withanolides and Neoplasms

withanolides has been researched along with Neoplasms* in 38 studies

Reviews

11 review(s) available for withanolides and Neoplasms

ArticleYear
Withaferin A: A Dietary Supplement with Promising Potential as an Anti-Tumor Therapeutic for Cancer Treatment - Pharmacology and Mechanisms.
    Drug design, development and therapy, 2023, Volume: 17

    Cancer, as the leading cause of death worldwide, poses a serious threat to human health, making the development of effective tumor treatments a significant challenge. Natural products continue to serve as crucial resources for drug discovery. Among them, Withaferin A (WA), the most active phytocompound extracted from the renowned dietary supplement

    Topics: Biological Availability; Dietary Supplements; Humans; Neoplasms; Withanolides

2023
Recent Advances in the Chemistry and Therapeutic Evaluation of Naturally Occurring and Synthetic Withanolides.
    Molecules (Basel, Switzerland), 2022, Jan-28, Volume: 27, Issue:3

    Natural products are a major source of biologically active compounds that make promising lead molecules for developing efficacious drug-like molecules. Natural withanolides are found in many flora and fauna, including plants, algae, and corals, that traditionally have shown multiple health benefits and are known for their anti-cancer, anti-inflammatory, anti-bacterial, anti-leishmaniasis, and many other medicinal properties. Structures of these withanolides possess a few reactive sites that can be exploited to design and synthesize more potent and safe analogs. In this review, we discuss the literature evidence related to the medicinal implications, particularly anticancer properties of natural withanolides and their synthetic analogs, and provide perspectives on the translational potential of these promising compounds.

    Topics: Animals; Anti-Inflammatory Agents; Antineoplastic Agents; Drug Design; Drug Discovery; Humans; Neoplasms; Withanolides

2022
Potential Role of Natural Products to Combat Radiotherapy and Their Future Perspectives.
    Molecules (Basel, Switzerland), 2021, Oct-02, Volume: 26, Issue:19

    Cancer is the second leading cause of death in the world. Chemotherapy and radiotherapy (RT) are the common cancer treatments. In addition to these limitations, the development of adverse effects from chemotherapy and RT reduces the quality of life for cancer patients. Cellular radiosensitivity, or the ability to resist and overcome cell damage caused by ionizing radiation (IR), is directly related to cancer cells' response to RT. Therefore, radiobiological research is emphasizing chemical compounds 'radiosensitization of cancer cells so that they are more reactive in the IR spectrum. Recent years researchers have seen an increase in interest in natural products that have antitumor effects with minimal side effects. Natural products, on the other hand, are easy to recover and therefore less expensive. There have been several scientific studies done based on these compounds that have tested their ability in vitro and in vivo to induce tumor radiosensitization. The role of natural products in RT, as well as their usefulness and potential applications, is the goal of this current review.

    Topics: Berberine; Biological Products; Curcumin; Emodin; Genistein; Humans; Neoplasms; Pentacyclic Triterpenes; Radiation-Protective Agents; Radiation-Sensitizing Agents; Radiotherapy; Resveratrol; Sesquiterpenes; Triterpenes; Ursolic Acid; Vitamin D; Withanolides

2021
Withaferin A: From ayurvedic folk medicine to preclinical anti-cancer drug.
    Biochemical pharmacology, 2020, Volume: 173

    Despite the recent successes of targeted cancer immuno-therapies, drug resistance and disease relapse remain a huge burden in cancer patient treatment. This has fueled renewed interest in natural product discovery to identify new pharmacophores for innovative cancer drug development. Reverse pharmacology approaches of Withania somnifera leaves and roots (alternatively also called Ashwagandha or Indian ginseng in traditional Ayurvedic and Unani folk medicine) have identified Withaferin A (WA) as the most bioactive compound for treatment of inflammatory ailments, supporting traditional use of their corresponding extracts in indigenous medicine. In this review we summarize preclinical in vivo evidence for therapeutic cancer applications of WA and provide a biochemical framework of its polypharmaceutical effects against cancer hallmarks.

    Topics: Animals; Apoptosis; Humans; Medicine, Ayurvedic; Molecular Structure; Neoplasms; Phytotherapy; Withania; Withanolides; Xenograft Model Antitumor Assays

2020
    International journal of molecular sciences, 2019, Oct-25, Volume: 20, Issue:21

    Ashwagandha (

    Topics: Animals; Antineoplastic Agents, Phytogenic; Humans; Neoplasms; Withania; Withanolides

2019
Journey Describing the Cytotoxic Potential of Withanolides: A Patent Review.
    Recent patents on anti-cancer drug discovery, 2018, Volume: 13, Issue:4

    Withanolides are C-28 ergostane steroids known to demonstrate some very interesting therapeutic properties. Numerous withanolides have been isolated from a variety of different plant species and can be employed to treat various types of cancers. Withanolides are indeed capable of demonstrating excellent anticancer, anti-inflammatory, and neuroprotective activities. Additionally, libraries of prepared withaferin A analogs incorporating an acyl, sulphate, amide and aldehyde functionality have demonstrated the most potential response. It is of particular interest to note that an acetyl group at either C-4, C-19 or C-27 enhances the anticancer effects. Since the majority of natural withanolides reported in patents are classified as "Type-A", it is our opinion that there should now be a focus on developing "Type-B" withanolides and an investigation into their various therapeutic applications. Moreover, very little real innovation in synthetic methodologies has been reported which opens up huge possibilities for novel synthetic methodologies to be developed for the production of larger libraries new withanolides and their analogs to incorporate chemical diversity. In addition, since withanolides have the capability to conjugate with other anticancer compounds, this should encourage scientists to prepare lead compounds in cancer drug discovery.

    Topics: Animals; Antineoplastic Agents; Cytotoxins; Humans; Neoplasms; Patents as Topic; Withanolides

2018
Patent Survey of Resveratrol, Taxol, Podophyllotoxin, Withanolides and Their Derivatives Used in Anticancer Therapy.
    Recent patents on biotechnology, 2017, Volume: 11, Issue:2

    Resveratrol, taxol, podophyllotoxin, withanolides and their derivatives find applications in anti-cancer therapy. They are plant-derived compounds whose chemical structures and synthesis limit their natural availability and restrict a large-scale industrial production. Hence, their production by various biotechnological approaches may hold promise for a continuous and reliable mode of supply.. We review process and product patents in this regard.. Accordingly, we provide a general outline to search the freely accessible WIPO, EPO, USPTO and Cambia databases with several keywords and patent codes. We have tabulated both granted and filed patents from the said databases.. We retrieved ~40 patents from these databases. Novel biotechnological processes for production of these anticancer compounds include Agrobacterium rhizogenes-mediated hairy root culture, suspension culture, cell culture with elicitors, use of recombinant microorganisms, and bioreactors among others. The results are indicative of being both database-specific as well as queryspecific. A ten-year search window yielded 33 patents. The utility of the search strategy is discussed in the light of biotechnological developments in the field. Those who examine patent literature using similar search strategies may complement their knowledge obtained from perusal of mainstream journal resources.

    Topics: Humans; Neoplasms; Paclitaxel; Patents as Topic; Podophyllotoxin; Resveratrol; Stilbenes; Withanolides

2017
Molecular insights into cancer therapeutic effects of the dietary medicinal phytochemical withaferin A.
    The Proceedings of the Nutrition Society, 2017, Volume: 76, Issue:2

    Despite the worldwide research efforts to combat cancer, it remains a leading cause of death. Although various specific kinase inhibitors already have been approved for clinical cancer treatment, occurrence of intrinsic or acquired resistance and intermittent response over longer periods limits long-term success of single kinase-targeted therapies. In this respect, there is a renewed interest in polypharmaceutical natural compounds, which simultaneously target various hyperactivated kinases involved in tumour-inflammation, angiogenesis, cell survival, proliferation, metastasis and angiogenesis. The dietary medicinal phytochemical withaferin A (WA), isolated from Withaferin somnifera (popular Indian name Ashwagandha), holds promise as a novel anti-cancer agent, which targets multiple cell survival kinase pathways, including IκB kinase/NF-κB, PI3 kinase/protein kinase B/mammalian target of rapamycin and mitogen-activated protein kinase/extracellular signal-regulated kinase amongst others. In this review, we propose a novel mechanism of WA-dependent kinase inhibition via electrophilic covalent targeting of cysteine residues in conserved kinase activation domains (kinase cysteinome), which could underlie its pleiotropic therapeutic effects in cancer signalling.

    Topics: Animals; Cell Cycle Checkpoints; Cell Line, Tumor; Disease Models, Animal; Humans; Molecular Structure; Neoplasms; Phytochemicals; Protein Conformation; Withanolides

2017
Withania somnifera: From prevention to treatment of cancer.
    Molecular nutrition & food research, 2016, Volume: 60, Issue:6

    The identification of bioactive molecules that have potential to interrupt carcinogenesis continues to garner research interest. In particular, molecules that have dietary origin are most attractive because of their safety, cost-effectiveness and feasibility of oral administration. Nutraceuticals have played an important role in the overall well-being of humans for many years, with or without rigorous evidence backing their health claims. Traditional medicine systems around the world have utilized plants that have medicinal properties for millennia, providing an opportunity for modern day researchers to assess their efficacies against ailments such as cancer. Withania somnifera (WS) is a plant that has been used in Ayurveda (an ancient form of medicine in Asia) and in the recent past, has been demonstrated to have anti-tumorigenic properties in experimental models. While scientific research performed on WS has exploded in the past decade, much regarding the mode of action and molecular targets involved remains unknown. In this review, we discuss the traditional uses of the plant, the experimental evidence supporting its chemopreventive potential as well as roadblocks that need to be overcome in order for WS to be evaluated as a chemopreventive agent in humans.

    Topics: Animals; Asia; Cell Line, Tumor; Chemoprevention; Dietary Supplements; Disease Models, Animal; Drug Evaluation, Preclinical; Humans; Medicine, Ayurvedic; Neoplasms; Phytotherapy; Plant Extracts; Plant Roots; Withania; Withanolides

2016
Withaferin-A--A Natural Anticancer Agent with Pleitropic Mechanisms of Action.
    International journal of molecular sciences, 2016, Mar-04, Volume: 17, Issue:3

    Cancer, being the second leading cause of mortality, exists as a formidable health challenge. In spite of our enormous efforts, the emerging complexities in the molecular nature of disease progression limit the real success in finding an effective cancer cure. It is now conceivable that cancer is, in fact, a progressive illness, and the morbidity and mortality from cancer can be reduced by interfering with various oncogenic signaling pathways. A wide variety of structurally diverse classes of bioactive phytochemicals have been shown to exert anticancer effects in a large number of preclinical studies. Multiple lines of evidence suggest that withaferin-A can prevent the development of cancers of various histotypes. Accumulating data from different rodent models and cell culture experiments have revealed that withaferin-A suppresses experimentally induced carcinogenesis, largely by virtue of its potent anti-oxidative, anti-inflammatory, anti-proliferative and apoptosis-inducing properties. Moreover, withaferin-A sensitizes resistant cancer cells to existing chemotherapeutic agents. The purpose of this review is to highlight the mechanistic aspects underlying anticancer effects of withaferin-A.

    Topics: Angiogenesis Inhibitors; Animals; Anti-Inflammatory Agents; Anticarcinogenic Agents; Antineoplastic Agents, Phytogenic; Apoptosis; Cell Movement; Cell Proliferation; Humans; Neoplasm Invasiveness; Neoplasm Metastasis; Neoplasms; Withania; Withanolides

2016
Molecular targets and mechanisms of cancer prevention and treatment by withaferin a, a naturally occurring steroidal lactone.
    The AAPS journal, 2014, Volume: 16, Issue:1

    The plants used in Ayurvedic medicine, which has been practiced in India for thousands of years for the treatment of a variety of disorders, are rich in chemicals potentially useful for prevention and treatment of cancer. Withania somnifera (commonly known as Ashwagandha in Ayurvedic medicine) is one such medicinal plant whose anticancer value was realized over four decades ago after isolation of a crystalline steroidal compound (withaferin A) from the leaves of this shrub. The root and leaf extracts of W. somnifera are shown to confer protection against chemically-induced cancers in experimental rodents, and retard tumor xenograft growth in athymic mice. Anticancer effect of W. somnifera is generally attributable to steroidal lactones collectively referred to as withanolides. Withaferin A (WA) appears most active against cancer among structurally divergent withanolides isolated from the root or leaf of W. somnifera. Cancer-protective role for WA has now been established using chemically-induced and oncogene-driven rodent cancer models. This review summarizes the key in vivo preclinical studies demonstrating anticancer effects of WA. Molecular targets and mechanisms likely contributing to the anticancer effects of WA are also discussed. Finally, challenges in clinical development of WA for the prevention and treatment of cancer are highlighted.

    Topics: Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Autophagy; Cell Cycle Checkpoints; Endoplasmic Reticulum Stress; Humans; Medicine, Ayurvedic; Neoplasms; Phytotherapy; Plant Extracts; Signal Transduction; Treatment Outcome; Withania; Withanolides; Xenograft Model Antitumor Assays

2014

Other Studies

27 other study(ies) available for withanolides and Neoplasms

ArticleYear
    Journal of biomolecular structure & dynamics, 2023, Volume: 41, Issue:11

    Topics: Humans; Molecular Docking Simulation; Molecular Dynamics Simulation; Neoplasms; NF-E2-Related Factor 2; Withanolides

2023
Phytoconstituents of Withania somnifera unveiled Ashwagandhanolide as a potential drug targeting breast cancer: Investigations through computational, molecular docking and conceptual DFT studies.
    PloS one, 2022, Volume: 17, Issue:10

    Breast cancer is the second most common malignancy in females worldwide and poses a great challenge that necessitates the identification of novel therapeutic agents from several sources. This research aimed to study the molecular docking and molecular dynamics simulations of four proteins (such as PDB: 6CBZ, 1FDW, 5GWK and 2WTT) with the selected phytochemicals from Withania somnifera to identify the potential inhibitors for breast cancer. The molecular docking result showed that among 44 compounds, two of them, Ashwagandhanolide and Withanolide sulfoxide have the potential to inhibit estrogen receptor alpha (ERα), 17-beta-hydroxysteroid -dehydrogenase type 1 (17β-HSD1), topoisomerase II alpha (TOP2A) and p73 tetramerization domain that are expressed during breast cancer. The molecular dynamics (MD) simulations results suggested that Ashwagandhanolide remained inside the binding cavity of four targeted proteins and contributed favorably towards forming a stable protein-ligand complex throughout the simulation. Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) properties confirmed that Ashwagandhanolide is hydrophobic and has moderate intestinal permeability, good intestinal absorption, and poor skin permeability. The compound has a relatively low VDss value (-1.652) and can be transported across ABC transporter and good central nervous system (CNS) permeability but did not easily cross the blood-brain barrier (BBB). This compound does not possess any mutagenicity, hepatotoxicity and skin sensitization. Based on the results obtained, the present study highlights the anticancer potential of Ashwagandhanolide, a compound from W. somnifera. Furthermore, in vitro and in vivo studies are necessary to perform before clinical trials to prove the potentiality of Ashwagandhanolide.

    Topics: ATP-Binding Cassette Transporters; DNA Topoisomerases, Type II; Drug Delivery Systems; Ergosterol; Estrogen Receptor alpha; Hydroxysteroids; Ligands; Molecular Docking Simulation; Molecular Dynamics Simulation; Neoplasms; Sulfoxides; Withania; Withanolides

2022
Preparation and characterization of withaferin A loaded pegylated nanoliposomal formulation with high loading efficacy: In vitro and in vivo anti-tumour study.
    Materials science & engineering. C, Materials for biological applications, 2021, Volume: 128

    Withaferin A (WA) is a natural steroidal lactone with promising therapeutic applications. However, its clinical application is limited due to the low bioavailability and hydrophobic nature. In this study, we had prepared PEGylated nanoliposomal withaferin A (LWA) using thin-film hydration method. Dynamic light scattering, Transmission electron microscopy, and HPLC were used to investigate the impact of prepared formulations on the size, charge, morphology, and encapsulation efficiency of the LWA. The prepared nanoliposomal system had spherical vesicles, with the mean particle size of 125 nm and had an encapsulation efficiency of 83.65% with good stability. The characterization results indicated that nanoliposomal formulation is able to improve biocompatibility and bioavailability of WA. In vitro drug release study showed that LWA had an enhanced sustained drug release effect than the free drug. In vitro studies using ascites cell lines (DLA and EAC) showed that LWA treatment could induce apoptosis in ascites cells evidenced by acridine orange/ethidium bromide, Hoechst, and Giemsa staining. In vivo tumour study revealed that LWA treatment significantly reduced tumour growth and improved survival in DLA tumour bearing mice. In vivo results further demonstrated that LWA mitigated solid tumour development by regulating Ki-67 and cyclin D1 protein expression. The overall study results reveal that nanoliposome encapsulated WA exhibits therapeutic efficacy over WA in regulating tumour development as evidenced from ascites cell apoptosis as well as experimental tumour reduction studies.

    Topics: Animals; Liposomes; Mice; Neoplasms; Polyethylene Glycols; Withanolides

2021
[Withania somnifera: a kind of food-medicine plant popular in world in recent years].
    Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica, 2021, Volume: 46, Issue:20

    Withania somnifera, also known as Indian ginseng, is an important traditional medicine in the Ayurvedic medical system of India, which has a significant effect of adaptation. Modern studies have shown that the main chemical components of W. somnifera are withanolides, which have antioxidant, anti-tumor, enhancing immunity, cardiovascular protection, neuroprotection, anti-stress, anti-stress reaction and hypoglycemic activities. Studies on human, animal, mutagenesis, genotoxicity, reproductive toxicity and drug interaction showed that W. somnifera had good safety. Clinical trials have proved that W. somnifera is effective in treating a variety of human diseases. As a famous traditional medicine and modern dietary supplement, it has a high reputation and market in the international health product market, but in China, there is little scientific research, market development, product introduction and application. In this paper, the traditional application, chemical composition, pharmacological activity, safety evaluation and clinical study of the plant were introduced, so as to increase the understanding of the dual use of the plant, and to provide reference for the future introduction of the product, the service to the health of the Chinese people and the promotion of the "double cycle" of the trade of health products between China and the international community.

    Topics: Animals; China; Humans; Neoplasms; Plant Extracts; Withania; Withanolides

2021
Preparation, Characterization, and Pharmacological Investigation of Withaferin-A Loaded Nanosponges for Cancer Therapy; In Vitro, In Vivo and Molecular Docking Studies.
    Molecules (Basel, Switzerland), 2021, Nov-19, Volume: 26, Issue:22

    Topics: Animals; Apoptosis; Calorimetry, Differential Scanning; Female; Humans; MCF-7 Cells; Mice; Mice, Inbred BALB C; Molecular Docking Simulation; Neoplasms; Withania; Withanolides; Xenograft Model Antitumor Assays

2021
Isolation and characterization of cytotoxic withanolides from the calyx of Physalis alkekengi L. var franchetii.
    Bioorganic chemistry, 2020, Volume: 96

    Phytochemical investigation into the calyx of Physalis alkekengi L. var franchetii (Mast) Makino resulted in the isolation of ten cytotoxic withanolides, including five new withanolides, 1-5. Compounds 2-4 were obtained as epimeric withaphysalins. The new structures were elucidated by extensive spectroscopic analyses and electronic circular dichroism (ECD) calculations. The withanolides were evaluated for their cytotoxic activities against the A549 and K562 cell lines. Compounds 1 and 8 exhibited potent cytotoxic activity against both cell lines with IC

    Topics: A549 Cells; Antineoplastic Agents, Phytogenic; Apoptosis; Cell Line, Tumor; Humans; Neoplasms; Physalis; Plant Extracts; Withanolides

2020
Withanolide A extends the lifespan in human EGFR-driven cancerous Caenorhabditis elegans.
    Experimental gerontology, 2018, Volume: 104

    The conserved EGFR pathway is linked with multiple cancers in humans including breast, ovarian, and lung carcinoma. Withanolide A, one of the major withanolidal active compounds isolated from the Withania somnifera, extends lifespan and ameliorates stress resistance in wild-type C. elegans by targeting the Insulin/IGF-1 signaling pathway. Up-regulation of IGF1 can transactivate EGFR which inturn reduces longevity and promotes tumor development in an organism. We examined the effects of Withanolide A on the lifespan of a human EGFR-driven C. elegans transgenic model exhibiting the multivulva (Muv) phenotype. The results showed that WA extends the lifespan of both wild human EGFR-driven C. elegans model (human wild-type tyrosine kinase) as well as models bearing single (L858R), and double mutations (T790M-L858R). The lifespan extension observed in these transgenic strains was 20.35, 24.21 and 21.27%, respectively. Moreover, the reduced fat levels were noticed in both wild-type N2 worms and transgenic strains. These observations support the heathspan promoting effect of WA as lipid-rich diet has been reported to promote tumor development. In view of the fact that most of the well known FDA approved drugs such as gefitinib fail to inhibit the EGFR-associated cancers because of these mutations, the present findings show the potential of Withanolide A as a foreseen future nutraceutical to improve the average survival of cancer patients.

    Topics: Adipose Tissue; Animals; Caenorhabditis elegans; ErbB Receptors; Longevity; Neoplasms; Oxidative Stress; Phytotherapy; Plant Extracts; Up-Regulation; Withania; Withanolides

2018
Cytotoxic withanolides from the aerial parts of Tubocapsicum anomalum.
    Bioorganic chemistry, 2018, Volume: 81

    Ten new withanolides (1-10) and three artificial withanolides (11-13) were isolated from the aerial parts of Tubocapsicum anomalum, together with five known analogues (14-18). Their structures were determined on the basis of extensive spectroscopic and chemical methods. They include seven acnistin-type (1-4, 11, 14 and 15), three withajardin-type (5-7), and eight normal-type (8-10, 12, 13 and 16-18) withanolides. Of normal-type withanolides, a chemical conversion from the 16α,17α-epoxywithanolide (16) to Δ

    Topics: Antineoplastic Agents, Phytogenic; Cell Line, Tumor; Cell Survival; Cytotoxins; Humans; Models, Molecular; Neoplasms; Plant Components, Aerial; Solanaceae; Withanolides

2018
Withaferin-A kills cancer cells with and without telomerase: chemical, computational and experimental evidences.
    Cell death & disease, 2017, 04-20, Volume: 8, Issue:4

    Maintenance of telomere length is the most consistent attribute of cancer cells. Tightly connected to their capacity to overcome replicative mortality, it is achieved either by activation of telomerase or an Alternative mechanism of Lengthening of Telomeres (ALT). Disruption of either of these mechanisms has been shown to induce DNA damage signalling leading to senescence or apoptosis. Telomerase inhibitors are considered as potential anticancer drugs but are ineffective for ALT cancers (~15% of all cancers). Withaferin-A (Wi-A), a major constituent of the medicinal plant, Withania somnifera (Ashwagandha), has been shown to exert anti-tumour activity. However, its effect on either telomerase or ALT mechanisms has not been investigated. Here, by using isogenic cancer cells with/without telomerase, we found that Wi-A caused stronger cytotoxicity to ALT cells. It was associated with inhibition of ALT-associated promyelocytic leukemia nuclear bodies, an established marker of ALT. Comparative analyses of telomerase positive and ALT cells revealed that Wi-A caused stronger telomere dysfunction and upregulation of DNA damage response in ALT cells. Molecular computational and experimental analyses revealed that Wi-A led to Myc-Mad mediated transcriptional suppression of NBS-1, an MRN complex protein that is an essential component of the ALT mechanism. The results suggest that Wi-A could be a new candidate drug for ALT cancers.

    Topics: Binding Sites; Cell Cycle Checkpoints; Cell Death; Cell Line, Tumor; DNA; Down-Regulation; Humans; Models, Molecular; Molecular Dynamics Simulation; Multiprotein Complexes; Neoplasms; Phenotype; Protein Binding; Telomerase; Telomere; Telomere Homeostasis; Withanolides

2017
Bioactive new withanolides from the cultured soft coral Sinularia brassica.
    Bioorganic & medicinal chemistry letters, 2017, 08-01, Volume: 27, Issue:15

    Continuing study of the ethyl acetate (EtOAc) extract of the cultured soft coral Sinularia brassica afforded five new withanolides, sinubrasolides H-L (1-5). The structures of the new compounds were elucidated on the basis of spectroscopic analysis. The cytotoxicities of new compounds 1-5 and a known compound sinubrasolide A (6) against the proliferation of a limited panel of cancer cell lines were assayed. The anti-inflammatory activities of compounds 1-6 were evaluated by measuring their ability to suppress N-formyl-methionyl-leucyl-phenyl-alanine/cytochalasin B (fMLP/CB)-induced superoxide anion generation and elastase release in human neutrophils.

    Topics: Animals; Anthozoa; Anti-Inflammatory Agents; Antineoplastic Agents; Cell Line, Tumor; Cytochalasin B; Humans; Models, Molecular; Neoplasms; Neutrophils; Pancreatic Elastase; Superoxides; Withanolides

2017
Lipopolysaccharides-stimulated macrophage products enhance Withaferin A-induced apoptosis via activation of caspases and inhibition of NF-κB pathway in human cancer cells.
    Molecular immunology, 2017, Volume: 81

    Macrophages, as a major cellular component in tumor microenvironment, play an important role in tumor progression. However, their roles in modulation of cytotoxic chemotherapy are still not fully understood. Here, we investigated the influence of Lipoplysaccharides (LPS)-stimulated macrophage products (LSMP) on Withaferin A (WA), a natural compound that derived from the medicinal plant Withania somnifera, as an antitumor agent in human breast cancer cells MDA-MB-231 and prostate cancer cells PC-3. Our results revealed that LSMP may enhance WA-induced apoptosis in both cell lines, the underlying mechanisms of which are closely associated with activation of caspase-8, -9 and -3, cleavage of poly ADP-ribose polymerase (PARP), as well as specifically inhibiting the translocation of nuclear factor-κB (NF-κB) and down-regulation of anti-apoptotic proteins X-linked inhibitor of apoptosis protein (XIAP) and inhibitor of apoptosis protein (cIAP1/2). These findings demonstrate that macrophages in tumor microenvironment can modulate tumor responses to chemotoxic agents, providing an effective strategy that targets macrophages to enhance the antitumor efficacy of cytotoxic chemotherapy.

    Topics: Animals; Antineoplastic Agents; Apoptosis; Blotting, Western; Caspases; Cell Line, Tumor; Cell Proliferation; Culture Media, Conditioned; Enzyme Activation; Female; Flow Cytometry; Gene Knockdown Techniques; Humans; Lipopolysaccharides; Macrophages; Mice; Mice, Inbred BALB C; Neoplasms; NF-kappa B; Polymerase Chain Reaction; Signal Transduction; Tumor Microenvironment; Withanolides

2017
Importance of ROS-mediated autophagy in determining apoptotic cell death induced by physapubescin B.
    Redox biology, 2017, Volume: 12

    Physapubescin B, a steroidal compound extracted from the plant Physalis pubescens L. (Solanaceae), has been reported to possess anti-cancer potential, whereas the molecular mechanism remains elusive. In this study, we first demonstrated that physapubescin B induced autophagy in human cancer cells based on the evidence that physapubescin B increased lipidation of microtubule-associated protein 1 light chain 3 (LC3) as well as number of GFP-LC3 puncta. We further examined the molecular mechanisms and found that physapubescin B enhanced the autophagic flux through promotion of reactive oxygen species (ROS)-mediated suppression of mammalian target of rapamycin complex I (mTORC1), the key negative regulator of autophagy. Additionally, excessive ROS caused by physapubescin B also induced p53-dependent apoptotic cell death. Furthermore, we provided evidence that inhibition of autophagy either by a chemical inhibitor or gene silencing promoted physapubescin B-induced apoptotic cell death, indicating that autophagy serves as a cell survival mechanism to protect cell death. Thus, our data provide a clue that inhibition of autophagy would serve as a novel strategy for enhancing the anti-cancer potential of physapubescin B.

    Topics: Antineoplastic Agents, Phytogenic; Autophagy; Cell Survival; HCT116 Cells; HeLa Cells; Humans; Mechanistic Target of Rapamycin Complex 1; Microtubule-Associated Proteins; Neoplasms; Reactive Oxygen Species; Tumor Suppressor Protein p53; Withanolides

2017
Par-4 dependent modulation of cellular β-catenin by medicinal plant natural product derivative 3-azido Withaferin A.
    Molecular carcinogenesis, 2016, Volume: 55, Issue:5

    Here, we provide evidences that natural product derivative 3-azido Withaferin A (3-AWA) abrogated EMT and invasion by modulating β-catenin localization and its transcriptional activity in the prostate as well as in breast cancer cells. This study, for the first time, reveals 3-AWA treatment consistently sequestered nuclear β-catenin and augmented its cytoplasmic pool as evidenced by reducing β-catenin transcriptional activity in these cells. Moreover, 3-AWA treatment triggered robust induction of pro-apoptotic intracellular Par-4, attenuated Akt activity and rescued Phospho-GSK3β (by Akt) to promote β-catenin destabilization. Further, our in vitro studies demonstrate that 3-AWA treatment amplified E-cadherin expression along with sharp downregulation of c-Myc and cyclin D1 proteins. Strikingly, endogenous Par-4 knock down by siRNA underscored 3-AWA mediated inhibition of nuclear β-catenin was Par-4 dependent and suppression of Par-4 activity, either by Bcl-2 or by Ras transfection, restored the nuclear β-catenin level suggesting Par-4 mediated β-catenin regulation was not promiscuous. In vivo results further demonstrated that 3-AWA was effective inhibitor of tumor growth and immunohistochemical studies indicated that increased expression of total β-catenin and decreased expression of phospho-β-catenin and Par-4 in breast cancer tissues as compared to normal breast tissue suggesting Par-4 and β-catenin proteins are mutually regulated and inversely co-related in normal as well as cancer condition. Thus, strategic regulation of intracellular Par-4 by 3-AWA in diverse cancers could be an effective tool to control cancer cell metastasis. Conclusively, this report puts forward a novel approach of controlling deregulated β-catenin signaling by 3-AWA induced Par-4 protein.

    Topics: Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Apoptosis Regulatory Proteins; beta Catenin; Cell Line, Tumor; Epithelial-Mesenchymal Transition; Female; Gene Expression Regulation, Neoplastic; Humans; MCF-7 Cells; Mice; Neoplasms; Phosphorylation; Plants, Medicinal; Signal Transduction; Withanolides

2016
Molecular docking and dynamic simulation studies evidenced plausible immunotherapeutic anticancer property by Withaferin A targeting indoleamine 2,3-dioxygenase.
    Journal of biomolecular structure & dynamics, 2015, Volume: 33, Issue:12

    Indoleamine 2,3-dioxygenase (IDO) is emerging as an important new therapeutic drug target for the treatment of cancer characterized by pathological immune suppression. IDO catalyzes the rate-limiting step of tryptophan degradation along the kynurenine pathway. Reduction in local tryptophan concentration and the production of immunomodulatory tryptophan metabolites contribute to the immunosuppressive effects of IDO. Presence of IDO on dentritic cells in tumor-draining lymph nodes leading to the activation of T cells toward forming immunosuppressive microenvironment for the survival of tumor cells has confirmed the importance of IDO as a promising novel anticancer immunotherapy drug target. On the other hand, Withaferin A (WA) - active constituent of Withania Somnifera ayurvedic herb has shown to be having a wide range of targeted anticancer properties. In the present study conducted here is an attempt to explore the potential of WA in attenuating IDO for immunotherapeutic tumor arresting activity and to elucidate the underlying mode of action in a computational approach. Our docking and molecular dynamic simulation results predict high binding affinity of the ligand to the receptor with up to -11.51 kcal/mol of energy and 3.63 nM of IC50 value. Further, de novo molecular dynamic simulations predicted stable ligand interactions with critically important residues SER167; ARG231; LYS377, and heme moiety involved in IDO's activity. Conclusively, our results strongly suggest WA as a valuable small ligand molecule with strong binding affinity toward IDO.

    Topics: Antineoplastic Agents; Binding Sites; Binding, Competitive; Humans; Indoleamine-Pyrrole 2,3,-Dioxygenase; Kinetics; Ligands; Molecular Docking Simulation; Molecular Dynamics Simulation; Molecular Structure; Neoplasms; Protein Binding; Protein Structure, Tertiary; Tryptophan; Water; Withania; Withanolides

2015
Cytotoxic taccalonolides and withanolides from Tacca chantrieri.
    Planta medica, 2015, Volume: 81, Issue:3

    Six new taccalonolides, taccalonolides AT-AY (1-6), and two new withanolides, chantriolides D and E (7 and 8), together with ten known compounds (9-18), have been isolated from whole plants of Tacca chantrieri. The structures, including the absolute configurations of some of the compounds, were determined by spectroscopic and chemical methods. All compounds were evaluated for their in vitro cytotoxicity against five tumor cell lines. Compounds 9, 10, 13-15, and 17 exhibited cytotoxic activity, with IC50 values of 1.13-5.71 µM, while compound 7 showed selective cytotoxicity. The results indicated that taccalonolides with a six-membered lactone moiety located at C-15 and C-24 were devoid of cytotoxicity against five tumor cell lines (> 10 µM).

    Topics: Antineoplastic Agents, Phytogenic; Dioscoreaceae; HCT116 Cells; Hep G2 Cells; Humans; Molecular Structure; Neoplasms; Phytotherapy; Steroids; Withanolides

2015
Withaferin A Analogs That Target the AAA+ Chaperone p97.
    ACS chemical biology, 2015, Aug-21, Volume: 10, Issue:8

    Understanding the mode of action (MOA) of many natural products can be puzzling with mechanistic clues that seem to lack a common thread. One such puzzle lies in the evaluation of the antitumor properties of the natural product withaferin A (WFA). A variety of seemingly unrelated pathways have been identified to explain its activity, suggesting a lack of selectivity. We now show that WFA acts as an inhibitor of the chaperone, p97, both in vitro and in cell models in addition to inhibiting the proteasome in vitro. Through medicinal chemistry, we have refined the activity of WFA toward p97 and away from the proteasome. Subsequent studies indicated that these WFA analogs retained p97 activity and cytostatic activity in cell models, suggesting that the modes of action reported for WFA could be connected by proteostasis modulation. Through this endeavor, we highlight how the parallel integration of medicinal chemistry with chemical biology offers a potent solution to one of natures' intriguing molecular puzzles.

    Topics: Adenosine Triphosphatases; Antineoplastic Agents, Phytogenic; Cell Line, Tumor; HEK293 Cells; Humans; Models, Molecular; Neoplasms; Nuclear Proteins; Proteasome Endopeptidase Complex; Withanolides

2015
Hedgehog inhibitors from Withania somnifera.
    Bioorganic & medicinal chemistry letters, 2015, Sep-01, Volume: 25, Issue:17

    The hedgehog (Hh) signaling pathway performs an important role in embryonic development and in cellular proliferation and differentiation. However, aberrant activation of the Hh signaling pathway is associated with tumorigenesis. Hh signal inhibition was evaluated using a cell-based assay system that targets GLI1-mediated transcription. Activity-guided isolation of the Withania somnifera MeOH extract led to the isolation of six compounds: withaferin A (1) and its derivatives (2-6). Compounds 1 and 2 showed strong inhibition of Hh/GLI1-mediated transcriptional activity with IC50 values of 0.5 and 0.6 μM, respectively. Compounds 1, 2, 3, and 6 were cytotoxic toward human pancreatic (PANC-1), prostate (DU145) and breast (MCF7) cancer cells. Furthermore, 1 also inhibited GLI1-DNA complex formation in EMSA.

    Topics: Antineoplastic Agents, Phytogenic; Cell Line, Tumor; Female; Hedgehog Proteins; Humans; Male; Neoplasms; Signal Transduction; Withania; Withanolides

2015
Withanolides from Withania somnifera Dunal: development of cellular technology and their production.
    Recent patents on biotechnology, 2014, Volume: 8, Issue:1

    Withania somnifera Dunal is one of the most commonly used plants in Ayurvedic and indigenous system of medicine in India for over thousands of years. In view of its varied therapeutic potential, the plant has also been the subject of considerable scientific attention. The major chemical constituents of the Withania genus, the withanolides, are a group of naturally occurring C28-steroidal lactones built on an intact or rearranged ergostane framework, in which C22 and C26 are oxidized to form a six-member lactone ring. In recent years, numerous pharmacological investigations have been carried out utilizing W. somnifera extracts and several patents have been filed on pharmacological and medicinal importance of withanolides and extracts of W. somnifera, individually or in combination. Considering the immense importance of withanolides for medicinal purposes, the establishment of strategies to improve withanolides yield are highly desirable. Under natural conditions, W. somnifera possesses restricted levels of withanolides then, alternatives for obtaining withanolides in better yields are imperative. In vitro approaches followed by metabolic engineering could be attractive tools to achieve this goal. Therefore, we present here an overview of the development of various protocols for in vitro tissue regeneration from W. somnifera and in vitro secondary metabolite production as well. The review also gives an account of selected patents on various important activities of phytochemicals and extracts of W. somnifera.

    Topics: Antineoplastic Agents; Cell Culture Techniques; Humans; Inflammation; Neoplasms; Patents as Topic; Plant Cells; Plant Roots; Plant Shoots; Withania; Withanolides

2014
Withanone-rich combination of Ashwagandha withanolides restricts metastasis and angiogenesis through hnRNP-K.
    Molecular cancer therapeutics, 2014, Volume: 13, Issue:12

    Ashwagandha is an important herb used in the Indian system of traditional home medicine, Ayurveda. Alcoholic extract (i-Extract) from its leaves and its component, withanone, were previously shown to possess anticancer activity. In the present study, we developed a combination of withanone and withaferin A, major withanolides in the i-Extract, that retained the selective cancer cell killing activity and found that it also has significant antimigratory, -invasive, and -angiogenic activities, in both in vitro and in vivo assays. Using bioinformatics and biochemical approaches, we demonstrate that these phytochemicals caused downregulation of migration-promoting proteins hnRNP-K, VEGF, and metalloproteases and hence are candidate natural drugs for metastatic cancer therapy.

    Topics: Animals; Antineoplastic Agents, Phytogenic; Cell Line, Tumor; Cell Movement; Cell Proliferation; Disease Models, Animal; Heterogeneous-Nuclear Ribonucleoprotein K; Human Umbilical Vein Endothelial Cells; Humans; Mice; Models, Molecular; Molecular Conformation; Neoplasm Metastasis; Neoplasms; Neovascularization, Pathologic; Plant Extracts; Reproducibility of Results; Triterpenes; Tumor Burden; Withanolides; Xenograft Model Antitumor Assays

2014
JNK-NQO1 axis drives TAp73-mediated tumor suppression upon oxidative and proteasomal stress.
    Cell death & disease, 2014, Oct-23, Volume: 5

    Hyperproliferating cancer cells produce energy mainly from aerobic glycolysis, which results in elevated ROS levels. Thus aggressive tumors often possess enhanced anti-oxidant capacity that impedes many current anti-cancer therapies. Additionally, in ROS-compromised cancer cells ubiquitin proteasome system (UPS) is often deregulated for timely removal of oxidized proteins, thus enabling cell survival. Taken that UPS maintains the turnover of factors controlling cell cycle and apoptosis--such as p53 or p73, it represents a promising target for pharmaceutical intervention. Enhancing oxidative insult in already ROS-compromised cancer cells appears as an attractive anti-tumor scenario. TAp73 is a bona fide tumor suppressor that drives the chemosensitivity of some cancers to cisplatin or γ-radiation. It is an important drug target in tumors where p53 is lost or mutated. Here we discovered a novel synergistic mechanism leading to potent p73 activation and cancer cell death by oxidative stress and inhibition of 20S proteasomes. Using a small-molecule inhibitor of 20S proteasome and ROS-inducer--withaferin A (WA), we found that WA-induced ROS activates JNK kinase and stabilizes phase II anti-oxidant response effector NF-E2-related transcription factor (NRF2). This results in activation of Nrf2 target--NQO1 (NADPH quinone oxidoreductase), and TAp73 protein stabilization. The observed effect was ablated by the ROS scavenger--NAC. Concurrently, stress-activated JNK phosphorylates TAp73 at multiple serine and threonine residues, which is crucial to ablate TAp73/MDM2 complex and to promote TAp73 transcriptional function and induction of robust apoptosis. Taken together our data demonstrate that ROS insult in combination with the inhibition of 20S proteasome and TAp73 activation endows synthetic lethality in cancer cells. Thus, our results may enable the establishment of a novel pharmacological strategy to exploit the enhanced sensitivity of tumors to elevated ROS and proteasomal stress to kill advanced tumors by pharmacological activation of TAp73 using molecules like WA.

    Topics: Animals; Antioxidants; Apoptosis; Cell Line, Tumor; Cell Proliferation; DNA-Binding Proteins; Gene Deletion; Humans; JNK Mitogen-Activated Protein Kinases; Mice; Models, Biological; NAD(P)H Dehydrogenase (Quinone); Neoplasms; NF-E2-Related Factor 2; Nuclear Proteins; Oxidative Stress; Phosphorylation; Proteasome Endopeptidase Complex; Protein Stability; Reactive Oxygen Species; Signal Transduction; Stress, Physiological; Transcription, Genetic; Tumor Protein p73; Tumor Suppressor Protein p53; Tumor Suppressor Proteins; Withanolides

2014
Withanone as an inhibitor of survivin: a potential drug candidate for cancer therapy.
    Journal of biotechnology, 2013, Oct-20, Volume: 168, Issue:2

    Survivin, the smallest inhibitor of apoptosis protein, which has been reported to be highly expressed in almost all known cancers, plays a dual role in survival as well as the proliferation of cancer cells. It inhibits apoptosis by inhibiting caspases as well as facilitating mitosis by becoming a part of chromosomal passenger complex through its BIR5 domain. Docking studies carried out with herbal ligand withanone derived from roots of Withania somnifera have shown strong binding affinity of -19.1088 kJ/mol with BIR5 domain of survivin and in turn interferes with inhibitory action against caspases and may lead to apoptosis. Binding of withanone at BIR5 domain of survivin may also interfere with chromosomal passenger complex and lead to halt the mitotic process within the cancer cell. Docking studies support various experimental outcomes and suggest withanone as a potential candidate molecule in cancer therapy.

    Topics: Antineoplastic Agents; Apoptosis; Caspases; Humans; Hydrophobic and Hydrophilic Interactions; Inhibitor of Apoptosis Proteins; Mitosis; Models, Molecular; Molecular Docking Simulation; Molecular Targeted Therapy; Neoplasms; Protein Conformation; Protein Interaction Domains and Motifs; Survivin; Triterpenes; Withanolides

2013
Withanone binds to mortalin and abrogates mortalin-p53 complex: computational and experimental evidence.
    The international journal of biochemistry & cell biology, 2012, Volume: 44, Issue:3

    Mortalin binds to p53 tumor suppressor protein and sequesters it in the cytoplasm. This results in an inhibition of the transcriptional activation and control of centrosome duplication functions of p53, thus contributing to human carcinogenesis. Abrogation of mortalin-p53 interaction and reactivation of p53 function could be a valid proposition for cancer therapy. In the present study, we first investigated in silico the interaction of withanone, a withanolide with anticancer activity, with mortalin. We found that withanone could bind to mortalin in a region, earlier predicted critical for binding to p53. Cationic rhodacyanine dye, MKT-077 has also shown to bind the same region and kill cancer cells selectively. We report the molecular dynamic simulations revealing the thermodynamic and structural stability of the withanone-mortalin complexes. We also demonstrate the experimental evidence of abrogation of mortalin-p53 complex by withanone resulting in nuclear translocation and functional reactivation of p53 in human cancer cells. The present study establishes a molecular interaction basis that could be used for screening and development of anticancer drugs with low toxicity to normal cells. Accurate knowledge of the 3D structure of mortalin would further enhance the potential of such analyses to understand the molecular basis of mortalin biology and mortalin based cancer therapy.

    Topics: Active Transport, Cell Nucleus; Cell Nucleus; Computational Biology; Drug Screening Assays, Antitumor; HSP70 Heat-Shock Proteins; Humans; Neoplasms; Protein Binding; Triterpenes; Tumor Suppressor Protein p53; Withania; Withanolides

2012
LXR-α selectively reprogrammes cancer cells to enter into apoptosis.
    Molecular and cellular biochemistry, 2011, Volume: 349, Issue:1-2

    There exists a general recognition of the fact that LXR-α, being a member of the nuclear receptor family, plays a crucial role in the biological process that connects inflammation, cholesterol homeostasis, and cellular decisions. In this context the present study was addressed to understand the role of LXR-α gene in the selective and specific reprogramming of cancer cells into a state of apoptosis leaving the normal cells unaffected. The results of this study revealed that LXR-α gene when activated in cancerous cells of diverse origin results in the regulation of genes coding for Bcl-2, AATF, and Par-4 in a fashion, forcing these cells to enter into the state of apoptosis leaving the normal cells unaffected. On the basis of this study we propose that in near future LXR-α agonist (Withaferin A) may definitely find its use in the therapeutic interventions directed towards the treatment of cancer.

    Topics: Antineoplastic Agents; Apoptosis; Basic Helix-Loop-Helix Transcription Factors; Cell Cycle; Cell Line, Tumor; Cell Survival; E2F1 Transcription Factor; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Genes, Reporter; Humans; Hydroxycholesterols; Ligands; Liver X Receptors; Neoplasms; Orphan Nuclear Receptors; Protein Binding; Response Elements; RNA Interference; Signal Transduction; Sterol Regulatory Element Binding Protein 1; T-Lymphocytes; Transcription, Genetic; Tumor Suppressor Proteins; Withanolides

2011
Blocking the chaperone kinome pathway: mechanistic insights into a novel dual inhibition approach for supra-additive suppression of malignant tumors.
    Biochemical and biophysical research communications, 2011, Jan-07, Volume: 404, Issue:1

    The chaperone Hsp90 is involved in regulating the stability and activation state of more than 200 'client' proteins and takes part in the cancer diseased states. The major clientele-protein kinases depend on Hsp90 for their proper folding and functioning. Cdc37, a kinase targeting co-chaperone of Hsp90, mediates the interactions between Hsp90 and protein kinases. Targeting of Cdc37 has the prospect of delivering predominantly kinase-selective molecular responses as compared to the current pharmacologic Hsp90 inhibitors. The present work reports a bio-computational study carried out with the aim of exploring the dual inhibition of Hsp90/Cdc37 chaperone/co-chaperone association complex by the naturally occurring drug candidates withaferin A and 17-DMAG along with their possible modes of action. Our molecular docking studies reveal that withaferin A in combination with 17-DMAG can act as potent chaperone system inhibitors. The structural and thermodynamic stability of the ligands' bound complex was also observed from molecular dynamics simulations in water. Our results suggest a novel tumor suppressive action mechanism of herbal ligands which can be looked forward for further clinical investigations for possible anticancer drug formulations.

    Topics: Antineoplastic Agents; Benzoquinones; Cell Cycle Proteins; Chaperonins; HSP90 Heat-Shock Proteins; Humans; Lactams, Macrocyclic; Ligands; Molecular Chaperones; Molecular Dynamics Simulation; Neoplasms; Protein Structure, Tertiary; Thermodynamics; Withanolides

2011
Hsp90/Cdc37 chaperone/co-chaperone complex, a novel junction anticancer target elucidated by the mode of action of herbal drug Withaferin A.
    BMC bioinformatics, 2011, Feb-15, Volume: 12 Suppl 1

    HSPs (Heat shock proteins) are highly conserved ubiquitous proteins among species which are involved in maintaining appropriate folding and conformation of other proteins and are thus referred to as molecular chaperones. Hsp90 (Heat-shock protein 90 kDa) is one of a group of molecular chaperones responsible for managing protein folding and quality control in cell environment. However it is also involved in the maturation and stabilization of a wide range of oncogenic client proteins which are crucial for oncogenesis and malignant progression. Hsp90 requires a series of co-chaperones to assemble into a super-chaperone complex for its function. These co-chaperones bind and leave the complex at various stages to regulate the chaperoning process. Arresting the chaperone cycle at these stages by targeting different co-chaperone/Hsp90 interactions seems to be quite a viable alternative and is likely to achieve similar consequences as that of Hsp90 direct inhibition with added favors of high specificity and reduced side effect profile. The study conducted here is an attempt to explore the potential of Withania somnifera's major constituent WA (Withaferin A) in attenuating the Hsp90/Cdc37 chaperone/co-chaperone interactions for enhanced tumor arresting activity and to elucidate the underlying mode of action using computational approaches.. Formation of active Hsp90/Cdc37 complex is one of the essential steps for facilitation of chaperone client interaction, non-assembly of which can lead to prevention of the chaperone-client association resulting in apoptosis of tumor cells. From our flexible docking analysis of WA into active Hsp90/Cdc37 complex in which key interfacing residues of the complex were kept flexible, disruption of the active association complex can be discerned. While docking of WA into segregated Hsp90 leaves the interface residues untouched. Thus the molecular docking analysis of WA into Hsp90 and active Hsp90/Cdc37 complex conducted in this study provides significant evidence in support of the proposed mechanism of chaperone assembly suppression by inhibition or disruption of active Hsp90/Cdc37 complex formation being accounted by non-assembly of the catalytically active Hsp90/Cdc37 complex. Results from the molecular dynamics simulations in water show that the trajectories of the protein complexed with ligand WA are stable over a considerably long time period of 4 ns, with the energies of the complex being lowered in comparison to the un-docked association complex, suggesting the thermodynamic stability of WA complexed Hsp90/Cdc37.. The molecular chaperone Hsp90 has been a promising target for cancer therapy. Cancer is a disease marked by genetic instability. Thus specific inhibition of individual proteins or signalling pathways holds a great potential for subversion of this genetic plasticity of cancers. This study is a step forward in this direction. Our computational analysis provided a rationalization to the ability of naturally occurring WA to alter the chaperone signalling pathway. The large value of binding energy involved in binding of WA to the active Hsp90/Cdc37 complex consolidates the thermodynamic stability of the binding. Our docking results obtained substantiate the hypothesis that WA has the potential to inhibit the association of chaperone (Hsp90) to its co-chaperone (Cdc37) by disrupting the stability of attachment of Hsp90 to Cdc37. Conclusively our results strongly suggest that withaferin A is a potent anticancer agent as ascertained by its potent Hsp90-client modulating capability.

    Topics: Algorithms; Antineoplastic Agents, Phytogenic; Cell Cycle Proteins; Chaperonins; Computational Biology; HSP90 Heat-Shock Proteins; Ligands; Molecular Dynamics Simulation; Neoplasms; Protein Binding; Protein Interaction Mapping; Withanolides

2011
Cytotoxicity of withanolides isolated from Acnistus arborescens.
    Fitoterapia, 2009, Volume: 80, Issue:6

    A new withanolide identified by spectroscopic analysis as 12beta-acetoxy-4-deoxy-5,6-deoxy-Delta(5)-withanolide D and Withanolide D, were isolated from the leaves of Acnistus arborescens. Cytotoxic activity of these two compounds against human tumor cell lines HT-29, MCF-7, MKN-45, HEp-2, HeLa, U-937 and two human normal fibroblast cultures, Fib04 and Fib05, were assessed. Withanolide D presented in vitro cytotoxic activity against tumor cell lines at the low micromolar range (LC(50):1.0 to 1.69 microM) and showed a slightly lower activity against Fib04, suggesting moderated selectivity among tumoral and normal cells. No cytotoxic effect was observed for 12beta-acetoxy-4-deoxy-5,6-deoxy-Delta(5)-withanolide D.

    Topics: 2S Albumins, Plant; Antineoplastic Agents, Phytogenic; Cell Line; Cell Line, Tumor; Ergosterol; Fibroblasts; HeLa Cells; Humans; Neoplasms; Phytotherapy; Plant Extracts; Solanaceae; Withanolides

2009
The tumor proteasome is a primary target for the natural anticancer compound Withaferin A isolated from "Indian winter cherry".
    Molecular pharmacology, 2007, Volume: 71, Issue:2

    Withaferin A (WA) is a steroidal lactone purified from medicinal plant "Indian Winter Cherry" that is widely researched for its variety of properties, including antitumor effects. However, the primary molecular target of WA is unknown. By chemical structure analysis, we hypothesized that Withaferin A might be a natural proteasome inhibitor. Computational modeling studies consistently predict that C1 and C24 of WA are highly susceptible toward a nucleophilic attack by the hydroxyl group of N-terminal threonine of the proteasomal chymotrypsin subunit beta5. Furthermore, WA potently inhibits the chymotrypsin-like activity of a purified rabbit 20S proteasome (IC50=4.5 microM) and 26S proteasome in human prostate cancer cultures (at 5-10 microM) and xenografts (4-8 mg/kg/day). Inhibition of prostate tumor cellular proteasome activity in cultures and in vivo by WA results in accumulation of ubiquitinated proteins and three proteasome target proteins (Bax, p27, and IkappaB-alpha) accompanied by androgen receptor protein suppression (in androgen-dependent LNCaP cells) and apoptosis induction. Treatment of WA under conditions of the aromatic ketone reduction, or reduced form of Celastrol, had significantly decreased the proteasome-inhibitory and apoptosis-inducing activities. Treatment of human prostate PC-3 xenografts with WA for 24 days resulted in 70% inhibition of tumor growth in nude mice, associated with 56% inhibition of the tumor tissue proteasomal chymotrypsinlike activity. Our results demonstrate that the tumor proteasome beta5 subunit is the primary target of WA, and inhibition of the proteasomal chymotrypsin-like activity by WA in vivo is responsible for, or contributes to, the antitumor effect of this ancient medicinal compound.

    Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Chymotrypsin; Ergosterol; Humans; Male; Mice; Mice, Nude; Models, Molecular; Neoplasms; Plants, Medicinal; Prostatic Neoplasms; Proteasome Endopeptidase Complex; Proteasome Inhibitors; Rabbits; Structure-Activity Relationship; Transplantation, Heterologous; Withanolides

2007