Oxigenase 2/biossíntese , Indução Enzimática , Técnicas de Silenciamento de Genes , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Microscopia Confocal , Fosforilação , Neoplasias da Próstata/enzimologia , Transporte Proteico , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Resveratrol , Proteína SUMO-1/genética , Proteína SUMO-1/metabolismo , Proteína Supressora de Tumor p53/metabolismo
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