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Phytochemicals have attracted attention in the oncological field because they are biologically friendly and have relevant pharmacological activities. Thanks to the intense and unique spicy aroma, garlic is one of the most used plants for cooking. Its consumption is correlated to health beneficial effects towards several chronic diseases, such as cancer, mainly attributable to allicin, a bioactive sulfur compound stored in different plant parts in a precursor form. The objective of this review is to present and critically discuss the chemistry and biosynthesis of allicin, its pharmacokinetic profile, its anticancer mechanisms and molecular targets, and its selectivity towards tumor cells. The research carried out so far revealed that allicin suppresses the growth of different types of tumors. In particular, it targets many signaling pathways associated with cancer development. Future research directions are also outlined to further characterize this promising natural product.

Breast Cancer (BC) is a leading cause of death in women, currently affecting 13% of female population worldwide. First-line clinical treatments against Estrogen Receptor positive (ER+) BC rely on suppressing estrogen production, by inhibiting the aromatase (AR) enzyme, or on blocking estrogen-dependent pro-oncogenic signaling, by targeting Estrogen Receptor (ER) α with selective Modulators/Degraders (SERMs/SERDs). The development of dual acting molecules targeting AR and ERα represents a tantalizing alternative strategy to fight ER + BC, reducing the incidence of adverse effects and resistance onset that limit the effectiveness of these gold-standard therapies. Here, in silico design, synthesis, biological evaluation and an atomic-level characterization of the binding and inhibition mechanism of twelve structurally related drug-candidates enable the discovery of multiple compounds active on both AR and ERα in the sub-μM range. The best drug-candidate 3a displayed a balanced low-nanomolar IC50 towards the two targets, SERM activity and moderate selectivity towards a BC cell line. Moreover, most of the studied compounds reduced ERα levels, suggesting a potential SERD activity. This study dissects the key structural traits needed to obtain optimal dual acting drug-candidates, showing that multitarget compounds may be a viable therapeutic option to counteract ER + BC.

A series of new Knoevenagel adducts, bearing two indolinone systems, has been synthesized and evaluated on 60 human cancer cell lines according to protocols available at the National Cancer Institute (Bethesda, MD, USA). Some derivatives proved to be potent antiproliferative agents, showing GI50 values in the submicromolar range. Compound 5b emerged as the most active and was further studied in Jurkat cells in order to determine the effects on cell-cycle phases and the kind of cell death induced. Finally, oxidative stress and DNA damage induced by compound 5b were also analyzed.

Proteasome inhibition represents an important anticancer strategy. Here, we studied the mechanisms at the basis of the pro-apoptotic activity of the standardized decoction of Hemidesmus indicus, a plant evoking a complex anticancer activity, and explored its inhibition of proteasome activity in human leukemia cells. Additionally, we preliminary tested the cytotoxicity of some H. indicus’s phytochemicals on leukemia cells and their intestinal absorption on a human intestinal epithelium model consisting of a monolayer of differentiated Caco2 cells. We observed a potent antileukemic effect for H. indicus, imputable to the modulation of different critical targets at protein and mRNA levels and the reduction of the 26S proteasome expression. We found that some phytomarkers of H. indicus decoction passed through the enterocyte monolayer. Overall, our study supports the pharmacological potential of H. indicus, which can represent an interesting botanical drug in the oncological area.

The marine environment is important yet generally underexplored. It contains new sources of functional constituents that can affect various pathways in food processing, storage, and fortification. Bioactive secondary metabolites produced by marine microorganisms may have significant potential applications for humans. Various components isolated from disparate marine microorganisms, including fungi, microalgae, bacteria, and myxomycetes, showed considerable biological effects, such as anticancer, antioxidant, antiviral, antibacterial, and neuroprotective activities. Growing studies are revealing that potential anticancer effects of marine agents could be achieved through the modulation of several organelles. Mitochondria are known organelles that influence growth, differentiation, and death of cells via influencing the biosynthetic, bioenergetic, and various signaling pathways related to oxidative stress and cellular metabolism. Consequently, mitochondria play an essential role in tumorigenesis and cancer treatments by adapting to alterations in environmental and cellular conditions. The growing interest in marine-derived anticancer agents, combined with the development and progression of novel technology in the extraction and cultures of marine life, led to revelations of new compounds with meaningful pharmacological applications. This is the first critical review on marine-derived anticancer agents that have the potential for targeting mitochondrial function during tumorigenesis. This study aims to provide promising strategies in cancer prevention and treatment.

The marine ecosystem, populated by a myriad of animals, plants, and microorganisms, is an inexhaustible reservoir of pharmacologically active molecules. Among the multiple secondary metabolites produced by marine sources, there are anthraquinones and their derivatives. Besides being mainly known to be produced by terrestrial species, even marine organisms and the uncountable kingdom of marine microorganisms biosynthesize anthraquinones. Anthraquinones possess many different biological activities, including a remarkable antitumor activity. However, due to their peculiar chemical structures, anthraquinones are often associated with toxicological issues, even relevant, such as genotoxicity and mutagenicity. The aim of this review is to critically describe the anticancer potential of anthraquinones derived from marine sources and their genotoxic and mutagenic potential. Marine-derived anthraquinones show a promising anticancer potential, although clinical studies are missing. Additionally, an in-depth investigation of their toxicological profile is needed before advocating anthraquinones as a therapeutic armamentarium in the oncological area.

Introduction Chemoprevention of cancer refers to the use of natural or synthetic compounds to abolish or perturb a variety of steps in tumor initiation, promotion, and progression. This can be realized through different mechanisms, including activation of free radical scavenging enzymes, control of chronic inflammation, and downregulation of specific signaling pathways. Areas covered The goal of this article is to critically review recent evidence on association between coffee and prevention of different types of cancer, with particular emphasis on the molecular mechanisms and the bioactive compounds involved in its anticancer activity. Expert opinion Coffee is a mixture of different compounds able to decrease the risk of many types of cancer. However, its potential anticancer activity is not completely understood. Hundreds of biologically active components such as caffeine, chlorogenic acid, diterpenes are contained in coffee. Further research is needed to fully elucidate the molecular mechanisms underlying the anticancer effects of coffee and fully understand the role of different confounding factors playing a role in its reported anticancer activity.

Cancer is at present one of the utmost deadly diseases worldwide. Past efforts in cancer research have focused on natural medicinal products. Over the past decades, a great deal of initiatives was invested towards isolating and identifying new marine metabolites via pharmaceutical companies, and research institutions in general. Secondary marine metabolites are looked at as a favorable source of potentially new pharmaceutically active compounds, having a vast structural diversity and diverse biological activities; therefore, this is an astonishing source of potentially new anticancer therapy. This review contains an extensive critical discussion on the potential of marine microbial compounds and marine microalgae metabolites as anticancer drugs, highlighting their chemical structure and exploring the underlying mechanisms of action. Current limitation, challenges, and future research pathways were also presented.

The burden of neoplastic diseases is widely recognized as a severe cause of mortality. The clinical inadequacy of most anticancer therapeutics urgently prompted intense drug discovery efforts toward the identification of new chemical entities endowed with a potent and safe antitumor profile. In this scenario, targeting cancer cells apoptosis machinery has emerged as a relevant strategy, useful for tackling the emergence of drug resistance. On this basis, a small library of naturally inspired hybrid molecules was obtained by combining, through a click chemistry approach, &ldquo, privileged&rdquo, synthons such as curcumin scaffold and 1,2,3-triazole building block. Compound 1, bearing a para-fluoro phenyl moiety, showed low-micromolar potency against T acute lymphoblastic leukemia cell growth. More in-depth biologic studies demonstrated, for this analog, cell death-inducing properties associated with its capability to simultaneously activate both the receptor and the mitochondrial apoptosis cascades. This peculiar behavior offers promises for achieving an expanded anticancer effect, namely intense cytotoxic response coupled with reduced predisposition of chemoresistance insurgence. Altogether, this study allowed the identification of compound 1 as a lead compound worth to be progressed as an anticancer drug candidate.

Drugs targeting human topoisomerase II (topoII) are used in clinical practice since decades. Nevertheless, there is an urgent need for new and safer topoII inhibitors due to the emergence of secondary malignancies and the appearance of resistance mechanisms upon treatment with topoII-targeted anticancer drugs. In the present investigation, we report the discovery of a new topoII inhibitor, whose design was based on the structure of the natural product trypthantrin, a natural alkaloid containing a basic indoloquinazoline moiety. This new topoII inhibitor, here numbered compound 5, is found to inhibit topoII with an IC50 of 26.6 ± 4.7 μM. Notably, compound 5 is more potent than the template compound trypthantrin, and even than the widely used topoII-targeted clinical drug etoposide. In addition, compound 5 also exhibits high water solubility, and a promising antiproliferative activity on different tumor cell lines such as acute leukemia, colon, and breast cancer. In light of these results, compound 5 represents a promising lead for developing new topoII inhibitors as anti-cancer therapeutic agents.

Often, even the most effective antineoplastic drugs currently used in clinic do not efficiently allow complete healing due to the related toxicity. The reason for the toxicity lies in the lack of selectivity for cancer cells of the vast majority of anticancer agents. Thus, the need for new potent anticancer compounds characterized by a better toxicological profile is compelling. Lectins belong to a particular class of non-immunogenic glycoproteins and have the characteristics to selectively bind specific sugar sequences on the surface of cells. This property is exploited to exclusively bind cancer cells and exert antitumor activity through the induction of different forms of regulated cell death and the inhibition of cancer cell proliferation. Thanks to the extraordinary biodiversity, marine environments represent a unique source of active natural compounds with anticancer potential. Several marine and freshwater organisms, ranging from the simplest alga to the most complex vertebrate, are amazingly enriched in these proteins. Remarkably, all studies gathered in this review show the impressive anticancer effect of each studied marine lectin combined with irrelevant toxicity in vitro and in vivo and pave the way to design clinical trials to assess the real antineoplastic potential of these promising proteins. It provides a concise and precise description of the experimental results, their interpretation as well as the experimental conclusions that can be drawn.

The inhibition of steroidogenic cytochrome P450 enzymes has been shown to play a central role in the management of life-threatening diseases such as cancer, and indeed potent inhibitors of CYP19 (aromatase) and CYP17 (17α hydroxylase/17,20 lyase) are currently used for the treatment of breast, ovarian and prostate cancer. In the last few decades CYP11B1 (11-β-hydroxylase) and CYP11B2 (aldosterone synthase), key enzymes in the biosynthesis of cortisol and aldosterone, respectively, have been also investigated as targets for the identification of new potent and selective agents for the treatment of Cushing's syndrome, impaired wound healing and cardiovascular diseases. In an effort to improve activity and synthetic feasibility of our different series of xanthone-based CYP11B1 and CYP11B2 inhibitors, a small series of imidazolylmethylbenzophenone-based compounds, previously reported as CYP19 inhibitors, was also tested on these new targets, in order to explore the role of a more flexible scaffold for the inhibition of CYP11B1 and -B2 isoforms. Compound 3 proved to be very potent and selective towards CYP11B1, and was thus selected for further optimization via appropriate decoration of the scaffold, leading to new potent 4'-substituted derivatives. In this second series, 4 and 8, carrying a methoxy group and a phenyl ring, respectively, proved to be low-nanomolar inhibitors of CYP11B1, despite a slight decrease in selectivity against CYP11B2. Moreover, unlike the benzophenones of the first series, the 4'-substituted derivatives also proved to be selective for CYP11B enzymes, showing very weak inhibition of CYP19 and CYP17. Notably, the promising result of a preliminary scratch test performed on compound 8 confirmed the potential of this compound as a wound-healing promoter.

In the cold environments of the interstellar medium, a variety of molecules in which a hydrogen (H) atom has been replaced by its heavier isotope deuterium (D) can be found. From its emergence, life had to counteract the toxic action of many agents, which posed a constant threat to its development and propagation. Oxygen-reactive species are archaic toxicants that lead to protein damage and genomic instability. Most of the oxidative lesions involve cleavage of C-H bonds and H abstraction. According to free radical chemistry principles, the substitution of D for H in oxidation-sensitive positions of cellular components should confer protection against the oxidative attack without compromising the chemical identity of the compounds. Here, we show that deuterated nucleosides and proteins protect from oxidative damage. Our data suggest a new, subtle but likely role of D in terrestrial life’s evolution in that its inclusion in critical biomolecules might have facilitated their resistance during the infinite generations of life entities, cells, and organisms.

Every day, we come into contact with ultraviolet radiation (UVR). If under medical supervision, small amounts of UVR could be beneficial, the detrimental and hazardous effects of UVR exposure dictate an unbalance towards the risks on the risk-benefit ratio. Acute and chronic effects of ultraviolet-A and ultraviolet-B involve mainly the skin, the immune system, and the eyes. Photodamage is an umbrella term that includes general phototoxicity, photoaging, and cancer caused by UVR. All these phenomena are mediated by direct or indirect oxidative stress and inflammation and are strictly connected one to the other. Astaxanthin (ASX) and fucoxanthin (FX) are peculiar marine carotenoids characterized by outstanding antioxidant properties. In particular, ASX showed exceptional efficacy in counteracting all categories of photodamages, in vitro and in vivo, thanks to both antioxidant potential and activation of alternative pathways. Less evidence has been produced about FX, but it still represents an interesting promise to prevent the detrimental effect of UVR. Altogether, these results highlight the importance of digging into the marine ecosystem to look for new compounds that could be beneficial for human health and confirm that the marine environment is as much as full of active compounds as the terrestrial one, it just needs to be more explored.

Alkaloids are important chemical compounds that serve as a rich source for drug discovery. Numerous alkaloids screened from medicinal plants and herbs showed antiproliferative and anticancer effects on wide category of cancers both in vitro and in vivo. Vinblastine, vinorelbine, vincristine, and vindesine have already been successfully developed as anticancer drugs. The available and up-to-date information on the ethnopharmacological uses in traditional medicine, phytochemistry, pharmacology and clinical utility of alkaloids were collected using various resources (PubMed, ScienceDirect, Google Scholar and Springerlink). In this article, we provide a comprehensive and critical overview on naturally-occurring alkaloids with anticancer activities and highlight the molecular mechanisms of action of these secondary metabolites. Furthermore, this review also presents a summary of synthetic derivatives and pharmacological profiles useful to researchers for the therapeutic development of alkaloids. Based on the literature survey compiled in this review, alkaloids represent an important group of anticancer drugs of plant origin with enormous potential for future development of drugs for cancer therapy and management.

Breast cancer is the most diagnosed type of cancer among women for which an exhaustive cure has not been discovered yet. Nowadays, tamoxifen still represents the gold standard for breast cancer therapy; it acts on both estrogen receptor-positive and estrogen receptor-negative breast cancers. Unfortunately, its toxicity and the related chemoresistance undermine its antitumor potential. In this paper, new tamoxifen-based derivatives with a rigid structural motif in their structure were designed, synthesized, and evaluated to assess their antitumor behavior. All the tested compounds affected estrogen receptor-positive tumor (MCF-7) cell growth, even with different extents, among which, the most active ones proved also to induce mitochondria-mediated apoptosis through activation of PARP cleavage, decrease in Bax/Bcl-2 ratio and increase in Bim gene expression levels. Here we found that the compound 1, carrying a rigid xanthene core, turned out to be the most promising of the set showing an activity profile comparable to that of tamoxifen. Furthermore, a more favorable genotoxic profile than tamoxifen made compound 1 a promising candidate for further studies.

One important strategy to develop effective anticancer agents is based on natural products. Many active phytochemicals are in human clinical trials and have been used for a long time, alone and in association with conventional anticancer drugs, for the treatment of various types of cancers. A great number of in vitro, in vivo and clinical reports document the multi-target anticancer activities of isothiocyanates and of compounds characterized by a naphthalenetetracarboxylic diimide scaffold. In order to search for new anticancer agents with a better pharmaco-toxicological profile, we investigated hybrid compounds obtained by inserting isothiocyanate group(s) on a naphthalenetetracarboxylic diimide scaffold. Moreover, since water-soluble fullerene derivatives can cross cell membranes thus favoring the delivery of anticancer therapeutics, we explored the cytostatic and cytotoxic activity of hybrid compounds conjugated with fullerene. We studied their cytostatic and cytotoxic effects on a human T-lymphoblastoid cell line by using different flow cytometric assays. In order to better understand their pharmaco-toxicological potential, we also analyzed their genotoxicity. Our global results show that the synthesized compounds reduced significantly the viability of leukemia cells. However, the conjugation with a non-toxic vector did not increase their anticancer potential. This opens an interesting research pattern for certain fullerene properties.

It is well documented that damage to DNA could be very harmful for all cells and is the source of several consequences such as cancer development, apoptosis or genetic diseases. In contrast, RNA damage is a poorly examined field in biomedical research, despite its potential to affect cell physiology. For example, a significant loss of RNA integrity has been demonstrated in advanced human atherosclerotic plaques as compared with non-atherosclerotic mammary arteries, and oxidative RNA damage has been described in several neurodegenerative diseases including Alzheimer disease. In the present study, we investigated whether RNA damage could be related to the exposure of particular xenobiotics and then we studied the potential protective activity of creatine against RNA-damaging activity of a series of chemicals with different mechanisms of action [ethyl methanesulfonate (EMS), H(2)O(2), doxorubicin, spermine NONOate, S-nitroso-N-acetylpenicillamine (SNAP)]. Since the protective effect against RNA damage can be mediated by different mechanisms, such as alterations of the rates of toxic agent absorption and uptake, trapping of electrophiles as well as free radicals, and protection of nucleophilic sites in RNA, we used two different treatment protocols (pre- and co-treatment) for understanding the mechanism of the inhibitory activity of creatine. We demonstrated that total RNA is susceptible to chemical attack by doxorubicin, H(2)O(2), spermine and SNAP. Creatine significantly reduced the RNA-damaging activity of only two of the toxic tested agents (H(2)O(2) and doxorubicin), while it lacked activity in counterstaining the RNA damage induced by the NO donors spermine and SNAP. Its inhibitory activity could be at least partially dependent on its capacity to directly scavenge free radicals and/or to maintain phosphocreatine store and ATP regeneration.

Under a Creative Commons license.-- Review.-- et al., Targeted therapies and the consequent adoption of >personalized> oncology have achieved notablesuccesses in some cancers; however, significant problems remain with this approach. Many targetedtherapies are highly toxic, costs are extremely high, and most patients experience relapse after a fewdisease-free months. Relapses arise from genetic heterogeneity in tumors, which harbor therapy-resistantimmortalized cells that have adopted alternate and compensatory pathways (i.e., pathways that are notreliant upon the same mechanisms as those which have been targeted). To address these limitations, aninternational task force of 180 scientists was assembled to explore the concept of a low-toxicity >broad-spectrum> therapeutic approach that could simultaneously target many key pathways and mechanisms. Using cancer hallmark phenotypes and the tumor microenvironment to account for the various aspectsof relevant cancer biology, interdisciplinary teams reviewed each hallmark area and nominated a widerange of high-priority targets (74 in total) that could be modified to improve patient outcomes. For thesetargets, corresponding low-toxicity therapeutic approaches were then suggested, many of which werephytochemicals. Proposed actions on each target and all of the approaches were further reviewed forknown effects on other hallmark areas and the tumor microenvironment. Potential contrary or procar-cinogenic effects were found for 3.9% of the relationships between targets and hallmarks, and mixedevidence of complementary and contrary relationships was found for 7.1%. Approximately 67% of therelationships revealed potentially complementary effects, and the remainder had no known relationship. Among the approaches, 1.1% had contrary, 2.8% had mixed and 62.1% had complementary relationships. These results suggest that a broad-spectrum approach should be feasible from a safety standpoint. Thisnovel approach has potential to be relatively inexpensive, it should help us address stages and types ofcancer that lack conventional treatment, and it may reduce relapse risks. A proposed agenda for futureresearch is offered., Amr Amin was funded by Terry Fox Foundation Grant # TF-13-20 and UAEU Program for Advanced Research (UPAR) #31S118; Jack Arbiser was funded by NIHAR47901; Alexandra Arreola was funded by NIH NRSA Grant F31CA154080; Alla Arzumanyan was funded by NIH (NIAID) R01: Combination therapies for chronic HBV, liver disease, and cancer (AI076535); Work in the lab of Asfar S. Azmi is supported by NIH R21CA188818 as well as from Sky Foundation Inc. Michigan; Fabian Benencia was supported by NIH Grant R15 CA137499-01; Alan Bilsland was supported by the University of Glasgow, Beatson Oncology Centre Fund, CRUK (www.cancerresearchuk.org) Grant C301/A14762; Amancio Carnero was supported by grants from the Spanish Ministry of Economy and Competitivity, ISCIII (Fis: PI12/00137, RTICC: RD12/0036/0028) co-funded by FEDER from Regional Development European Funds (European Union), Consejeria de Ciencia e Innovacion (CTS-6844 and CTS-1848) and Consejeria de Salud of the Junta de Andalucia (PI-0135-2010 and PI-0306-2012). His work on this project has also been made possible thanks to the Grant PIE13/0004 co-funded by the ISCIII and FEDER funds; Stephanie C. Casey was supported by NIH Grant F32CA177139; Mrinmay Chakrabarti was supported by the United Soybean Board; Rupesh Chaturvedi was supported by an NIH NCCAM Grant (K01AT007324); Georgia Zhuo Chen was supported by an NIH NCI Grant (R33 CA161873-02); Helen Chen acknowledges financial support from the Michael Cuccione Childhood Cancer Foundation Graduate Studentship; Sophie Chen acknowledges financial support from the Ovarian and Prostate Cancer Research Trust, UK; Yi Charlie Chen acknowledges financial support from the West Virginia Higher Education Policy Commission/Division of Science Research, his research was also supported by NIH grants (P20RR016477 and P20GM103434) from the National Institutes of Health awarded to the West Virginia IDeA Network of Biomedical Research Excellence; Maria Rosa Ciriolo was partially supported by the Italian Association for Cancer Research (AIRC) Grants #IG10636 and #15403; Helen M. Coley acknowledges financial support from the GRACE Charity, UK and the Breast Cancer Campaign, UK; Marisa Connell was supported by a Michael Cuccione Childhood Cancer Foundation Postdoctoral Fellowship; Sarah Crawford was supported by a research grant from Connecticut State University; Charlotta Dabrosin acknowledges financial support from the Swedish Research Council and the Swedish Research Society; Giovanna Damia gratefully acknowledges the generous contributions of The Italian Association for Cancer Research (IG14536 to G.D.), Santanu Dasgupta gratefully acknowledges the support of the University of Texas Health Science Centre at Tyler, Elsa U. Pardee Foundation; William K. Decker was supported in part by CPRIT, the Cancer Prevention and Research Institute of Texas; Anna Mae E. Diehl was supported by NIH National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), the NIH National Institute on Alcohol Abuse and Alcoholism (NIAAA), Gilead and Shire Pharmaceuticals; Q. Ping Dou was partially supported by NIH/NCI (1R01CA20009, 5R01CA127258-05 and R21CA184788), and NIH P30 CA22453 (to Karmanos Cancer Institute); Janice E. Drew was supported by the Scottish Government's Rural and Environment Science and Analytical Services Division; Eyad Elkord thanks the National Research Foundation, United Arab Emirates University and the Terry Fox Foundation for supporting research projects in his lab; Bassel El-Rayes was supported by Novartis Pharmaceutical, Aveo Pharmaceutical, Roche, Bristol Myers Squibb, Bayer Pharmaceutical, Pfizer, and Kyowa Kirin; Mark A. Feitelson was supported by NIH/NIAID Grant AI076535, Dean W. Felsher was supported by NIH grants (R01CA170378, U54CA149145, and U54CA143907); Lynnette R Ferguson was financially supported by the Auckland Cancer Society and the Cancer Society of New Zealand; Gary L. Firestone was supported by NIH Public Service Grant CA164095 awarded from the National Cancer Institute; Christian Frezza “would like to acknowledge funding from a Medical Research Council CCU-Program Grant on cancer metabolism, and a unique applicant AICR project grant”; Mark M. Fuster was supported by NIH Grant R01-HL107652; Alexandros G. Georgakilas was supported by an EU Marie Curie Reintegration Grant MC-CIG-303514, Greek National funds through the Operational Program ‘Educational and Lifelong Learning of the National Strategic Reference Framework (NSRF)-Research Funding Program THALES (Grant number MIS 379346) and COST Action CM1201 ‘Biomimetic Radical Chemistry’; Michelle F. Green was supported by a Duke University Molecular Cancer Biology T32 Training Grant; Brendan Grue was supported by a National Sciences Engineering and Research Council Undergraduate Student Research Award in Canada; Dorota Halicka was supported by by NIH NCI grant NCI RO1 28704; Petr Heneberg was supported by the Charles University in Prague projects UNCE 204015 and PRVOUK P31/2012, by the Czech Science Foundation projects 15-03834Y and P301/12/1686, by the Czech Health Research Council AZV project 15-32432A, and by the Internal Grant Agency of the Ministry of Health of the Czech Republic project NT13663-3/2012; Matthew D. Hirschey wishes to acknowledge Duke University Institutional Support, the Duke Pepper Older Americans Independence Center (OAIC) Program in Aging Research supported by the National Institute of Aging (P30AG028716-01) and NIH/NCI training grants to Duke University (T32-CA059365-19 and 5T32-CA059365), Lorne J. Hofseth was supported by NIH grants (1R01CA151304, 1R03CA1711326, and 1P01AT003961); Kanya Honoki was supported in part by the grant from the Ministry of Education, Culture, Sports, Science and Technology, Japan (No. 24590493); Hsue-Yin Hsu was supported in part by grants from the Ministry of Health and Welfare (CCMP101-RD-031 and CCMP102-RD-112) and Tzu-Chi University (61040055-10) of Taiwan; Lasse D. Jensen was supported by Svenska Sallskapet for Medicinsk Forskning, Gosta Fraenkels Stiftelse, Ak.e Wibergs Stiftelse, Ollie och Elof Ericssons Stiftelse, Linkopings Universitet and the Karolinska Institute, Sweden; Wen G. Jiang wishes to acknowledge the support by Cancer Research Wales, the Albert Hung Foundation, the Fong Family Foundation, and Welsh Government A4B scheme; Lee W. Jones was supported in part by grants from the NIH NCI; W Nicol Keith was supported by the University of Glasgow, Beatson Oncology Centre Fund, CRUK (www.cancerresearchuk.org) Grant C301/A14762; Sid P. Kerkar was supported by the NIH Intramural Research Program; Rob J. Kulathinal was supported by the National Science Foundation, and the American Cancer Society; Byoung S. Kwon was supported in part by National Cancer Center (NCC-1310430-2) and National Research Foundation (NRF-2005-0093837); Anne Le was supported by Sol Goldman Pancreatic Cancer Research Fund Grant 80028595, a Lustgarten Fund Grant 90049125 and Grant NIHR21CA169757 (to Anne Le); Michael A. Lea was funded by the The Alma Toorock Memorial for Cancer Research; Ho-Young Lee., This work was supported by grants from the National Research Foundation of Korea (NRF), the Ministry of Science, ICT & Future Planning (MSIP), Republic of Korea (Nos. 2011-0017639 and 2011-0030001) and by a NIH Grant R01 CA100816; Liang-Tzung Lin was supported in part by a grant from the Ministry of Education of Taiwan (TMUTOP103005-4); Jason W. Locasale acknowledges support from NIH awards (CA168997 and AI110613) and the International Life Sciences Institute; Bal L. Lokeshwar was supported in part by United States’ Public Health Services Grants: NIH R01CA156776 and VA-BLR&D Merit Review Grant No. 5I01-BX001517-02; Valter D. Longo acknowledges support from NIH awards (P01AG034906 and R01AG020642) and from the V Foundation; Costas A. Lyssiotis was funded in part by the Pancreatic Cancer Action Network as a Pathway to Leadership Fellow and through a Dale F. Frey Breakthrough award from the Damon Runyon Cancer Research Foundation; Karen L. MacKenzie wishes to acknowledge the support from the Children's Cancer Institute Australia (affiliated with the University of New South Wales, Australia and the Sydney Children's Hospital Network); Maria Marino was supported by grant from University Roma Tre to M.M. (CLA 2013) and by the Italian Association for Cancer Research (AIRC-Grant #IG15221), Ander Matheu is funded by Carlos III Health Institute (AM: CP10/00539), Basque Foundation for Science (IKERBASQUE) and Marie Curie CIG Grant (AM: 2012/712404); Christopher Maxwell was supported by funding from the Canadian Institutes of Health Research, in partnership with the Avon Foundation for Women (OBC-134038) and the Canadian Institutes of Health Research New Investigator Salary Award (MSH-136647); Eoin McDonnell received Duke University Institutional Support; Kapil Mehta was supported by Bayer Healthcare System G4T (Grants4Targets); Gregory A. Michelotti received support from NIH NIDDK, NIH NIAAA, and Shire Pharmaceuticals; Vinayak Muralidhar was supported by the Harvard-MIT Health Sciences and Technology Research Assistantship Award; Elena Niccolai was supported by the Italian Ministry of University and the University of Italy; Virginia R. Parslow gratefully acknowledges the financial support of the Auckland Cancer Society Research Centre (ACSRC); Graham Pawelec was supported by the German Federal Ministry of Education and Research (Bundesministerium für Bildung und Forschung, BMBF) Grant number 16SV5536K, and by the European Commission (FP7 259679 “IDEAL”); Peter L. Pedersen was supported by NIH Grant CA-10951; Brad Poore was supported by Sol Goldman Pancreatic Cancer Research Fund Grant 80028595, the Lustgarten Fund Grant 90049125, and Grant NIHR21CA169757 (to Anne Le); Satya Prakash was supported by a Canadian Institutes of Health Research Grant (MOP 64308); Lizzia Raffaghello was supported by an NIH Grant (P01AG034906-01A1) and Cinque per Mille dell’IRPEF–Finanziamento della Ricerca Sanitaria; Jeffrey C. Rathmell was supported by an NIH Grant (R01HL108006); Swapan K. Ray was supported by the United Soybean Board; Domenico Ribatti received funding from the European Union Seventh Framework Programme (FP7/2007–2013) under Grant agreement n°278570; Luigi Ricciardiello was supported by the AIRC Investigator Grants 10216 and 13837, and the European Community's Seventh Framework Program FP7/2007–2013 under Grant agreement 311876; Francis Rodier acknowledges the support of the Canadian Institute for Health Research (FR: MOP114962, MOP125857), Fonds de Recherche Québec Santé (FR: 22624), and the Terry Fox Research Institute (FR: 1030), Gian Luigi Russo contributed to this effort while participating in the Fulbright Research Scholar Program 2013–14; Isidro Sanchez-Garcia is partially supported by FEDER and by MICINN (SAF2012-32810), by NIH Grant (R01 CA109335-04A1), by Junta de Castilla y León (BIO/SA06/13) and by the ARIMMORA project (FP7-ENV-2011, European Union Seventh Framework Program). Isidro Sanchez-Garcia's lab is also a member of the EuroSyStem and the DECIDE Network funded by the European Union under the FP7 program; Andrew J. Sanders wishes to acknowledge the support by Cancer Research Wales, the Albert Hung Foundation, the Fong Family Foundation, and Welsh Government A4B scheme; Neeraj K. Saxena was supported by grant funding from NIH NIDDK (K01DK077137, R03DK089130); Dipali Sharma was partially funded by NIH NCI grants (R01CA131294, R21 CA155686), the Avon Foundation and a Breast Cancer Research Foundation Grant (90047965); Markus David Siegelin received funding from National Institute of Health, NINDS Grant K08NS083732, and the 2013 AACR-National Brain Tumor Society Career Development Award for Translational Brain Tumor Research, Grant Number 13-20-23-SIEG; Neetu Singh was supported by funds from the Department of Science and Technology (SR/FT/LS-063/2008), New Delhi, India; Carl Smythe was supported by Yorkshire Cancer Research and The Wellcome Trust, UK; Carmela Spagnuolo was supported by funding from Project C.I.S.I.A., act n. 191/2009 from the Italian Ministry of Economy and Finance Project CAMPUS-QUARC, within program FESR Campania Region 2007/2013, objectives 2.1, 2.2; Diana M. Stafforini was supported by grants from the National Cancer Institute (5P01CA073992), IDEA Award W81XWH-12-1-0515 from the Department of Defense, and by the Huntsman Cancer Foundation; John Stagg was supported by the Canadian Institutes of Health Research; Pochi R. Subbarayan was supported by the University of Miami Clinical and Translational Science Institute (CTSI) Pilot Research Grant (CTSI-2013-P03) and SEEDS You Choose Awards; Phuoc T. Tran was funded by the DoD (W81XWH-11-1-0272 and W81XWH-13-1-0182), a Kimmel Translational Science Award (SKF-13-021), an ACS Scholar award (122688-RSG-12-196-01-TBG) and the NIH (R01CA166348); Kathryn E. Wellen receives funding from the National Cancer Institute, Pancreatic Cancer Action Network, Pew Charitable Trusts, American Diabetes Association, and Elsa U. Pardee Foundation; Huanjie Yang was partially supported by the Scientific Research Foundation for the Returned Oversea Scholars, State Education Ministry and Scientific and Technological Innovation Project, Harbin (2012RFLXS011), Paul Yaswen was supported by funding from the United States National Institutes of Health (ES019458) and the California Breast Cancer Research Program (17UB-8708); Clement Yedjou was supported by a grant from the National Institutes of Health (Grant # G1200MD007581), through the RCMI-Center for Environmental Health; Xin Yin was supported by NIH/National Heart, Lung, and Blood Institute Training Grant T32HL098062.; Jiyue Zhu was supported by NIH Grant R01GM071725; Massimo Zollo was supported by the European FP7-TuMIC HEALTH-F2-2008-201662, the Italian Association for Cancer research (AIRC) Grant IG # 11963 and the Regione Campania L.R:N.5, the European National Funds PON01-02388/1 2007-2013.

Little is known about the potentially chemopreventive mechanisms of anthocyanins apart from their antioxidant activity. We investigated the in vitro capacity of the anthocyanin cyanidin-3-O-beta-glucopyranoside (Cy-g) to induce apoptosis in T-lymphoblastoid, as well as apoptosis and differentiation in HL-60 promyelocytic cells. Although Cy-g-induced apoptosis (as well as necrosis) in the two systems, HL-60 cells were much less sensitive than T-lymphoblastoid cells. Moreover, treatment of HL-60 cells with Cy-g caused differentiation into macrophage-like cells and granulocytes. Concerning the mechanism of action, the induction of apoptosis in Jurkat T cells can be explained by a modulation of p53 and bax protein expression. At the molecular level, the induction of apoptosis and cytodifferentiation in HL-60 cells involved different proteins, thus suggesting that the effects of Cy-g on apoptosis and cytodifferentiation induction are two distinct events. These interesting biological properties should encourage further investigation into the chemopreventive and/or chemotherapeutic potential of Cy-g.

New polyamine derivatives 1-8, related to the previously reported N(1),N(12)-dibenzyldodecane-1,12-diamine (Bis-Bza-Diado) and N(1)-benzyl-spermine (BD6), have been synthesized and used as "probes" (potential substrates or inhibitors) of the human monoamine oxidases (MAO A and MAO B) and Vascular-Adhesion-protein -1 (VAP-1). Compound 8, the most effective inhibitor of the series, is characterized by a 12-methylene carbon chain ending with an isothiocyanate (ITC) group. Interestingly, it behaves as competitive inhibitor of MAO B and as irreversible inhibitor of MAO A. Compound 3, an asymmetric spermine analogue bearing a thiophene ring, acts as a reversible mixed inhibitor, selective for MAO B (K(IE) = 23 μM). Docking studies performed using the available Protein Data Bank (PDB) structures of MAO A and MAO B, suggested that the different mode of inhibition of 8 may be explained by the different binding poses of 8 into the active site cavities of the two MAO isoforms. The ε-amino group of Lys 305 of MAO A is proposed as possible target of the ITC group of the inhibitor. Further studies are in progress to confirm this hypothesis. These results indicate a potential use of the polyamine scaffold for the development of new MAO inhibitors for application in human pathologies involving these enzymes.

Ethnopharmacological relevance The decoction of the roots of Hemidesmus indicus is widely used in the Indian traditional medicine for the treatment of blood diseases, dyspepsia, loss of taste, dyspnea, cough, poison, menorrhagia, fever, and diarrhea. Poly-herbal preparations containing Hemidesmus are often used by traditional medical practitioners for the treatment of cancer. The aim of this study was to investigate the cytodifferentiative, cytostatic and cytotoxic potential of a decoction of Hemidesmus indicus's roots (0.31–3 mg/mL) on a human promyelocytic leukemia cell line (HL-60). Materials and methods The decoction of Hemidesmus indicus was characterized by HPLC to quantify its main phytomarkers. Induction of apoptosis, cell-cycle analysis, levels of specific membrane differentiation markers were evaluated by flow cytometry. The analysis of cell differentiation by nitroblue tetrazolium (NBT) reducing activity, adherence to the plastic substrate, α-napthyl acetate esterase activity and morphological analysis was performed through light microscopy (LM) and transmission electron microscopy (TEM). Results Starting from the concentration of 0.31 mg/ml, Hemidesmus indicus induced cytotoxicity and altered cell-cycle progression, through a block in the G0/G1 phase. The decoction caused differentiation of HL-60 cells as shown by NBT reducing activity, adherence to the plastic substrate, α-naphtyl acetate esterase activity, and increasing expression of CD14 and CD15. The morphological analysis by LM and TEM clearly showed the presence of granulocytes and macrophages after Hemidesmus indicus treatment. Conclusions The cytodifferentiating, cytotoxic and cytostatic activities of Hemidesmus indicus offers a scientific basis for its use in traditional medicine. Its potent antileukemic activity provides a pre-clinical evidence for its traditional use in anticancer pharmacology. Further experiments are worthwhile to determine the in vivo anticancer potential of this plant decoction and its components.

Anticancer chemotherapy is strongly hampered by the low therapeutic index of most anticancer drugs and the development of chemoresistance. Therefore, there is a continued need for the identification of new molecular targets in order to selectively hit cancer cells. RNA has been recently validated as a cancer target by the use of different specific ligands and/or by different agents able to destroy its diverse forms. The ability of synthetic polyamines to interact and to alter the RNA structure has been already reported. In the present paper the interaction and the ability to damage RNA structure by several synthetic polyamines were evaluated and quantified by microfluid capillary electrophoresis. This technique allowed us to visualize both the RNA impairment through different electropherograms and to assess the RNA integrity number. Finally, the ability to discriminate between RNA and DNA by these synthetic polyamines was also evaluated.

Background The isothiocyanate sulforaphane (SFN) possesses interesting anticancer activities. However, recent studies reported that SFN promotes the formation of reactive oxygen species (ROS) as well as DNA breakage. Methodology/Principal Findings We investigated whether SFN is able to damage RNA, whose loss of integrity was demonstrated in different chronic diseases. Considering the ability of SFN to protect from genotoxicity, we also examined whether SFN is able to protect from RNA damage induced by different chemicals (doxorubicin, spermine, S-nitroso-N-acetylpenicillamine, H2O2). We observed that SFN was devoid of either RNA damaging and RNA protective activity in human leukemic cells. It was able to potentiate the RNA damage by doxorubicin and spermine. In the first case, the effect was attributable to its ability of modulating the bioreductive activation of doxorubicin. For spermine, the effects were mainly due to its modulation of ROS levels produced by spermine metabolism. As to the cytotoxic relevance of the RNA damage, we found that the treatment of cells with a mixture of spermine or doxorubicin plus SFN increased their proapoptotic potential. Thus it is conceivable that the presence of RNA damage might concur to the overall toxic response induced by a chemical agent in targeted cells. Conclusions/Significance Since RNA is emerging as a potential target for anticancer drugs, its ability to enhance spermine- and doxorubicin-induced RNA damage and cytotoxicity could represent an additional mechanism for the potentiating effects of SFN associated with anticancer drugs.

Introduction: Cancer is a complex disease, characterized by redundant aberrant signaling pathways as a result of genetic perturbations at different levels. Botanicals consist of a complex mixture of constituents and exhibit pharmacological effects by the interaction of many phytochemicals. The multitarget nature of botanicals could, therefore, be a relevant strategy to address the biological complexity that characterizes tumors. Areas covered: This article reviews the current status of botanicals in the oncological field and the challenges associated with their complex nature. Expert opinion: Botanicals are an important new pharmacological strategy, which are potentially exploitable in the oncological area but are characterized by a number of problems still unresolved. Content variation of products is one of the primary problems with botanicals and, consequently, there is a concern about the therapeutic consistency in marketed batches. Furthermore, metabolic interactions with antineoplastic drugs and the genotoxic potential of botanicals need to be properly addressed throughout the various phases of botanical drug development. These issues not only pose a serious problem to the approvability of those botanical products as new drugs but also present as a limitation to their post-approval clinical use.

Isothiocyanates, occurring in many dietary cruciferous vegetables, show interesting chemopreventive activities against several chronic–degenerative diseases, including cancer, cardiovascular diseases, neurodegeneration, diabetes. The electrophilic carbon residue in the isothiocyanate moiety reacts with biological nucleophiles and modification of proteins is recognized as a key mechanism underlying the biological activity of isothiocyanates. The nuclear factor-erythroid-2-related factor 2 system, which orchestrates the expression of a wide array of antioxidant genes, plays a role in the protective effect of isothiocyanates against almost all the pathological conditions reported above. Recent emerging findings suggest a further common mechanism. Chronic inflammation plays a central role in many human diseases and isothiocyanates inhibit the activity of many inflammation components, suppress cyclooxygenase 2, and irreversibly inactivate the macrophage migration inhibitory factor. Due to their electrophilic reactivity, some isothiocyanates are able to form adducts with DNA and induce gene mutations and chromosomal aberrations. DNA damage has been demonstrated to be involved in the pathogenesis of various chronic–degenerative diseases of epidemiological relevance. Thus, the genotoxicity of the isothiocyanates should be carefully considered. In addition, the dose–response relationship for genotoxic compounds does not suggest evidence of a threshold. Thus, chemicals that are genotoxic pose a greater potential risk to humans than non-genotoxic compounds. Dietary consumption levels of isothiocyanates appear to be several orders of magnitude lower than the doses used in the genotoxicity studies and thus it is highly unlikely that such toxicities would occur in humans. However, the beneficial properties of isothiocyanates stimulated an increase of dietary supplements and functional foods with highly enriched isothiocyanate concentrations on the market. Whether such concentrations may exert a potential health risk cannot be excluded with certainty and an accurate evaluation of the toxicological profile of isothiocyanates should be prompted before any major increase in their consumption be recommended or their clinical use suggested.

Creatine monohydrate (Cr), the most diffuse supplement in the sports industry, is receiving greater attention because of its beneficial effects in a wide number of human degenerative diseases and conditions. These effects can be barely explained on the basis of the sole ergogenic role of the Cr/CrP system. Indeed, a wide number of research articles indicate that Cr is capable of exerting multiple, non-energy related, effects on diverse and relevant cellular targets. Among these effects, the antioxidant activity of Cr emerges as an additional mechanism which is likely to play a supportive role in the Cr-cytoprotection paradigm.

Depending on the nature of chemical structures, different bile acids exhibit distinct biological effects. Their therapeutic efficacy has been widely demonstrated in various liver diseases, suggesting that they might protect hepatocytes against common mechanisms of liver damage. Although it has been shown to prevent apoptotic cell death in certain cell lines, bile acids significantly inhibited cell growth and induced apoptosis in cancer cells. To better understand the pharmacological potential of bile acids in cancer cells, we investigated and compared the effects of deoxycholic acid (DCA), ursodeoxycholic acid (UDCA), and their taurine-derivatives [taurodeoxycholic acid (TDCA) and tauroursodeoxycholic acid (TUDCA), respectively] on the induction of apoptosis and inhibition of cell proliferation of a human T leukemia cell line (Jurkat cells). All the bile acids tested induced a delay in cell cycle progression. Moreover, DCA markedly increased the fraction of apoptotic cells. The effects of TDCA, UDCA, and TUDCA were different from those observed for DCA. Their primary effect was the induction of necrosis. These distinctive features suggest that the hydrophobic properties of DCA play a role in its cytotoxic potential and indicate that it is possible to create new drugs useful for cancer therapy from bile acid derivatives as lead compounds.

In contrast to damage of genomic DNA and despite its potential to affect cell physiology, RNA damage is a poorly examined field in biomedical research. Potential triggers of RNA damage as well as its pathophysiological implications remain largely unknown. While less lethal than mutations in genome, such non-acutely lethal insults to cells have been recently associated with underlying mechanisms of several human chronic diseases. We investigated whether RNA damage could be related to the exposure of particular xenobiotics by testing the RNA-damaging activity of a series of chemicals with different mechanisms of action. Cultured human T-lymphoblastoid cells were treated with ethyl methanesulfonate (EMS), H(2)O(2), doxorubicin, spermine, or S-nitroso-N-acetylpenicillamine (SNAP). Furthermore, we studied the potential protective activity of a pomegranate extract against RNA damage induced by different chemicals. Special attention has been paid to the protective mechanisms of the extract. The protective effect of pomegranate can be mediated by alterations of the rates of toxic agent absorption and uptake, by trapping of electrophiles as well as free radicals, and protection of nucleophilic sites in RNA. We used two different treatment protocols (pre- and co-treatment) for understanding the mechanism of the inhibitory activity of pomegranate. We demonstrated that total RNA is susceptible to chemical attack. A degradation of total RNA could be accomplished with doxorubicin, H(2)O(2), spermine and SNAP. However, EMS, a well-known DNA-damaging agent, was devoid of RNA-damaging properties, while spermine and SNAP, although lacking of DNA-damaging properties, were able to damage RNA. Pomegranate reduced the RNA-damaging effect of doxorubicin, H(2)O(2), and spermine. Its inhibitory activity could be related with its ability to forms complexes with doxorubicin and H(2)O(2), or interacts with the intracellular formation of reactive species mediating their toxicity. For spermine, an alteration of the rates of spermine absorption and uptake can also be involved.

Carcinogenesis is a multi-step, multi-path and multi-focal process, which involves a series of epigenetic and genetic alterations that begin with genomic instability and end with the development of cancer. This long and complex process presents opportunities for the development of interventions both in preventing cancer initiation and in treating the neoplasm during its premalignant stages. Failure and high systemic toxicity of conventional cancer therapies have accelerated the search for newer agents, which could prevent and/or slow-down cancer growth and have more human acceptability by being less or non-toxic. Now, it is recognized that diets rich in fruits and vegetables are associated with lower risk of cancer. Taking cue from these observations, there is a strong interest in isolating and characterizing the nutritive and non-nutritive components of fruits and vegetables as potential chemopreventive agents. Isothiocyanates and anthocyanins, present in widely consumed fruits and vegetables, are two such agents. In recent years, increasing body of evidence has underscored the cancer preventive efficacy of isothiocyanates and anthocyanins in both in vitro and in vivo animal models. In this review article, we will provide detailed insight into the chemopreventive efficacy of isothiocyanates and anthocyanins based on the evidence generated from various studies performed using cell culture or animal models of epithelial cancers. Moreover, we will discuss the potential clinical relevance of the observed chemopreventive effects of these agents.

Isothiocyanates (ITCs) are sulfur-containing compounds that are broadly distributed among cruciferous vegetables such as cabbages and broccoli. The consumption of ITCs is expected to rise due to the use of dietary supplements and public health initiatives promoting the consumption of more fruits and vegetables. Sulforaphane (SFN) is by far the most widely studied and characterized ITC. SFN is extensively metabolized and can therefore compete with other substrates of Phases I, II, III enzymes and transporters. In addition, it has an unusually high potency as an inducer of phase II enzymes and regulates the expression and function of different cytochrome P-450 genes. Such effects can be beneficial and may indicate a mechanism for the preventive role that SFN is believed to play against the degenerative events of aging and chronic diseases. Furthermore, these gene induction effects and the interaction with detoxification responses can modify bioavailability and in vivo bioactivity of drugs. This review will discuss 1) the metabolism of ITCs using SFN as an example, 2) inhibition of drug metabolism by SFN, and 3) induction of drug metabolizing enzymes by SFN. The potential pharmacological and toxicological implications of these effects on drug metabolism will also be discussed.

Chemoresistance in cancer therapy is a multifactorial process, which includes alterations in drug accumulation, increased activity of gluthatione S-transferases, loss of function, and mutations of p53, etc. One strategy for reversing chemoresistance is the use of chemopreventive agents alongside standard chemotherapeutic protocols. Sulforaphane is one of the most promising chemopreventive agents. Sulforaphane inhibits cell proliferation and induces apoptosis in different tumor cell lines. Its proapoptotic potential could make it effective either alone or in combination with other therapeutic strategies in reversing chemoresistance. We investigated the effects of sulforaphane on mouse fibroblasts bearing a different p53 status (wild-type, knockout, mutated) for understanding whether its activity is prevented by a mutated p53 status. p53-knockout fibroblasts from newborn mice transfected with the p53(Ser220) mutation, observed in different human cancers, were used as a model of mutated p53 status. Moreover, since p53(Ser220) mutation fibroblasts showed a doxorubicin-resistant phenotype, we treated the cells with a combination of doxorubicin plus sulforaphane. Taken together, our results suggest that a mutated p53 status did not prevent the induction of apoptosis by sulforaphane and that sulforaphane was able to reverse the resistance to doxorubicin. The association of sulforaphane-doxorubicin may therefore allow doxorubicin to be administered at lower doses, thereby reducing its potential toxicity.

A number of natural compounds with inhibitory effects on tumorigenesis have been identified from our diet. Several studies have documented the cancer-preventive activity of a significant number of isothiocyanates (ITCs), the majority of which occur in plants, especially in Cruciferous vegetables. The most characterized ITC is sulforaphane (SFN). SFN has received a great deal of attention because of its ability to simultaneously modulate multiple cellular targets involved in cancer development, including: (i) DNA protection by modulating carcinogen-metabolizing enzymes and blocking the action of mutagens; (ii) inhibition of cell proliferation and induction of apoptosis, thereby retarding or eliminating clonal expansion of initiated, transformed, and/or neoplastic cells; (iii) inhibition of neoangiogenesis, progression of benign tumors to malignant tumors, and metastasis formation. SFN is therefore able to prevent, delay, or reverse preneoplastic lesions, as well as to act on cancer cells as a therapeutic agent. Taking into account this evidence and its favorable toxicological profile, SFN can be viewed as a conceptually promising agent in cancer prevention and/or therapy.

Isothiocyanates (ITCs) are commonly found in cruciferous vegetables. A variety of biological activities have been ascribed to ITCs, such as inhibition of cytochrome P450 enzymes and induction of phase II enzymes in animal models. ITCs are also able to block cell-cycle progression and induce apoptosis in human cancer cells in vitro. In this study, we evaluated the ability of the ITC sulforaphane to protect cultured human lymphocytes from micronucleus (MN) induction by four different mutagens: ethyl methanesulfonate (EMS), vincristrine (VIN), H2O2 and mitomycin C (MMC). To understand the mechanisms of action of sulforaphane, the cultures were treated with the compound before, during and after treatment with the mutagens; in addition, the cultures were evaluated for the induction of apoptosis. Up to 10 μM, sulforaphane was non-genotoxic by itself, while 30 μM sulforaphane reduced the replicative index of the cells by more than 60%. Moreover, 1–10 μM sulforaphane reduced the MN frequency induced by EMS, VIN, H2O2 and MMC in at least one of the treatment protocols; it had no effect on H2O2–MN induction in the post-treatment protocol, and it increased MN induction by MMC in the pre-treatment protocol. Apoptosis was produced in the cultures treated with sulforaphane alone. The fraction of apoptotic cells was increased after co- or post-treatment with sulforaphane and EMS and MMC, suggesting that sulforaphane-mediated apoptosis may remove highly damaged cells induced by these agents. Other mechanisms are involved in the anti-genotoxic activity of sulforaphane against VIN and H2O2. Taken together, our findings indicate that under certain conditions sulforaphane possesses anti-genotoxic activity in vitro and that further studies are warranted to characterize this property in vivo. Environ. Mol. Mutagen., 2005. © 2005 Wiley-Liss, Inc.

Cancer chemoprevention is a new approach in the management of cancer. Traditional cytotoxic chemotherapeutic approaches cannot cure most advanced solid malignancies. Chemoprevention can be defined as the use of non-cytotoxic drugs and natural agents to block the progression to invasive cancer. Recently, isothiocyanates, natural products found in the diet of humans, has been shown to function as cancer chemopreventive agents. They are strong inhibitors of phase I enzymes and inducers of phase II enzymes. They can also induce apoptosis and modulate cell-cycle progression of highly proliferating cancer cells. This commentary will review the mechanism of apoptosis and growth inhibition mediated by different isothiocyanates. Particular attention will be given to the effects of the new isothiocyanate 4-(methylthio)butylisothiocyanate (MTBITC). Since selective targeting and low toxicity for normal host tissues are fundamental requisites for proposed chemopreventive agents, we will also review the effects of different isothiocyanates on non-transformed human cells.

We investigated proliferation and apoptosis induction in Jurkat T-leukemia cells by the new isothiocyanate 4-(methylthio)butylisothiocyanate (MTBITC). To help elucidate whether the effects of MTBITC are specific for cancer cells, we tested MTBITC on freshly isolated, non-transformed human peripheral T lymphocytes. The effects of MTBITC are leukemic-cell-specific and consist of derangements in a critical point of cell-cycle control (G2/M transition). In fact, an increase in the proportion of G2 cells (from about 18% to 50%) was apparent following 24 h of treatment, associated with a decrease in the protein expression of cyclin B1. The expression of cyclin-dependent kinase (CDK) 1 was more mildly attenuated by MTBITC. Our results demonstrated that high concentrations of MTBITC can also induce apoptosis, through an increase of p53 and bax, but not bcl-2, protein expression. No effects of MTBITC were demonstrated on non-transformed T lymphocytes. Taking into account its in vitro antineoplastic activity and selectivity toward leukemia cells, MTBITC can be viewed as a conceptually promising agent in cancer therapy.

As with other candidate chemopreventive agents, most of our knowledge on the biological effects of isothiocyanates (the many sulfur-containing metabolites found in cruciferous vegetables) comes from studies of single natural or synthetic compounds. To investigate whether the biological/chemopreventive effects of administration of single isothiocyanates can differ from those of a mixture of isothiocyanates, we tested the effects of a mixture of four different isothiocyanates on cell-cycle progression and apoptosis in human T leukemia Jurkat cells, and identified some of the molecular pathways triggered by the mixture. The mixture affected critical points of the cell cycle via modulation of the expression of cyclin B1. Moreover, it induced apoptosis, mediated by an increase in p53 and bax (expression of bcl-2 was unaffected). Comparison of the data with those previously obtained with the single isothiocyanates under identical experimental conditions provides evidence that the quantitative effects of a single, specific isothiocyanate can be significantly different from those of an isothiocyanate mixture at realistic doses.

Despite growing concern for possible carcinogenic effects associated with environmental benzene exposure in the general population, few studies exist at parts per billion (ppb) levels. We investigated the existence of a relationship between airborne/biological measurements of benzene exposure (i.e., personal/area sampling and unmodified urinary benzene/trans,trans-muconic acid; t,t-MA) and micronuclei induction (cytochalasin B technique) among exposed chemical laboratory workers (n=47) and traffic wardens (n=15). Although urinary t,t-MA (106.9+/-123.17 microg/L(urine)) correlated (R(2)=0.37) with urinary benzene (0.66+/-0.99 microg/L(urine)), neither biological measurement correlated with environmental benzene exposure (14.04+/-9.71 microg/m(3); 4.39+/-3.03ppb), suggesting that, at ppb level (1ppb=3.2 microg/m(3)), airborne benzene constitutes a fraction of the total intake. Traffic wardens and laboratory workers had comparable numbers of micronuclei (4.70+/-2.63 versus 5.76+/-3.11; n.s.), similar to levels recorded in the general population. With univariate/multivariate analysis, no association was found between micronuclei induction and air/urinary benzene exposure variables. Notably, among the personal characteristics examined (including age, gender, smoking, drinking, etc.), high body mass index correlated with micronuclei induction while, among females, use of hormonal medication was associated with less micronuclei. Thus the present study provides no evidence that ppb levels of environmental benzene exposure appreciably affect micronuclei incidence (against the background of other relevant factors). However, this should not be taken as an argument against efforts aiming to reduce environmental benzene pollution.

To investigate whether subjects with low-acid states are exposed to increased genetic risk with respect to controls, we evaluated mutagenicity and presence of clastogenic factors (CF) in the gastric juice of chronic atrophic gastritis and omeprazole-treated patients. Mutagenic gastric juice was found in 8/15 (53%) chronic atrophic gastritis patients, 8/11 (73%) omeprazole-treated patients, and 2/13 (15%) healthy control subjects. The mean mutagenicity ratio of omeprazole-treated patients (1.52 ± 0.48/0.1 ml gastric juice) was significantly higher than those of either controls (1.07 ± 0.15; P < 0.01) or chronic atrophic gastritis patients (1.16 ± 0.21; P < 0.05). Only chronic atrophic gastritis patients showed an increased clastogenic index with respect to healthy controls (2.67 ± 2.13 versus 0.38 ± 0.51; P < 0.001). These findings expand our knowledge of gastric disease risk factors, and indicate that there may well be a risk of mucosal DNA damage arising from the presence of mutagenic and CF in the gastric juice. © 2002 Elsevier Science B.V. All rights reserved.

BackgroundAlthough cancers are characterized by the deregulation of multiple signalling pathways, most current anticancer therapies involve the modulation of a single target. Because of the enormous biological diversity of cancer, strategic combination of agents targeted against the most critical of those alterations is needed. Due to their complex nature, plant products interact with numerous targets and influence several biochemical and molecular cascades. The interest in further development of botanical drugs has been increasing steadily and the FDA recently approved the first new botanical prescription drug. The present study is designed to explore the potential antileukemic properties of Hemidesmus indicus with a view to contributing to further development of botanical drugs. Hemidesmus was submitted to an extensive in vitro preclinical evaluation.Methodology/principal findingsA variety of cellular assays and flow cytometry, as well as a phytochemical screening, were performed on different leukemic cell lines. We have demonstrated that Hemidesmus modulated many components of intracellular signaling pathways involved in cell viability and proliferation and altered the protein expression, eventually leading to tumor cell death, mediated by a loss of mitochondrial transmembrane potential and increased Bax/Bcl-2 ratio. ADP, adenine nucleotide translocator and mitochondrial permeability transition pore inhibitors did not reverse Hemidesmus-induced mitochondrial depolarization. Hemidesmus induced a significant [Ca(2+)](i) raise through the mobilization of intracellular Ca(2+) stores. Moreover, Hemidesmus significantly enhanced the antitumor activity of three commonly used chemotherapeutic drugs (methotrexate, 6-thioguanine, cytarabine). A clinically relevant observation is that its cytotoxic activity was also recorded in primary cells from acute myeloid leukemic patients.Conclusions/significanceThese results indicate the molecular basis of the antileukemic effects of Hemidesmus and identify the mitochondrial pathways and [Ca(2+)](i) as crucial actors in its anticancer activity. On these bases, we conclude that Hemidesmus can represent a valuable tool in the anticancer pharmacology, and should be considered for further investigations.

Sulforaphane is a natural product that is constantly under biological investigation for its unique biological properties. This naturally occurring isothiocyanate (ITC) and its analogs are the main components of cruciferous vegetables, such as cauliflower, watercress, broccoli, cabbage, Brussels sprouts, widely used as chemopreventive agents. Due to their interesting biological profiles, natural ITCs have been exploited as starting point to develop new synthetic analogs. The present mini-review briefly highlights the most important biological actions of selected new synthetic ITCs focusing on their structure-activity relationships and related synthetic strategies.