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Survivin, a member of the IAP family, functions as a homodimer and inhibits caspases, the key enzymes involved in apoptosis. Several Survivin inhibitors, including YM-155, Debio1143, EM1421, LQZ-7I, and TL32711, have emerged as potential anticancer drugs awaiting validation in clinical trials. Due to the high cost and adverse side effects of synthetic drugs, natural compounds with similar activity have also been in demand. In this study, we conducted molecular docking assays to evaluate the ability of Wi-A and Wi-N to block Survivin dimerization. We found that Wi-A, but not Wi-N, can bind to and prevent the homodimerization of Survivin, similar to YM-155. Therefore, we prepared a Wi-A-rich extract from Ashwagandha leaves (Wi-AREAL). Experimental analyses of human cervical carcinoma cells (HeLa and ME-180) treated with Wi-AREAL (0.05-0.1%) included assessments of viability, apoptosis, cell cycle, migration, invasion, and the expression levels (mRNA and protein) of molecular markers associated with these phenotypes. We found that Wi-AREAL led to growth arrest mediated by the upregulation of p21 WAF1 and the downregulation of several proteins (CDK1, Cyclin B, pRb) involved in cell cycle progression. Furthermore, Wi-AREAL treatment activated apoptosis signaling, as evidenced by reduced PARP-1 and Bcl-2 levels, increased procaspase-3, and elevated Cytochrome C. Additionally, treating cells with a nontoxic low concentration (0.01%) of Wi-AREAL inhibited migration and invasion, as well as EMT (epithelial-mesenchymal transition) signaling. By combining computational and experimental approaches, we demonstrate the potential of Wi-A and Wi-AREAL as natural inhibitors of Survivin, which may be helpful in cancer treatment.

Aim: Our goal was to investigate the use of Cyclodextrin in creating an aqueous extract of Cinnamon with a high content of its bioactive ingredients, validated by cell-based assays., Background: Due to their safety and cost-effectiveness, natural compounds have garnered attention for cancer therapy, which often faces challenges related to drug toxicity and resistance. Cinnamon (Cinnamomum verum; also known as Ceylon Cinnamon) is a commonly used spice with a history in folk medicine for treating various ailments. However, its active ingredients suffer from poor solubility, stability, and bioavailability, which limits its use and benefits., Objective: We prepared γCyclodextrin (γCD)-assisted aqueous extract of Cinnamon (CD-CIN) and compared its activity with the DMSO extract (DM-CIN)., Methods: The cells were exposed to CD-CIN and DM-CIN extracts under normal and stressed (oxidative, metal, and hypoxic) conditions and then analyzed for stress and cancerous phenotypes using various molecular assays., Results: We found that CD-CIN possesses considerable anticancer activity that involves the activation of tumor suppressor proteins and DNA damage response. Low, non-toxic concentrations of DM-CIN and CD-CIN caused comparable inhibition of migration and invasion capability of cells, supported by molecular marker analyses. Furthermore, protection against oxidative, metal, and hypoxia stress, as well as induction of differentiation, was recorded in both DM-CIN and CD-CIN treated cells, as compared to the control., Conclusion: We report CD-CIN as a new economic and easy Cinnamon-derived resource that possesses considerable anticancer and antistress activities and hence warrants further chemical, in vitro, and in vivo studies., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Chronic stress has been linked to a large number of pathologies, including cancer, premature aging, and neurodegenerative diseases. The accumulation of molecular waste resulting from oxidative and heavy metal-induced stress has been ascribed as a major factor contributing to these diseases. With this in mind, we started by screening 13 small molecules to determine their antistress potential in heavy metal stress-exposed C6 glioblastoma and found that alpha-lipoic acid (ALA) (a natural antioxidant abundantly present in yeast, spinach, broccoli, and meat) was the most effective candidate. We then conducted molecular analyses to validate its mechanism of action. Dose-dependent toxicity assays of cells treated with two ALA enantiomers, R-ALA and S-ALA, showed that they are nontoxic and can be tolerated at relatively high doses. Cells exposed to heavy metal, heat, and oxidative stress showed better recovery when cultured in R-ALA-/S-ALA-supplemented medium, supported by reduction of reactive oxygen species (ROS), aggregated proteins, and mitochondrial and deoxyribonucleic acid (DNA) damage. Molecular analyses revealed protection against stress-induced apoptosis and induction of autophagy in R-ALA- and S-ALA-treated C6/U2OS cells. Consistent with these findings, normal human fibroblasts showed lifespan extension. Taken together, this study demonstrates that lipoic acid has antiaging and antistress potential and warrants further attention in laboratory and clinical studies., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Mortalin, a member of the Hsp70 family of proteins, is commonly enriched in many types of cancers. It promotes carcinogenesis and metastasis in multiple ways of which the inactivation of the tumor suppressor activity of p53 has been firmly established. The downregulation of mortalin and/or disruption of mortalin-p53 interactions by small molecules has earlier been shown to activate p53 function yielding growth arrest/apoptosis in cancer cells. Mortaparibs (Mortaparib, Mortaparib Plus , and Mortaparib Mild ) are chemical inhibitors of mortalin isolated by cell-based two-way screening involving (i) a shift in the mortalin staining pattern from perinuclear (characteristics of cancer cells) to pancytoplasmic (characteristics of normal cells) and (ii) the nuclear enrichment of p53. They have similar structures and also cause the inhibition of PARP1 and hence were named Mortaparibs. In the present study, we report the anticancer and anti-metastasis activity of Mortaparib Mild (4-[(4-amino-5-thiophen-2-yl-1,2,4-triazol-3-yl)sulfanylmethyl]-N-(4-methoxyphenyl)-1,3-thiazol-2-amine) in p53-null cells. By extensive molecular analyses of cell proliferation, growth arrest, and apoptosis pathways, we demonstrate that although it causes relatively weaker cytotoxicity compared to Mortaparib and Mortaparib Plus , its lower concentrations were equally potent to inhibit cell migration. We developed combinations (called Mortaparib Mix-AP , Mortaparib Mix-AM , and Mortaparib Mix-AS ) consisting of different ratios of three Mortaparibs for specifically enhancing their anti-proliferation, anti-migration, and antistress activities, respectively. Based on the molecular analyses of control and treated cells, we suggest that the three Mortaparibs and their mixtures may be considered for further laboratory and clinical studies validating their use for the treatment of cancer as well as prevention of its relapse and metastasis.

Cancer metastasis, a highly complex process wherein cancer cells move from the primary site to other sites in the body, is a major hurdle in its therapeutics. A large array of synthetic chemotherapeutic molecules used for the treatment of metastatic cancers, besides being extremely expensive and unaffordable, are known to cause severe adverse effects leading to poor quality of life (QOL) of the patients. In this premise, natural compounds (considered safe, easily available and economic) that possess the potential to inhibit migration of cancer cells are deemed useful and hence are on demand. Cucurbitacin-B (19-(10→9β)-abeo-10-lanost-5-ene triterpene, called Cuc-B) is a steroid mostly found in plants of Cucurbitaceae family. It has been shown to possess anticancer activity although the molecular mechanism remains poorly defined. We present evidence that Cuc-B has the ability to interact with mortalin and HDM2 proteins that are enriched in cancer cells, suppress wild type p53 function and promote cancer cell migration. Computational analyses showed that Cuc-B interacts with mortalin similar to MKT077 and Withanone, both have been shown to reactivate p53 function and inhibit cell migration. Furthermore, Cuc-B interacted with HDM2 similar to Y30, a well-known inhibitor of HDM2. Experimental cell and molecular analyses demonstrated the downregulation of several proteins, critically involved in cell migration in Cuc-B (low non-toxic doses)-treated cancer cells and exhibited inhibition of cell migration. The data suggested that Cuc-B is a potential natural drug that warrants further mechanistic and clinical studies for its use in the management of metastatic cancers.Communicated by Ramaswamy H. Sarma.

Background: DNA methyltransferases (DNMTs) have been reported to be potential drug targets in various cancers. The major hurdle in inhibiting DNMTs is the lack of knowledge about different DNMTs and their role in the hypermethylation of gene promoters in cancer cells. Lack of information on specificity, stability, and higher toxicity of previously reported DNMT inhibitors is the major reason for inadequate epigenetic cancer therapy. DNMT1 and DNMT3A are the two DNMTs that are majorly overexpressed in cancers., Objective: In this study, we have presented computational and experimental analyses of the potential of some natural compounds, withaferin A (Wi-A), withanone (Wi-N), and caffeic acid phenethyl ester (CAPE), as DNMT inhibitors, in comparison to sinefungin (SFG), a known dual inhibitor of DNMT1 and DNMT3A., Methods: We used classical simulation methods, such as molecular docking and molecular dynamics simulations, to investigate the binding potential and properties of the test compounds with DNMT1 and DNMT3A. Cell culture-based assays were used to investigate the inactivation of DNMTs and the resulting hypomethylation of the p16 INK4A promoter, a key tumour suppressor that is inactivated by hypermethylation in cancer cells, resulting in upregulation of its expression., Results: Among the three test compounds (Wi-A, Wi-N, and CAPE), Wi-A showed the highest binding affinity to both DNMT1 and DNMT3A; CAPE showed the highest affinity to DNMT3A, and Wi-N showed a moderate affinity interaction with both. The binding energies of Wi-A and CAPE were further compared with SFG. Expression analysis of DNMTs showed no difference between control and treated cells. Cell viability and p16 INK4A expression analysis showed a dose-dependent decrease in viability, an increase in p16 INK4A , and a stronger effect of Wi-A compared to Wi-N and CAPE., Conclusion: The study demonstrated the differential binding ability of Wi-A, Wi-N, and CAPE to DNMT1 and DNMT3A, which was associated with their inactivation, leading to hypomethylation and desilencing of the p16 INK4A tumour suppressor in cancer cells. The test compounds, particularly Wi-A, have the potential for cancer therapy., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background: The recent COVID-19 (coronavirus disease 2019) pandemic triggered research on the development of new vaccines/drugs, repurposing of clinically approved drugs, and assessment of natural anti-COVID-19 compounds. Based on the gender difference in the severity of the disease, such as a higher number of men hospitalized and in intense care units, variations in sex hormones have been predicted to play a role in disease susceptibility. Cell surface receptors (Angiotensin-Converting Enzyme 2; ACE2 and a connected transmembrane protease serine 2- TMPSS2) are upregulated by androgens. Conversely, androgen antagonists have also been shown to lower ACE2 levels, implying their usefulness in COVID-19 management., Objectives: In this study, we performed computational and cell-based assays to investigate the anti- COVID-19 potential of Withaferin-A and Caffeic acid phenethyl ester, natural compounds from Withania somnifera and honeybee propolis, respectively., Methods: Structure-based computational approach was adopted to predict binding stability, interactions, and dynamics of the two test compounds to three target proteins (androgen receptor, ACE2, and TMPRSS2). Further, in vitro , cell-based experimental approaches were used to investigate the effect of compounds on target protein expression and SARS-CoV-2 replication., Results: Computation and experimental analyses revealed that (i) CAPE, but not Wi-A, can act as androgen antagonist and hence inhibit the transcriptional activation function of androgen receptor, (ii) while both Wi-A and CAPE could interact with ACE2 and TMPRSS2, Wi-A showed higher binding affinity, and (iii) combination of Wi-A and CAPE (Wi-ACAPE) caused strong downregulation of ACE2 and TMPRSS2 expression and inhibition of virus infection., Conclusion: Wi-A and CAPE possess multimodal anti-COVID-19 potential, and their combination (Wi-ACAPE) is expected to provide better activity and hence warrant further attention in the laboratory and clinic., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

SARS-CoV-2 viral infection is regulated by the host cell receptors ACE2 and TMPRSS2, and therefore the effect of various natural and synthetic compounds on these receptors has recently been the subject of investigations. Cyclodextrins, naturally occurring polysaccharides derived from starch, are soluble in water and have a hydrophobic cavity at their center enabling them to accommodate small molecules and utilize them as carriers in the food, supplements, and pharmaceutical industries to improve the solubility, stability, and bioavailability of target compounds. In the current study, computational molecular simulations were used to investigate the ability of α-, β- and γ-Cyclodextrins on human cell surface receptors. Cell-based experimental approaches, including expression analyses at mRNA and protein levels and virus replication, were used to assess the effect on receptor expression and virus infection, respectively. We found that none of the three CDs could dock effectively to human cell surface receptor ACE2 and viral protease M pro (essential for virus replication). On the other hand, α- and β-CD showed strong and stable interactions with TMPRSS2, and the expression of both ACE2 and TMPRSS2 was downregulated at the mRNA and protein levels in cyclodextrin (CD)-treated cells. A cell-based virus replication assay showed ∼20% inhibition by β- and γ-CD. Taken together, the study suggested that (i) downregulation of expression of host cell receptors may not be sufficient to inhibit virus infection (ii) activity of the receptors and virus protein M pro may play a critical and clinically relevant role, and hence (iii) newly emerging anti-Covid-19 compounds warrant multimodal functional analyses.Communicated by Ramaswamy H. Sarma.

A variety of environmental stress stimuli have been linked to poor quality of life, tissue dysfunctions, and ailments including metabolic disorders, cognitive impairment, and accelerated aging. Oxidative, metal, and hypoxia stresses are largely associated with these phenotypes. Whereas drug development and disease therapeutics have advanced remarkably in last 3 decades, there are still limited options for stress management. Because the latter can effectively decrease the disease burden, we performed cell-based screening of antistress compounds by recruiting 3 chemical models of oxidative (paraquat), metal (cadmium nitrate), or hypoxia (cobalt chloride) stresses. The screening of 70 compounds for their ability to offer protection against oxidative, metal, and hypoxia stresses resulted in the selection of 5 compounds: Withaferin-A (Wi-A), methoxy Withaferin-A (mWi-A), Withanone (Wi-N), triethylene glycol (TEG), and Ashwagandha (Withania somnifera) leaf M2-DMSO extract (M2DM). Molecular assays revealed that whereas stress caused increase in (a) apoptosis, (b) reactive oxygen species accumulation coupled with mitochondrial depolarization, (c) DNA double-strand breaks, and (d) protein aggregation, low nontoxic doses of the selected compounds caused considerable protection. Furthermore, Wi-N, TEG, and their mixture-treated normal human fibroblasts (at young, mature, and senescent stages representing progressively increasing accumulation of stress) showed increase in proliferation. Taken together, these results suggested 3-way (oxidative, metal, and hypoxia) antistress potential of Wi-N and TEG that may be useful for management of environmental and old-age-related pathologies., (© The Author(s) 2023. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Discovery of CARF (Collaborator of ARF)/CDKN2AIP as an ARF-interacting protein that promotes ARF-p53-p21 WAF1 signaling and cellular senescence, initially established its role in genomic stress. Multiple reports further unraveled its role in regulation of senescence, growth arrest, apoptosis, or malignant transformation of cells in response to a variety of stress conditions in cultured human cells. It has been established as an essential protein. Whereas CARF-compromised cells undergo apoptosis, its enrichment has been recorded in a variety of cancer cells and has been associated with malignant transformation. We earlier demonstrated its role in stress-induced cell phenotypes that ranged from growth arrest, apoptosis, or malignant transformation. In the present study, we assessed the molecular mechanism of quantitative impact of change in CARF expression level on these cell fates. Stress-induced changes in CARF expression were assessed quantitatively with proteins involved in proteotoxicity, oxidative, genotoxic, and cytotoxic stress. These comparative quantitative analyses confirmed that (i) CARF responds to diverse stresses in a quantitative manner, (ii) its expression level serves as a reliable predictive measure of cell fates (iii) it correlates more with the DNA damage and MDA levels than the oxidative and proteotoxic signatures and (iv) CARF-expression based quantitative assay may be recruited for stress diagnostic applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

SARS-CoV-2 outbreak in China in December 2019 and its spread as worldwide pandemic has been a major global health crisis. Extremely high infection and mortality rate has severely affected all sectors of life and derailed the global economy. While drug and vaccine development have been prioritized and have made significant progression, use of phytochemicals and herbal constituents is deemed as a low-cost, safer and readily available alternative. We investigated therapeutic efficacy of eight withanolides (derived from Ashwagandha) against the angiotensin-converting enzyme 2 (ACE2) proteins, a target cell surface receptor for SARS-CoV-2 and report results on the (i) computational analyses including binding affinity and stable interactions with ACE2, occupancy of ACE2 residues in making polar and nonpolar interactions with different withanolides/ligands and (2) in vitro mRNA and protein analyses using human cancer (A549, MCF7 and HSC3) cells. We found that among all withanolides, Withaferin-A, Withanone, Withanoside-IV and Withanoside-V significantly inhibited the ACE2 expression. Analysis of withanolides-rich aqueous extracts derived from Ashwagandha leaves and stem showed a higher ACE2 inhibitory potency of stem-derived extracts. Taken together, we demonstrated the inhibitory potency of Ashwagandha withanolides and its aqueous extracts against ACE2.Communicated by Ramaswamy H. Sarma.

Genetic mutations in p53 are frequently associated with many types of cancers that affect its stability and activity through multiple ways. The Ser46 residue present in the transactivation domain2 (TAD2) domain of p53 undergoes phosphorylation that blocks its degradation by MDM2 and leads to cell cycle arrest/apoptosis/necrosis upon intrinsic or extrinsic stresses. On the other hand, unphosphorylated p53 mutants escape cell arrest or death triggered by these molecular signaling axes and lead to carcinogenesis. Phosphorylation of Ser in the TAD2 domain of p53 mediates its interactions with transcription factor p62, yielding transcriptional activation of downstream pro-apoptotic genes. The p53 phosphorylation causes string-like elongated conformation that increases its binding affinity with the PH domain of p62. On the other hand, lack of phosphorylation causes helix-like motifs and low binding affinity to p62. We undertook molecular simulation analyses to investigate the potential of some natural small molecules (Withanone (Wi-N) & Withaferin-A (Wi-A) from Ashwagandha; Cucurbitacin-B (Cuc-B) from bitter Cucumber; and Caffeic acid phenethyl ester (CAPE) and Artepillin C (ARC) from honeybee propolis) to interact with p62-binding region of p53 and restore its wild-type activity. We found that Wi-N, Wi-A, and Cuc-B have the potential to restore p53-p62 interaction for phosphorylation-deficient p53 mutants. Wi-N, in particular, caused a reversal of the α-helical structure into an elongated string-like conformation similar to the wild-type p53. These data suggested the use of these natural compounds for the treatment of p53 Ser46 mutant harbouring cancers. We also compared the efficiency of Wi-N, Wi-A, Cuc-B, CAPE, and ARC to abrogate Mortalin-p53 binding resulting in nuclear translocation and reactivation of p53 function and provide experimental evidence to the computational analysis. Taken together, the use of these small molecules for reactivation of p53 in cancer cells is suggested., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)

Mortalin, a heat shock family protein enriched in cancer cells, is known to inactivate tumor suppressor protein p53. Abrogation of mortalin-p53 interaction and reactivation of p53 has been shown to trigger growth arrest/apoptosis in cancer cells and hence, suggested to be useful in cancer therapy. In this premise, we earlier screened a chemical library to identify potential disruptors of mortalin-p53 interaction, and reported two novel synthetic small molecules (5-[1-(4-methoxyphenyl) (1,2,3,4-tetraazol-5-yl)]-4-phenylpyrimidine-2-ylamine) and (4-[(1E)-2-(2-phenylindol-3-yl)-1-azavinyl]-1,2,4-triazole) called Mortaparib and Mortaparib Plus , respectively. These compounds were shown to possess anticancer activity that was mediated through targeting mortalin and PARP1 proteins, essential for cancer cell survival and proliferation. Here, we report characterization of the third compound, {4-[(4-amino-5-thiophen-2-yl-1,2,4-triazol-3-yl)sulfanylmethyl]-N-(4-methoxyphenyl)-1,3-thiazol-2-amine}, isolated in the same screening. Extensive computational and molecular analyses suggested that the new compound has the capability to interact with mortalin, p53, and PARP1. We provide evidence that this new compound, although required in high concentration as compared to the earlier two compounds (Mortaparib and Mortaparib Plus ) and hence called Mortaparib Mild , also downregulates mortalin and PARP1 expression and functions in multiple ways impeding cancer cell proliferation and migration characteristics. Mortaparib Mild is a novel candidate anticancer compound that warrants further experimental and clinical attention., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Meidinna, Shefrin, Sari, Zhang, Dhanjal, Kaul, Sundar and Wadhwa.)

Cancer is one of the leading causes of death worldwide, accounting for nearly 10 million deaths in 2020. Therefore, cancer therapy is a priority research field to explore the biology of the disease and identify novel targets for the development of better treatment strategies. Mortalin is a member of the heat shock 70 kDa protein family. It is enriched in several types of cancer and contributes to carcinogenesis in various ways, including inactivation of the tumor suppressor p53, deregulation of apoptosis, induction of epithelial-mesenchymal transition, and enhancement of cancer stemness. It has been studied extensively as a therapeutic target for cancer treatment, and several types of anti-mortalin molecules have been discovered that effectively suppress the tumor cell growth. In this review, we 1) provide a comprehensive sketch of the role of mortalin in tumor biology; 2) discuss various anti-mortalin molecules, including natural compounds, synthetic small molecules, peptides, antibodies, and nucleic acids, that have shown potential for cancer treatment in laboratory studies; and 3) provide future perspectives in cancer treatment., Competing Interests: Author C-OY is a founder and chief executive officer (CEO) of GeneMedicine, Co., Ltd. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Yoon, Wadhwa, Kaul and Yun.)

Withaferin A (Wi-A) and Caffeic Acid Phenethyl Ester (CAPE) are the bioactive ingredients of Ashwagandha ( Withania somnifera ) and propolis, respectively. Both of these natural compounds have been shown to possess anticancer activity. In the present study, we recruited a low dose of each of these compounds and developed a combination that exhibited remarkably potent anti-migratory and anti-angiogenic activities. Extensive molecular analyses including a cDNA array and expression analyses of the specific gene targets demonstrated that such activities are mediated through their effect on cell adhesion/tight junction proteins (Claudins, E-cadherin), inhibition of canonical Wnt/β-catenin signaling pathways and the consequent downregulation of EMT-signaling proteins (Vimentin, MMPs, VEGF and VEGFR) that play a critical role in cancer metastasis. The data supported that this novel combination of Wi-A and CAPE (Wi-ACAPE, containing 0.5 µM of Wi-A and 10 µM of CAPE) may be recruited for the treatment of metastatic and aggressive cancers and, hence, warrant further evaluation by recruiting a variety of experimental and clinical metastatic models.

Withaferin-A (Wi-A), a secondary metabolite extracted from Ashwagandha ( Withania somnifera ), has been shown to possess anticancer activity. However, the molecular mechanism of its action and the signaling pathways have not yet been fully explored. We performed an inverse virtual screening to investigate its binding potential to the catalytic site of protein kinases and identified ABL as a strong candidate. Molecular docking and molecular dynamics simulations were undertaken to investigate the effects on BCR-ABL oncogenic signaling that is constitutively activated yielding uncontrolled proliferation and inhibition of apoptosis in Chronic Myeloid Leukemia (CML). We found that Wi-A and its closely related withanolide, Withanone (Wi-N), interact at both catalytic and allosteric sites of the ABL. The calculated binding energies were higher in the case of Wi-A at catalytic site (-82.19 ± 5.48) and allosteric site (-67.00 ± 4.96) as compared to the clinically used drugs Imatinib (-78.11 ± 5.21) and Asciminib (-54.00 ± 6.45) respectively. Wi-N had a lesser binding energy (-42.11 ± 10.57) compared to Asciminib at the allosteric site. The interaction and conformational changes, subjected to ligand interaction, were found to be similar to the drugs Imatinib and Asciminib. The data suggested that Ashwagandha extracts containing withanolides, Wi-A and Wi-N may serve as natural drugs for the treatment of CML. Inhibition of ABL is suggested as one of the contributing factors of anti-cancer activity of Wi-A and Wi-N, warranting further in vitro and in vivo experiments.

Coronavirus disease 2019 (COVID-19) initiated in December 2019 in Wuhan, China and became pandemic causing high fatality and disrupted normal life calling world almost to a halt. Causative agent is a novel coronavirus called Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2/2019-nCoV). While new line of drug/vaccine development has been initiated world-wide, in the current scenario of high infected numbers, severity of the disease and high morbidity, repurposing of the existing drugs is heavily explored. Here, we used a homology-based structural model of transmembrane protease serine 2 (TMPRSS2), a cell surface receptor, required for entry of virus to the target host cell. Using the strengths of molecular docking and molecular dynamics simulations, we examined the binding potential of Withaferin-A (Wi-A), Withanone (Wi-N) and caffeic acid phenethyl ester to TPMRSS2 in comparison to its known inhibitor, Camostat mesylate. We found that both Wi-A and Wi-N could bind and stably interact at the catalytic site of TMPRSS2. Wi-N showed stronger interactions with TMPRSS2 catalytic residues than Wi-A and was also able to induce changes in its allosteric site. Furthermore, we investigated the effect of Wi-N on TMPRSS2 expression in MCF7 cells and found remarkable downregulation of TMPRSS2 mRNA in treated cells predicting dual action of Wi-N to block SARS-CoV-2 entry into the host cells. Since the natural compounds are easily available/affordable, they may even offer a timely therapeutic/preventive value for the management of SARS-CoV-2 pandemic. We also report that Wi-A/Wi-N content varies in different parts of Ashwagandha and warrants careful attention for their use.Communicated by Ramaswamy H. Sarma.

Development of drugs that are selectively toxic to cancer cells and safe to normal cells is crucial in cancer treatment. Evaluation of membrane permeability is a key metric for successful drug development. In this study, we have used in silico molecular models of lipid bilayers to explore the effect of phosphatidylserine (PS) exposure in cancer cells on membrane permeation of natural compounds Withaferin A (Wi-A), Withanone (Wi-N), Caffeic Acid Phenethyl Ester (CAPE) and Artepillin C (ARC). Molecular dynamics simulations were performed to compute permeability coefficients. The results indicated that the exposure of PS in cancer cell membranes facilitated the permeation of Wi-A, Wi-N and CAPE through a cancer cell membrane when compared to a normal cell membrane. In the case of ARC, PS exposure did not have a notable influence on its permeability coefficient. The presented data demonstrated the potential of PS exposure-based models for studying cancer cell selectivity of drugs.

Propolis, also known as bee-glue, is a resinous substance produced by honeybees from materials collected from plants they visit. It contains mixtures of wax and bee enzymes and is used by bees as a building material in their hives and by humans for different purposes in traditional healthcare practices. Although the composition of propolis has been shown to depend on its geographic location, climatic zone, and local flora; two largely studied types of propolis: (i) New Zealand and (ii) Brazilian green propolis have been shown to possess Caffeic Acid Phenethyl Ester (CAPE) and Artepillin C (ARC) as the main bioactive constituents, respectively. We have earlier reported that CAPE and ARC possess anticancer activities, mediated by abrogation of mortalin-p53 complex and reactivation of p53 tumor suppressor function. Like CAPE, Artepillin C (ARC) and the supercritical extract of green propolis (GPSE) showed potent anticancer activity. In this study, we recruited low doses of GPSE and ARC (that did not affect either cancer cell proliferation or migration) to investigate their antistress potential using in vitro cell based assays. We report that both GPSE and ARC have the capability to disaggregate metal- and heat-induced aggregated proteins. Metal-induced aggregation of GFP was reduced by fourfold in GPSE- as well as ARC-treated cells. Similarly, whereas heat-induced misfolding of luciferase protein showed 80% loss of activity, the cells treated with either GPSE or ARC showed 60-80% recovery. Furthermore, we demonstrate their pro-hypoxia (marked by the upregulation of HIF-1α) and neuro-differentiation (marked by differentiation morphology and upregulation of expression of GFAP, β-tubulin III, and MAP2). Both GPSE and ARC also offered significant protection against oxidative stress and, hence, may be useful in the treatment of old age-related brain pathologies.

Mutations in the tumor suppressor protein p53 is a prevalent feature in majority of cancers resulting in inactivation of its activities related to control of cell cycle progression and proliferation. p53 Y220C is one of the common hotspot mutations that causes decrease in its thermodynamic stability. Some small molecules have been shown to bind to the mutated site and restore its wild type thermodynamics and tumor suppressor function. In this study, we have explored the potential of caffeic acid phenethyl ester (CAPE-a bioactive compound from propolis) to interact with p53 Y220C and restore its wild type p53 (p53 wt ) transcription activation and tumor suppressor activities. We recruited computational methods, viz. molecular docking, molecular dynamics simulations and free energy calculations to study the interaction of CAPE at the mutation crevice and found that it has potential to restore p53 wt function of the p53 Y220C mutant similar to a previously described restoration molecule PK7242. We provide cell-based experimental evidence to these predictions and suggest CAPE as a potential natural drug for treatment of p53 Y220C mutant harboring cancers., (© 2021. The Author(s).)

Serine/threonine-protein kinase B-raf (BRAF) plays a significant role in regulating cell division and proliferation through MAPK/ERK pathway. The constitutive expression of wild-type BRAF (BRAF WT ) and its mutant forms, especially V600E (BRAF V600E ), has been linked to multiple cancers. Various synthetic drugs have been approved and are in clinical trials, but most of them are reported to become ineffective within a short duration. Therefore, combinational therapy involving multiple drugs are often recruited for cancer treatment. However, they lead to toxicity and adverse side effects. In this computational study, we have investigated three natural compounds, namely Withaferin-A (Wi-A), Withanone (Wi-N) and Caffeic Acid Phenethyl ester (CAPE) for anti-BRAF WT and anti-BRAF V600E activity. We found that these compounds could bind stably at ATP-binding site in both BRAF WT and BRAF V600E proteins. In-depth analysis revealed that these compounds maintained the active conformation of wild-type BRAF protein by inducing αC-helix-In, DFG-In, extended activation segment and well-aligned R-spine residues similar to already known drugs Vemurafenib (VEM), BGB283 and Ponatinib. In terms of binding energy, among the natural compounds, CAPE showed better affinity towards both wild-type and V600E mutant proteins than the other two compounds. These data suggested that CAPE, Wi-A and Wi-N have potential to block constitutive autophosphorylation of BRAF and hence warrant in vitro and in vivo experimental validation., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Authors.)

Coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus has become a global health emergency. Although new vaccines have been generated and being implicated, discovery and application of novel preventive and control measures are warranted. We aimed to identify compounds that may possess the potential to either block the entry of virus to host cells or attenuate its replication upon infection. Using host cell surface receptor expression (angiotensin-converting enzyme 2 (ACE2) and Transmembrane protease serine 2 (TMPRSS2)) analysis as an assay, we earlier screened several synthetic and natural compounds and identified candidates that showed ability to down-regulate their expression. Here, we report experimental and computational analyses of two small molecules, Mortaparib and MortaparibPlus that were initially identified as dual novel inhibitors of mortalin and PARP-1, for their activity against SARS-CoV-2. In silico analyses showed that MortaparibPlus, but not Mortaparib, stably binds into the catalytic pocket of TMPRSS2. In vitro analysis of control and treated cells revealed that MortaparibPlus caused down-regulation of ACE2 and TMPRSS2; Mortaparib did not show any effect. Furthermore, computational analysis on SARS-CoV-2 main protease (Mpro) that also predicted the inhibitory activity of MortaparibPlus. However, cell-based antiviral drug screening assay showed 30-60% viral inhibition in cells treated with non-toxic doses of either MortaparibPlus or Mortaparib. The data suggest that these two closely related compounds possess multimodal anti-COVID-19 activities. Whereas MortaparibPlus works through direct interactions/effects on the host cell surface receptors (ACE2 and TMPRSS2) and the virus protein (Mpro), Mortaparib involves independent mechanisms, elucidation of which warrants further studies., (© 2021 The Author(s).)

Withania somnifera (Ashwagandha) is used in Indian traditional medicine, Ayurveda, and is believed to have a variety of health-promoting effects. The molecular mechanisms and pathways underlying these effects have not yet been sufficiently explored. In this study, we investigated the effect of Ashwagandha extracts and their major withanolides (withaferin A and withanone) on muscle cell differentiation using C2C12 myoblasts. We found that withaferin A and withanone and Ashwagandha extracts possessing different ratios of these active ingredients have different effects on the differentiation of C2C12. Withanone and withanone-rich extracts caused stronger differentiation of myoblasts to myotubes, deaggregation of heat- and metal-stress-induced aggregated proteins, and activation of hypoxia and autophagy pathways. Of note, the Parkinson's disease model of Drosophila that possess a neuromuscular disorder showed improvement in their flight and climbing activity, suggesting the potential of Ashwagandha withanolides for the management of muscle repair and activity.

Brain and neuronal circuits constitute the most complex organ networks in human body. They not only control and coordinate functions of all other organs, but also represent one of the most-affected systems with stress, lifestyle and age. With global increase in aging populations, these neuropathologies have emerged as major concern for maintaining quality of life. Recent era has witnessed a surge in nutritional remediation of brain dysfunctions primarily by "nutraceuticals" that refer to functional foods and supplements with pharmacological potential. Specific dietary patterns with a balanced intake of carbohydrates, fatty acids, vitamins and micronutrients have also been ascertained to promote brain health. Dietary herbs and their phytochemicals with wide range of biological and pharmacological activities and minimal adverse effects have gained remarkable attention as neuro-nutraceuticals. Neuro-nutraceutical potentials of herbs are often expressed as effects on cognitive response, circadian rhythm, neuromodulatory, antioxidant and anti-inflammatory activities that are mediated by effects on gene expression, epigenetics, protein synthesis along with their turnover and metabolic pathways. Epidemiological and experimental evidence have implicated enormous applications of herbal supplementation in neurodegenerative and psychiatric disorders. The present review highlights the identification, experimental evidence and applications of some herbs including Bacopa monniera, Withania somnifera, Curcuma longa, Helicteres angustifolia, Undaria pinnatifida, Haematococcus pluvialis, and Vitis vinifera, as neuro-nutraceuticals., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Activation of a telomere length maintenance mechanism (TMM), including telomerase and alternative lengthening of telomeres (ALT), is essential for replicative immortality of tumor cells, although its regulatory mechanisms are incompletely understood. We conducted a microRNA (miRNA) microarray analysis on isogenic telomerase positive (TEP) and ALT cancer cell lines. Amongst nine miRNAs that showed difference in their expression in TEP and ALT cancer cells in array analysis, miR-708 was selected for further analysis since it was consistently highly expressed in a large panel of ALT cells. miR-708 in TEP and ALT cancer cells was not correlated with C-circle levels, an established feature of ALT cells. Its overexpression induced suppression of cell migration, invasion, and angiogenesis in both TEP and ALT cells, although cell proliferation was inhibited only in TEP cells suggesting that ALT cells may have acquired the ability to escape inhibition of cell proliferation by sustained miR-708 overexpression. Further, cell proliferation regulation in TEP cells by miR708 appears to be through the CARF-p53 pathway. We demonstrate here that miR-708 (i) is the first miRNA shown to be differentially regulated in TEP and ALT cancer cells, (ii) possesses tumor suppressor function, and (iii) deregulates CARF and p21 WAF1 -mediated signaling to limit proliferation in TEP cells., (© 2021. The Author(s).)

COVID-19 caused by SARS-CoV-2 corona virus has become a global pandemic. In the absence of drugs and vaccine, and premises of time, efforts and cost required for their development, natural resources such as herbs are anticipated to provide some help and may also offer a promising resource for drug development. Here, we have investigated the therapeutic prospective of Ashwagandha for the COVID-19 pandemic. Nine withanolides were tested in silico for their potential to target and inhibit (i) cell surface receptor protein (TMPRSS2) that is required for entry of virus to host cells and (ii) viral protein (the main protease M pro ) that is essential for virus replication. We report that the withanolides possess capacity to inhibit the activity of TMPRSS2 and M pro . Furthermore, withanolide-treated cells showed downregulation of TMPRSS2 expression and inhibition of SARS-CoV-2 replication in vitro, suggesting that Ashwagandha may provide a useful resource for COVID-19 treatment., (Copyright © 2021. Published by Elsevier B.V.)

Propolis is produced by honeybees from materials collected from plants they visit. It is a resinous material having mixtures of wax and bee enzymes. Propolis is also known as bee glue and used by bees as a building material in their hives, for blocking holes and cracks, repairing the combs and strengthening their thin borders. It has been extensively used since ancient times for different purposes in traditional human healthcare practices. The quality and composition of propolis depend on its geographic location, climatic zone and local flora. The New Zealand and Brazilian green propolis are the two main kinds that have been extensively studied in recent years. Their bioactive components have been found to possess a variety of therapeutic potentials. It was found that Brazilian green propolis improves the cognitive functions of mild cognitive impairments in patients living at high altitude and protects them from neurodegenerative damage through its antioxidant properties. It possesses artepillin C (ARC) as the key component, also known to possess anticancer potential. The New Zealand propolis contains caffeic acid phenethyl ester (CAPE) as the main bioactive with multiple therapeutic potentials. Our lab performed in vitro and in vivo assays on the extracts prepared from New Zealand and Brazilian propolis and their active ingredients. We provided experimental evidence that these extracts possess anticancer, antistress and hypoxia-modulating activities. Furthermore, their conjugation with γCD proved to be more effective. In the present review, we portray the experimental evidence showing that propolis has the potential to be a candidate drug for different ailments and improve the quality of life.

Withanolide derivatives have anticancer, anti-inflammatory, and other functions and are components of Indian traditional Ayurvedic medicine. Here, we found that 2,3-dihydro-3β-methoxy withaferin-A (3βmWi-A), a derivative of withaferin-A (Wi-A) belonging to a class of withanolides that are abundant in Ashwagandha ( Withania somnifera ), lengthened the period of the circadian clock. This compound dose-dependently elongated circadian rhythms in Sarcoma 180 cancer cells and in normal fibroblasts including NIH3T3 and spontaneously immortalized mouse embryonic fibroblasts (MEF). Furthermore, 3βmWi-A dose-dependently upregulated the mRNA expression and promoter activities of Bmal1 after dexamethasone stimulation and of the nuclear orphan receptors, Rora and Nr1d1 , that comprise the stabilization loop for Bmal1 oscillatory expression. We showed that 3βmWi-A functions as an inverse agonist for RORa with an IC50 of 11.3 μM and that 3βmWi-A directly, but weakly, interacts with RORa (estimated dissociation constant [ K d ], 5.9 μM). We propose that 3βmWi-A is a novel modulator of circadian rhythms.

The recent novel coronavirus, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2/2019-nCoV) has caused a large number of deaths around the globe. There is an urgent need to understand this new virus and develop prophylactic and therapeutic drugs. Since drug development is an expensive, intense and time-consuming path, timely repurposing of the existing drugs is often explored wherein the research avenues including genomics, bioinformatics, molecular modeling approaches offer valuable strengths. Here, we have examined the binding potential of Withaferin-A (Wi-A), Withanone (Wi-N) (active withanolides of Ashwagandha) and Caffeic Acid Phenethyl Ester (CAPE, bioactive ingredient of propolis) to a highly conserved protein, M pro of SARS-CoV-2. We found that Wi-N and CAPE, but not Wi-A, bind to the substrate-binding pocket of SARS-CoV-2 M pro with efficacy and binding energies equivalent to an already claimed N3 protease inhibitor. Similar to N3 inhibitor, Wi-N and CAPE were interacting with the highly conserved residues of the proteases of coronaviruses. The binding stability of these molecules was further analyzed using molecular dynamics simulations. The binding free energies calculated using MM/GBSA for N3 inhibitor, CAPE and Wi-N were also comparable. Data presented here predicted that these natural compounds may possess the potential to inhibit the functional activity of SARS-CoV-2 protease (an essential protein for virus survival), and hence (i) may connect to save time and cost required for designing/development, and initial screening for anti-COVID drugs, (ii) may offer some therapeutic value for the management of novel fatal coronavirus disease, (iii) warrants prioritized further validation in the laboratory and clinical tests.Communicated by Ramaswamy H. Sarma.

We previously performed a drug screening to identify a potential inhibitor of mortalin-p53 interaction. In four rounds of screenings based on the shift in mortalin immunostaining pattern from perinuclear to pan-cytoplasmic and nuclear enrichment of p53, we had identified Mortaparib Plus (4-[(1E)-2-(2-phenylindol-3-yl)-1-azavinyl]-1,2,4-triazole) as a novel synthetic small molecule. In order to validate its activity and mechanism of action, we recruited Luminal-A breast cancer cells, MCF-7 (p53 wild type ) and T47D (p53 L194F ) and performed extensive biochemical and immunocytochemical analyses. Molecular analyses revealed that Mortaparib Plus is capable of abrogating mortalin-p53 interaction in both MCF-7 and T47D cells. Intriguingly, upregulation of transcriptional activation function of p53 (as marked by upregulation of the p53 effector gene- p21 WAF1 -responsible for cell cycle arrest and apoptosis) was recorded only in Mortaparib Plus -treated MCF-7 cells. On the other hand, Mortaparib Plus -treated T47D cells exhibited hyperactivation of PARP1 (accumulation of PAR polymer and decrease in ATP levels) as a possible non-p53 tumor suppression program. However, these cells did not show full signs of either apoptosis or PAR-Thanatos. Molecular analyses attributed such a response to the inability of Mortaparib Plus to disrupt the AIF-mortalin complexes; hence, AIF did not translocate to the nucleus to induce chromatinolysis and DNA degradation. These data suggested that the cancer cells possessing enriched levels of such complexes may not respond to Mortaparib Plus . Taken together, we report the multimodal anticancer potential of Mortaparib Plus that warrants further attention in laboratory and clinical studies.

Cordyceps militaris possesses several compounds with medicinal properties, and is commonly used in traditional Chinese functional food and medicine for a variety of health benefits. Because of its rare occurrence in nature, the market demand for artificial C. militaris is on the rise. Furthermore, efforts to increase its bioactive ingredients have also been considered in research. In this study, we aimed to investigate the effect of fluoride on the growth and enrichment of bioactive compounds in C. militaris . A wide range of potassium fluoride concentrations (0, 0.001, 0.01, 0.1, and 1 mM) were added to the culture media as a source of fluoride during the cultivation of C. militaris fruiting bodies. The contents of fluorine and bioactive substances of the fruiting bodies in normal (NM) and fluorine-supplemented (FM) media were measured and compared. C. militaris raised in the growth medium supplemented with 0.01 mM potassium fluoride led to a 44.86% (1.55 ± 0.14 g/bottle) increase in biomass and a 23.43% (3161.38 ± 35.71 µg/g) increase in total carotenoid content in the fruiting bodies. Furthermore, a remarkable increase in superoxide dismutase-like activity (84.75 U/mg) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (IC 50 = 2.59 mg/mL) was recorded. In human cancer cell-based assays, C. militaris raised in FM caused stronger cytotoxicity, apoptosis, and cell cycle arrest in human osteosarcoma cells. These results demonstrated that a low dose of fluoride could stimulate the growth of C. militaris fruiting bodies and enhance the production of bioactive ingredients that possess useful antioxidant and anticancer activities.

p53 has an essential role in suppressing the carcinogenesis process by inducing cell cycle arrest/apoptosis/senescence. Mortalin/GRP75 is a member of the Hsp70 protein family that binds to p53 causing its sequestration in the cell cytoplasm. Hence, p53 cannot translocate to the nucleus to execute its canonical tumour suppression function as a transcription factor. Abrogation of mortalin-p53 interaction and subsequent reactivation of p53's tumour suppression function has been anticipated as a possible approach in developing a novel cancer therapeutic drug candidate. A chemical library was screened in a high-content screening system to identify potential mortalin-p53 interaction disruptors. By four rounds of visual assays for mortalin and p53, we identified a novel synthetic small-molecule triazole derivative (4-[(1E)-2-(2-phenylindol-3-yl)-1-azavinyl]-1,2,4-triazole, henceforth named Mortaparib Plus ). Its activities were validated using multiple bioinformatics and experimental approaches in colorectal cancer cells possessing either wild-type (HCT116) or mutant (DLD-1) p53. Bioinformatics and computational analyses predicted the ability of Mortaparib Plus to competitively prevent the interaction of mortalin with p53 as it interacted with the p53 binding site of mortalin. Immunoprecipitation analyses demonstrated the abrogation of mortalin-p53 complex formation in Mortaparib Plus -treated cells that showed growth arrest and apoptosis mediated by activation of p21 WAF1 , or BAX and PUMA signalling, respectively. Furthermore, we demonstrate that Mortaparib Plus -induced cytotoxicity to cancer cells is mediated by multiple mechanisms that included the inhibition of PARP1, up-regulation of p73, and also the down-regulation of mortalin and CARF proteins that play critical roles in carcinogenesis. Mortaparib Plus is a novel multimodal candidate anticancer drug that warrants further experimental and clinical attention.

Poor bioavailability due to the inability to cross the cell membrane is one of the major reasons for the failure of a drug in clinical trials. We have used molecular dynamics simulations to predict the membrane permeability of natural drugs-withanolides (withaferin-A and withanone) that have similar structures but remarkably differ in their cytotoxicity. We found that whereas withaferin-A, could proficiently transverse through the model membrane, withanone showed weak permeability. The free energy profiles for the interaction of withanolides with the model bilayer membrane revealed that whereas the polar head group of the membrane caused high resistance for the passage of withanone, the interior of the membrane behaves similarly for both withanolides. The solvation analysis further revealed that the high solvation of terminal O5 oxygen of withaferin-A was the major driving force for its high permeability; it interacted with the phosphate group of the membrane that led to its smooth passage across the bilayer. The computational predictions were tested by raising and recruiting unique antibodies that react to withaferin-A and withanone. The time-lapsed analyses of control and treated cells demonstrated higher permeation of withaferin-A as compared to withanone. The concurrence between the computation and experimental results thus re-emphasised the use of computational methods for predicting permeability and hence bioavailability of natural drug compounds in the drug development process.

The anticancer activities of Withaferin-A (Wi-A) and Withanone (Wi-N) from Ashwagandha and Caffeic Acid Phenethyl Ester (CAPE) from honeybee propolis have been well documented. Here, we examined the binding potential of these natural compounds to inhibit the constitutive phosphorylation of epidermal growth factor receptors (EGFRs). Exon 20 insertion mutants of EGFR, which show resistance to various FDA approved drugs and are linked to poor prognosis of lung cancer patients, were the primary focus of this study. Apart from exon 20 insertion mutants, the potential of natural compounds to serve as ATP competitive inhibitors of wildtype protein and other common mutants of EGFR, namely L858R and exon19del, were also examined. The potential of natural compounds was compared to the positive controls such as erlotinib, TAS6417 and poziotinib. Similar to known inhibitors, Wi-A and Wi-N could displace and binds at the ATP orthosteric site of exon19del, L858R and exon20, while CAPE was limited to wildtype EGFR and exon 20 insertion mutants only. Moreover, the binding free energy of the natural drugs against EGFRs was also comparable to the positive controls. This computational study suggests that Wi-A and Wi-N have potential against multiple mutated EGFRs, warranting further in vitro and in vivo experiments.

Cell-based screening of bioactive compounds has served as an important gateway in drug discovery. In the present report, using human neuroblastoma cells and enrolling an extensive three-step screening of 57 phytochemicals, we have identified caffeic acid phenethyl ester (CAPE) as a potent neurodifferentiating natural compound. Analyses of control and CAPE-induced neurodifferentiated cells revealed: (i) modulation of several key proteins (NF200, MAP-2, NeuN, PSD95, Tuj1, GAP43, and GFAP) involved in neurodifferentiation process; and (ii) attenuation of neuronal stemness (HOXD13, WNT3, and Msh-2) and proliferation-promoting (CDC-20, CDK-7, and BubR1) proteins. We anticipated that the neurodifferentiation potential of CAPE may be beneficial for the treatment of neurodegenerative diseases and tested it using the Drosophila model of Alzheimer's disease (AD) and mice model of amnesia/loss of memory. In both models, CAPE exhibited improved disease symptoms and activation of physiological functions. Remarkably, CAPE-treated mice showed increased levels of neurotrophin-BDNF, neural progenitor marker-Nestin, and differentiation marker-NeuN, both in the cerebral cortex and hippocampus. Taken together, we demonstrate the differentiation-inducing and therapeutic potential of CAPE for neurodegenerative diseases., (Copyright © 2020 Konar, Kalra, Chaudhary, Nayak, Guruprasad, Satyamoorthy, Ishida, Terao, Kaul and Wadhwa.)

Caffeic acid phenethyl ester (CAPE) is a key bioactive ingredient of honeybee propolis and is claimed to have anticancer activity. Since mortalin, a hsp70 chaperone, is enriched in a cancerous cell surface, we recruited a unique cell internalizing anti-mortalin antibody (MotAb) to generate mortalin-targeting CAPE nanoparticles (CAPE-MotAb). Biophysical and biomolecular analyses revealed enhanced anticancer activity of CAPE-MotAb both in in vitro and in vivo assays. We demonstrate that CAPE-MotAb cause a stronger dose-dependent growth arrest/apoptosis of cancer cells through the downregulation of Cyclin D1-CDK4, phospho-Rb, PARP-1, and anti-apoptotic protein Bcl2. Concomitantly, a significant increase in the expression of p53, p21 WAF1 , and caspase cleavage was obtained only in CAPE-MotAb treated cells. We also demonstrate that CAPE-MotAb caused a remarkably enhanced downregulation of proteins critically involved in cell migration. In vivo tumor growth assays for subcutaneous xenografts in nude mice also revealed a significantly enhanced suppression of tumor growth in the treated group suggesting that these novel CAPE-MotAb nanoparticles may serve as a potent anticancer nanomedicine.

Strategies for eradicating cancer stem cells (CSCs) are urgently required because CSCs are resistant to anticancer drugs and cause treatment failure, relapse and metastasis. Here, we show that photoactive functional nanocarbon complexes exhibit unique characteristics, such as homogeneous particle morphology, high water dispersibility, powerful photothermal conversion, rapid photoresponsivity and excellent photothermal stability. In addition, the present biologically permeable second near-infrared (NIR-II) light-induced nanocomplexes photo-thermally trigger calcium influx into target cells overexpressing the transient receptor potential vanilloid family type 2 (TRPV2). This combination of nanomaterial design and genetic engineering effectively eliminates cancer cells and suppresses stemness of cancer cells in vitro and in vivo. Finally, in molecular analyses of mechanisms, we show that inhibition of cancer stemness involves calcium-mediated dysregulation of the Wnt/β-catenin signalling pathway. The present technological concept may lead to innovative therapies to address the global issue of refractory cancers.

The anti-metastatic and anti-angiogenic activities of triethylene glycol derivatives have been reported. In this study, we investigated their molecular mechanism(s) using bioinformatics and experimental tools. By molecular dynamics analysis, we found that (i) triethylene glycol dimethacrylate (TD-10) and tetraethylene glycol dimethacrylate (TD-11) can act as inhibitors of the catalytic domain of matrix metalloproteinases (MMP-2, MMP-7 and MMP-9) by binding to the S1' pocket of MMP-2 and MMP-9 and the catalytic Zn ion binding site of MMP-7, and that (ii) TD-11 can cause local disruption of the secondary structure of vascular endothelial growth factor A (VEGFA) dimer and exhibit stable interaction at the binding interface of VEGFA receptor R1 complex. Cell-culture-based in vitro experiments showed anti-metastatic phenotypes as seen in migration and invasion assays in cancer cells by both TD-10 and TD-11. Underlying biochemical evidence revealed downregulation of VEGF and MMPs at the protein level; MMP-9 was also downregulated at the transcriptional level. By molecular analyses, we demonstrate that TD-10 and TD-11 target stress chaperone mortalin at the transcription and translational level, yielding decreased expression of vimentin, fibronectin and hnRNP-K, and increase in extracellular matrix (ECM) proteins (collagen IV and E-cadherin) endorsing reversal of epithelial-mesenchymal transition (EMT) signaling.

Cancer, an uncontrolled proliferation syndrome, is treated with synthetic chemotherapeutic drugs that are associated with severe adverse effects. Development and application of new natural compounds is warranted to deal with the exponentially increasing incidence of cancer worldwide. Keeping selective toxicity to cancer cells as a priority criterion, we developed a combination of Cucurbitacin B and Withanone, and analyzed its anticancer potential using non-small cell lung cancer cells. We demonstrate that the selective cytotoxicity of the combination, called CucWi-N, to cancer cells is mediated by induction of cellular senescence that was characterized by decrease in Lamin A/C, CDK2, CDK4, Cyclin D, Cyclin E, phosphorylated RB, mortalin and increase in p53 and CARF proteins. It compromised cancer cell migration that was mediated by decrease in mortalin, hnRNP-K, vascular endothelial growth factor, matrix metalloproteinase 2, and fibronectin. We provide in silico, molecular dynamics and experimental data to support that CucWi-N (i) possesses high capability to target mortalin-p53 interaction and hnRNP-K proteins, (ii) triggers replicative senescence and inhibits metastatic potential of the cancer cells, and (iii) inhibits tumor progression and metastasis in vivo. We propose that CucWi-N is a potential natural anticancer drug that warrants further mechanistic and clinical studies., (© The Author(s) 2019. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

We have earlier reported anticancer activity in Withaferin A (Wi-A), a withanolide derived from Ashwagandha ( Withania somnifera ) and caffeic acid phenethyl ester (CAPE), an active compound from New Zealand honeybee propolis. Whereas Wi-A was cytotoxic to both cancer and normal cells, CAPE has been shown to cause selective death of cancer cells. In the present study, we investigated the efficacy of Wi-A, CAPE, and their combination to ovarian and cervical cancer cells. Both Wi-A and CAPE were seen to activate tumor suppressor protein p53 by downregulation of mortalin and abrogation of its interactions with p53. Downregulation of mortalin translated to compromised mitochondria integrity and function that affected poly ADP-ribose polymerase1 (PARP1); a key regulator of DNA repair and protein-target for Olaparib, drugs clinically used for treatment of breast, ovarian and cervical cancers)-mediated DNA repair yielding growth arrest or apoptosis. Furthermore, we also compared the docking capability of Wi-A and CAPE to PARP1 and found that both of these could bind to the catalytic domain of PARP1, similar to Olaparib. We provide experimental evidences that (i) Wi-A and CAPE cause inactivation of PARP1-mediated DNA repair leading to accumulation of DNA damage and activation of apoptosis signaling by multiple ways, and (ii) a combination of Wi-A and CAPE offers selective toxicity and better potency to cancer cells.

CARF (Collaborator of ARF) was discovered as an ARF-interacting protein that activated ARF-p53-p21 WAF1 signaling involved in cellular response to a variety of stresses, including oxidative, genotoxic, oncogenic, or telomere deprotection stresses, leading to senescence, growth arrest, or apoptosis. Of note, whereas suppression of CARF was lethal, its enrichment was associated with increased proliferation and malignant transformation of cells. These reports have predicted that CARF could serve as a multi-stress marker with a predictive value for cell fates. Here, we recruited various in vitro stress models and examined their effect on CARF expression using human normal fibroblasts. We demonstrate that CARF levels in stress and post-stress conditions could predict the fate of cells towards either death or enhanced proliferation and malignant transformation. We provide extensive molecular evidence that (i) CARF expression changes in response to stress, (ii) it modulates cell death or survival signaling and determines the fate of cells, and (iii) it may serve as a predictive measure of cellular response to stress and an important marker for biosafety.

We screened some phytochemicals for cytotoxic activity to human cancer cells and identified Soyasapogenol-A (Snol-A) as a potent candidate anti-cancer compound. Interestingly, Soyasapogenin-I (Snin-I) was ineffective. Viability assays endorsed toxicity of Snol-A to a wide variety of cancer cells. Of note, wild type p53 deficient cancer cells (SKOV-3 and Saos-2) also showed potent growth inhibitory effect. Molecular analyses demonstrated that it targets CARF yielding transcriptional upregulation of p21 WAF1 (an inhibitor of cyclin-dependent kinases) and downregulation of its effector proteins, CDK2, CDK-4, Cyclin A and Cyclin D1. Targeting of CARF by Snol-A also caused (i) downregulation of pATR-Chk1 signaling leading to caspase-mediated apoptosis and (ii) inactivation of β-catenin/Vimentin/hnRNPK-mediated EMT signaling resulting in decrease in migration and invasion of cancer cells. In in vivo assays, Snol-A caused suppression of tumor growth in subcutaneous xenograft model and inhibited lung metastasis in tail vein injection model. Taken together, we demonstrate that Snol-A is a natural inhibitor of CARF and may be recruited as a potent anti-tumor and anti-metastasis compound for treatment of p53-deficient aggressive malignancies.

Environmental stress, exhaustive industrialization and the use of chemicals in our daily lives contribute to increasing incidence of cancer and other pathologies. Although the cancer treatment has revolutionized in last 2-3 decades, shortcomings such as (i) extremely high cost of treatment, (ii) poor availability of drugs, (iii) severe side effects and (iv) emergence of drug resistance have prioritized the need of developing alternate natural, economic and welfare (NEW) therapeutics reagents. Identification and characterization of such anti-stress NEW drugs that not only limit the growth of cancer cells but also reprogram them to perform their specific functions are highly desired. We recruited rat glioma- and human neuroblastoma-based assays to explore such activities of resveratrol, a naturally occurring stilbenoid. We demonstrate that nontoxic doses of resveratrol protect cells against a variety of stresses that are largely involved in age-related brain pathologies. These included oxidative, DNA damage, metal toxicity, heat, hypoxia, and protein aggregation stresses. Furthermore, it caused differentiation of cells to functional astrocytes and neurons as characterized by the upregulation of their specific protein markers. These findings endorse multiple bioactivities of resveratrol and encourage them to be tested for their benefits in animal models and humans.