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1.
Front Oncol ; 12: 998346, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36147917

RESUMO

Anthocyanidins are the most abundant polyphenols in pomegranate juice. This class of molecules includes Delphinidin (Del), Cyanidin (Cya), and Pelargonidin (Pel). Using prostate, breast and pancreatic cancer cell lines PC3, MDA-MB-231, BxPC-3 and MiaPaCa-2, we show that anthocyanidins inhibit cell proliferation (measured by MTT assay) and induce apoptosis like cell death (measured by DNA/Histone ELISA). Copper chelator neocuproine and reactive oxygen species scavengers (thiourea for hydroxyl radical and superoxide dismutase for superoxide anion) significantly inhibit this reaction thus demonstrating that intracellular copper reacts with anthocyanidins in cancer cells to cause DNA damage via ROS generation. We further show that copper-supplemented media sensitizes normal breast epithelial cells (MCF-10A) to Del-mediated growth inhibition as determined by decreased cell proliferation. Copper supplementation results in increased expression of copper transporters Ctr1 and ATP7A in MCF-10A cells, which is attenuated by the addition of Del in the medium. We propose that the copper mediated, ROS-induced mechanism of selective cell death of cancer cells may in part explain the anticancer effects of anthocyanidins.

2.
Biomedicines ; 10(3)2022 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-35327466

RESUMO

The possible roles of elevated endogenous copper levels in malignant cells are becoming increasingly understood at a greater depth. Our laboratory has previously demonstrated that tea catechins have the ability to mobilize endogenous copper and undergo a Fenton-like reaction that can selectively damage cancer cells. In this communication, by using a diverse panel of malignant cell lines, we demonstrate that the ability of the catechin family [(-)-epigallocatechin-3-gallate (EGCG), (-)-epigallocatechin (EGC), (-)-epicatechin (EC), and (+)-catechin (C)] to induce apoptosis is dependent on their structure. We further confirm that reactive oxygen species (ROS) are the terminal effectors causing copper-mediated DNA damage. Our studies demonstrate the role of cellular copper transporters CTR1 and ATP7A in the survival dynamics of malignant cells post-EGCG exposure. The results, when considered together with our previous studies, highlight the critical role that copper dynamics and mobilization plays in cancer cells and paves the way for a better understanding of catechins as nutraceutical supplements for malignancies.

3.
Biol Futur ; 73(1): 55-69, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35040098

RESUMO

Discouraging statistics of cancer disease has projected an increase in the global cancer burden from 19.3 to 28.4 million incidences annually within the next two decades. Currently, there has been a revival of interest in nutraceuticals with evidence of pharmacological properties against human diseases including cancer. Diet is an integral part of lifestyle, and it has been proposed that an estimated one-third of human cancers can be prevented through appropriate lifestyle modification including dietary habits; hence, it is considered significant to explore the pharmacological benefits of these agents, which are easily accessible and have higher safety index. Accordingly, an impressive embodiment of evidence supports the concept that the dietary factors are critical modulators to prevent, retard, block, or reverse carcinogenesis. Such an action reflects the ability of these molecules to interfere with multitude of pathways to subdue and neutralize several oncogenic factors and thereby keep a restraint on neoplastic transformations. This review provides a series of experimental evidence based on the current literature to highlight the translational potential of nutraceuticals for the prevention of the disease through consumption of enriched diets and its efficacious management by means of novel interventions. Specifically, this review provides the current understanding of the chemopreventive pharmacology of nutraceuticals such as cucurbitacins, morin, fisetin, curcumin, luteolin and garcinol toward their potential as anticancer agents.


Assuntos
Suplementos Nutricionais , Neoplasias , Carcinogênese , Proliferação de Células , Quimioprevenção , Dieta , Humanos , Neoplasias/prevenção & controle
4.
Int J Mol Sci ; 20(4)2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30781783

RESUMO

Garcinol, a dietary factor obtained from Garcinia indica, modulates several key cellular signaling pathways as well as the expression of miRNAs. Acquired resistance to standard therapies, such as erlotinib and cisplatin, is a hallmark of non-small cell lung cancer (NSCLC) cells that often involves miRNA-regulated epithelial-to-mesenchymal transition (EMT). We used A549 cells that were exposed to transforming growth factor beta 1 (TGF-ß1), resulting in A549M cells with mesenchymal and drug resistant phenotype, and report that garcinol sensitized resistant cells with mesenchymal phenotype to erlotinib as well as cisplatin with significant decrease in their IC50 values. It also potentiated the apoptosis-inducing activity of erlotinib in A549M and the endogenously mesenchymal H1299 NSCLC cells. Further, garcinol significantly upregulated several key EMT-regulating miRNAs, such as miR-200b, miR-205, miR-218, and let-7c. Antagonizing miRNAs, through anti-miRNA transfections, attenuated the EMT-modulating activity of garcinol, as determined by mRNA expression of EMT markers, E-cadherin, vimentin, and Zinc Finger E-Box Binding Homeobox 1 (ZEB1). This further led to repression of erlotinib as well as cisplatin sensitization, thus establishing the mechanistic role of miRNAs, particularly miR-200c and let-7c, in garcinol-mediated reversal of EMT and the resulting sensitization of NSCLC cells to standard therapies.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MicroRNAs/genética , Terpenos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Cloridrato de Erlotinib/farmacologia , Humanos , Concentração Inibidora 50 , Neoplasias Pulmonares/tratamento farmacológico , MicroRNAs/metabolismo , Terpenos/química , Terpenos/uso terapêutico , Fator de Crescimento Transformador beta1/farmacologia
5.
Open Orthop J ; 11: 777-784, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28979590

RESUMO

More than 36 million people are living with human immunodeficiency virus (HIV) infection worldwide and 50% of them have access to antiretroviral therapy (ART). While recent advances in HIV therapy have reduced the viral load, restored CD4 T cell counts and decreased opportunistic infections, several bone-related abnormalities such as low bone mineral density (BMD), osteoporosis, osteopenia, osteomalacia and fractures have emerged in HIV-infected individuals. Of all classes of antiretroviral agents, HIV protease inhibitors used in ART combination showed a higher frequency of osteopenia, osteoporosis and low BMD in HIV-infected patients. Although the mechanisms of HIV and/or ART associated bone abnormalities are not known, it is believed that the damage is caused by a complex interaction of T lymphocytes with osteoclasts and osteoblasts, likely influenced by both HIV and ART. In addition, infection of osteoclasts and bone marrow stromal cells by HIV, including HIV Gp120 induced apoptosis of osteoblasts and release of proinflammatory cytokines have been implicated in impairment of bone development and maturation. Several of the newer antiretroviral agents currently used in ART combination, including the widely used tenofovir in different formulations show relative adverse effects on BMD. In this context, switching the HIV-regimen from tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide (TAF) showed improvement in BMD of HIV-infected patients. In addition, inclusion of integrase inhibitor in ART combination is associated with improved BMD in patients. Furthermore, supplementation of vitamin D and calcium with the initiation of ART may mitigate bone loss. Therefore, levels of vitamin D and calcium should be part of the evaluation of HIV-infected patients.

6.
Int J Mol Sci ; 18(10)2017 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-29036883

RESUMO

MicroRNA-34a (miR-34a) is a tumor suppressor that has attracted considerable attention in recent years. It modulates cancer cell invasion, metastasis, and drug resistance, and has also been evaluated as a diagnostic and/or prognostic biomarker. A number of targets of miR-34a have been identified, including some other non-coding RNAs, and it is believed that the modulation of these myriads of targets underlines the versatile role of miR-34a in cancer progression and pathogenesis. Seemingly appealing results from preclinical studies have advocated the testing of miR-34a in clinical trials. However, the results obtained are not very encouraging and there is a need to re-interpret how miR-34a behaves in a context dependent manner in different cancers. In this review, we have attempted to summarize the most recent evidence related to the regulation of different genes and non-coding RNAs by miR-34a and the advances in the field of nanotechnology for the targeted delivery of miR-34a-based therapeutics and mimics. With the emergence of data that contradicts miR-34a's tumor suppressive function, it is important to understand miR-34a's precise functioning, with the aim to establish its role in personalized medicine and to apply this knowledge for the identification of individual patients that are likely to benefit from miR-34a-based therapy.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias/genética , Interferência de RNA , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Ensaios Clínicos como Assunto , Avaliação Pré-Clínica de Medicamentos , Epistasia Genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Transferência de Genes , Terapia Genética/métodos , Humanos , MicroRNAs/administração & dosagem , Nanotecnologia/métodos , Neoplasias/patologia , Neoplasias/terapia , RNA Mensageiro/genética , Ativação Transcricional
7.
Molecules ; 22(3)2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-28273819

RESUMO

Phytochemicals are an important part of traditional medicine and have been investigated in detail for possible inclusion in modern medicine as well. These compounds often serve as the backbone for the synthesis of novel therapeutic agents. For many years, phytochemicals have demonstrated encouraging activity against various human cancer models in pre-clinical assays. Here, we discuss select phytochemicals-curcumin, epigallocatechin-3-gallate (EGCG), resveratrol, plumbagin and honokiol-in the context of their reported effects on the processes of inflammation and oxidative stress, which play a key role in tumorigenesis. We also discuss the emerging evidence on modulation of tumor microenvironment by these phytochemicals which can possibly define their cancer-specific action. Finally, we provide recent updates on how low bioavailability, a major concern with phytochemicals, is being circumvented and the general efficacy being improved, by synthesis of novel chemical analogs and nanoformulations.


Assuntos
Anti-Inflamatórios/uso terapêutico , Neoplasias/prevenção & controle , Compostos Fitoquímicos/farmacologia , Anti-Inflamatórios/farmacologia , Humanos , Medicina Tradicional , Estresse Oxidativo/efeitos dos fármacos , Compostos Fitoquímicos/uso terapêutico , Microambiente Tumoral/efeitos dos fármacos
8.
Int J Mol Sci ; 18(1)2016 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-28035959

RESUMO

Epidemiological as well as experimental evidence exists in support of chemopreventive and anticancer properties of green tea and its constituents. The gallocatechin, epicatechin-3-gallate is a major polyphenol present in green tea, shown responsible for these effects. Plant-derived polyphenolic compounds are established natural antioxidants which are capable of catalyzing oxidative DNA degradation of cellular DNA, alone as well as in the presence of transition metal ions, such as copper. Here we present evidence to support that, similar to various other polyphenoic compounds, epicatechin-3-gallate also causes oxidative degradation of cellular DNA. Single cell alkaline gel electrophoresis (Comet assay) was used to assess DNA breakage in lymphocytes that were exposed to various concentrations of epicatechin-3-gallate. Inhibition of DNA breakage in the presence of scavengers of reactive oxygen species (ROS) suggested involvement of ROS generation. Addition of neocuproine (a cell membrane permeable Cu(I) chelator) inhibited DNA degradation, dose-dependently, in intact lymphocytes. In contrast, bathocuproine, which does not permeate cell membrane, was observed to be ineffective. We further show that epicatechin-3-gallate degrades DNA in cell nuclei, which can also be inhibited by neocuproine, suggesting mobilization of nuclear copper in this reaction as well. Our results are indicative of ROS generation, possibly through mobilization of endogenous copper ions, and support our long-standing hypothesis of a prooxidant activity of plant-derived polyphenols as a mechanism for their documented anticancer properties.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Catequina/análogos & derivados , Cobre/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Catequina/farmacologia , Linhagem Celular Tumoral , Células Cultivadas , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Chá/química
9.
Toxins (Basel) ; 8(2): 37, 2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-26861392

RESUMO

Catechins, the dietary phytochemicals present in green tea and other beverages, are considered to be potent inducers of apoptosis and cytotoxicity to cancer cells. While it is believed that the antioxidant properties of catechins and related dietary agents may contribute to lowering the risk of cancer induction by impeding oxidative injury to DNA, these properties cannot account for apoptosis induction and chemotherapeutic observations. Catechin (C), epicatechin (EC), epigallocatechin (EGC) and epigallocatechin-3-gallate (EGCG) are the four major constituents of green tea. In this article, using human peripheral lymphocytes and comet assay, we show that C, EC, EGC and EGCG cause cellular DNA breakage and can alternatively switch to a prooxidant action in the presence of transition metals such as copper. The cellular DNA breakage was found to be significantly enhanced in the presence of copper ions. Catechins were found to be effective in providing protection against oxidative stress induced by tertbutylhydroperoxide, as measured by oxidative DNA breakage in lymphocytes. The prooxidant action of catechins involved production of hydroxyl radicals through redox recycling of copper ions. We also determined that catechins, particularly EGCG, inhibit proliferation of breast cancer cell line MDA-MB-231 leading to a prooxidant cell death. Since it is well established that tissue, cellular and serum copper levels are considerably elevated in various malignancies, cancer cells would be more subject to redox cycling between copper ions and catechins to generate reactive oxygen species (ROS) responsible for DNA breakage. Such a copper dependent prooxidant cytotoxic mechanism better explains the anticancer activity and preferential cytotoxicity of dietary phytochemicals against cancer cells.


Assuntos
Antineoplásicos/farmacologia , Catequina/farmacologia , Cobre/metabolismo , Radical Hidroxila/metabolismo , Superóxidos/metabolismo , Antineoplásicos/uso terapêutico , Catequina/análogos & derivados , Catequina/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaio Cometa , DNA/metabolismo , Dano ao DNA , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Neoplasias/tratamento farmacológico , Oxirredução , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
10.
Mol Nutr Food Res ; 60(6): 1251-63, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26799714

RESUMO

The landscape of cancer has changed considerably in past several years, due mainly to aggressive screening, accumulation of data from basic and epidemiological studies, and the advances in translational research. Natural anticancer agents have always been a part and parcel of cancer research. The initial focus on natural anticancer agents was in context of their cancer chemopreventive properties but their ability to selectively target oncogenic signaling pathways has also been recognized. In light of the rapid advancements in our understanding of the role of microRNAs, cancer stem cells, and epigenetic events in cancer initiation and progression, a number of natural anticancer agents are showing promise in vitro, in vivo as well as in preclinical studies. Moreover, parent structures of natural agents are being extensively modified with the hope of improving efficacy, specificity, and bioavailability. In this article, we focus on two natural agents, 3,3'-diindolylmethane and garcinol, along with 3,4-difluorobenzo curcumin, a synthetic analog of natural agent curcumin. We showcase how these anticancer agents are changing cancer landscape by modulating novel microRNAs, epigenetic factors, and cancer stem cell markers. These activities are relevant and being appreciated for overcoming drug resistance and inhibition of metastases, the two overarching clinical challenges in modern medicine.


Assuntos
Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/prevenção & controle , Antineoplásicos/farmacologia , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Curcumina/análogos & derivados , Curcumina/farmacologia , Suplementos Nutricionais , Epigênese Genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Indóis/farmacologia , MicroRNAs/genética , Células-Tronco Neoplásicas/efeitos dos fármacos , Transdução de Sinais , Terpenos/farmacologia
11.
Adv Exp Med Biol ; 890: 57-74, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26703799

RESUMO

Lung cancer is the leading cause of cancer-related deaths worldwide with a 5-year overall survival rate of less than 20 %. Considering the treatments currently available, this statistics is shocking. A possible explanation for the disconnect between sophisticated treatments and the survival rate can be related to the post-treatment enrichment of Cancer Stem Cells (CSCs), which is one of a sub-set of drug resistant tumor cells with abilities of self-renewal, cancer initiation, and further maintenance of tumors. Lung CSCs have been associated with resistance to radiation and chemotherapeutic treatments. CSCs have also been implicated in tumor recurrence because CSCs are not typically killed after conventional therapy. Investigation of CSCs in determining their role in tumor recurrence and drug-resistance relied heavily on the use of specific markers present in CSCs, including CD133, ALDH, ABCG2, and Nanog. Yet another cell type that is also associated with increased resistance to treatment is epithelial-to-mesenchymal transition (EMT) phenotypic cells. Through the processes of EMT, epithelial cells lose their epithelial phenotype and gain mesenchymal properties, rendering EMT phenotypic cells acquire drug-resistance. In this chapter, we will further discuss the role of microRNAs (miRNAs) especially because miRNA-based therapies are becoming attractive target with respect to therapeutic resistance and CSCs. Finally, the potential role of the natural agents and synthetic derivatives of natural compounds with anti-cancer activity, e.g. curcumin, CDF, and BR-DIM is highlighted in overcoming therapeutic resistance, suggesting that the above mentioned agents could be important for better treatment of lung cancer in combination therapy.


Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Curcumina/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Curcumina/análogos & derivados , Curcumina/síntese química , Resistencia a Medicamentos Antineoplásicos/genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Transdução de Sinais
12.
Crit Rev Food Sci Nutr ; 56(9): 1501-18, 2016 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-25365584

RESUMO

Neoplastic conditions associated with gastrointestinal (GI) tract are common worldwide with colorectal cancer alone accounting for the third leading rate of cancer incidence. Other GI malignancies such as esophageal carcinoma have shown an increasing trend in the last few years. The poor survival statistics of these fatal cancer diseases highlight the need for multiple alternative treatment options along with effective prophylactic strategies. Worldwide geographical variation in cancer incidence indicates a correlation between dietary habits and cancer risk. Epidemiological studies have suggested that populations with high intake of certain dietary agents in their regular meals have lower cancer rates. Thus, an impressive embodiment of evidence supports the concept that dietary factors are key modulators of cancer including those of GI origin. Preclinical studies on animal models of carcinogenesis have reflected the pharmacological significance of certain dietary agents called as nutraceuticals in the chemoprevention of GI neoplasia. These include stilbenes (from red grapes and red wine), isoflavones (from soy), carotenoids (from tomatoes), curcuminoids (from spice turmeric), catechins (from green tea), and various other small plant metabolites (from fruits, vegetables, and cereals). Pleiotropic action mechanisms have been reported for these diet-derived chemopreventive agents to retard, block, or reverse carcinogenesis. This review presents a prophylactic approach to primary prevention of GI cancers by highlighting the translational potential of plant-derived nutraceuticals from epidemiological, laboratory, and clinical studies, for the better management of these cancers through consumption of nutraceutical rich diets and their intervention in cancer therapeutics.


Assuntos
Anticarcinógenos , Dieta , Suplementos Nutricionais , Neoplasias Gastrointestinais/prevenção & controle , Animais , Carotenoides , Curcumina , Neoplasias Gastrointestinais/tratamento farmacológico , Neoplasias Gastrointestinais/epidemiologia , Humanos , Isoflavonas , Estilbenos
13.
Tumour Biol ; 36(11): 8861-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26069106

RESUMO

We have earlier elucidated a pathway for the anticancer action of plant polyphenolic compounds against malignant cells involving mobilisation of endogenous copper ions and the consequent prooxidant action. To further confirm our hypothesis in vivo, we induced hepatocellular carcinoma (HCC) in rats by diethylnitrosamine (DEN). We show that in such carcinoma cells, there is a progressive elevation in copper levels at various intervals after DEN administration. Concurrently with increasing copper levels, epigallocatechin-3-gallate (EGCG; a potent anticancer plant polyphenol found in green tea) mediated DNA breakage in malignant cells is also increased. The cell membrane permeable copper chelator neocuproine inhibited the EGCG-mediated cellular DNA degradation, whereas the membrane impermeable chelator bathocuproine was ineffective. Iron and zinc specific chelators desferoxamine mesylate and histidine, respectively, were also ineffective in inhibiting EGCG mediated DNA breakage. Through the use of specific scavengers, the mechanism of DNA breakage was determined to be mediated by reactive oxygen species. In summary, we provide an in vivo evidence of accumulating copper in hepatocellular carcinoma that is targeted by EGCG, leading to its anticancer role in a prooxidant manner. Our findings confirm a novel mechanism of anticancer activity of EGCG in particular and plant derived nutraceuticals in general.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Catequina/análogos & derivados , Cobre/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Animais , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/patologia , Catequina/administração & dosagem , Catequina/química , Permeabilidade da Membrana Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Dietilnitrosamina/toxicidade , Sequestradores de Radicais Livres/metabolismo , Humanos , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/administração & dosagem , Chá/química
14.
Nutrients ; 7(1): 321-34, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25569626

RESUMO

The relevance of naturopathy (defined as the practice of medicine for the treatment of human diseases with natural agents) in human cancer is beginning to be appreciated, as documented by renewed interest in nutraceutical research, the natural anticancer agents of dietary origin. Because of their pleiotropic effects and the ability to modulate multiple signaling pathways, which is a good attribute of natural agents, nutraceuticals have frequently been demonstrated to re-sensitize drug-resistant cancers. The effectiveness of nutraceuticals can be further enhanced if the tools for the relative assessment of their molecular targets are readily available. Such information can be critical for determining their most effective uses. Here, we discuss the anticancer potential of nutraceuticals and the associated challenges that have interfered with their translational potential as a naturopathic approach for the management of cancers. In the years to come, an efficient screening and assessment of molecular targets will be the key to make rapid progress in the area of drug design and discovery, especially focusing on evidence-based development of naturopathy for the treatment of human malignancies.


Assuntos
Suplementos Nutricionais , Naturologia/métodos , Neoplasias/terapia , Antineoplásicos/farmacologia , Desenho de Fármacos , Resistencia a Medicamentos Antineoplásicos , Humanos , Terapia de Alvo Molecular , NF-kappa B/genética , NF-kappa B/metabolismo , Transdução de Sinais
15.
Mol Nutr Food Res ; 58(3): 437-46, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24123728

RESUMO

SCOPE: Anticancer polyphenolic nutraceuticals from fruits, vegetables, and spices are generally recognized as antioxidants, but can be prooxidants in the presence of copper ions. We earlier proposed a mechanism for such activity of polyphenols and now we provide data in multiple cancer cell lines in support of our hypothesis. METHODS AND RESULTS: Through multiple assays, we show that polyphenols luteolin, apigenin, epigallocatechin-3-gallate, and resveratrol are able to inhibit cell proliferation and induce apoptosis in different cancer cell lines. Such cell death is prevented to a significant extent by cuprous chelator neocuproine and reactive oxygen species scavengers. We also show that normal breast epithelial cells, cultured in a medium supplemented with copper, become sensitized to polyphenol-induced growth inhibition. CONCLUSION: Since the concentration of copper is significantly elevated in cancer cells, our results strengthen the idea that an important anticancer mechanism of plant polyphenols is mediated through intracellular copper mobilization and reactive oxygen species generation leading to cancer cell death. Moreover, this prooxidant chemopreventive mechanism appears to be a mechanism common to several polyphenols with diverse chemical structures and explains the preferential cytotoxicity of these compounds toward cancer cells.


Assuntos
Cobre/metabolismo , Polifenóis/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Anticarcinógenos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Apigenina/farmacologia , Apoptose/efeitos dos fármacos , Catequina/análogos & derivados , Catequina/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quelantes/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Luteolina/farmacologia , Fenantrolinas/farmacologia , Resveratrol , Estilbenos/farmacologia
16.
Mol Nutr Food Res ; 58(1): 79-86, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24272883

RESUMO

Nutraceuticals, the bioactive food components represented by many naturally occurring dietary compounds, have been investigated for a few decades for their numerous beneficial effects, including their anticancer properties. The initial interest in the cancer-preventing/therapeutic ability of these agents was based on their ability to affect multiple signaling pathways that are deregulated in cancer cells. With a shift in the focus of cancer research to the emerging areas such as epigenetic regulation, microRNAs (miRNAs) and the cancer stem cells (CSCs), nutraceuticals initially appeared out of place. However, research investigations over the last several years have slowly but firmly presented evidence that supports a relevance of these agents in modern day research. While nutraceuticals are increasingly being realized to alter miRNA/CSCs expression and function, the molecular mechanism(s) are not very clearly understood. Epigenetic regulation is one mechanism by which these agents exert their anticancer effects. In this focused mini review, we summarize our current understanding of epigenetic regulation of miRNAs and CSCs by nutraceuticals. We discuss both direct and indirect evidences that support such an activity of these compounds.


Assuntos
Suplementos Nutricionais , MicroRNAs/fisiologia , Células-Tronco Neoplásicas/fisiologia , Epigênese Genética/efeitos dos fármacos , Humanos , Células-Tronco Neoplásicas/efeitos dos fármacos
17.
Cancer Metastasis Rev ; 33(2-3): 629-40, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24375392

RESUMO

Recently, nutraceuticals have received increasing attention as the agents for cancer prevention and supplement with conventional therapy. Prostate cancer (PCa) is the most frequently diagnosed cancer and second leading cause of cancer-related death in men in the US. Growing evidences from epidemiological studies, in vitro experimental studies, animal studies, and clinical trials have shown that nutraceuticals could be very useful for the prevention and treatment of PCa. Several nutraceuticals including isoflavone, indole-3-carbinol, 3,3'-diindolylmethane, lycopene, (-)-epigallocatechin-3-gallate, and curcumin are known to downregulate the signal transductions in AR, Akt, NF-κB, and other signal transduction pathways which are vital for the development of PCa and the progression of PCa from androgen-sensitive to castrate-resistant PCa. Therefore, nutraceutical treatment in combination with conventional therapeutics could achieve better treatment outcome in prostate cancer therapy. Interestingly, some nutraceuticals could regulate the function of cancer stem cell (CSC)-related miRNAs and associated molecules, leading to the inhibition of prostatic CSCs which are responsible for drug resistance, tumor progression, and recurrence of PCa. Hence, nutraceuticals may serve as powerful agents for the prevention of PCa progression and they could also be useful in combination with chemotherapeutics or radiotherapy. Such strategy could become a promising newer approach for the treatment of metastatic PCa with better treatment outcome by improving overall survival.


Assuntos
Suplementos Nutricionais , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/prevenção & controle , Pesquisa , Animais , Ensaios Clínicos como Assunto , Humanos , Masculino , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Risco , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento
18.
AAPS J ; 15(4): 991-1000, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23824838

RESUMO

Isoflavones have been investigated in detail for their role in the prevention and therapy of prostate cancer. This is primarily because of the overwhelming data connecting high dietary isoflavone intake with reduced risk of developing prostate cancer. A number of investigations have evaluated the mechanism(s) of anticancer action of isoflavones such as genistein, daidzein, biochanin A, equol, etc., in various prostate cancer models, both in vitro and in vivo. Genistein quickly jumped to the forefront of isoflavone cancer research, but the initial enthusiasm was followed by reports on its contradictory prometastatic and tumor-promoting effects. Use of soy isoflavone mixture has been advocated as an alternative, wherein daidzein can negate harmful effects of genistein. Recent research indicates a novel role of genistein and other isoflavones in the potentiation of radiation therapy, epigenetic regulation of key tumor suppressors and oncogenes, and the modulation of miRNAs, epithelial-to-mesenchymal transition, and cancer stem cells, which has renewed the interest of cancer researchers in this class of anticancer compounds. This comprehensive review article summarizes our current understanding of the role of isoflavones in prostate cancer research.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Isoflavonas/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Animais , Antineoplásicos Alquilantes/química , Antineoplásicos Alquilantes/isolamento & purificação , Ensaios Clínicos como Assunto/métodos , Genisteína/química , Genisteína/uso terapêutico , Humanos , Isoflavonas/química , Isoflavonas/isolamento & purificação , Masculino , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Neoplasias da Próstata/patologia
19.
Curr Pharm Des ; 19(11): 2047-69, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23116312

RESUMO

Curcumin is the active component of dried rhizome of Curcuma longa, a perennial herb belonging to ginger family, cultivated extensively in south and southeastern tropical Asia. It is widely consumed in the Indian subcontinent, south Asia and Japan in traditional food recipes. Extensive research over last few decades has shown that curcumin is a potent anti-inflammatory agent with powerful therapeutic potential against a variety of cancers. It suppresses proliferation and metastasis of human tumors through regulation of various transcription factors, growth factors, inflammatory cytokines, protein kinases and other enzymes. It induces apoptotic cell death and also inhibits proliferation of cancer cells by cell cycle arrest. Pharmacokinetic data has shown that curcumin undergoes rapid metabolism leading to glucuronidation and sulfation in the liver and excretion in the feces, which accounts for its poor systemic bioavailability. The compound has, therefore, been formulated and administered using different drug delivery systems such as liposomes, micelles, polysaccharides, phospholipid complexes and nanoparticles that can overcome the limitation of bioavailability to some extent. Attempts to avoid rapid metabolism of curcumin until now have been met with limited success. This has prompted researchers to look for new synthetic curcumin analogs in order to overcome the drawbacks of limited bioavailability and rapid metabolism, and gain efficacy with reduced toxicity. In this review we provide a summarized account of novel synthetic curcumin formulations and analogs, and the recent progress in the field of cancer prevention and treatment.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Curcumina/uso terapêutico , Desenho de Fármacos , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacocinética , Disponibilidade Biológica , Biotransformação , Química Farmacêutica , Curcumina/análogos & derivados , Curcumina/síntese química , Curcumina/farmacocinética , Portadores de Fármacos , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
20.
PLoS One ; 7(12): e50165, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23272057

RESUMO

Hypoxia is known to play critical roles in cell survival, angiogenesis, tumor invasion, and metastasis. Hypoxia mediated over-expression of hypoxia-inducible factor (HIF) has been shown to be associated with therapeutic resistance, and contributes to poor prognosis of cancer patients. Emerging evidence suggest that hypoxia and HIF pathways contributes to the acquisition of epithelial-to-mesenchymal transition (EMT), maintenance of cancer stem cell (CSC) functions, and also maintains the vicious cycle of inflammation-all which lead to therapeutic resistance. However, the precise molecular mechanism(s) by which hypoxia/HIF drives these events are not fully understood. Here, we show, for the first time, that hypoxia leads to increased expression of VEGF, IL-6, and CSC signature genes Nanog, Oct4 and EZH2 consistent with increased cell migration/invasion and angiogenesis, and the formation of pancreatospheres, concomitant with increased expression of miR-21 and miR-210 in human pancreatic cancer (PC) cells. The treatment of PC cells with CDF, a novel synthetic compound inhibited the production of VEGF and IL-6, and down-regulated the expression of Nanog, Oct4, EZH2 mRNAs, as well as miR-21 and miR-210 under hypoxia. CDF also led to decreased cell migration/invasion, angiogenesis, and formation of pancreatospheres under hypoxia. Moreover, CDF decreased gene expression of miR-21, miR-210, IL-6, HIF-1α, VEGF, and CSC signatures in vivo in a mouse orthotopic model of human PC. Collectively, these results suggest that the anti-tumor activity of CDF is in part mediated through deregulation of tumor hypoxic pathways, and thus CDF could become a novel, and effective anti-tumor agent for PC therapy.


Assuntos
Curcumina/análogos & derivados , Curcumina/farmacologia , Regulação da Expressão Gênica , Hipóxia , Interleucina-6/metabolismo , MicroRNAs/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Sobrevivência Celular , Citocinas/metabolismo , Humanos , Imuno-Histoquímica/métodos , Microscopia Confocal/métodos , Invasividade Neoplásica , Neovascularização Patológica , RNA Interferente Pequeno/metabolismo , Cicatrização
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