acetogenins and Neoplasms

Cancer remains a leading cause of death in the USA and around the world. Although the current synthetic inhibitors used in targeted therapies have improved patient prognosis, toxicity and development of resistance to these agents remain a challenge. Plant-derived natural products and their derivatives have historically been used to treat various diseases, including cancer. Several leading chemotherapeutic agents are directly or indirectly based on botanical natural products. Beyond these important drugs, however, a number of crude herbal or botanical preparations have also shown promising utility for cancer and other disorders. One such natural resource is derived from certain plants of the family Annonaceae, which are widely distributed in tropical and subtropical regions. Among the best known of these is Annona muricata, also known as soursop, graviola or guanabana. Extracts from the fruit, bark, seeds, roots and leaves of graviola, along with several other Annonaceous species, have been extensively investigated for anticancer, anti-inflammatory and antioxidant properties. Phytochemical studies have identified the acetogenins, a class of bioactive polyketide-derived constituents, from the extracts of Annonaceous species, and dozens of these compounds are present in different parts of graviola. This review summarizes current literature on the therapeutic potential and molecular mechanism of these constituents from A.muricata against cancer and many non-malignant diseases. Based on available data, there is good evidence that these long-used plants could have both chemopreventive and therapeutic potential. Appropriate attention to safety studies will be important to assess their effectiveness on various diseases caused or promoted by inflammation.

Topics: Acetogenins; Animals; Annona; Antineoplastic Agents, Phytogenic; Humans; Neoplasms; Phytotherapy; Plant Extracts

Plants have provided the basis of traditional medicine systems throughout the world for thousands of years and continue to yield molecules for new remedies. We analyzed studies published from 2009 to 2016 on the Annona species (Annonaceae), including A. coriacea, A. crassifolia, A. hypoglauca, A. muricata, A. squamosa, A. sylvatica, and A. vepretorum, as sources of potential antitumor agents. Here, we report and discuss the mechanisms of action and structure-activity relationships of the most active Annona constituents. Annonaceous acetogenins are one of the most promising classes of natural products, owing to their potential antitumor activity. However, their neurotoxicity should not be underestimated.

Topics: Acetogenins; Annonaceae; Antineoplastic Agents, Phytogenic; Humans; Molecular Structure; Neoplasms; Seeds; Structure-Activity Relationship

Acetogenins (ACG) are naturally occurring compounds that are chemically one of the least investigated families. In the review, we have provided a comprehensive listing of 133 of these compounds for which anti-tumor activity has been documented within the literature. We have compiled and studied their chemical structure, in-vitro as well as in-vivo anticancer biological activity. We observed that the relative potency of acetogenins can be categorized as adjacent bis-THF ACGs > nonadjacent bis-THF ACGs > mono-THF ACGs > linear-THF ACGs. Among adjacent bis-THF ACGs, asiminocin (A100), asiminecin (A101), asiminacin (A102) and asimin (A103) are the most active compounds with in-vitro activity (ED50) in the range of 10(-9) to 10(-12) μg/mL. For the nonadjacent bis-THF ACGs, gigantecin (A53) exhibited better cytotoxicity as compared to others in the series with an ED50 in the range of 10(-6) to 10(-8) μg/mL. Similarly, muricatetrocin-C (A36), a mono-THF and coriadienin (A116) a linear ACG has been reported to show promising cytotoxicity with an ED50 of 10(-5) μg/mL. Moreover, in-vivo studies indicate that compounds like bullatacin (A83), desacetyluvaricin (A76), bullatalicin (A58) and annonacin (A8) have demonstrated significant activity in mouse models and thereby exhibiting potential for lead development as a potential anticancer agent/drug. Also, globally oncologists are looking towards compounds from natural origin that inhibits the growth of resistant tumor cells. We find that several acetogenins like bullatacin (A83), motrilin (A95), asimicin (A77), trilobacin (A96), annonacin (A8), gigantetronenin (A108) and squamocin (A73) are efficacious in suppressing the proliferation of the MDR MCF-7/Adr cells. The present analysis suggests that acetogenins can act as yet another important source for obtaining promising lead compounds in order to contribute to cancer prevention, however, in future extensive in-vivo studies in animal models will be needed to provide insight for lead development.

Topics: Acetogenins; Animals; Antineoplastic Agents, Phytogenic; Cell Proliferation; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Humans; Neoplasms; Structure-Activity Relationship

Chemoprevention is an attempt to use nontoxic natural and synthetic substances or their mixtures to intervene the relatively early stages of carcinogenesis, before invasive characteristics are manifested. The consumption of fruits is well known to reduce the risk of human cancers. Although most fruits are available only on a seasonal basis, recent advances in food processing technologies have made it possible to extend the shelf life of fruits and fruit-products. Fruits can be preserved by applying different drying processes to reduce the moisture content. Different varieties of dried fruits are now sold in supermarkets, thereby making them readily accessible to consumers. Since oxidative stress and chronic inflammation play important roles in cancer development, dried fruits with antioxidative and anti-inflammatory properties hold promise for cancer chemoprevention. The antioxidant, anti-inflammatory and chemopreventive activities of dried fruits are largely attributed to their polyphenols and vitamins. Dried fruits contain adequate amounts of bioactive principles, such as anthocyanins, acetogenins, catechins, coumarins, phenolic acids, terpenes, xanthones, and others. Since numerous health beneficial phytochemicals in fruits are conserved even after processing, regular intake of dried fruits can help prevent cancer. This review addresses the chemopreventive potential of representative dried fruits and their active constituents.

Topics: Acetogenins; Anthocyanins; Anti-Inflammatory Agents; Antioxidants; Catechin; Chemoprevention; Coumarins; Food Handling; Fruit; Humans; Hydroxybenzoates; Inflammation; Neoplasms; Oxidative Stress; Phytochemicals; Terpenes; Xanthones

Annona muricata, also known as graviola, is traditionally used for the treatment of a range of disorders including cancer. Interest in A. muricata use has increased in recent years. This study investigated the quality and safety of a selection of commercially available A. muricata leaf products.. Seven commercially available products were purchased via online shopping sites. Each product was assessed for quality indicators including weight variation, quantification of the bioactive constituent annonacin, presence of annonaceous acetogenins and contaminants. The samples were evaluated by thin-layer chromatography, high-performance liquid chromatography, liquid chromatography-mass spectroscopy, low-resolution mass spectrometry and nuclear magnetic resonance spectroscopy. Microbial analysis was carried out in accordance with the British Pharmacopoeia. Heavy metals were analysed by inductive coupled plasma mass spectrometry.. Of the seven products analysed, one product contained less than half of the content stated on the label. The labelled dosage recommendation varied between products. There was a high variation in annonacin concentration (1.05-3.09 mg/g) and the presence of annonaceous acetogenins. One of the products was found to have a total aerobic microbial count above the United States Pharmacopoeia limit.. The variation in the indicators of quality and safety of commercially available A. muricata leaf products tested have implications for clinicians and people living with cancer who use these herbal products.

Topics: Acetogenins; Annona; Humans; Neoplasms; Plant Extracts; Plant Leaves

Here, we synthesized three acetogenin analogs containing pyrimidine moieties linked by amine bonds, which represent the skeleton structure of pyrimidifen, a mitochondrial complex I-inhibiting insecticide. Replacing the pyrimidine moiety linked by the amine bond remarkably enhanced growth-inhibitory activity of the analogs against several human cancer cell lines. Moreover, these analogs selectively and potently inhibited the growth of these human cancer cell lines regardless of the pyrimidine substituents. Furthermore, COMPARE analyses suggested that these analogs inhibited cancer growth by inhibiting mitochondrial complex I. Our study provides insights into the design of acetogenin analogs as novel antitumor agents.

Topics: Acetogenins; Amines; Antineoplastic Agents; Cell Line, Tumor; Cell Proliferation; Drug Screening Assays, Antitumor; Humans; Molecular Structure; Neoplasms; Pyrimidines; Structure-Activity Relationship

Nineteen biotinylated squamocin/bullatacin derivatives have been synthesized for targeted delivery to biotin receptor overexpressed tumor cells. Most biotinylated squamocin and bullatacin derivatives show similar in vitro cytotoxicity against the biotin receptor non-overexpressed L1210 cells as squamocin and bullatacin, respectively, while against biotin receptor overexpressed 4T1 and P815 tumor cells, several derivatives show significantly higher potency and better selectivity. Among all the synthesized compounds, 15,28-di-O-(6-biotinylamidohexanoyl)squamocin (16) is the most potent, which is 10 and 26 times more active than squamocin against 4T1 and P815 cells, respectively. Compound 16 also appears to be six and fifteen times more selective than squamocin towards 4T1 and P815 cells, respectively, against L1210 cells. The structure activity relationship analysis has revealed that the preferred site for biotinylation is different for squamocin and bullatacin, and it also depends on whether a linking spacer is present.

Topics: Acetogenins; Antineoplastic Agents, Phytogenic; Biotinylation; Cell Line, Tumor; Cell Proliferation; Furans; Humans; Lactones; Neoplasms; Receptors, Growth Factor

Annonaceous acetogenins (ACGs), as one of the most powerful groups of mitochondrial complex I inhibitors, exhibit potent cytotoxic activity against a variety of human tumor cell lines. In this study, the antitumor activities of three main types of ACGs were investigated using S180 and HepS xenografts bearing mice simultaneously. The results revealed that select ACGs suppressed tumor growth in a dose-dependent fashion. Tested ACGs showed more selective antitumor activity against HepS. Furthermore, adjacent bis-THF ACGs were more active than mono-THF and nonadjacent bis-THF ACGs against HepS and S180; nonadjacent bis-THF ACGs were more active than mono-THF ACGs against S180, but mono-THF ACGs were more potent than nonadjacent bis-THF ACGs against HepS.

Topics: Acetogenins; Animals; Antineoplastic Agents; Cell Line, Tumor; Cell Proliferation; Dose-Response Relationship, Drug; Humans; Mice; Molecular Structure; Neoplasms; Transplantation, Heterologous

A new series of linear dimeric compounds mimicking naturally occurring annonaceous acetogenins have been synthesized by bivalent analogue design, and their cytotoxicities have been evaluated against the growth of cancer cells by MTT method. Most of these compounds show selective action favored to human cancer cell lines over normal cell lines, and compound 9 with bis-terminal benzoquinone functionality exhibits an IC(50)=0.40 μM against MCF7 cell lines. This work mentions that appropriate conformational constraints might be a useful optimizing tool for this unique class of anticancer compounds.

Topics: Acetogenins; Antineoplastic Agents; Benzoquinones; Cell Line, Tumor; Cell Proliferation; Cell Survival; Drug Design; Female; Humans; Inhibitory Concentration 50; Molecular Structure; Neoplasms

The convergent synthesis of C35-fluorinated analogues of solamin, a mono-THF Annonaceous acetogenin, has been achieved by the Sonogashira coupling of the THF ring fragment and the fluorinated γ-lactone fragment. It was revealed that the number of fluorine atoms on the γ-lactone moiety affects the growth inhibitory activities against human cancer cell lines.

Topics: Acetogenins; Antineoplastic Agents; Cell Line, Tumor; Cell Proliferation; Drug Design; Drug Screening Assays, Antitumor; Female; Growth Inhibitors; Halogenation; Humans; Male; Neoplasms

Two new annonaceous acetogenins named as squamostanin-C and squamostanin-D were isolated from 95% EtOH extract of the seeds of Annona squamosa. Their structures were determined by spectroscopic method, and their cytotoxicities were evaluated by using MTT method.

Topics: Acetogenins; Annona; Antineoplastic Agents, Phytogenic; Humans; Molecular Structure; Neoplasms; Plant Extracts; Seeds

This report describes the inhibitory activities of the natural and non-natural acetogenins [mucocin (compound 1), jimenezin (compound 2), 19-epi jimenezin (compound 3), muconin (compound 4), pyranicin (compound 5), pyragonicin (compound 6), 10-epi pyragonicin (compound 7), and a gamma-lactone (compound 8)], which were synthesized by us, against DNA polymerase (pol), DNA topoisomerase (topo), and human cancer cell growth. Among the compounds tested, compound 5 was revealed to be the strongest inhibitor of the animal pols and human topos tested, and the IC50 values for pols and topos were 2.3-15.8 and 5.0-7.5 microM, respectively. The compound also suppressed human cancer cell (promyelocytic leukemia cell line, HL-60) growth with the same tendency as the inhibition of pols and topos and the LD50 value was 9.4 microM. Compound 5 arrested the cells at G2/M and G1 phases, and prevented the incorporation of thymidine into the cells, indicating that it blocks DNA replication by inhibiting the activity of pols and topos. This compound also induced apoptosis of the cells. Based on these results, the action mode of compound 5 is discussed.

Topics: Acetogenins; Cell Proliferation; DNA Topoisomerases; DNA-Directed DNA Polymerase; Enzyme Inhibitors; Furans; G1 Phase; G2 Phase; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Neoplastic; HL-60 Cells; Humans; Inhibitory Concentration 50; Lactones; Models, Chemical; Neoplasms; Nucleic Acid Synthesis Inhibitors; Topoisomerase Inhibitors

The antitumoral activity of a series of acetylated bis-tetrahydrofuranic acetogenins with a threo/trans/threo/trans/erythro relative configuration was characterized by four new natural and two semisynthetic, 15,24,30-trioxygenated acetogenins that were found to inhibit mitochondrial complex I enzyme as well as growth of several tumor cell lines. Placement of acetyl groups along the alkyl chain modulated the potency of the bis-tetrahydrofuranic acetogenins and could be important for future utilization of these compounds as chemotherapeutic agents.

Topics: Acetogenins; Antineoplastic Agents; Cell Line, Tumor; Cell Proliferation; Electron Transport Complex I; Fatty Alcohols; Growth Inhibitors; Humans; Lactones; Magnetic Resonance Spectroscopy; Molecular Structure; Neoplasms; Spectrometry, Mass, Electrospray Ionization; Structure-Activity Relationship