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1.
Nutrients ; 15(21)2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37960146

RESUMEN

Prostate cancer (PC) is the second most frequently diagnosed cancer and the fifth leading cause of cancer-related death in males worldwide. Early-stage PC patients can benefit from surgical, radiation, and hormonal therapies; however, once the tumor transitions to an androgen-refractory state, the efficacy of treatments diminishes considerably. Recently, the exploration of natural products, particularly dietary phytochemicals, has intensified in response to addressing this prevailing medical challenge. In this study, we uncovered a synergistic effect from combinatorial treatment with lovastatin (an active component in red yeast rice) and Antrodia camphorata (AC, a folk mushroom) extract against PC3 human androgen-refractory PC cells. This combinatorial modality resulted in cell cycle arrest at the G0/G1 phase and induced apoptosis, accompanied by a marked reduction in molecules responsible for cellular proliferation (p-Rb/Rb, Cyclin A, Cyclin D1, and CDK1), aggressiveness (AXL, p-AKT, and survivin), and stemness (SIRT1, Notch1, and c-Myc). In contrast, treatment with either AC or lovastatin alone only exerted limited impacts on the cell cycle, apoptosis, and the aforementioned signaling molecules. Notably, significant reductions in canonical PC stemness markers (CD44 and CD133) were observed in lovastatin/AC-treated PC3 cells. Furthermore, lovastatin and AC have been individually examined for their anti-PC properties. Our findings elucidate a pioneering discovery in the synergistic combinatorial efficacy of AC and clinically viable concentrations of lovastatin on PC3 PC cells, offering novel insights into improving the therapeutic effects of dietary natural products for future strategic design of therapeutics against androgen-refractory prostate cancer.


Asunto(s)
Productos Biológicos , Neoplasias de la Próstata , Masculino , Humanos , Andrógenos/metabolismo , Células PC-3 , Lovastatina/farmacología , Proliferación Celular , Apoptosis , Neoplasias de la Próstata/patología , Productos Biológicos/farmacología , Productos Biológicos/uso terapéutico , Línea Celular Tumoral
2.
Mar Drugs ; 17(9)2019 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-31500384

RESUMEN

Malignant glioma (MG) is a poor prognostic brain tumor with inevitable recurrence after multimodality treatment. Searching for more effective treatment is urgently needed. Differentiation induction via epigenetic modification has been proposed as a potential anticancer strategy. Natural products are known as fruitful sources of epigenetic modifiers with wide safety margins. We thus explored the effects of oligo-fucoidan (OF) from brown seaweed on this notion in MG cells including Grade III U87MG cells and Grade IV glioblastoma multiforme (GBM)8401 cells and compared to the immortalized astrocyte SVGp12 cells. The results showed that OF markedly suppress the proliferation of MG cells and only slightly affected that of SVGp12 cells. OF inhibited the protein expressions of DNA methyltransferases 1, 3A and 3B (DNMT1, 3A and 3B) accompanied with obvious mRNA induction of differentiation markers (MBP, OLIG2, S100ß, GFAP, NeuN and MAP2) both in U87MG and GBM8401 cells. Accordingly, the methylation of p21, a DNMT3B target gene, was decreased by OF. In combination with the clinical DNMT inhibitor decitabine, OF could synergize the growth inhibition and MBP induction in U87MG cells. Appropriated clinical trials are warranted to evaluate this potential complementary approach for MG therapy after confirmation of the effects in vivo.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Diferenciación Celular/efectos de los fármacos , Epigénesis Genética/efectos de los fármacos , Glioma/tratamiento farmacológico , Polisacáridos/farmacología , Antineoplásicos/farmacología , Biomarcadores de Tumor/genética , Neoplasias Encefálicas/genética , Diferenciación Celular/genética , Línea Celular Tumoral , Epigénesis Genética/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/genética , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glioma/genética , Humanos , Recurrencia Local de Neoplasia/tratamiento farmacológico
3.
Artículo en Inglés | MEDLINE | ID: mdl-27525019

RESUMEN

The Chinese herbal mixture, Tien-Hsien Liquid (THL), has been proven to suppress the growth and invasiveness of cancer cells and is currently regarded as a complementary medicine for the treatment of cancer. Our previous study using acute promyelocytic leukemia cells uncovered its effect on the downregulation of DNA methyltransferase 1 (DNMT1) which is often overexpressed in cancer cells resulting in the repression of tumor suppressors via hypermethylation. Herein, we explored the effects of THL in MCF-7 breast cancer cells that also demonstrate elevated DNMT1. The results show that THL dose-dependently downregulated DNMT1 accompanied by the induction of tumor suppressors such as p21 and p15. THL arrested cell cycle in G2/M phase and decreased the protein levels of cyclin A, cyclin B1, phospho-pRb, and AKT. DNMT1 inhibition was previously reported to exert a radiosensitizing effect in cancer cells through the repression of DNA repair. We found that THL enhanced radiation-induced clonogenic cell death in MCF-7 cells and decreased the level of DNA double-strand break repair protein, Rad51. Our observations may be the result of DNMT1 downregulation. Due to the fact that DNMT1 inhibition is now a mainstream strategy for anticancer therapy, further clinical trials of THL to confirm its clinical efficacy are warranted.

4.
Artículo en Inglés | MEDLINE | ID: mdl-28074102

RESUMEN

Lung cancer is the leading cause of cancer death worldwide; the most common pathologic type is lung adenocarcinoma (LADC). In spite of the recent progress in targeted therapy, most LADC patients eventually expired due to the inevitable recurrence and drug resistance. New complementary agent with evidence-based molecular mechanism is urgently needed. MiR-34a is an important p53 downstream tumor suppressor, which regulates apoptosis, cell-cycle, EMT (epithelial mesenchymal transition), and so forth. Its expression is deficient in many types of cancers including LADC. Here, we show that a Chinese herbal formula JP-1 activates p53/miR-34a axis in A549 human LADC cells (p53 wild-type). Treatment with JP-1 induces p53 and its downstream p21 and BAX proteins as well as the miR-34a, resulting in growth inhibition, colony formation reduction, migration repression, and apoptosis induction. Accordingly, the decreases of miR-34a downstream targets such as CDK6, SIRT1, c-Myc, survivin, Snail, and AXL were observed. Moreover, JP-1 activates AMPKα and reduces mTOR activity, implying its inhibitory effect on the energy-sensitive protein synthesis and cell proliferation signaling. Our results show that JP-1 activates p53/miR-34a tumor suppressor axis and decreases proteins related to proliferation, apoptosis resistance, and metastasis, suggesting its potential as a complementary medicine for LADC treatment.

5.
Mech Dev ; 129(9-12): 324-38, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22691402

RESUMEN

Williams Syndrome Transcription Factor (WSTF) is one of ∼25 haplodeficient genes in patients with the complex developmental disorder Williams Syndrome (WS). WS results in visual/spatial processing defects, cognitive impairment, unique behavioral phenotypes, characteristic "elfin" facial features, low muscle tone and heart defects. WSTF exists in several chromatin remodeling complexes and has roles in transcription, replication, and repair. Chromatin remodeling is essential during embryogenesis, but WSTF's role in vertebrate development is poorly characterized. To investigate the developmental role of WSTF, we knocked down WSTF in Xenopus laevis embryos using a morpholino that targets WSTF mRNA. BMP4 shows markedly increased and spatially aberrant expression in WSTF-deficient embryos, while SHH, MRF4, PAX2, EPHA4 and SOX2 expression are severely reduced, coupled with defects in a number of developing embryonic structures and organs. WSTF-deficient embryos display defects in anterior neural development. Induction of the neural crest, measured by expression of the neural crest-specific genes SNAIL and SLUG, is unaffected by WSTF depletion. However, at subsequent stages WSTF knockdown results in a severe defect in neural crest migration and/or maintenance. Consistent with a maintenance defect, WSTF knockdowns display a specific pattern of increased apoptosis at the tailbud stage in regions corresponding to the path of cranial neural crest migration. Our work is the first to describe a role for WSTF in proper neural crest function, and suggests that neural crest defects resulting from WSTF haploinsufficiency may be a major contributor to the pathoembryology of WS.


Asunto(s)
Cresta Neural/fisiología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Xenopus/genética , Proteínas de Xenopus/metabolismo , Xenopus laevis/embriología , Animales , Apoptosis/genética , Secuencia de Bases , Tipificación del Cuerpo/genética , Movimiento Celular/genética , Desarrollo Embrionario/genética , Femenino , Técnicas de Silenciamiento del Gen/métodos , Humanos , Datos de Secuencia Molecular , Cresta Neural/crecimiento & desarrollo , Cresta Neural/metabolismo , Síndrome de Williams/genética , Síndrome de Williams/metabolismo
6.
Asia Pac J Clin Nutr ; 18(3): 423-32, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19786391

RESUMEN

BACKGROUND: A clinical significant improvement in health-related quality of life (HRQOL) is one of the main goals of weight control. OBJECTIVE: To reveal the extent of weight loss on changes of HRQOL in obese Chinese. DESIGN: A total of 119 motivated obese adults (BMI: 33.5 +/- 0.4 kg/m2) completed a 6-month weight loss intervention program by following either low calorie diet suggestions (LCDS; n=18), LCDS plus sibutramine (SG; n=27), LCDS plus orlistat (OG; n=41), or very low calorie diet (VLCD; n=33). Changes in body composition (TBF-410GS, Tanita Co., Tokyo, Japan) and HRQOL (36-item Short-Form (SF-36) questionnaire) were measured accordingly. RESULTS: After 6-months, the greatest weight loss (p<0.001) was found in VLCD group (14.1 +/- 1.2 kg, 15.1%), followed by OG (10.6 +/- 0.9 kg, 11.5%), SG (9.6 +/- 1.3 kg, 10.2%) and LCDS alone (8.7 +/- 1.2 kg, 11.1%). The physical component score of SF-36 were significantly improved at 6-month follow-up (p<0.001), but not the mental component score. Improvements in general health score of SF-36 (Gamma mean: 6.1 +/- 2.8, p<0.05) were greater in females than males. Subjects with weight loss > or = 15 % had the greatest improvements in SF-36 scores whereas no changes in SF-36 scores were found with weight loss < 5%. CONCLUSIONS: The extent, not the type of intervention, of weight loss is highly correlated with the favorable changes in HRQOL at 6-months. Weight loss above 5% of baseline values is necessary to show significant improvements in HRQOL in motivated obese Chinese.


Asunto(s)
Estado de Salud , Motivación , Obesidad/terapia , Calidad de Vida/psicología , Pérdida de Peso/fisiología , Adolescente , Adulto , Fármacos Antiobesidad/uso terapéutico , Depresores del Apetito/uso terapéutico , Terapia Combinada , Ciclobutanos/uso terapéutico , Dieta Reductora , Femenino , Humanos , Lactonas/uso terapéutico , Masculino , Persona de Mediana Edad , Obesidad/psicología , Orlistat , Caracteres Sexuales , Taiwán , Adulto Joven
7.
J Biol Chem ; 280(1): 104-11, 2005 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-15501826

RESUMEN

Copper is an essential cellular cofactor that becomes toxic at high levels. Copper homeostasis is tightly regulated by opposing mechanisms that control copper import, export, and copper binding capacity within the cell. High levels of copper induce the expression of metallothioneins, small sulfhydryl-rich proteins with high metal binding capabilities that serve as neutralizers of toxic levels of metals. In yeast, the CUP1 gene encodes a copper metallothionein that is strongly induced in response to metals and other stress and is subsequently rapidly down-regulated. Activation of CUP1 is mediated by the copper-responsive transcriptional activator AceI, and also requires the histone acetylase Spt10 for full induction. We have examined the role of histone H2A in the normal regulation of the CUP1 gene. We have shown that specific H2A mutations in combination with spt10 deletions result in aberrant regulation of CUP1 expression. Certain lysine mutations in H2A alleviate the transcriptional defect in spt10 Delta strains, though CUP1 activation is still delayed in these mutants; however, CUP1 shutdown is normal. In contrast, serine mutations in H2A prevent CUP1 shutdown when combined with spt10 deletions. In addition, swi/snf mutants exhibit both impaired CUP1 induction and failure to shut down CUP1 normally. Finally, different Spt10-dependent histone acetylation events correlate with induction and shutdown. Taken together, these data indicate that CUP1 transcriptional shutdown, like induction, is an active process controlled by the chromatin structure of the gene. These results provide new insights for the role of chromatin structure in metal homeostasis.


Asunto(s)
Histonas/genética , Homeostasis , Metalotioneína/genética , Proteínas de Saccharomyces cerevisiae/genética , Factores de Transcripción/genética , Proteínas Portadoras , Cobre/metabolismo , Regulación Fúngica de la Expresión Génica , Histona Acetiltransferasas , Histonas/metabolismo , Metalotioneína/metabolismo , Mutación , Regiones Promotoras Genéticas , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/metabolismo , Transcripción Genética
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