Costunolide causes mitotic arrest and enhances radiosensitivity in human hepatocellular carcinoma cells. Radiat Oncol. 2011;6:56. [PMID: 21624128 PMCID: PMC3123574 DOI: 10.1186/1748-717x-6-56]

Exploring the anti-hepatocellular carcinoma effects of Xianglian Pill: Integrating network pharmacology and RNA sequencing via in silico and in vitro studies

BACKGROUND

Liver cancer represents a most common and fatal cancer worldwide. Xianglian Pill (XLP) is an herbal formula holding great promise in clearing heat for treating diseases in an integrative and holistic way. However, due to the complex constituents and multiple targets, the exact molecular mechanisms of action of XLP are still unclear.

PURPOSE

This study is focused on hepatocellular carcinoma (HCC), the most common type of liver cancer. The aim of this study is to develop a fast and efficient model to investigate the anti-HCC effects of XLP, and its underlying mechanisms.

MATERIALS AND METHODS

HepG2, Hep3B, Mahlavu, HuH-7, or Li-7 cells were employed in the studies. The ingredients were analyzed using liquid chromatography tandem mass spectrometry (LC-MS). RNA sequencing combined with network pharmacology was used to elucidate the therapeutic mechanism of XLP in HCC via in silico and in vitro studies. An approach was constructed to improve the accuracy of prediction in network pharmacology by combining big data and omics.

RESULTS

First, we identified 13 potential ingredients in the serum of XLP-administered rats using LC-MS. Then the network pharmacology was performed to predict that XLP demonstrates anti-HCC effects via targeting 94 genes involving in 13 components. Modifying the database thresholds might impact the accuracy of network pharmacology analysis based on RNA sequencing data. For instance, when the matching rate peak is 0.43, the correctness rate peak is 0.85. Moreover, 9 components of XLP and 6 relevant genes have been verified with CCK-8 and RT-qPCR assay, respectively.

CONCLUSION

Based on the crossing studies of RNA sequencing and network pharmacology, XLP was found to improve HCC through multiple targets and pathways. Additionally, the study provides a way to optimize network pharmacology analysis in herbal medicine research.

Progress of natural sesquiterpenoids in the treatment of hepatocellular carcinoma

Hepatocellular carcinoma is one of the common malignant tumors of digestive tract, which seriously threatens the life of patients due to its high incidence rate, strong invasion, metastasis, and prognosis. At present, the main methods for preventing and treating HCC include medication, surgery, and intervention, but patients frequently encounter with specific adverse reactions or side effects. Many Traditional Chinese medicine can improve liver function, reduce liver cancer recurrence and have unique advantages in the treatment of HCC because of their acting mode of multi-target, multi-pathway, multi-component, and multi-level. Sesquiterpenoids, a class of natural products which are widely present in nature and exhibit good anti-tumor activity, and many of them possess good potential for the treatment of HCC. This article reviewed the anti-tumor activities, natural resources, pharmacological mechanism of natural sesquiterpenoids against HCC, providing the theoretical basis for the prevention and treatment of HCC and a comprehensive understanding of their potential for development of new clinical drugs.

Recent advances in lycopene and germacrene a biosynthesis and their role as antineoplastic drugs

Sesquiterpenes and tetraterpenes are classes of plant-derived natural products with antineoplastic effects. While plant extraction of the sesquiterpene, germacrene A, and the tetraterpene, lycopene suffers supply chain deficits and poor yields, chemical synthesis has difficulties in separating stereoisomers. This review highlights cutting-edge developments in producing germacrene A and lycopene from microbial cell factories. We then summarize the antineoplastic properties of β-elemene (a thermal product from germacrene A), sesquiterpene lactones (metabolic products from germacrene A), and lycopene. We also elaborate on strategies to optimize microbial-based germacrene A and lycopene production.

Modulation of mammary tumour progression using murine model by ethanol root extract of Saussurea costus (falc.) lipsch

ETHNOPHARMACOLOGICAL RELEVANCE

Breast cancer is a major cause of death among human females across the globe. The anti-neoplastic agents or therapies used for the treatment of cancers can enhance longevity but are subsequently observed to deteriorate the quality of life due to the extensive side effects produced. Saussurea costus is a potential medicinal plant of the Himalayas with noticeable ethnopharmacological properties. The phytochemicals present in Saussurea costus are responsible for anti-carcinogenic potential and warranted nil or minimal side effects of Saussurea costus and directed to use this plant as a preventive or therapeutic drug candidate against cancers.

AIM OF THE STUDY

The present study was planned to evaluate the anti-neoplastic activity of Saussurea costus root extract (SL) in rat mammary tumour model.

MATERIALS AND METHODS

The anti-neoplastic activity of SL root extract at 3 different doses (100, 250 and 500 mg/kg BW) for 18 weeks against 12-dimethylbenz (a) anthracene (DMBA)-induced mammary tumours in Sprague Dawley (SD) female rats was analyzed through serum biochemistry (ALT, AST, ALP, Total protein, Creatinine and BUN), oxidative stress parameters (Lipid peroxidation, Catalase and Reduced glutathione), pro-inflammatory cytokines (TNF-α and NF-κB), immunohistochemical markers (Ki-67, MMP-9 and VEGF), real-time PCR (PCNA, p53, bax, bcl-2 and caspase-3, genes) and molecular docking.

RESULTS

Inhibition of tumour parameters, minimal alteration in the liver (ALT, AST and ALP) and kidney enzymes (Creatinine and BUN), decreased activity of MDA, elevated levels of GSH and catalase, reduction in the levels of pro-inflammatory cytokines i.e. TNF-α and NF-κB, reduced gross and histomorphological changes, declined expression of Ki-67, MMP-9 and VEGF in vivo rat model, mRNA expression of cancer-related genes and docking of dehydrocostus lactone and costunolide with NF-κB and TNF-α demonstrated the chemopreventive action of SL root extract.

CONCLUSIONS

The in-vivo trial elucidates anti-neoplastic activity of Saussurea costus root extract as demonstrated through the reduction of biochemical indices, oxidative stress parameters, histological changes, pro-inflammatory cytokines (NF-κB and TNF-α), cellular proliferation (Ki-67), metastases (MMP-9) and neovascularization (VEGF) markers with highest anti-neoplastic effect of SL extract at the dose of 500 mg/kg body weight. Therefore, the present study signifies the need to use the active principles present in the root extract of Saussurea costus against breast cancer as a therapeutic regimen.

Naturally Isolated Sesquiterpene Lactone and Hydroxyanthraquinone Induce Apoptosis in Oral Squamous Cell Carcinoma Cell Line

Oral squamous cell carcinoma (OSCC) is one of the most prevalent cancers worldwide, especially in Asian countries. The emergence of its drug resistance and its side effects demands alternatives, to improve prognosis. Since the majority of cancer drugs are derived from natural sources, it provides a window to look for more biocompatible alternatives. In this study, two natural compounds, costunolide (CE) and aloe emodin (AE), were isolated from the stem of Lycium shawii. The compounds were examined for their anticancer and apoptotic potentials against OSCC (CAL 27) cells, using an in vitro analysis, such as a MTT assay, scratch assay, gene, and protein expressions. Both compounds, CE and AE, were found to be cytotoxic against the cancer cells with an IC₅₀ value of 32 and 38 µM, respectively. Moreover, the compounds were found to be non-toxic against normal NIH-3T3 cells and comparable with the standard drug i.e., 5-fluorouracil (IC₅₀ = 97.76 µM). These compounds were active against normal cells at higher concentrations. Nuclear staining displayed the presence of apoptosis-associated morphological changes, i.e., karyopyknosis and karyorrhexis in the treated cancer cells. Flow cytometry results further confirmed that these compounds induce apoptosis rather than necrosis, as the majority of the cells were found in the late apoptotic phase. Gene and protein expression analyses showed an increased expression of apoptotic genes, i.e., BAK, caspase 3, 6, and 9. Moreover, the compounds significantly downregulated the expression of the anti-apoptotic (BCL-2 L1), metastatic (MMP-2), and pro-inflammatory (COX-2) genes. Both compounds have shown promising anticancer, apoptotic, and anti-migratory activities against the OSCC cell line (i.e., CAL-27). However, further in vivo studies are required to explore these compounds as anticancer agents.

Optimization of Supercritical Carbon Dioxide Extraction of Saussurea costus Oil and Its Antimicrobial, Antioxidant, and Anticancer Activities

Saussurea costus is a medicinal plant with different bioactive compounds that have an essential role in biomedicine applications, especially in Arab nations. However, traditional extraction methods for oils can lead to the loss of some volatile and non-volatile oils. Therefore, this study aimed to optimize the supercritical fluid extraction (SFE) of oils from S. costus at pressures (10, 20, and 48 MPa). The results were investigated by GC/MS analysis. MTT, DPPH, and agar diffusion methods assessed the extracted oils’ anticancer, antioxidant, and antimicrobial action. GC/MS results showed that elevated pressure from 10 to 20 and 48 MPa led to the loss of some valuable compounds. In addition, the best IC₅₀ values were recorded at 10 MPa on HCT, MCF-7, and HepG-2 cells at about 0.44, 0.46, and 0.74 μg/mL, respectively. In contrast, at 20 MPa, the IC₅₀ values were about 2.33, 6.59, and 19.0 μg/mL, respectively, on HCT, MCF-7, and HepG-2 cells, followed by 48 MPa, about 36.02, 59.5, and 96.9 μg/mL. The oil extract at a pressure of 10 MPa contained much more of á-elemene, dihydro-à-ionone, patchoulene, á-maaliene, à-selinene, (-)-spathulenol, cedran-diol, 8S,13, elemol, eremanthin, á-guaiene, eudesmol, ç-gurjunenepoxide-(2), iso-velleral, and propanedioic acid and had a higher antioxidant activity (IC₅₀ 14.4 μg/mL) more than the oil extract at 20 and 48 MPa. In addition, the inhibitory activity of all extracts was higher than gentamicin against all tested bacteria. One of the more significant findings from this study is low pressure in SFE enhancement, the extraction of oils from S. costus, for the first time. As a result, the SFE is regarded as a good extraction technique since it is both quick and ecologically friendly. Furthermore, SFE at 10 MPa increased the production and quality of oils, with high antioxidant activity and a positive effect on cancer cells and pathogens.

Network pharmacology and experimental verification based research into the effect and mechanism of Aucklandiae Radix-Amomi Fructus against gastric cancer

To investigate the mechanism of the Aucklandiae Radix–Amomi Fructus (AR–AF) herb pair in treating gastric cancer (GC) by using network pharmacology and experimental verification. Using the traditional Chinese medicine system pharmacology database and analysis platform (TCMSP), the major active components and their corresponding targets were estimated and screened out. Using Cytoscape 3.7.2 software, a visual network was established using the active components of AR–AF and the targets of GC. Based on STRING online database, the protein interaction network of vital targets was built and analyzed. With the Database for Annotation, Visualization, and Integrated Discovery (DAVID) server, the gene ontology (GO) biological processes and the Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathways of the target enrichment were performed. AutoDock Vina was used to perform molecular docking and calculate the binding affinity. The mRNA and protein expression levels of the hub targets were analyzed by the Oncomine, GEPIA, HPA databases and TIMER online tool, and the predicted targets were verified by qRT–PCR in vitro. Eremanthin, cynaropicrin, and aceteugenol were identified as vital active compounds, and AKT1, MAPK3, IL6, MAPK1, as well as EGFR were considered as the major targets. These targets exerted therapeutic effects on GC by regulating the cAMP signaling pathway, and PI3K-Akt signaling pathway. Molecular docking revealed that these active compounds and targets showed good binding interactions. The validation in different databases showed that most of the results were consistent with this paper. The experimental results confirmed that eremanthin could inhibit the proliferation of AGS by reducing the mRNA expression of hub targets. As predicted by network pharmacology and validated by the experimental results, AR–AF exerts antitumor effects through multiple components, targets, and pathways, thereby providing novel ideas and clues for the development of preparations and the treatment of GC.

Anticancer mechanism of 7-α-hydroxyfrullanolide on microtubules and computational prediction of its target binding in triple-negative breast cancer cells

Background

Triple-negative breast cancer (TNBC) responds poorly to the available drugs; thus, the mortality rate associated with TNBC remains high. 7-α-Hydroxyfrullanolide (7HF) possesses anticancer properties and arrests cells in the G2/M-phase via modulation of several proteins involved in the G2/M-phase transition, as well as the mitotic checkpoint in MDA-MB-468 (TNBC) cells. Microtubules (MTs) dynamically regulate cell division in the G2/M phase and are related to cancer cell stress response. However, antimitotic drug cytotoxicity to multiple cancer resistance developed in response to drugs are obstacles faced to date. Here, the activity and mechanism via which 7HF controls MTs dynamics was investigated in MDA-MB-468 cells.

Methods

7HF uptake by MDA-MB-468 cells was assessed using spectrophotometry. The drug-like properties of 7HF were predicted using the Swiss-absorption, distribution, metabolism, and excretion (ADME) webtool. Then, the effect of 7HF treatment (6, 12, and 24 µM) on the dynamic arrangement of MTs was assessed for 1, 12, and 24 h using indirect immunofluorescence. Polymerization of α- and β-tubulin was assessed using different 7HF concentrations in a cell-free system for 1 h. Cell proliferation assay with bromodeoxyuridine plus propidium iodide staining and flow cytometry was performed at different 7HF concentrations and time points. The mechanism of action was assessed by detecting the expression of proteins, including Bub3, cyclin B1, p-Cdk1 (Tyr15), Rb, p-Rb (Ser780), Chk1, p-Chk1 (Ser345), Chk2, p-Chk2 (Ser516), and p-H2AX (Ser139), using western blotting. Molecular docking was used to predict the molecular interactions between 7HF and tubulins in MTs.

Results

We observed that 7HF was able to enter the MDA-MB-468 cells. The ADME webtool analysis predicted that it possesses the high passive permeation and gastrointestinal absorption properties of drugs. Various concentrations of 7HF disrupted the dynamic arrangement of spindle MTs by causing radial spindle array shrinkage and expansion of fibrous spindle density and radial array lengths in a time-dependent manner. 7HF reduced polymerization of α-, β-tubulin in dose-dependent manner. 7HF also triggered DNA damage response by inducing G2/M and G1 phase arrests in a concentration and time-dependent manner, which occurred due to the upregulation of Bub3, Chk1, p-Chk1 (Ser345), p-Cdk1 (Tyr15), and cyclin B1. According to molecular docking analysis, 7HF preferred to bind to β-tubulin over α-tubulin. The lactone, ketone, and hydroxyl groups of 7HF supported the 7HF-tubulin interactions. Hydrogen bonding with a hydrocarbon ring and salt bridge attractive forces were responsible for the binding versatility of 7HF.

Conclusions

This is the first study to investigate the molecular mechanism, MTs interacting sites, and the internalization and drug-like properties of 7HF in TNBC cells. The findings will be useful for developing 7HF-based treatment for patients with TNBC.

Anticancer Effects and Molecular Action of 7-α-Hydroxyfrullanolide in G2/M-Phase Arrest and Apoptosis in Triple Negative Breast Cancer Cells

Triple negative breast cancer (TNBC) is a breast cancer subtype characterized by the absence of estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 expression. TNBC cells respond poorly to targeted chemotherapies currently in use and the mortality rate of TNBC remains high. Therefore, it is necessary to identify new chemotherapeutic agents for TNBC. In this study, the anti-cancer effects of 7-α-hydroxyfrullanolide (7HF), derived from Grangea maderaspatana, on MCF-7, MDA-MB-231 and MDA-MB-468 breast cancer cells were assessed using MTT assay. The mode of action of 7HF in TNBC cells treated with 6, 12 and 24 µM of 7HF was determined by flow cytometry and propidium iodide (PI) staining for cell cycle analysis and annexin V/fluorescein isothiocyanate + PI staining for detecting apoptosis. The molecular mechanism of action of 7HF in TNBC cells was investigated by evaluating protein expression using proteomic techniques and western blotting. Subsequently, 7HF exhibited the strongest anti-TNBC activity toward MDA-MB-468 cells and a concomitantly weak toxicity toward normal breast cells. The molecular mechanism of action of low-dose 7HF in TNBC cells primarily involved G2/M-phase arrest through upregulation of the expression of Bub3, cyclin B1, phosphorylated Cdk1 (Tyr 15) and p53-independent p21. Contrastingly, the upregulation of PP2A-A subunit expression may have modulated the suppression of various cell survival proteins such as p-Akt (Ser 473), FoxO3a and β-catenin. The concurrent apoptotic effect of 7HF on the treated cells was mediated via both intrinsic and extrinsic modes through the upregulation of Bax and active cleaved caspase-7-9 expression and downregulation of Bcl-2 and full-length caspase-7-9 expression. Notably, the proteomic approach revealed the upregulation of the expression of pivotal protein clusters associated with G1/S-phase arrest, G2/M-phase transition and apoptosis. Thus, 7HF exhibits promising anti-TNBC activity and at a low dose, it modulates signal transduction associated with G2/M-phase arrest and apoptosis.

Nanonutraceuticals: Anti-Cancer Activity and Improved Safety of Chemotherapy by Costunolide and Its Nanoformulation against Colon and Breast Cancer

Costunolide (COS) is a sesquiterpene lactone with anticancer properties. The present study investigated the anticancer effects of COS against the human colon (HCT116) and breast (MDA-MB-231-Luc) cancer cell lines. Inhibition of cell lines viability and IC50 of COS were assessed via an MTT assay. Furthermore, the apoptotic rate was detected by assessment of Bcl2-associated X (Bax) and B-cell lymphoma 2 (Bcl2) protein levels by flow cytometry. Xenograft mice model of HCT116 and MDA-MB-231-Luc were carried out to determine the effect of COS and its nanoparticles (COS-NPs). The results demonstrated that COS inhibited the viability of HCT116 and MDA-MB-231-Luc cells, with a half maximal inhibitory concentration value (IC50) of 39.92 µM and 100.57 µM, respectively. COS significantly increased Bax and decreased Bcl2 levels in treated cells. COS and COS-NPs, in combination with doxorubicin (DOX), significantly decreased the tumor growth of HCT116 and MDA-MB-231-Luc implants in mice. Furthermore, oral administration of COS and COS-NPs significantly decreased the viable cells and increased necrotic/apoptotic cells of HCT116 and MDA-MB-231-Luc implants. Interestingly, both COS and COS-NPs protected the cardiac muscles against DOX’s cardiotoxicity. The current results indicated the promising anticancer and cardiac muscles protection of COS and COS-NPs when administered with chemotherapy.

Costunolide Induces Apoptosis via the Reactive Oxygen Species and Protein Kinase B Pathway in Oral Cancer Cells

Oral cancer (OC) has been attracted research attention in recent years as result of its high morbidity and mortality. Costunolide (CTD) possesses potential anticancer and bioactive abilities that have been confirmed in several types of cancers. However, its effects on oral cancer remain unclear. This study investigated the potential anticancer ability and underlying mechanisms of CTD in OC in vivo and in vitro. Cell viability and anchorage-independent colony formation assays were performed to examine the antigrowth effects of CTD on OC cells; assessments for migration and invasion of OC cells were conducted by transwell; Cell cycle and apoptosis were investigated by flow cytometry and verified by immunoblotting. The results revealed that CTD suppressed the proliferation, migration and invasion of oral cancer cells effectively and induced cell cycle arrest and apoptosis; regarding the mechanism, CTD bound to AKT directly by binding assay and repressed AKT activities through kinase assay, which thereby downregulating the downstream of AKT. Furthermore, CTD remarkably promotes the generation of reactive oxygen species by flow cytometry assay, leading to cell apoptosis. Notably, CTD strongly suppresses cell-derived xenograft OC tumor growth in an in vivo mouse model. In conclusion, our results suggested that costunolide might prevent progression of OC and promise to be a novel AKT inhibitor.

Costunolide, a Sesquiterpene Lactone, Suppresses Skin Cancer via Induction of Apoptosis and Blockage of Cell Proliferation

Costunolide is a naturally occurring sesquiterpene lactone that demonstrates various therapeutic actions such as anti-oxidative, anti-inflammatory, and anti-cancer properties. Costunolide has recently emerged as a potential anti-cancer agent in various types of cancer, including colon, lung, and breast cancer. However, its mode of action in skin cancer remains unclear. To determine the anti-cancer potential of costunolide in skin cancer, human epidermoid carcinoma cell line A431 was treated with costunolide. A lactate dehydrogenase assay showed that costunolide diminished the viability of A431 cells. Apoptotic cells were detected by annexin V/propidium iodide double staining and Terminal deoxynucleotidyl transferase mediated dUTP nick end labeling assay assay, and costunolide induced cell apoptosis via activation of caspase-3 as well as induction of poly-ADP ribose polymerase cleavage in A431 cells. In addition, costunolide elevated the level of the pro-apoptotic protein Bax while lowering the levels of anti-apoptotic proteins, including Bcl-2 and Bcl-xL. To address the inhibitory effect of costunolide on cell proliferation and survival, various signaling pathways, including mitogen-activated protein kinases, signal transducer and activator of transcription 3 (STAT3), nuclear factor κB (NF-κB), and Akt, were investigated. Costunolide activated the p38 and c-Jun N-terminal kinase pathways while suppressing the extracellular signal-regulated kinase (ERK), STAT3, NF-κB, and Akt pathways in A431 cells. Consequently, it was inferred that costunolide suppresses cell proliferation and survival via these signaling pathways. Taken together, our data clearly indicated that costunolide exerts anti-cancer activity in A431 cells by suppressing cell growth via inhibition of proliferation and promotion of apoptosis. Therefore, it may be employed as a potentially tumor-specific candidate in skin cancer treatment.

Natural and Synthetic Lactones Possessing Antitumor Activities

Cancer is one of the leading causes of death globally, accounting for an estimated 8 million deaths each year. As a result, there have been urgent unmet medical needs to discover novel oncology drugs. Natural and synthetic lactones have a broad spectrum of biological uses including anti-tumor, anti-helminthic, anti-microbial, and anti-inflammatory activities. Particularly, several natural and synthetic lactones have emerged as anti-cancer agents over the past decades. In this review, we address natural and synthetic lactones focusing on their anti-tumor activities and synthetic routes. Moreover, we aim to highlight our journey towards chemical modification and biological evaluation of a resorcylic acid lactone, L-783277 (4). We anticipate that utilization of the natural and synthetic lactones as novel scaffolds would benefit the process of oncology drug discovery campaigns based on natural products.

Quality assessment of raw and baked Aucklandia lappa Decne. by color measurement and fingerprint analysis

Aucklandia lappa Decne. has been used as a traditional Chinese herb for thousands of years in treating various kinds of disorders. According to the Chinese Pharmacopoeia, there are two kinds of processed products, raw and baked Aucklandia lappa Decne., which have different therapeutic effect in clinical application. In this study, based on color measurement and fingerprint analysis, the method to assess the quality of these two processed products was established. In color measurement, the reference ranges of color parameters (L^* , a^* , and b^* ), standard color difference values, and mathematical prediction functions of these two processed products were obtain after the color was measured by a spectrophotometer. Meanwhile, high-performance liquid chromatography fingerprints of these two processed products were established, where there were 12 peaks recognized as the common peaks in both processed products, in which two peaks were identified as costunolide and dehydrocostus lactone, and these two processed products were classified with chemometrics analysis subsequently. Furthermore, the correlation between color parameters and sample compositions was explored and the contents of costunolide and dehydrocostus lactone were determined simultaneously by high-performance liquid chromatography. Consequently, an integral method including color measurement, high-performance liquid chromatography fingerprint with chemometrics analysis, and quantitative determination was established.

Costunolide Plays an Anti-Neuroinflammation Role in Lipopolysaccharide-Induced BV2 Microglial Activation by Targeting Cyclin-Dependent Kinase 2

Hyperactivation of microglia in the brain is closely related to neuroinflammation and leads to neuronal dysfunction. Costunolide (CTL) is a natural sesquiterpene lactone with wide pharmacological activities including anti-inflammation and antioxidation. In this study, we found that CTL significantly inhibited the production of inflammatory mediators including nitric oxide, IL-6, TNF-α, and PGE2 in lipopolysaccharide (LPS)-stimulated BV2 microglia. Moreover, CTL effectively attenuated IKKβ/NF-κB signaling pathway activation. To identify direct cellular target of CTL, we performed high-throughput reverse virtual screening assay using scPDB protein structure library, and found cyclin-dependent kinase 2 (CDK2) was the most specific binding protein for CTL. We further confirmed the binding ability of CTL with CDK2 using cellular thermal shift assay (CETSA) and drug affinity responsive target stability (DARTS) assays. Surface plasmon resonance analysis also supported that CTL specifically bound to CDK2 with a dissociation constant at micromole level. Furthermore, knocking down CDK2 obviously reversed the anti-inflammation effect of CTL via AKT/IKKβ/NF-κB signaling pathway on BV-2 cells. Collectively, these results indicate that CTL inhibits microglia-mediated neuroinflammation through directly targeting CDK2, and provide insights into the role of CDK2 as a promising anti-neuroinflammation therapeutic target.

Antitumor activity and mechanism of costunolide and dehydrocostus lactone: Two natural sesquiterpene lactones from the Asteraceae family

Costunolide (COS) and dehydrocostus lactone (DEH) are two natural sesquiterpene lactones with potential antitcancer activity against a range of cancer cell types both in vitro and in vivo, particularly for breast cancer and leukemia. There are many researches that have been taken to characterize these pathways and to reveal their anticancer mechanisms of action of COS and DEH. However, while there is a great deal of evidence detailing the effects of COS and DEH on considerable signaling pathways and cellular functions, a global view of their mechanism of action remains elusive. This review systematically summarizes the antitumor activity and mechanism of COS and DEH in the recent reports, and discusses the effect of the key active part (α-methylene-γ-butyrolactone) of COS and DEH against cancer. Moreover, we also discuss the antineoplastic activity of COS and DEH derivatives to improve the cytotoxicity and safety index. We believe this review can provide a systemic reference to develop COS and DEH as anticancer agents.

Bioactive components of ethnomedicine Eerdun Wurile regulate the transcription of pro-inflammatory cytokines in microglia

ETHNOPHARMACOLOGICAL RELEVANCE

The traditional Mongolian medicine Eerdun Wurile (EW) has remarkable neural recovery effect, and has been playing a key role in the clinical treatment of neurological disorders including ischemic stroke in Inner Mongolia Autonomous Region of China. The preliminary pharmacological studies in animal suggested that EW regulates the expression of trophic factors in brain lesion and may also balance the polarization of activated microglia (Gaowa et al., 2018).

AIM OF THE STUDY

The pool of leading bioactive chemicals underlying the therapeutic effects of EW has not been identified. Therefore, the mechanism of action of EW is poorly understood. This study was aimed to identify the major group of compounds that contribute to the inhibition of neuroinflammation during stroke recovery through regulation of microglia polarization.

MATERIALS AND METHODS

The extracts of EW in different solvents were evaluated for their inhibitory ability of cytokine (IP-10) expression in LPS stimulated BV2 cells. The most effective extract (of petroleum ether extract) was further separated to 18 fractionations on a semi-preparative HPLC column, which were assess for the IP-10 down-regulation efficiency by RT-qPCR. The potent isolate was further fractionated in 12 fractions, which showed fewer peaks. The fraction 6 from this isolates, which remarkably down-regulates cytokines expression including IP-10, TNFα and IL-1β, was analyzed on UPLC-qTOF MS. The key chemicals were measured for their cytokine inhibition in BV2 cells and mouse primary microglia.

RESULTS

After two consecutive fractionating by preparative HPLC, petroleum ether extraction of EW gave 12 fractions with relatively distinctive chromatograms. A particular fraction (fraction 6) preserved the inhibitory effects on expression of pro-inflammatory cytokines including IP-10, TNFα, IL-1β and iNOS. The result of UPLC-qTOF MS analysis showed that the fraction contains 21 chemicals including costunolide, alantolactone, myristicin and linolenic acid, which significantly down-regulate the expression of key pro-inflammatory cytokines in LPS stimulated BV2 cells as well as mouse primary microglia.

CONCLUSION

Collectively our data suggest that the bioactive chemical pool which is responsible for the therapeutic effects of EW can be extracted in petroleum ether, and fractionated to a relatively small multiple components. Such components include known anti-inflammatory chemicals, which may contribute to the possible microglia polarization in brain lesion during the recovery of ischemic stroke.

Costunolide induces mitochondria-mediated apoptosis in human gastric adenocarcinoma BGC-823 cells

Background

Costunolide, a sesquiterpene lactone extracted from Radix Aucklandiae, has the activity against multiple cancers. However, the effect of costunolide on gastric cancer (GC) have remained to be ambiguous. In this study, we investigated the underlying mechanisms of apoptosis induced by costunolide in human gastric adenocarcinoma BGC-823 cells in vitro and in vivo.

Methods

The viability of BGC-823 cells was detected by MTT assay. The apoptosis and mitochondrial membrane potential (ΔΨm) of BGC-823 cells induced by costunolide were analyzed by flow cytometry. The inhibiton of costunolide on human gastric adenocarcinoma was estimated in xenografts in nude mice. Apoptosis related proteins and genes were detected by Western blot and Q-PCR.

Results

Costunolide inhibited the viability of BGC-823 cells in a time and concentration dependent manner. Costunolide induced the apoptosis and lowered the ΔΨm of BGC-823 cells significantly. Costunolide increased the expression of Bax, cleaved caspase 9, cleaved caspase 7, cleaved caspase 3 and cleaved poly ADP ribose polymerase (PARP) proteins and decreased the expression of Bcl-2, pro-caspase 9, pro-caspase 7, pro-caspase 3 and PARP proteins. Costunolide upregulated the expression of puma, Bak1 and Bax mRNA and downregulated the expression of Bcl-2 mRNA. In addition, we demonstrated that costunolide inhibited the growth and induced apoptosis of BGC-823 cells xenografted in athymic nude mice. Costunolide increased the expression of cleaved caspase 9, cleaved caspase 3 and Bax proteins and decreased the expression of Bcl-2 protein in xenografted tumor. Costunolide upregulated the expression of puma and Bax mRNA and decreased the expression of Bcl-2 mRNA in xenografted tumor.

Conclusions

Collectively, our results suggested that costunolide induced mitochondria-mediated apoptosis in human gastric adenocarcinoma BGC-823 cells and could be the candidate drug against GC in clinical practice.

Costunolide-A Bioactive Sesquiterpene Lactone with Diverse Therapeutic Potential

Sesquiterpene lactones constitute a major class of bioactive natural products. One of the naturally occurring sesquiterpene lactones is costunolide, which has been extensively investigated for a wide range of biological activities. Multiple lines of preclinical studies have reported that the compound possesses antioxidative, anti-inflammatory, antiallergic, bone remodeling, neuroprotective, hair growth promoting, anticancer, and antidiabetic properties. Many of these bioactivities are supported by mechanistic details, such as the modulation of various intracellular signaling pathways involved in precipitating tissue inflammation, tumor growth and progression, bone loss, and neurodegeneration. The key molecular targets of costunolide include, but are not limited to, intracellular kinases, such as mitogen-activated protein kinases, Akt kinase, telomerase, cyclins and cyclin-dependent kinases, and redox-regulated transcription factors, such as nuclear factor-kappaB, signal transducer and activator of transcription, activator protein-1. The compound also diminished the production and/expression of proinflammatory mediators, such as cyclooxygenase-2, inducible nitric oxide synthase, nitric oxide, prostaglandins, and cytokines. This review provides an overview of the therapeutic potential of costunolide in the management of various diseases and their underlying mechanisms.

DITMD-induced mitotic defects and apoptosis in tumor cells by blocking the polo-box domain-dependent functions of polo-like kinase 1

DITMD (1, 3- Dioxolo[4,5-g] isoquinolinium 5, 6, 7, 8- tetrahydro- 4- methoxy- 6, 6- dimethyl- 5- [2- oxo- 2- (2-pyridinyl)ethyl] - iodide) is a natural product-like compound with a hydrocotarnine moiety. The aim of this study was to investigate the anticancer effects of DITMD including mitotic arrest, apoptosis, radiosensitization, and to further explore its possible mechanism. DITMD (3-30 µM) induced an obvious cell cycle delay at G2/M transition and apoptosis in HeLa cells. In a validation study, DITMD caused chromosome alignment defects and accumulation of mitotic markers such as polo-like kinase 1, cyclin B1, and phospho-histone H3. DITMD pre-treatment for 11 h also significantly decreased the cells' survival after X-ray irradiation. In mechanism studies, DITMD inhibited the polo-box domain of polo-like kinase 1 but not the conserved kinase domain. Molecular modeling also suggests that DITMD binds at the phosphate group recognition site and inhibits the action on phospho-peptide ligands. In addition, DITMD was analyzed as a PLHSpT competitive inhibitor with an IC50 value of 2.1 μM and exhibited good selectivity against 105 distinct kinases. Taken together, these results indicate that DITMD induced chromosome alignment defects, apoptosis and radio-sensitization, and suggest that one mechanism underlying these anticancer effects involves inhibiting the polo-box domain-dependent functions of polo-like kinase 1.

Dehydrocostus Lactone Enhances Chemotherapeutic Potential of Doxorubicin in Lung Cancer by Inducing Cell Death and Limiting Metastasis

BACKGROUND Natural compounds have been utilized in inhibiting metastasis alone or in combination with other anti-tumor agents. Dehydrocostus lactone (DHC), a natural sesquiterpene lactone, was used to investigate its effect on proliferation of lung cancer cells and on the anti-angiogenic efficacy of doxorubicin. MATERIAL AND METHODS Cell proliferation was assessed by MTT assay and clonogenic assay. Apoptosis and migration were assessed by flow cytometry and wound-healing assay, respectively. Western blotting and qPCR were performed for gene and protein expression analysis. Matrigel plug assay was performed for angiogenesis assessment. RESULTS Results of the study show that DHC inhibited the survival and proliferation of lung cancer cells (A549 and H460) and enhanced the growth-inhibitory properties of DOX. Cotreatment of DHC enhanced the apoptosis-inducing effects of DOX by activating caspase-9 and caspase-3 followed by cleavage of PARP. Treatment of A549 and H460 cells with DHC caused suppression of HIF-1α, Akt and pAkt, GSK-3β and pGSK-3β, as well as ERK, pERK, mTOR, and p-mTOR. DHC enhanced the effect of DOX by inhibiting migration of A549 cells as observed by wound-healing assay. DHC caused synergistic inhibition of MMP-2 and MMP-9 genes when treated in combination with DOX. DHC further enhanced the anti-angiogenic properties of DOX in mice implanted with Matrigel plugs. DHC suppressed the proliferation of lung cancer cells and enhanced the anti-angiogenic properties of DOX. CONCLUSIONS The putative mechanism behind the metastasis-limiting effects of DHC may involve the suppression of Akt/GSK-3β and inhibition of MMP-2 and MMP-9 in lung cancer cells.

Differential Pharmacological Activities of Oxygen Numbers on the Sulfoxide Moiety of Wasabi Compound 6-(Methylsulfinyl) Hexyl Isothiocyanate in Human Oral Cancer Cells

6-(methylsulfinyl) hexyl isothiocyanate (6-MITC) is a naturally occurring compound isolated from Wasabia japonica (wasabi). The synthetic derivatives, 6-(methylsulfenyl) hexyl isothiocyanate (I7447) and 6-(methylsulfonyl) hexyl isothiocyanate (I7557), were derived from 6-MITC with the deletion and addition of oxygen, respectively. We aimed to evaluate the effect of these synthetic compounds on human oral cancer cells, SAS and OECM-1. All three compounds (I7447, 6-MITC, and I7557) inhibited the viability of SAS and OECM-1 cells using MTT assay. Morphological observations showed various proportions of mitotic arrest and apoptosis in cells treated with these compounds. Cell cycle analysis revealed relatively abundant G2/M arrest in 6-MITC and I7557-treated cells, whereas sub-G1 accumulation was found in I7447-treated cells. In using phosphorylated histone H3 as a marker for mitosis, the addition of 6-MITC and I7557 (excluding I7447) could be shown to arrest cells during mitosis. In contrast, I7447 induced more prominent apoptosis than the 6-MITC or I7557 compounds. The down-regulated expression of the phosphorylated form of CHK1 and Cdc25c was noted in 6-MITC and I7557-treated cells. I7557 could sensitize SAS cells to death by radiation. The wasabi compound, 6-MITC, and its chemical derivatives with different numbers of oxygen may have differential pharmacological effects on human oral cancer cells.

Synthesis and biological evaluation of α-santonin derivatives as anti-hepatoma agents

A series of α-santonin-derived compounds as potentially anti-hepatoma agents were designed and synthesized in an effort to find novel therapeutic agents. Among them, derivative 5h was more potent than the positive control 5-fluorouracil (5-Fu) on HepG-2, QGY-7703 and SMMC-7721 with IC₅₀ values of 7.51, 3.06 and 4.08 μM, respectively. The structure-activity relationships (SARs) of these derivatives were discussed. In addition, flow cytometry and western blot assay revealed that the derivatives induced hepatoma cells apoptosis by facilitating apoptosis-related proteins expressions. Our findings suggested that these α-santonin-derived analogues hold promise as chemotherapeutic agents for the treatment of human hepatocellular cancer.

Costunolide induces micronuclei formation, chromosomal aberrations, cytostasis, and mitochondrial-mediated apoptosis in Chinese hamster ovary cells

Costunolide (CE) is a sesquiterpene lactone well-known for its antihepatotoxic, antiulcer, and anticancer activities. The present study focused on the evaluation of the cytogenetic toxicity and cellular death-inducing potential of CE in CHO cells, an epithelial cell line derived from normal ovary cells of Chinese hamster. The cytotoxic effect denoting MTT assay has shown an IC₅₀ value of 7.56 μM CE, where 50% proliferation inhibition occurs. The oxidative stress caused by CE was confirmed based on GSH depletion induced cell death, conspicuously absent in N-acetylcysteine (GSH precursor) pretreated cells. The evaluation of genotoxic effects of CE using cytokinesis block micronucleus assay and chromosomal aberration test has shown prominent induction of binucleated micronucleated cells and aberrant metaphases bearing chromatid and chromosomal breaks, indicating CE's clastogenic and aneugenic potential. The apoptotic death in CE treated cells was confirmed by an increase in the number of cells in subG1 phase, exhibiting chromatin condensation and membranous phosphatidylserine translocation. The apoptosis induction follows mitochondrial mediation, evident from an increase in the BAX/Bcl-2 ratio, caspase-3/7 activity, and mitochondrial membrane permeability. CE also induces cytostasis in addition to apoptosis, substantiated by the reduced cytokinetic (replicative indices) and mitotic (mitotic indices and histone H3 Ser-10 phosphorylation) activities. Overall, the cellular GSH depletion and potential genotoxic effects by CE led the CHO cells to commit apoptosis and lowered cell division. The observed sensitivity of CHO cells doubts unintended adverse effects of CE on normal healthy cells, suggesting higher essentiality of further studies in order to establish its safety efficacy in therapeutic explorations.

The novel protein C9orf116 promotes rat liver cell line BRL-3A proliferation

Our previous study has proved that the chromosome 9 open reading frame 116 (C9orf116) (NM_001106564.1) was significantly up-regulated in the proliferation phase of liver regeneration. To study its possible physiological function, we analyzed the effect of C9orf116 on BRL-3A cells via over-expression and interference technique. MTT results showed that the cell viability of the interference group was significantly lower than the control group at 48h after transfection (P<0.05), whereas it was significantly higher in the over-expression group (P<0.05). The flow cytometry results showed that C9orf116 knockdown or over-expression had little effect on BRL-3A cell apoptosis. However, the number of cells in division phase (G2/M) was significantly reduced in the interference group (P<0.05), but significantly increased in the over-expression group (P<0.01). Furthermore, the expressions of cell proliferation-related genes CCNA2, CCND1 and MYC both at mRNA and protein levels were down-regulated in the interference group and up-regulated in the over-expression group. Therefore, we concluded that C9orf116 may promote cell proliferation by modulating cell cycle transition and the expression of key genes CCNA2, CCND1 and MYC in BRL-3A cells.

Aucklandia lappa DC. extract enhances gefitinib efficacy in gefitinib-resistance secondary epidermal growth factor receptor mutations

ETHNOPHARMACOLOGICAL RELEVANCE

Aucklandia lappa DC. is a widely used medicinal plant in China, India and Pakistan for a long time. Previously, a number of different pharmacological experiments in vitro and in vivo have convincingly demonstrated the abilities of it to exhibit anticancer activities. Reynoutria japonica Houtt. has also been widely used as traditional Chinese medicinal plant. Previous studies have demonstrated that it is bioactive to exhibit anticancer activities.

AIM OF THE STUDY

This study aims to investigate whether the extracts of Aucklandia lappa DC. and Reynoutria japonica Houtt. are capable of treating drug-resistant non-small cell lung cancer (NSCLC), providing support for novel usage beyond traditional uses.

MATERIALS AND METHODS

Extracts combined with gefitinib have been tested taking the vulval development of transgenic C. elegans (jgIs25) as an effective and simple in vivo model system, evaluating their efficacy against acquired NSCLC. Synchronous larval 1 (L1) larvae were treated with extracts plus gefitinib and cultured to obtain mainly L4 larvae. The multivulva (Muv) phenotype was recorded at the adult stage.

RESULTS

Our data showed that Aucklandia lappa DC. extract could significantly enhance the efficacy of gefitinib, suppressing the Muv phenotype of jgIs25. Meanwhile, it could also down-regulate the mRNA and protein expression of EGFR in jgIs25. Collectively, our results verified that the capability of Aucklandia lappa DC. to inhibit Muv phenotype may be based on the EGFR signaling pathway inhibition.

CONCLUSION

We demonstrated that the co-administration of Aucklandia lappa DC. with gefitinib may provide an effective strategy for the therapy of EGFR inhibitor resistant NSCLCs.

Dehydrocostus lactone, a natural sesquiterpene lactone, suppresses the biological characteristics of glioma, through inhibition of the NF-κB/COX-2 signaling pathway by targeting IKKβ

Dehydrocostus lactone (DHE), a natural sesquiterpene lactone, has been used for treatment of various diseases with its anti-inflammatory activity. Recently, it has caused extensive interest in researchers due to it has anti-cancer abilities in some types of carcinomas. However, the anti-cancer effect and mechanism of DHE in glioma remains unclear. The present study conducted to determine the biological effects of DHE on the glioblastoma cells, as well as the mechanisms underlying these effects. After treatment with DHE, the glioblastoma (U118, U251 or U87) cells were significantly inhibited in their viability, proliferation and migration. At the meantime, DHE also induced mitochondria-mediated apoptosis by promoting the release of cytochrome c into cytosol, which activating caspase signaling pathway. Furthermore, our results fully demonstrate that DHE significantly suppressed COX-2 expression by inhibiting the phosphorylation of IKKβ via targeting the ATP-binding site, thereby abrogating NF-κB binding and p300 recruitment to COX-2 promoter. Moreover, the current study firstly demonstrated that DHE can cross blood-brain barrier (BBB). In addition, treatment with DHE markedly inhibited neoplastic weight and volume without the notable adverse effects in the xenograft nude mice model, and these effects may be mediated through inhibition of the IKKβ/NF-κB/COX-2 signaling pathway. These findings provide the pharmacological evidence for development of DHE as a potential agent against glioma.

CMA down-regulates p53 expression through degradation of HMGB1 protein to inhibit irradiation-triggered apoptosis in hepatocellular carcinoma

AIM

To investigate the mechanism of chaperone-mediated autophagy (CMA)-induced resistance to irradiation-triggered apoptosis through regulation of the p53 protein in hepatocellular carcinoma (HCC).

METHODS

Firstly, we detected expression of lysosome-associated membrane protein 2a (Lamp-2a), which is the key protein of CMA, by western blot in HepG2 and SMMC7721 cells after irradiation. We further used shRNA Lamp-2a HCC cells to verify the radioresistance induced by CMA. Next, we detected the HMGB1 and p53 expression after irradiation by western blot, and we further used RNA interference and ethyl pyruvate (EP), as a HMGB1 inhibitor, to observe changes of p53 expression. Finally, an immunoprecipitation assay was conducted to explore the interaction between Lamp-2a and HMGB1, and the data were analyzed.

RESULTS

We found the expression of Lamp-2a was increased on irradiation while apoptosis decreased in HepG2 and SMMC7721 cells. The apoptosis was increased markedly in the shRNA Lamp-2a HepG2 and SMMC7721 cells as detected by western blot and colony formation assay. Next, we found p53 expression was gradually reduced on irradiation but obviously increased in shRNA Lamp-2a cells. Furthermore, p53 increased the cell apoptosis on irradiation in Hep3B (p53-/-) cells. Finally, p53 levels were regulated by HMGB1 as measured through RNA interference and the EP treatment. HMGB1 was able to combine with Lamp-2a as seen by immunoprecipitation assay and was degraded via the CMA pathway. The decreased HMGB1 inhibited p53 expression induced by irradiation and further reduced the apoptosis in HCC cells.

CONCLUSION

CMA pathway activation appears to down-regulate the susceptibility of HCC to irradiation by degrading HMGB1 with further impact on p53 expression. These findings have clinical relevance for radiotherapy of HCC.

Emerging Anti-Mitotic Activities and Other Bioactivities of Sesquiterpene Compounds upon Human Cells

We review the bio-activities of natural product sesquiterpenes and present the first description of their effects upon mitosis. This type of biological effect upon cells is unexpected because sesquiterpenes are believed to inactivate proteins through Michael-type additions that cause non-specific cytotoxicity. Yet, certain types of sesquiterpenes can arrest cells in mitosis as measured by cell biology, biochemical and imaging techniques. We have listed the sesquiterpenes that arrest cells in mitosis and analyzed the biological data that support those observations. In view of the biochemical complexity of mitosis, we propose that a subset of sesquiterpenes have a unique chemical structure that can target a precise protein(s) required for mitosis. Since the process of mitotic arrest precedes that of cell death, it is possible that some sesquiterpenes that are currently classified as cytotoxic might also induce a mitotic arrest. Our analysis provides a new perspective of sesquiterpene chemical biology.

Costunolide and dehydrocostuslactone combination treatment inhibit breast cancer by inducing cell cycle arrest and apoptosis through c-Myc/p53 and AKT/14-3-3 pathway

Our previous studies demonstrated that volatile oil from saussurea lappa root (VOSL), rich in two natural sesquiterpene lactones, costunolide (Cos) and dehydrocostuslactone (Dehy), exerts better anti-breast cancer efficacy and lower side effects than Cos or Dehy alone in vivo, however, their anti-cancer molecular mechanisms were still unknown. In this study, we investigated the underlying mechanisms of Cos and Dehy combination treatment (CD) on breast cancer cells through proteomics technology coupled with Western blot validation. Ingenuity Pathways Analysis (IPA) results based on the differentially expressed proteins revealed that both VOSL and CD affect the 14-3-3-mediated signaling, c-Myc mediated apoptosis signaling and protein kinase A (PKA) signaling. Western blot coupled with cell cycle and apoptosis analysis validated the results of proteomics analysis. Cell cycle arrest and apoptosis were induced in a dose-dependent manner, and the expressions of p53 and p-14-3-3 were significantly up-regulated, whereas the expressions of c-Myc, p-AKT, p-BID were significantly down-regulated, furthermore, the ratio of BAX/BCL-2 were significantly increased in breast cancer cells after CD and VOSL treatment. The findings indicated that VOSL and CD could induce breast cancer cell cycle arrest and apoptosis through c-Myc/p53 and AKT/14-3-3 signaling pathways and may be novel effective candidates for breast cancer treatment.

Upregulation of Long Noncoding RNA Small Nucleolar RNA Host Gene 18 Promotes Radioresistance of Glioma by Repressing Semaphorin 5A

PURPOSE

Although increasing evidence has shown that long noncoding RNAs play an important regulatory role in carcinogenesis and tumor progression, little is known about the role of small nucleolar RNA host gene 18 (SNHG18) in cancer. The goal of this study was to investigate the expression of SNHG18 and its clinical significance in glioma.

METHODS AND MATERIALS

Differences in the lncRNA expression profile between M059K and M059J cells were assessed by lncRNA expression microarray analysis. The expression and localization of SNHG18 in glioma cells or tissues was evaluated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and in situ hybridization (ISH), respectively. the clinical associations of SNHG18 in glioma was evaluated by qRT-PCR, ISH and immunohistochemistry. The role of SNHG18 in glioma radiosensitivity was evaluated by colony formation assays, immunofluorescence, Western blot and tumor growth inhibition study.

RESULTS

The present study investigated the clinical associations of SNHG18 and its role in glioma. Our results showed that the expression of SNHG18 was remarkably upregulated in clinical glioma tissues compared with normal brain tissues. SNHG18 expression was associated with the clinical tumor grade and correlated negatively with isocitrate dehydrogenase 1 mutation. In addition, knockdown of SNHG18 with short hairpin RNA suppressed the radioresistance of glioma cells, and transgenic expression of SNHG18 had the opposite effect. Furthermore, xenograft tumors grown from cells with SNHG18 deletion were more radiosensitive than tumors grown from control cells. Further studies revealed that SNHG18 promotes radioresistance by inhibiting semaphorin 5A and that inhibition of semaphorin 5A expression abrogated the radiosensitizing effect caused by SNHG18 deletion.

CONCLUSIONS

Our findings provide new insights into the role of SNHG18 in glioma and suggest its potential as a target for glioma therapy.

TAT-ODD-p53 enhances the radiosensitivity of hypoxic breast cancer cells by inhibiting Parkin-mediated mitophagy

Radiation therapy has an important role in the treatment of breast cancer. Dysfunction p53 and hypoxia are typical biological characteristics of breast cancer that constitute barriers to the efficacy of radiotherapy. Mitophagy plays a protective role in cellular homeostasis under hypoxic conditions, while mitophagy is inhibited by p53 in normal cells. We explored the effects of a p53 fusion protein, TAT-ODD-p53, on the radiosensitivity of hypoxic breast cancer cells both in vitro and in vivo, as well as investigating the related molecular mechanisms. We found that selective accumulation of TAT-ODD-p53 occurred under hypoxic conditions and significantly increased tumor cell radiosensitivity both in vitro and in vivo. Mitophagy had an important role in maintaining hypoxia-induced radioresistance. Mitophagy was inhibited by TAT-ODD-p53 and this inhibition was suppressed by over-expression of Parkin in hypoxic irradiated breast cancer cells. In addition, mitophagy was induced by deletion of p53, with this effect being weakened by Parkin knockdown at a low oxygen tension. By interacting with Parkin, p53 inhibited the translocation of Parkin to the mitochondria, disrupting the protective mitophagy process. These results suggest that TAT-ODD-p53 has a significant and preferential radiosensitizing effect on hypoxic breast cancer cells by inhibition of Parkin-mediated mitophagy.

Costunolide induces G1/S phase arrest and activates mitochondrial-mediated apoptotic pathways in SK-MES 1 human lung squamous carcinoma cells

Despite the availability of several therapeutic options, a safer and more effective modality strategy is required for the treatment of lung cancer. Costunolide, a sesquiterpene lactone which isolated from the Saussurea lappa, has potent anticancer properties. In the present study, the effects of costunolide on cell viability, the cell cycle and apoptosis in SK-MES-1 human lung squamous carcinoma cells were investigated. Costunolide induced morphological changes and inhibited growth of SK-MES-1 cells growth. Flow cytometric analysis data demonstrated that costunolide significantly induced apoptosis of SK-MES-1 cells and induced cell cycle arrest at G1/S phase in a dose-dependent manner. Through upregulation in the expression of p53 and Bax, and downregulation in the expression of Bcl-2 and activation of caspase-3, costunolide-induced apoptosis was confirmed by western blot analysis. In addition, the significant loss of mitochondrial membrane potential indicated that costunolide may induce apoptosis via the mitochondria-dependent pathway in SK-MES-1 cells. These results highlight the potential effects of costunolide as an anti-cancer agent in a human lung squamous carcinoma cell line.

Cytotoxic Impact of Costunolide Isolated from Costus speciosus on Breast Cancer via Differential Regulation of Cell Cycle-An In-vitro and In-silico Approach

Costunolide, a sesquiterpene lactone, is a biologically active molecule found in most of the medicinally valuable plants. The present study aims to evaluate the anticancer property of costunolide isolated from Costus speciosus against breast cancer cell lines (MCF-7 and MDA-MB-231). Costunolide effectively reduced the viability of both MCF-7 and MDA-MB-231 cell lines at an IC50 value of 40 μM. Flow cytometric analysis revealed costunolide mediated cell cycle arrest at G2/M phase in both the cell types. Western blotting results confirmed the alterations in the expression of cell cycle regulators (cyclin D1, D3, CDK-4, CDK-6, p18 INK4c, p21 CIP1/Waf-1 and p27 KIP1) and apoptosis inducers (caspase-3 and caspase-9) upon costunolide treatment in comparison with their expressions in normal breast cell line (MCF-10A). Costunolide mediated downregulation of positive cell cycle regulators and upregulation of negative cell cycle regulators were related to the induction of apoptosis in cancer cells. The above results were validated with in-silico results that predicted stable interactions between costunolide and cancer targets. Thus costunolide effectively induced breast cancer cell apoptosis targeting cell cycle regulation, and the compound can be used as an effective herbal therapeutic molecule to treat breast cancer with further explorations.

Potential anti-cancer activities and mechanisms of costunolide and dehydrocostuslactone

Costunolide (CE) and dehydrocostuslactone (DE) are derived from many species of medicinal plants, such as Saussurea lappa Decne and Laurus nobilis L. They have been reported for their wide spectrum of biological effects, including anti-inflammatory, anticancer, antiviral, antimicrobial, antifungal, antioxidant, antidiabetic, antiulcer, and anthelmintic activities. In recent years, they have caused extensive interest in researchers due to their potential anti-cancer activities for various types of cancer, and their anti-cancer mechanisms, including causing cell cycle arrest, inducing apoptosis and differentiation, promoting the aggregation of microtubule protein, inhibiting the activity of telomerase, inhibiting metastasis and invasion, reversing multidrug resistance, restraining angiogenesis has been studied. This review will summarize anti-cancer activities and associated molecular mechanisms of these two compounds for the purpose of promoting their research and application.

Antihormonal agents as a strategy to improve the effect of chemo-radiation in cervical cancer: in vitro and in vivo study

Background

Over the past few years, the concurrent use of cisplatin-based chemotherapy and radiation therapy has dramatically improved the local response and increased overall survival in early-stage cervical cancer. However, for the advanced stages of the disease this standard treatment has proved insufficient. We investigated the capacity of Mifepristone and ICI 182,780, which are anti-progestin and anti-estrogen drugs, respectively, to act as chemo-radiosensitizing agents in cervical cancer cells and cervix xenografts.

Methods

The effect of chemo-radiation alone or combined with Mifepristone or ICI 182,780 was evaluated in HeLa cells and with tumor growth in cervix xenografts. After concomitant chemo-radiotherapy, the effect of each of these antihormonal agents on apoptosis (determined by Annexing V assay) and the cell cycle phases were determined by flow cytometry. The expression of angiogenic factor VEGF in tumor samples was determined using quantitative RT-PCR analysis of VEGF gene expression.

Results

Compared to radiation alone or radiation/cisplatin therapy, there was significantly higher cytotoxicity and a greater antitumoral effect with the combined application of radiation/cisplatin and Mifepristone or ICI 182,780. Analyses of the apoptosis and cell cycle demonstrated changes only with ICI, not with Mifepristone, when was applied in combination with radiation/cisplatin. The analysis of VEGF mRNA expression levels in tumors at the end of the study demonstrated a significant inhibition, compared to radiation only or the radiation/cisplatin treatment, after concurrent chemo-radiotherapy and each one of the antihormonal drugs.

Conclusion

Mifepristone and ICI 182,780 may be potentially promising chemo-radiosensitizing compounds to be used in combination with ionizing irradiation and cisplatin in the treatment of patients with advanced cervical cancer.

WNT activation by lithium abrogates TP53 mutation associated radiation resistance in medulloblastoma

TP53 mutations confer subgroup specific poor survival for children with medulloblastoma. We hypothesized that WNT activation which is associated with improved survival for such children abrogates TP53 related radioresistance and can be used to sensitize TP53 mutant tumors for radiation. We examined the subgroup-specific role of TP53 mutations in a cohort of 314 patients treated with radiation. TP53 wild-type or mutant human medulloblastoma cell-lines and normal neural stem cells were used to test radioresistance of TP53 mutations and the radiosensitizing effect of WNT activation on tumors and the developing brain. Children with WNT/TP53 mutant medulloblastoma had higher 5-year survival than those with SHH/TP53 mutant tumours (100% and 36.6% ± 8.7%, respectively (p < 0.001)). Introduction of TP53 mutation into medulloblastoma cells induced radioresistance (survival fractions at 2Gy (SF2) of 89% ± 2% vs. 57.4% ± 1.8% (p < 0.01)). In contrast, β-catenin mutation sensitized TP53 mutant cells to radiation (p < 0.05). Lithium, an activator of the WNT pathway, sensitized TP53 mutant medulloblastoma to radiation (SF2 of 43.5% ± 1.5% in lithium treated cells vs. 56.6 ± 3% (p < 0.01)) accompanied by increased number of γH2AX foci. Normal neural stem cells were protected from lithium induced radiation damage (SF2 of 33% ± 8% for lithium treated cells vs. 27% ± 3% for untreated controls (p = 0.05). Poor survival of patients with TP53 mutant medulloblastoma may be related to radiation resistance. Since constitutive activation of the WNT pathway by lithium sensitizes TP53 mutant medulloblastoma cells and protect normal neural stem cells from radiation, this oral drug may represent an attractive novel therapy for high-risk medulloblastomas.

Inhibition of inflammatory and proliferative responses of human keratinocytes exposed to the sesquiterpene lactones dehydrocostuslactone and costunolide

The imbalance of the intracellular redox state and, in particular, of the glutathione (GSH)/GSH disulfide couple homeostasis, is involved in the pathogenesis of a number of diseases. In many skin diseases, including psoriasis, oxidative stress plays an important role, as demonstrated by the observation that treatments leading to increase of the local levels of oxidant species ameliorate the disease. Recently, dehydrocostuslactone (DCE) and costunolide (CS), two terpenes naturally occurring in many plants, have been found to exert various anti-inflammatory and pro-apoptotic effects on different human cell types. These compounds decrease the level of the intracellular GSH by direct interaction with it, and, therefore, can alter cellular redox state. DCE and CS can trigger S-glutathionylation of various substrates, including the transcription factor STAT3 and JAK1/2 proteins. In the present study, we investigated on the potential role of DCE and CS in regulating inflammatory and proliferative responses of human keratinocytes to cytokines. We demonstrated that DCE and CS decreased intracellular GSH levels in human keratinocytes, as well as inhibited STAT3 and STAT1 phosphorylation and activation triggered by IL-22 or IFN-γ, respectively. Consequently, DCE and CS decreased the IL-22- and IFN-γ-induced expression of inflammatory and regulatory genes in keratinocytes, including CCL2, CXCL10, ICAM-1 and SOCS3. DCE and CS also inhibited proliferation and cell-cycle progression-related gene expression, as well as they promoted cell cycle arrest and apoptosis. In parallel, DCE and CS activated the anti-inflammatory EGFR and ERK1/2 molecules in keratinocytes, and, thus, wound healing in an in vitro injury model. In light of our findings, we can hypothesize that the employment of DCE and CS in psoriasis could efficiently counteract the pro-inflammatory effects of IFN-γ and IL-22 on keratinocytes, revert the apoptosis-resistant phenotype, as well as inhibit hyperproliferation in the psoriatic epidermis.

Targeting apoptosis pathways in cancer and perspectives with natural compounds from mother nature

Although the incidences are increasing day after day, scientists and researchers taken individually or by research group are trying to fight against cancer by several ways and also by different approaches and techniques. Sesquiterpenes, flavonoids, alkaloids, diterpenoids, and polyphenolic represent a large and diverse group of naturally occurring compounds found in a variety of fruits, vegetables, and medicinal plants with various anticancer properties. In this review, our aim is to give our perspective on the current status of the natural compounds belonging to these groups and discuss their natural sources, their anticancer activity, their molecular targets, and their mechanism of actions with specific emphasis on apoptosis pathways, which may help the further design and conduct of preclinical and clinical trials. Unlike pharmaceutical drugs, the selected natural compounds induce apoptosis by targeting multiple cellular signaling pathways including transcription factors, growth factors, tumor cell survival factors, inflammatory cytokines, protein kinases, and angiogenesis that are frequently deregulated in cancers and suggest that their simultaneous targeting by these compounds could result in efficacious and selective killing of cancer cells. This review suggests that they provide a novel opportunity for treatment of cancer, but clinical trials are still required to further validate them in cancer chemotherapy.

Sesquiterpenoids in subtribe Centaureinae (Cass.) Dumort (tribe Cardueae, Asteraceae): distribution, (13)C NMR spectral data and biological properties

Asteraceae Bercht. & J. Presl is one of the biggest and most economically important plant families. The taxonomy and phylogeny of Asteraceae is rather complex and according to the latest and most reliable taxonomic classification of Panero & Funk, based on the analysis of nine chloroplast regions, the family is divided into 12 subfamilies and 35 tribes. One of the largest tribes of Asteraceae is Cardueae Cass. with four subtribes (Carlininae, Echinopinae, Carduinae and Centaureinae) and more than 2500 species. Susanna & Garcia-Jacas have organized the genera of Centaureinae (about 800 species) into seven informal groups, which recent molecular studies have confirmed: 1. Basal genera; 2. Volutaria group; 3. Rhaponticum group; 4. Serratula group; 5. Carthamus group; 6. Crocodylium group; 7. Centaurea group. This review summarizes reports on sesquiterpenoids from the Centaureinae subtribe of the Asteraceae family, as well as the (13)C NMR spectral data described in the literature. It further reviews studies concerning the biological activities of these metabolites. For this work, literature data on sesquiterpenes from the Centaureinae subtribe were retrieved with the help of the SciFinder database and other similar data banks. All entries from 1958 until the end of 2011 were considered. This review is addressed to scientists working in the metabolomics field such as chemists, botanists, etc., the spectroscopic data reported make this work a good tool for structural elucidation, the biological section gives useful information to those who wish to study the structure activity relationships.

The radiosensitizing effect of Paeonol on lung adenocarcinoma by augmentation of radiation-induced apoptosis and inhibition of the PI3K/Akt pathway

PURPOSE

To investigate the radiosensitizing effect and mechanism of action by the natural product Paeonol on lung adenocarcinoma both in vitro and in vivo.

MATERIALS AND METHODS

Two lung adenocarcinoma cell lines (human lung adenocarcinoma cell line A549 and mouse Lewis lung carcinoma (LLC) cell line) were chosen for this research. In order to select the experimental concentrations of Paeonol, cytotoxicity was determined using a MTT (3-[4,5-dimethylthiazol-2-yl]-2,5- diphenyltetrazolium bromide) assay. A clonogenic assay was performed to measure the radiosensitizing effects. Apoptosis was determined by the Tunel (terminal deoxynucleotidyl transferase-mediated dUTP nick and labeling) assay and flow cytometry. Protein expression was analyzed by Western blotting. To test the radiosensitizing effect in vivo, a transplanted tumor model was established.

RESULTS

The MTT assay showed that Paeonol inhibited proliferation of cells. Paeonol concentration ranged from an IC5 (5% inhibiting concentration) to an IC20 and was used at non-toxic concentrations for subsequent experiments. The clonogenic assay showed that Paeonol enhanced the radiosensitivity of cells. Data from the Tunel assay and flow cytometry verified that Paeonol enhanced radiation-induced apoptosis. Paeonol inhibited the activation of the PI3K/AKT (Phosphatidylinositol 3-kinase/ Protein Kinase B) pathway and down-regulated the expression of COX-2 (Cyclooxygenase-2) and Survivin. Paeonol (1718 mg/kg) combined with 10 Gy irradiation inhibited the growth of a transplanted tumor model in vivo, resulting in the longest tumor growth time, tumor growth delay and the highest inhibition ratio when compared with the radiotherapy alone group.

CONCLUSIONS

It is reported for the first time that Paeonol has a radiosensitizing effect on lung adenocarcinoma both in vitro and in vivo. This effect could be related to the augmentation of radiation-induced apoptosis and the inhibition of the PI3K/Akt signalling pathway and its downstream proteins: COX-2 and Survivin.

Tumor dynamics in response to antiangiogenic therapy with oral metronomic topotecan and pazopanib in neuroblastoma xenografts

Metronomic chemotherapy, combined with targeted antiangiogenic drugs, has demonstrated significant anticancer efficacy in various studies. Though, tumors do acquire resistance. Here, we have investigated the effect of prolonged therapy with oral metronomic topotecan and pazopanib on tumor behavior in a neuroblastoma mouse xenograft model. SK-N-BE(2) xenograft-bearing mice were treated with either of the following regimens (daily, orally): vehicle (control), 150 mg/kg pazopanib, 1.0 mg/kg topotecan, and combination of topotecan and pazopanib. Planned durations of treatment for each regimen were 28, 56, and 80 days or until the end point, after which animals were sacrificed. We found that only combination-treated animals survived until 80 days. Combination halted tumor growth for up to 50 days, after which gradual growth was observed. Unlike single agents, all three durations of combination significantly lowered microvessel densities compared to the control. However, the tumors treated with the combination for 56 and 80 days had higher pericyte coverage compared to control and those treated for 28 days. The proliferative and mitotic indices of combination-treated tumors were higher after 28 days of treatment and comparable after 56 days and 80 days of treatment compared to control. Immunohistochemistry, Western blot, and real-time polymerase chain reaction revealed that combination treatment increased the hypoxia and angiogenic expression. Immunohistochemistry for Glut-1 and hexokinase II expression revealed a metabolic switch toward elevated glycolysis in the combination-treated tumors. We conclude that prolonged combination therapy with metronomic topotecan and pazopanib demonstrates sustained antiangiogenic activity but also incurs resistance potentially mediated by elevated glycolysis.

Antitumour effect of sesquiterpene (+)-chabranol on four human cancer cell lines by inducing apoptosis and autophagy

OBJECTIVE

To investigate the effects and mechanisms of sesquiterpene (+)-chabranol on proliferation of a panel of four human tumour cell lines (BGC-823, SGC-7901, SSMC-7721 and HepG2).

METHODS

Cell viability was assessed using a standard methyltetrazolium assay; cell-cycle analysis of BGC-823 cells was performed by flow cytometry. Transmission electron microscopy (TEM) was used to examine the ultrastructure of BGC-823 cells exposed to (+)-chabranol. Apoptosis was investigated by evaluating DNA laddering, using gel electrophoresis.

RESULTS

(+)-Chabranol had a marked time- and concentration-dependent inhibitory effect on BGC-823 cell proliferation. The effect was less marked in SGC-7901, SSMC-7721 and HepG2 cells. Exposure of BGC-823 cells to (+)-chabranol arrested the cell cycle at G(1). Evidence of apoptosis and autophagy was observed by TEM; DNA laddering in BGC-823 cells supported the presence of apoptosis.

CONCLUSIONS

This study suggested that (+)-chabranol has antitumour activity against BGC-823 cells, and may exert its action by inhibition of proliferation and induction of apoptosis and autophagy. With further development, (+)-chabranol may represent a potential novel treatment for poorly differentiated gastric cancer.

Induction of G₂/M arrest, caspase activation and apoptosis by α-santonin derivatives in HL-60 cells

Sesquiterpene lactones (SLs) are natural products with a variety of biological activities. Previously, we demonstrated the cytotoxic effects of three new α-santonin derivatives on different tumor cell lines with low toxic effects upon peripheral human leukocytes. Here, we evaluated the mechanism of action triggered by these derivatives. HL-60 cell cycle determined after 24h treatment revealed a significant inhibition on cell-cycle progression and leading to an increasing of cells in G2/M [7.6% and 9.0% for compound 3% and 9.0% and 8.6% for compound 4 (1 and 2 μM, respectively)]. However, after 48 h exposure, all compounds caused G2/M reduction and a significant DNA fragmentation. Compounds 2, 3 and 4 were able to induce apoptosis on leukemia cells, which was corroborated by phosphatidyserine externalization and activation of caspases-3 and -7 after 24h exposure. None of the derivatives analyzed caused depolarization of mitochondrial membrane within 24h of incubation, suggesting the involvement of the extrinsic apoptotic pathway in the death process. The antiproliferative action of these compounds is related to the DNA synthesis inhibition and cell cycle arrest, which probably lead to apoptosis activation. Therefore, these santonin derivatives are promising lead candidates for development of new cytotoxic agents.