Daucosterol inhibits cancer cell proliferation by inducing autophagy through reactive oxygen species-dependent manner

Research Progress on the Anti-Cancer Effects of Astragalus membranaceus Saponins and Their Mechanisms of Action

Astragalus membranaceus saponins are the main components of A. membranaceus, a plant widely used in traditional Chinese medicine. Recently, research on the anti-cancer effects of A. membranaceus saponins has received increasing attention. Numerous in vitro and in vivo experimental data indicate that A. membranaceus saponins exhibit significant anti-cancer effects through multiple mechanisms, especially in inhibiting tumor cell proliferation, migration, invasion, and induction of apoptosis, etc. This review compiles relevant studies on the anti-cancer properties of A. membranaceus saponins from various databases over the past two decades. It introduces the mechanism of action of astragalosides, highlighting their therapeutic benefits in the management of cancer. Finally, the urgent problems in the research process are highlighted to promote A. membranaceus saponins as an effective drug against cancer.

A comprehensive review on traditional uses, phytochemical, and pharmacological properties of the genus Antidesma L

The genus Antidesma L. (Phyllanthaceae) consists of 102 species and is distributed throughout the subtropical, temperate, and subpolar regions. Numerous species in this genus are employed in ethnomedical practices to treat a range of ailments including anaemia, diabetes, herpes, skin infections, typhoid, throat and lung diseases, gastrointestinal, jaundice, rheumatic, and many more diseases. This review aimed to highlight the ethnopharmacological uses, phytochemical components, biological activities, and future research opportunities of the genus. A total number of 112 research papers published between the period 1977 and 2023 were considered and reviewed were retrieved from scientific databases such as Scopus, Web of Science, Elsevier Scient Direct, Google Scholar, and PubMed. The literature study revealed that both plant extracts and phytochemicals exhibited a wide range of biological activities including antidiabetes, anticancer, antimicrobial, anti-inflammation, and many other activities. Overall, a total number of 236 compounds have been encountered from the different species of Antidesma. These compounds belong to different chemical groups such as alkaloids, flavonoids, fatty acids, lignans, sterols, terpenoids, coumarins, and others. Three compounds such as antidesmone, amentoflavone, and β-sitosterol were found to be possible chemotaxonomic markers for the genus Antisema. Furthermore, only 16 species have been investigated in the context of phytochemistry and pharmacological activities of the genus so far. This review could serve as a comprehensive resource for future research in drug discovery and also lay the groundwork for the exploration of additional species within this genus for pharmaceutical applications.

Daucosterol combined with umbilical cord mesenchymal stem cell-derived exosomes can alleviate liver damage in liver failure mice by regulating the IL-6/STAT3 signaling pathway

Daucosterol is a phytosterol glycoside with hepatoprotective properties. The objective of the present study was to confirm the role of daucosterol in liver failure. Exosomes were isolated from primary mouse umbilical cord mesenchymal stem cells (UCMSCs). A liver failure mouse model was generated by injecting lipopolysaccharide/D-galactosamine. Mice were treated with exosomes alone or in combination with daucosterol (5, 10, or 20 mg/kg). Liver tissue damage was examined by hematoxylin-eosin, Masson's trichrome, and TUNEL staining. The levels of genes, proteins, and inflammatory factors were determined using real-time qPCR, western blotting, and enzyme-linked immunosorbent assay, respectively. Compared with normal mice, we noted severe damage, fibrosis, and apoptosis in the liver tissues of liver failure-induced mice. UCMSC-derived exosomes effectively alleviated hepatic damage in the mouse model. Compared with exosome treatment alone, exosomes combined with daucosterol significantly and dose-dependently reduced pathological changes in model mice. Exosome treatment alone or combined with daucosterol also markedly decreased the liver index and reduced levels of alanine aminotransferase, aspartate aminotransferase, tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 in model mice. Exosome treatment alone or combined with daucosterol suppressed mRNA expression levels of IL-6 and signal transducer and activator of transcription (STAT3) and STAT3 protein expression in model mice. Our findings revealed that treatment with daucosterol combined with UCMSC-derived exosomes was superior to exosomes alone for alleviating hepatic damage in mice with liver failure by regulating the IL-6/STAT3 signaling pathway. Accordingly, daucosterol combined with UCMSC-derived exosomes may be a prospective treatment strategy for liver failure.

Exploring the Anti-Osteoporotic Potential of Daucosterol: Impact on Osteoclast and Osteoblast Activities

Osteoporosis is a debilitating condition characterized by reduced bone mass and density, leading to compromised structural integrity of the bones. While conventional treatments, such as bisphosphonates and selective estrogen receptor modulators (SERMs), have been employed to mitigate bone loss, their effectiveness is often compromised by a spectrum of adverse side effects, ranging from gastrointestinal discomfort and musculoskeletal pain to more severe concerns like atypical fractures and hormonal imbalances. Daucosterol (DC), a natural compound derived from various plant sources, has recently garnered considerable attention in the field of pharmacology. In this study, we investigated the anti-osteoporosis potential of DC by characterizing its role in osteoclasts, osteoblasts, and lipopolysaccharide (LPS)-induced osteoporosis. The inhibitory effect of DC on osteoclast differentiation was determined by tartrate-resistant acid phosphatase (TRAP) staining, F-actin ring formation by fluorescent staining, and bone resorption by pit formation assay. In addition, the calcification nodule deposition effect of osteoblasts was determined by Alizarin red S staining. The effective mechanisms of both cells were verified by Western blot and reverse transcription polymerase chain reaction (RT-PCR). To confirm the effect of DC in vivo, DC was administered to a model of osteoporosis by intraperitoneal administration of LPS. The anti-osteoporosis effect was then characterized by micro-CT and serum analysis. The results showed that DC effectively inhibited osteoclast differentiation at an early stage, promoted osteoblast activity, and inhibited LPS-induced bone density loss. The results of this study suggest that DC can treat osteoporosis through osteoclast and osteoblast regulation, and therefore may be considered as a new therapeutic alternative for osteoporosis patients in the future.

Analyze the Effect of Steaming on the Chemical Constituents, Defecation and Liver Injury of Polygonum Multiflorum Radix (Heshouwu) by Multiple Analysis Techniques Combined with Multivariate Statistics

Steaming is a characteristic pharmaceutical skill in Traditional Chinese Medicine (TCM). Polygonum multiflorum radix (PM) and its steamed products have been used in Asia for centuries. Raw Polygonum multiflorum radix (RPM) is commonly used to promote defecation but can exert toxicity, especially in liver injury. However, RPM can be made converted into Polygoni multiflori radix praeparata (PMP) by steaming; this is considered a good method to reduce defecation and liver injury caused by PM in Asia. The chemical constituents of TCM are the key to its action. We systematically analyzed the effect of steaming on PM constituents, defecation, and liver injury. We identified 13 main constituents from PM and PMP; the results showed that after being steamed, two constituents (TSG, catechin) had decreased, six constituents (such as procyanidin B1 or B2) had disappeared, four constituents (such as emodin, physcion) had increased, emodin-8-O-β-D-glucoside remained unchanged in PMP. Pharmacological experiments showed that PM could promote defecation; however, there were no obvious effects in response to PMP. Only a high dose of PM for 14 days caused some degree of liver injury, although this injury disappeared after 14 days of drug withdrawal. Network pharmacology and molecular docking studies showed that TSG, emodin and physcion were the most effective in promoting defecation and causing liver injury. Collectively, our findings show that steaming can reduce the effect of PM on promoting defecation and reducing liver injury. TSG may be one of the important constituents in PM that can promote defecation and cause liver injury.

Smilax china root extract as a novel Glucose- 6-phosphate dehydrogenase inhibitor for the treatment of hepatocellular carcinoma

A novel therapeutic strategy for cancer treatment is to target altered tumor metabolism. Glucose- 6-phosphate dehydrogenase (G6PD) has been recently discovered to be implicated in apoptosis and angiogenesis, making it an excellent target in cancer treatment. The current study aimed to screen the plant extracts library to find potent hits against G6PD through enzymatic assay. Protein expression was induced by IPTG and purified using Ni-NTA columns after transformation of the pET-24a-HmG6PD plasmid into E. coli BL21-DE3 strain. An enzymatic assay was established by using purified rG6PD protein, for the screening of G6PD inhibitors. Out of 46 plant extracts screened, the sixteen plant extracts have shown inhibitory activity against the G6PD enzyme. At doses from 1 to 4 µg/ml, this extract demonstrated concentration-dependent inhibition of G6PD with an IC₅₀ value of I.397 µg/ml. Moreover, the anticancer activity evaluation against HepG2 cells determined Smilax china as a potent inhibitor of cancer cells (IC₅₀ value of 16.017 μg/ml). The acute and subacute toxicities were not observed in mice with various concentrations (50, 100, 200 and 2000 mg/kg). Furthermore, to identify the compounds from Smilax china as G6PD inhibitors, a literature-based phytochemical investigation of Smilax china was conducted, and sixty compounds were docked against the NADP+ and G6P binding sites of G6PD. The results of this study showed that three compounds were Scirpusin A, Smilachinin and Daucosterol with MolDock Score of −156.832, −148.215, and −145.733 respectively, against NADP+ binding site of G6PD. Conclusively, Smilax china root extract could be a safer drug candidate for the treatment of hepatocellular carcinoma.

Natural Sources, Pharmacological Properties, and Health Benefits of Daucosterol: Versatility of Actions

Daucosterol is a saponin present in various natural sources, including medicinal plant families. This secondary metabolite is produced at different contents depending on species, extraction techniques, and plant parts used. Currently, daucosterol has been tested and explored for its various biological activities. The results reveal potential pharmacological properties such as antioxidant, antidiabetic, hypolipidemic, anti-inflammatory, immunomodulatory, neuroprotective, and anticancer. Indeed, daucosterol possesses important anticancer effects in many signaling pathways, such as an increase in pro-apoptotic proteins Bax and Bcl2, a decrease in the Bcl-2/Bax ratio, upregulation of the phosphatase and tensin homolog (PTEN) gene, inhibition of the PI3K/Akt pathway, and distortion of cell-cycle progression and tumor cell evolution. Its neuroprotective effect is via decreased caspase-3 activation in neurons and during simulated reperfusion (OGD/R), increased IGF1 protein expression (decreasing the downregulation of p-AKT3 and p-GSK-3b4), and activation of the AKT5 signaling pathway. At the same time, daucosterol inhibits key glucose metabolism enzymes to keep blood sugar levels within normal ranges. Therefore, this review describes the principal research on the pharmacological activities of daucosterol and the mechanisms of action underlying some of these effects. Moreover, further investigation of pharmacodynamics, pharmacokinetics, and toxicology are suggested.

Ethnobotany, phytochemistry, pharmacology, and conservation of the genus Calanthe R. Br. (Orchidaceae)

ETHNOPHARMACOLOGICAL RELEVANCE

The Genus Calanthe (family Orchidaceae) consists of more than 207 species distributed in both tropical and subtropical regions. In traditional medicine, Calanthe species provide remedies against various conditions such as arthritis, rheumatism, traumatic injuries, snake-bites, abdominal discomfort, nose bleeding, common colds, ulcers, chronic coughs, and others. Some species are also used as aphrodisiacs, tonics, and as pain relievers on joints and toothaches.

AIM OF THE REVIEW

This review provides comprehensive information on the herbal uses, chemical components, pharmacological activities, and conservation of Calanthe, which might be useful in the future development of potent herbal medicines and facilitate the enactment of better conservation strategies.

MATERIALS AND METHODS

Relevant information was obtained from online databases including SCI-Finder, Google Scholar, Web of Science, Science Direct, PubMed, Springer, IOP Science, and other web sources such as PubChem, The Plant List, and World Flora Online. Books, Ph.D. and MSc dissertations were used for unpublished literature. Information from Chinese literature was obtained from the CNKI database.

RESULTS

In total, 19 species of the genus Calanthe have been reported to be used in traditional medicine in different countries of Asia. A total of 265 chemical compounds from different chemical classes including, alkaloids, terpenoids, phenolic compounds and phenolic derivatives, phenanthrenes, and others, have been identified from Calanthe species. Calanquinone A isolated from C. arisanensis has been reported to exhibit antitumor activity against six malignant cell lines. Other bioactive compounds from Calanthe with pharmacological activity include phenanthrenes, phenanthrenequinones, 6'-O-β-D-apiofuranosylindican, 4H-Pyran-4one, 2, 3-dihydro-3,5 dihydroxy-6-methyl, and calanthoside. These compounds exhibit valuable biological properties such as hair restoration, anticancer activity, anti-inflammatory and antiarthritic activity, antidiabetic and hepatoprotective potency, antiplatelet aggregation action, and antibacterial and antifungal activities. Some Calanthe species, including C. ecallosa and C. yuana, are endangered in the IUCN red list. The high risk of extinction is attributed to illegal trade and unsustainable harvesting and utilization.

CONCLUSIONS

This review summarizes the herbal uses, chemical components, biological activity, and conservation of Calanthe. The pharmacological studies on this genus are limited; thus, extensive research on the toxicology, pharmaceutical standardization, and mechanism of action of the isolated bioactive compounds are needed. Since some species of Calanthe are listed as endangered, stringent guidelines on trade, collection, and sustainable utilization of medicinal orchids should be set up to facilitate the conservation of these species.

Exploring the Biological Mechanism of Huang Yam in Treating Tumors and Preventing Antitumor Drug-Induced Cardiotoxicity Using Network Pharmacology and Molecular Docking Technology

Drugs for the treatment of tumors could result in cardiotoxicity and cardiovascular diseases. We aimed to explore the anticancer properties of Huang yam as well as its cardioprotective properties using network pharmacology and molecular docking technology. The cardiovascular targets of the major chemical components of Huang yam were obtained from the following databases: TCMSP, ETCM, and BATMAN-TCM. The active ingredients of Huang yam were obtained from SwissADME. The cardiovascular targets of antitumor drugs were obtained using GeneCards, OMIM, DrugBank, DisGeNET, and SwissTargetPrediction databases. The drug-disease intersection genes were used to construct a drug-compound-target network using Cytoscape 3.7.1. A protein-protein interaction network was constructed using Cytoscape's BisoGenet, and the core targets of Huang yam were screened to determine their antitumor properties and identify the cardiovascular targets based on topological parameters. Potential targets were imported into the Metascape platform for GO and KEGG analysis. The results were saved and visualized using R software. The components with higher median values in the network were molecularly docked with the core targets. The network contained 10 compounds, including daucosterol, delusive, dioxin, panthogenin-B, and 124 targets, such as TP53, RPS27A, and UBC. The GO function enrichment analysis showed that there were 478 items in total. KEGG enrichment analysis showed a total of 140 main pathways associated with abnormal transcription of cancer, PI3K-Akt signaling pathway, cell cycle, cancer pathway, ubiquitination-mediated proteolysis, and other pathways. Molecular docking results showed that daucosterol, delusive, dioxin, and panthogenin-B had the highest affinity for TP53, RPS27A, and UBC. The treatment of diseases using traditional Chinese medicine encompasses multiple active ingredients, targets, and pathways. Huang yam has the potential to treat cardiotoxicity caused by antitumor drugs.

Ethyl Acetate Fraction of Dicliptera chinensis (L.) Juss. Ameliorates Liver Fibrosis by Inducing Autophagy via PI3K/AKT/mTOR/p70S6K Signaling Pathway

OBJECTIVE

To investigate the molecular mechanism underlying the anti-hepatic fibrosis activity of ethyl acetate fraction Dicliptera chinensis (L.) Juss. (EDC) in human hepatic stellate cells (HSCs) in vitro and in a carbon tetrachloride (CCl₄)-induced hepatic fibrosis mouse model in vivo.

METHODS

For in vitro study, HSCs were pre-treated with platelet-derived growth factor (10 ng/mL) for 2 h to ensure activation and treated with EDC for 24 h and 48 h, respectively. The effect of EDC on HSCs was assessed using cell counting kit-8 assay, EdU staining, transmission electron microscopy, immunofluorescence staining, and Western blot, respectively. For in vivo experiments, mice were intraperitoneally injected with CCl₄ (2 ° L/g, adjusted to a 25% concentration in olive oil), 3 times per week for 6 weeks, to develop a hepatic fibrosis model. Forty 8-week-old male C57BL/6 mice were divided into 4 groups using a random number table (n=10), including control, model, positive control and EDC treatment groups. Mice in the EDC and colchicine groups were intragastrically administered EDC (0.5 g/kg) or colchicine (0.2 mg/kg) once per day for 6 weeks. Mice in the control and model groups received an equal volume of saline. Biochemical assays and histological examinations were used to assess liver damage. Protein expression levels of α -smooth muscle actin (α -SMA) and microtubule-associated protein light chain 3B (LC3B) were measured by Western blot.

RESULTS

EDC reduced pathological damage associated with liver fibrosis, downregulated the expression of α -SMA and upregulated the expression of LC3B (P<0.05), both in HSCs and the CCl₄-induced liver fibrosis mouse model. The intervention of bafilomycin A1 and rapamycin in HSCs strongly supported the notion that inhibition of autophagy enhanced α -SMA protein expression levels (P<0.01). The results also found that the levels of phosphoinositide (PI3K), p-PI3K, AKT, p-AKT, mammalian target of rapamycin (mTOR), p-mTOR, and p-p70S6K all decreased after EDC treatment (P<0.05).

CONCLUSIONS

EDC has anti-hepatic fibrosis activity by inducing autophagy and might be a potential drug to be further developed for human liver fibrosis therapy.

Chemical Structure and Biological Activities of Secondary Metabolites from Salicornia europaea L

Salicornia europaea L. is a halophyte that grows in salt marshes and muddy seashores, which is widely used both as traditional medicine and as an edible vegetable. This salt-tolerant plant is a source of diverse secondary metabolites with several therapeutic properties, including antioxidant, antidiabetic, cytotoxic, anti-inflammatory, and anti-obesity effects. Therefore, this review summarizes the chemical structure and biological activities of secondary metabolites isolated from Salicornia europaea L.

Imperata cylindrica: A Review of Phytochemistry, Pharmacology, and Industrial Applications

Imperata cylindrica is a medicinal plant native to southwestern Asia and the tropical and subtropical zones. To date, 72 chemical constituents have been isolated and identified from I. cylindrica Among these compounds, saponins, flavonoids, phenols, and glycosides are the major constituents. Investigations of pharmacological activities of I. cylindrica revealed that this edible medicinal herb exhibits a wide range of therapeutic potential including immunomodulatory, antibacterial, antitumor, anti-inflammatory, and liver protection activities both in vivo and in vitro. The purpose of this review is to provide an overview of I. cylindrica studies until 2019. This article also intends to review advances in the botanical, phytochemical, and pharmacological studies and industrial applications of I. cylindrica, which will provide a useful bibliography for further investigations and applications of I. cylindrica in medicines and foods.

A systems pharmacology approach to identify the autophagy-inducing effects of Traditional Persian medicinal plants

Aging is correlated with several complex diseases, including type 2 diabetes, neurodegeneration diseases, and cancer. Identifying the nature of this correlation and treatment of age-related diseases has been a major subject of both modern and traditional medicine. Traditional Persian Medicine (TPM) embodies many prescriptions for the treatment of ARDs. Given that autophagy plays a critical role in antiaging processes, the present study aimed to examine whether the documented effect of plants used in TPM might be relevant to the induction of autophagy? To this end, the TPM-based medicinal herbs used in the treatment of the ARDs were identified from modern and traditional references. The known phytochemicals of these plants were then examined against literature for evidence of having autophagy inducing effects. As a result, several plants were identified to have multiple active ingredients, which indeed regulate the autophagy or its upstream pathways. In addition, gene set enrichment analysis of the identified targets confirmed the collective contribution of the identified targets in autophagy regulating processes. Also, the protein-protein interaction (PPI) network of the targets was reconstructed. Network centrality analysis of the PPI network identified mTOR as the key network hub. Given the well-documented role of mTOR in inhibiting autophagy, our results hence support the hypothesis that the antiaging mechanism of TPM-based medicines might involve autophagy induction. Chemoinformatics study of the phytochemicals using docking and molecular dynamics simulation identified, among other compounds, the cyclo-trijuglone of Juglans regia L. as a potential ATP-competitive inhibitor of mTOR. Our results hence, provide a basis for the study of TPM-based prescriptions using modern tools in the quest for developing synergistic therapies for ARDs.

Daucosterol from Crateva adansonii DC (Capparaceae) reduces 7,12-dimethylbenz(a)anthracene-induced mammary tumors in Wistar rats

This study aimed to evaluate the in vivo anticancer effects of daucosterol which was earlier reported to possess in vitro anticancer effects. Breast tumor was induced in 30 rats using the environmental carcinogen 7,12-dimethylbenz(a)anthracene (DMBA) while 6 control rats received olive oil (NOR). Animals with palpable tumors were randomized into five groups (n = 6) each as follows: negative control group treated with the vehicle (DMBA); positive control group treated with 5 mg/kg BW doxorubicin (DOXO + DMBA); three groups treated with daucosterol at doses of 2.5, 5, and 10 mg/kg BW (DAU + DMBA). Treatment lasted 28 days afterward, tumor (mass, volume, cancer antigen [CA] 15-3 level and histoarchitecture), hematological and toxicological parameters were examined. The tumor volume gradually increased in the DMBA group during the 28 days, with a tumor volume gain of ∼390 cm³ . Daucosterol at all doses reduced tumor volume (∼133.7 cm³ at 10 mg/kg) as well as protein, malondialdehyde (MDA), and CA 15-3 levels compared to DMBA rats. Tumor sections in daucosterol-treated rats showed a lower proliferation of mammary ducts with mild (5 and 10 mg/kg) to moderate (2.5 mg/kg) inflammatory responses. Moreover, it exhibited an antioxidant effect, evidenced by a significant and dose-dependent decreased in MDA levels, as well as an increase in catalase activity compared to the DMBA group. Daucosterol showed for the first time in vivo antitumor effects that corroborate its previous in vitro effects.

Improvement of cerebral ischemia/reperfusion injury by daucosterol palmitate-induced neuronal apoptosis inhibition via PI3K/Akt/mTOR signaling pathway

Traditional Chinese medicine has growing importance in the treatment of ischemia stroke due to its abundance and low drug resistance. In this study, we aim to investigate the therapeutic potential of daucosterol palmitate against ischemia stroke, as well as its neuro-protective mechanism. The dose-response effects of daucosterol palmitate in the protection from brain damage were evaluated in a cerebral ischemia/reperfusion (I/R) rat model. The correlation of neuro-protective effects of daucosterol palmitate with apoptosis inhibition was examined and the possible signaling targets were identified. Our findings revealed that daucosterol palmitate treatment after 2 h' ischemia significantly lowered brain damage, and neuronal cell apoptosis caused by I/R injury in a dose-response mode (20, 40 and 80 mg/kg). Western blot analysis indicated that daucosterol palmitate could reverse the effects of I/R injury on protein expression of PI3K and mTOR, and phosphorylation of Akt. Contrarily, inactivation of PI3K using wortmannin dramatically antagonized the effect of daucosterol palmitate for I/R injury. With these findings, it supports the application potential of daucosterol palmitate in the treatment of ischemia stroke. Besides, the PI3K/Akt/mTOR pathway might be potential cellular targets for daucosterol palmitate.

Heterogeneous Responses of Gastric Cancer Cell Lines to Tenovin-6 and Synergistic Effect with Chloroquine

Gastric cancer (GC) is the fifth most frequently diagnosed cancer and the third leading cause of cancer death. Approximately 15% of GC is associated with Epstein-Barr virus (EBV). GC is largely incurable with a dismal five-year survival rate. There is an urgent need to identify new therapeutic agents for the treatment of GC. Tenovin-6 was initially identified as a p53 activator, but it was later found to inhibit autophagy flux, and the protein deacetylase activity of sirtuins. Tenovin-6 shows promising therapeutic effect in various malignancies. However, it remains unknown whether Tenovin-6 is effective for GC. In this study, we found that EBV-positive and -negative GC cell lines were sensitive to Tenovin-6 but with different response times and doses. Tenovin-6 suppressed anchorage-independent growth of GC cells. Tenovin-6 induced different levels of apoptosis and phases of cell-cycle arrest depending on the cell lines with some manifesting gap 1 (G1) and others showing synthesis (S) phase cell-cycle arrest. Mechanistically, Tenovin-6 induced autophagy or p53 activation in GC cells depending on the status of TP53 gene. However, initiation of autophagy following treatment with Tenovin-6 conferred some protective effect on numerous cells. Combined treatment with Tenovin-6 and autophagy inhibitor chloroquine increased the cytotoxic effect by inducing microtubule-associated protein 1 light chain 3B (LC3B)-II accumulation, and by enhancing apoptosis and cell-cycle arrest. These results indicated that Tenovin-6 can be used as a potential therapeutic agent for GC, but the genetic background of the cancer cells might determine the response and mechanism of action. Treatment with Tenovin-6 alone or in combination with chloroquine could be a promising therapeutic approach for GC.

A chromosome-scale genome assembly of Isatis indigotica, an important medicinal plant used in traditional Chinese medicine: An Isatis genome

Isatis indigotica (2n = 14) is an important medicinal plant in China. Its dried leaves and roots (called Isatidis Folium and Isatidis Radix, respectively) are broadly used in traditional Chinese medicine for curing diseases caused by bacteria and viruses such as influenza and viral pneumonia. Various classes of compounds isolated from this species have been identified as effective ingredients. Previous studies based on transcriptomes revealed only a few candidate genes for the biosynthesis of these active compounds in this medicinal plant. Here, we report a high-quality chromosome-scale genome assembly of I. indigotica with a total size of 293.88 Mb and scaffold N50 = 36.16 Mb using single-molecule real-time long reads and high-throughput chromosome conformation capture techniques. We annotated 30,323 high-confidence protein-coding genes. Based on homolog searching and functional annotations, we identified many candidate genes involved in the biosynthesis of main active components such as indoles, terpenoids, and phenylpropanoids. In addition, we found that some key enzyme-coding gene families related to the biosynthesis of these components were expanded due to tandem duplications, which likely drove the production of these major active compounds and explained why I. indigotica has excellent antibacterial and antiviral activities. Our results highlighted the importance of genome sequencing in identifying candidate genes for metabolite synthesis in medicinal plants.

Bioguided identification of daucosterol, a compound that contributes to the cytotoxicity effects of Crateva adansonii DC (capparaceae) to prostate cancer cells

ETHNOPHARMACOLOGICAL RELEVANCE

Crateva adansonii DC (Capparaceae) is a shrub used to treat tumors in Cameroon. In our previous reports, a Crateva adansonii dichloromethane-methanol (DCM/MeOH) extract was shown to prevent chemically induced tumors in Wistar rats.

AIM OF STUDY

To determine the bioactive principle of Crateva adansonii extract and to elucidate its underlying mechanism.

MATERIALS AND METHODS

An activity-guided fractionation was realized using MTT assay. To investigate if the bioactive compound daucosterol (CA2) accounted for the previously observed anticancer effects of the C. adansonii extract, it was tested on cell growth, cell proliferation, cell cycle, cell death mechanism and cell migration. In addition, cell cycle- and apoptosis-regulating proteins were assessed by Western blotting.

RESULTS

Daucosterol (CA2), a steroid saponin, was identified as major anticancer principle of the C. adansonii extract. Daucosterol significantly inhibited LNCaP, DU145 and PC3 prostate carcinoma cell growth and proliferation at the optimal concentration of 1 μg/mL. It also significantly increased the number of late apoptotic (DU145) and apoptotic (PC3) cells. The number of cells in S phase increased in DU145, while the number of G0/G1 cells decreased. Cell cycle proteins (cdk1, pcdk1, cyclin A and B) were down-regulated in DU145 and PC3 cells, whereas only cdk2 was down-regulated in PC3 cells. Moreover, the anti-apoptotic Akt, pAKT and Bcl-2 proteins were down-regulated, while the pro-apoptotic protein Bax was up-regulated. CA2 induced anti-metastatic effects by decreasing chemotaxis and cell migration, while it increased cell adhesion to fibronectin and collagen matrix.

CONCLUSION

These results suggest that daucosterol is the major active principle responsible at least in part for the anticancer effect of the extract of Crateva adansonii.

Crystal-Seeded Growth of pH-Responsive Metal-Organic Frameworks for Enhancing Encapsulation, Stability, and Bioactivity of Hydrophobicity Compounds

Zeolitic imidazolate framework-L (ZIF-L) could effectively improve the stability, controlled release, and anticancer activity of natural hydrophobicity drugs in drug delivery systems (DDSs). A simple and universal strategy was developed to prepare the curcumin-loaded ZIF-L (CCM@ZIF-L) by the antisolvent coprecipitation method, which was different from the traditional approaches. The microcrystal molecules of curcumin were used as the core of ZIF-L growth to form CCM@ZIF-L, which has a very high drug encapsulation efficiency of 98.21% and a regular leaf or cruciate flower-like structure. The formation of CCM@ZIF-L with a distinct composite structure was supported by scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared, powder X-ray diffraction, and zeta-potential. Because of the protective effect of ZIF-L, CCM@ZIF-L exhibited excellent stability and about a 5-fold increase in temperature stability over free curcumin. CCM@ZIF-L exhibited controlled drug release behavior in simulated in vitro tumor microenvironments (almost 81.2% drug release over a period of 72 h). Furthermore, confocal laser scanning microscopy results and cytotoxicity experiments confirmed that the encapsulated curcumin showed a significant improvement in cellular uptake and anticancer activity against A549 cancer cells. Moreover, the curcumin encapsulated in ZIF-L exhibited remarkable cellular antioxidant activity based on MGC-803 cell models. This work presents a novel approach to solve the drug loading problem by employing ZIF-L and exhibits enormous potential of ZIF-L as an effective DDS in cancer treatments.

Polyphyllin VI, a saponin from Trillium tschonoskii Maxim. induces apoptotic and autophagic cell death via the ROS triggered mTOR signaling pathway in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) accounts for approximately 85% of all lung cancers. Our previous studies have proven that Trillium tschonoskii Maxim. (TTM), a traditional Chinese medicine, possesses potent anti-tumor effect. However, the detailed components and molecular mechanism of TTM in anti-NSCLC are still unknown. In the present experiment, polyphyllin VI (PPVI) was successfully isolated from TTM with guidance of the anti-proliferative effect in A549 cells, and the cell death of PPVI treated A549 and H1299 cells was closely linked with the increased intracellular ROS levels. In addition, PPVI induced apoptosis by promoting the protein expression of Bax/Bcl2, caspase-3 and caspase-9, and activated autophagy by improving LC3 II conversion and GFP-LC3 puncta formation in A549 and H1299 cells. The mechanism study found that the activity of mTOR which regulates cell growth, proliferation and autophagy was significantly suppressed by PPVI. Accordingly, the PI3K/AKT and MEK/ERK pathways positively regulating mTOR were inhibited, and AMPK negatively regulating mTOR was activated. In addition, the downstream of mTOR, ULK1 at Ser 757 which downregulates autophagy was inhibited by PPVI. The apoptotic cell death induced by PPVI was confirmed, and it was significantly suppressed by the overexpression of AKT, ERK and mTOR, and the induced autophagic cell death which was depended on the Atg7 was decreased by the inhibitors, such as LY294002 (LY), Bafilomycin A1 (Baf), Compound C (CC) and SBI-0206965 (SBI). Furthermore, the mTOR signaling pathway was regulated by the increased ROS as the initial signal in A549 and H1299 cells. Finally, the anti-tumor growth activity of PPVI in vivo was validated in A549 bearing athymic nude mice. Taken together, our data have firstly demonstrated that PPVI is the main component in TTM that exerts the anti-proliferative effect by inducing apoptotic and autophagic cell death in NSCLC via the ROS-triggered mTOR signaling pathway, and PPVI may be a promising candidate for the treatment of NSCLC in future.

Arctium Species Secondary Metabolites Chemodiversity and Bioactivities

Arctium species are known for a variety of pharmacological effects due to their diverse volatile and non-volatile secondary metabolites. Representatives of Arctium species contain non-volatile compounds including lignans, fatty acids, acetylenic compounds, phytosterols, polysaccharides, caffeoylquinic acid derivatives, flavonoids, terpenes/terpenoids and volatile compounds such as hydrocarbons, aldehydes, methoxypyrazines, carboxylic and fatty acids, monoterpenes and sesquiterpenes. Arctium species also possess bioactive properties such as anti-cancer, anti-diabetic, anti-oxidant, hepatoprotective, gastroprotective, antibacterial, antiviral, antimicrobial, anti-allergic, and anti-inflammatory effects. This review aims to provide a complete overview of the chemistry and biological activities of the secondary metabolites found in therapeutically used Arctium species. Summary of pharmacopeias and monographs contents indicating the relevant phytochemicals and therapeutic effects are also discussed, along with possible safety considerations.

Daucosterol induces autophagic-dependent apoptosis in prostate cancer via JNK activation

Plant sterols (phytosterols) have been widely accepted as a natural anti-cancer agent in multiple malignant tumors. This study was designed to investigate the functions of daucosterol in prostate cancer progression and its possible molecular mechanisms. Our results showed that daucosterol inhibited cell proliferation and induced cell cycle arrest. Moreover, daucosterol treatment obviously promoted apoptosis and autophagy. An autophagy inhibitor, 3-methyladenine (3-MA) was proved to counteract daucosterol-triggered autophagy, growth inhibition, and apoptosis, indicating that daucosterol-induced apoptotic response was dependent on autophagy. Additionally, treatment with daucosterol resulted in increased phosphorylation of c-Jun N-terminal kinase (JNK). Furthermore, pre-treatment with a JNK-specific inhibitor SP600125 abated daucosterol-elicited autophagy and apoptotic cell death. Taken together, our findings demonstrated that daucosterol blocked prostate cancer growth at least partly through inducing autophagic-dependent apoptosis via activating JNK signaling, providing a promising candidate for the development of antitumor drugs in prostate cancer treatment.

Extracts from Sageretia thea reduce cell viability through inducing cyclin D1 proteasomal degradation and HO-1 expression in human colorectal cancer cells

Background

Sageretia thea (S. thea) has been used as the medicinal plant for treating hepatitis and fevers in Korea and China. Recently, anticancer activity of S. thea has been reported, but the potential mechanism for the anti-cancer property of S. thea is still insufficient. Thus, we evaluated whether extracts from the leaves (STL) and branches (STB) of S. thea exert anticancer activity and elucidated its potential mechanism in SW480 cells.

Methods

MTT assay was performed for measuring cell viability. Western blot and RT-PCR were used for analyzing the level of protein and mRNA, respectively.

Results

Treatment of STL or STB decreased the cell viability and induced apoptosis in SW480 cells. Decreased level of cyclin D1 protein was observed in SW480 cells treated with STL or STB, but no change in cyclin D1 mRNA level was observed with the treatment of STL or STB. MG132 blocked downregulation of cyclin D1 protein by STL or STB. Thr286 phosphorylation of cyclin D1 by STL or STB occurred faster than downregulation of cyclin D1 protein in SW480 cells. When SW480 cells were transfected with T286A-cyclin D1, cyclin D1 degradation by STL or STB did not occur. Inhibition of GSK3β and cyclin D1 nuclear export attenuated STL or STB-mediated cyclin D1 degradation. In addition, STL or STB increased HO-1 expression, and the inhibition of HO-1 attenuated the induction of apoptosis by STL or STB. HO-1 expression by STL or STB resulted from Nrf2 activation through ROS-dependent p38 activation.

Conclusions

These results indicate that STL or STB may induce GSK3β-dependent cyclin D1 degradation, and increase HO-1 expression through activating Nrf2 via ROS-dependent p38 activation, which resulted in the decrease of the viability in SW480 cells. These findings suggest that STL or STB may have great potential for the development of anti-cancer drug.

Thiophene Derivatives as Anticancer Agents and Their Delivery to Tumor Cells Using Albumin Nanoparticles

A series of thiophene derivatives (TPs) were synthesized and evaluated for cytotoxicity in HepG2 and SMMC-7721 cell lines by MTT assay. TP 5 was identified as a potential anticancer agent based on its ability to inhibit tumor cell growth. Drawbacks of TPs, including poor solubility and high toxicity, were overcome through delivery using self-assembling HSA nanoparticles (NPs). The optimum conditions for TP 5-NPs synthesis obtained by adjusting the temperature and concentration of TP 5. The NPs had an encapsulation efficiency of 99.59% and drug-loading capacity of 3.70%. TP 5 was slowly released from TP 5-NPs in vitro over 120 h. HepG2 and SMMC-7721 cell lines were employed to study cytotoxicity of TP 5-NPs, which exhibited high potency. ROS levels were elevated and mitochondrial membrane potentials reversed when the two cell lines were treated with TP 5-NPs for 12 h. Cellular uptake of fluorescence-labeled TP 5-NPs in vitro was analyzed by flow cytometry and laser confocal scanning microscopy. Fluorescence intensity increased over time, suggesting that TP 5-NPs were efficiently taken up by tumor cells. In conclusion, TP 5-NPs showed great promise as an anticancer therapeutic agent.

Corilagin induces apoptosis, autophagy and ROS generation in gastric cancer cells in vitro

Corilagin, a unique component of the tannin family, has been identified in several medicinal plants. In previous literature, corilagin exhibited a marked anticancer property in a variety of human cancer cells. However, the biological effects of corilagin on gastric cancer and the mechanisms involved remain to be fully elucidated. In the present study, it was reported that corilagin induced inhibition of cell growth in SGC7901 and BGC823 cells in a concentration-dependent manner. It was found that corilagin exhibited less toxicity towards normal GES-1 cells. Furthermore, the study showed that corilagin induced the apoptosis of gastric cancer cells mainly via activating caspase-8, -9, -3 and poly ADP-ribose polymerase proteins. Simultaneously, it was verified that corilagin triggered autophagy in gastric cancer cells and the inhibition of autophagy improved the activity of corilagin on cell growth suppression. In addition, corilagin significantly increased intracellular reactive oxygen species production, which is important in inhibiting the growth of gastric cancer cells. Finally, it was shown that necroptosis cannot be induced by corilagin-incubation in SGC7901 and BGC823 cell lines. Consequently, these findings indicate that corilagin may be developed as a potential therapeutic drug for gastric cancer.

Promotion of Cell Proliferation through Inhibition of Cell Autophagy Signalling Pathway by Rab3IP is Restrained by MicroRNA-532-3p in Gastric Cancer

Background: RAB3A-interacting protein (Rab3IP) is known to be involved in cancer; however, its function during the proliferation of gastric cancer (GC) cells remains unknown. Therefore, this study aimed to explore the potential function of Rab3IP in GC. Methods: The expression of Rab3IP and its clinical pathology value were determined by quantitative real-time PCR and immunohistochemistry. Rab3IP (knockdown and overexpression) and light chain 3 (LC3) lentiviruses were transfected into GC cells, and cell proliferation was measured using cell counting kit-8, plate clone formation, flow cytometry, and tumorigenesis assays. Cell autophagy was measured using a confocal laser scanning microscope and by western blotting. Luciferase reporter assay was performed to analyse the regulation of Rab3IP by microRNA-532-3p (miR-532-3p). Results: Overexpression of Rab3IP in GC samples enhanced the cell proliferation ability, but decreased the number of autophagosomes and expression of LC3-II and sequestosome-1 (SQSTM1 or p62) markers. Furthermore, we found that miR-532-3p can bind to the 3'UTR region of RAB3IP and inhibit the proliferation ability of GC cells. Further, the expression of miR-532-3p negatively correlated with that of Rab3IP. Conclusions: Our study elucidates the central role of Rab3IP in inducing proliferation of GC cells through its involvement in autophagy. miR-532-3p directly targets Rab3IP and represses its function, thereby demonstrating a novel regulatory link in GC.

Anti-breast-Cancer Activity Exerted by β-Sitosterol-d-glucoside from Sweet Potato via Upregulation of MicroRNA-10a and via the PI3K-Akt Signaling Pathway

Breast cancer (BC) is a prominent source of cancer mortality in women throughout the world. β-Sitosterol-d-glucoside (β-SDG), a newly isolated phytosterol from sweet potato, possibly displays potent anticancer activity. However, the probable anticancer mechanisms involved are still unclear. This study sought to study how β-SDG from sweet potato affects two BC cell lines (MCF7 and MDA-MB-231) and nude mice bearing MCF7-induced tumors. In addition, we assessed how β-SDG affects tumor suppressor miR-10a and PI3K-Akt signaling in BC cells. Cell viability and proliferation were determined via MTT and colony-formation assays, and apoptosis was quantified by Hoechst staining and flow cytometry. In addition, miR-10a expression and apoptosis-related protein levels were measured. Our study indicated that β-SDG exhibited cytotoxic activities on MCF7 and MDA-MB-231 cells via inducing apoptosis and activating caspase proteases in these cells. Furthermore, the experimental results in nude mice bearing MCF7-induced tumors demonstrated that oral β-SDG administration at medium (60 mg/kg) or high (120 mg/kg) doses was sufficient to substantially impair the growth of tumors and to decrease the levels of CEA, CA125, and CA153 by 64.71, 74.64, and 85.32%, respectively, relative to those of the controls ( P < 0.01). β-SDG was further found to regulate the expression of PI3K, p-Akt, Bcl-2-family members, and other factors involved in the PI3K-Akt-mediated mitochondrial signaling pathway via the tumor suppressor miR-10a. These findings indicated that β-SDG suppresses tumor growth by upregulating miR-10a expression and inactivating the PI3K-Akt signaling pathway. Furthermore, β-SDG could be developed as a potential therapeutic agent against MCF7-cell-related BC.

Ethnobotany, phytochemistry and pharmacology of Arctotis arctotoides (L.f.) O. Hoffm.: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Arctotis arctotoides (Asteraceae) is part of the genus Arctotis. Arctotis is an African genus of approximately 70 species that occur widely in the African continent with diverse medicinal values. This plant is used for the treatment of indigestion and catarrh of the stomach, epilepsy, topical wounds and skin disorders among the ethnic groups in South Africa and reported to have a wide spectrum of pharmacological properties.

AIM OF THE REVIEW

The aim of the present review is to appraise the botany, traditional uses, phytochemistry, pharmacological potential, analytical methods and safety issues of A. arctotoides. Additionally, this review will help to fill the existing gaps in knowledge and highlight further research prospects in the field of phytochemistry and pharmacology.

MATERIALS AND METHODS

Information on A. arctotoides was collected from various resources, including books on African medicinal herbs and Zulu medicinal plants, theses, reports and the internet databases such as SciFinder, Google Scholar, Pubmed, Scopus, Web of Science, and Mendeley by using a combination of various meaningful keywords. This review surveys the available literature of the species from 1962 to April 2017.

RESULTS

In vitro and in vivo studies of the medicinal properties of A. arctotoides were reviewed. The main isolated and identified compounds were reported as sesquiterpenes, farnesol derivatives, germacranolide, guaianolides and some steroids, of which, nine were reported as antimicrobial. Monoterpenoids and sesquiterpenoids were the predominant essential oil compound classes of the leaves, flowers, stems and roots. The present review revealed potential pharmacological properties such as anti-oxidant, antibacterial, antifungal and anticancer activities of plant extracts as well as isolated compounds. Moreover, the review reports the safety profile (toxicity) of the crude extracts that had been screened on brine shrimps, rats and human cell lines.

CONCLUSIONS

The present review has focused on the phytochemistry, botany, ethnopharmacology, biological activities and toxicological information of A. arctotoides. On the basis of reported data, A. arctotoides has emerged as a good source of natural medicine for the treatment of microbial infections, skin diseases, anti-inflammatory and anticancer agents and also provides new insights for further isolation of new bioactive compounds, especially the discovery of antimicrobial, anti-inflammatory and anticancer novel therapeutic lead drug molecules. Additionally, intensive investigations regarding pharmacological properties, safety assessment and efficacy with their mechanism of action could be future research interests before starting clinical trials for medicinal practices.

Role of Daucosterol Linoleate on Breast Cancer: Studies on Apoptosis and Metastasis

The antitumor property of steroids in sweet potato ( Ipomoea batatas L.) remains poorly understood. Herein, we investigated the anticancer effect on breast carcinoma of daucosterol linoleate (DL), a steroid isolated from sweet potato. DL inhibited the cell viability of estrogen receptor (ER)-positive MCF-7 breast cancer cells at an IC₅₀ value of 53.27 ± 9.02 μg/mL, while the effect was modest in ER-negative MDA-MB-231 breast cancer cells. Flow cytometry indicated that the DL-induced apoptosis in MCF-7 cells is dose-dependent. However, DL inhibited tumor growth and tumor weight at 100 mg/kg in MCF-7 xenograft nude mice. DL diminished the expression of Bcl-xl, Bcl-2, and XIAP, while increasing Bax, Bad, and activated caspase-dependent apoptosis in tumor tissues. Furthermore, DL inactivated the upstream Pi3k/Akt/NF-κB pathway. In the 4T1 spontaneous metastasis model, DL blocked metastasis progression, decreased the number of visible metastasis foci and inhibited metastasis size distribution in lung tissue. Further studies showed that DL suppressed VEGF, MMP 2, and MMP 9 expression in both tumor and lung tissues. From these results, we can assume that DL is a potential adjuvant therapy for ER-positive breast cancer patients.

Transferrin-conjugated liposomes loaded with novel dihydroquinoline derivatives as potential anticancer agents

A series of 1,2-dihydroquinoline derivatives were synthesized and evaluated for cytotoxicity in HeLa, Hep G2 and 6HEK-293T cell lines. EEDQ2 was identified as a promising anti-cancer agent with low IC₅₀ in HeLa (18.55μg/ml) and Hep G2 (14.53μg/ml) cells. For improving the antitumor activity and tumor selectivity of EEDQ2, we prepared transferrin (Tf)-modified liposomes (LPs) to deliver EEDQ2. When HeLa and Hep G2 cells were treated with LP-delivered EEDQ2, the ROS level was significantly enhanced, and mitochondrial membrane potential was reversed. Tf-LPs improved cell uptake of EEDQ2 by about 3.7 times compared with non-targeted LPs. These data suggest that Tf-LPs delivering EEDQ2 is a promising strategy to treat cancer.

Beta sitosterol and Daucosterol (phytosterols identified in Grewia tiliaefolia) perturbs cell cycle and induces apoptotic cell death in A549 cells

Lung cancer is the leading cause of cancer related deaths both in developed and developing countries. Since majority of the existing therapeutic methods harms both normal and malignant cells, a viable alternative is to switch into safe and beneficial traditional medicinal plants. Hence the present study was framed to identify selective anti-lung cancer agents from the medicinal plant Grewia tiliaefolia (GT). Cell viability experiments showed that benzene extract of GT (BGT) leaf effectively inhibited the growth of A549 cells, while being non-toxic to normal human lung L132 and PBMC cells. Ames and comet assays demonstrated that BGT is of non-mutagenic and non-genotoxic nature in untransformed cells. The hematological and histopathological profiles of the in vivo acute and sub-acute toxicity studies demonstrated that BGT is safe and tolerable. Importantly, western blot analysis and Annexin V-FITC staining confirmed that BGT promotes mitochondrial dependent apoptotic cell death in A549 cells by arresting cell cycle at G2/M phase. Bio-assay guided fractionation revealed the presence of phytosteols (β-sitosterol and daucosterol) which significantly inhibited the growth of A549 cells both alone and in combination. This study warrants that these phytosterols in alone or in combination can be considered as safe and potential drug candidates for lung cancer treatment.

Daucosterol Inhibits the Proliferation, Migration, and Invasion of Hepatocellular Carcinoma Cells via Wnt/β-Catenin Signaling

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide. The purpose of this study was to determine the effects of daucosterol on HCC by investigating Wnt/β-catenin signaling. In this study, HepG2 and SMMC-7721 cells were treated with varying concentrations of daucosterol, and the corresponding inhibitory effects on HCC cells were examined via CCK-8 assays. Cell migration and invasion abilities were detected via transwell assays. β-Catenin and phospho (p)-β-catenin levels were analyzed via western blotting. Our results showed that daucosterol reduced the proliferation, migration, and invasion capacities of HCC cells in a concentration-dependent manner. In addition, daucosterol reduced the levels of β-catenin and p-β-catenin in HepG2 and SMMC-7721 cells. Furthermore, the Wnt signaling pathway inhibitor SB-216763 was used to treat HepG2 and SMMC-7721 cells with daucosterol. Our results showed that co-treatment with daucosterol and SB-216763 abolished the effects of daucosterol on cell inhibition ratios, cell migration, and cell invasion. These findings indicated that daucosterol inhibited cell migration and invasion in HCC cells via the Wnt/β-catenin signaling pathway. Therefore, our study highlights the use of daucosterol as a promising therapeutic strategy for HCC treatment.

Negative feedback loop between ZBTB7A and TGF-β in breast cancer

Zinc finger and BTB domain containing 7A (ZBTB7A) is aberrantly expressed in breast cancer, but the involvement of ZBTB7A in breast cancer remains controversial. Transforming growth factor-β (TGF-β) is a pleiotropic cytokine which promotes breast cancer metastasis. ZBTB7A and TGF-β are important factors in tumor development. However, the association between ZBTB7A and TGF-β in breast cancer remains unknown. The results of the present study revealed that TGF-β1 induced the expression of ZBTB7A via the phosphoinositide 3-kinase-protein kinase B signaling pathway in human breast cancer cells, and ZBTB7A inhibited the expression of TGF-β1 through indirectly suppressing the promoter activity of TGF-β1. Furthermore, no significant correlation between the expression of ZBTB7A and TGF-β1 were identified in breast cancer tissues using tissue microarray assay and human cancer genomics analysis. These results have identified a negative feedback loop between ZBTB7A and TGF-β signaling, suggesting ZBTB7A as a potential modulator of breast cancer metastasis. Thus, the results of the present study suggested that ZBTB7A is a potential prognostic biomarker for breast cancer.

Enhanced cytotoxic activity of doxorubicin through the inhibition of autophagy in triple negative breast cancer cell line

BACKGROUND

The outcome of triple negative breast cancer is still poor and requires improvement with better therapy options. Autophagy has recently been shown to play a role in anticancer drug resistance. Therefore, we investigated if the effectiveness of doxorubicin was augmented by the inhibition of autophagy.

METHODS

MDA-MB-231 was used as a model cell line for triple negative breast cancer and 3-methyladenine was used as an inhibitor of autophagy. Cells were treated with 0.46-1.84μM doxorubicin and 2.5-10μM 3-methyladenine for 48h. Cell death mode was examined with M30 and M65 ELISA assays. ROS level and LDH activity was examined and the cellular acidic compartment of cells was monitored by acridine orange staining. The expression of various autophagy and apoptosis related proteins/genes were evaluated with Western blotting and RT-qPCR respectively.

RESULTS

Synergism was observed between the compounds (CI value<1.0). RT-qPCR analysis revealed that the combination resulted in a down-regulation of autophagy-related genes. Moreover, the combination resulted in a different cell death modality, upregulating necroptosis-related genes. This suggests that the mode of cell death may switch from apoptosis to necroptosis, which is a more severe form of cell death, when autophagy is inhibited. These results were further confirmed at protein level by Western blotting.

CONCLUSION

Inhibition of autophagy seems to sensitize triple negative breast cancer cells to doxorubicin, warranting further in vivo studies for the proof of this concept.

GENERAL SIGNIFICANCE

Autophagy has a key role in drug resistance in MDA-MB-231 cells. Therefore combinatorial approaches may effectively overcome resistance.

Induction of MAPK- and ROS-dependent autophagy and apoptosis in gastric carcinoma by combination of romidepsin and bortezomib

Proteasome inhibitors and histone deacetylase (HDAC) inhibitors can synergistically induce apoptotic cell death in certain cancer cell types but their combinatorial effect on the induction of autophagy remains unknown. Here, we investigated the combinatorial effects of a proteasome inhibitor, bortezomib, and an HDAC inhibitor, romidepsin, on the induction of apoptotic and autophagic cell death in gastric carcinoma (GC) cells. Isobologram analysis showed that low nanomolar concentrations of bortezomib/romidepsin could synergistically induce killing of GC cells. The synergistic killing was due to the summative effect of caspase-dependent intrinsic apoptosis and caspase-independent autophagy. The autophagic cell death was dependent on the activation of MAPK family members (ERK1/2 and JNK), and generation of reactive oxygen species (ROS), but was independent of Epstein-Barr virus infection. In vivo, bortezomib/romidepsin also significantly induced apoptosis and autophagy in GC xenografts in nude mice. This is the first report demonstrating the potent effect of combination of HDAC and proteasome inhibitors on the induction of MAPK- and ROS-dependent autophagy in addition to caspase-dependent apoptosis in a cancer type.

Kazakh Ziziphora Species as Sources of Bioactive Substances

Ziziphora species represent the prototypical example of the Lamiaceae family. The phytochemicals present in Ziziphora include monoterpenic essential oils, triterpenes and phenolic substances belonging to the flavonoids. In Kazakh traditional medicine, Ziziphora species possess several medicinal uses. In particular, Z. bungeana Lam. and Z. clinopodioides Lam. are used for the treatment of illnesses related to the cardiovascular system or to combat different infections. Unfortunately, the majority of the information about the complex Ziziphora species is only available in Russian and Chinese language, therefore, we decided gather all available information on Kazakhstan Ziziphora, namely its content compounds, medicinal uses and published patents, to draw the attention of scientists to this very interesting plant with high medicinal potential.

Phytochemistry and pharmacological activities of the genus Prunella

Prunella is a genus of perennial herbaceous plants in the Labiatae family. There are approximately 15 species worldwide, distributed widely in the temperate regions and tropical mountains of Europe and Asia. In the genus Prunella, P. vulgaris is the most studied, following a several thousand-year history as a traditional antipyretic and antidotal Chinese herb. Furthermore, since ancient times, P. vulgaris has been widely used as a cool tea ingredient and consumed as a vegetable. The genus Prunella contains triterpenoids and their saponins, phenolic acids, sterols and associated glycosides, flavonoids, organic acids, volatile oil and saccharides. Modern pharmacological studies have revealed that Prunella possess antiviral, antibacterial, anti-inflammatory, immunoregulatory, anti-oxidative, anti-tumor, antihypertensive and hypoglycemic functions. The active components related to these functions are mainly triterpenoids, phenolic acids, flavonoids and polysaccharides. This review mainly summarizes recent advances in traditional usage, chemical components and pharmacological functions.