Β-elemene inhibits Hsp90/Raf-1 molecular complex inducing apoptosis of glioblastoma cells

Beta-elemene: A phytochemical with promise as a drug candidate for tumor therapy and adjuvant tumor therapy

BACKGROUND

β-Elemene (IUPAC name: (1 S,2 S,4 R)-1-ethenyl-1-methyl-2,4-bis(prop-1-en-2-yl) cyclohexane), is a natural compound found in turmeric root. Studies have demonstrated its diverse biological functions, including its anti-tumor properties, which have been extensively investigated. However, these have not yet been reviewed. The aim of this review was to provide a comprehensive summary of β-elemene research, with respect to disease treatment.

METHODS

β-Elemene-related articles were found in PubMed, ScienceDirect, and Google Scholar databases to systematically summarize its structure, pharmacokinetics, metabolism, and pharmacological activity. We also searched the Traditional Chinese Medicine System Pharmacology database for therapeutic targets of β-elemene. We further combined these targets with the relevant literature for KEGG and GO analyses.

RESULTS

Studies on the molecular mechanisms underlying β-elemene activity indicate that it regulates multiple pathways, including STAT3, MAPKs, Cyclin-dependent kinase 1/cyclin B, Notch, PI3K/AKT, reactive oxygen species, METTL3, PTEN, p53, FAK, MMP, TGF-β/Smad signaling. Through these molecular pathways, β-elemene has been implicated in tumor cell proliferation, apoptosis, migration, and invasion and improving the immune microenvironment. Additionally, β-elemene increases chemotherapeutic drug sensitivity and reverses resistance by inhibiting DNA damage repair and regulating pathways including CTR1, pak1, ERK1/2, ABC transporter protein, Prx-1 and ERCC-1. Nonetheless, owing to its lipophilicity and low bioavailability, additional structural modifications could improve the efficacy of this drug.

CONCLUSION

β-Elemene exhibits low toxicity with good safety, inhibiting various tumor types via diverse mechanisms in vivo and in vitro. When combined with chemotherapeutic drugs, it enhances efficacy, reduces toxicity, and improves tumor killing. Thus, β-elemene has vast potential for research and development.

Hsp90 protected chicken primary myocardial cells from heat-stress injury by inhibiting oxidative stress and calcium overload in mitochondria

Severe heat stress can cause human and animal heart failure and sudden death, which is an important issue of public health worldwide. Our previous studies in animals showed that myocardial cells injury was critical in the above process, and Hsp90 induction has a definite anti-myocardial injury effect, especially through aspirin (ASA). But the mechanism has not been fully clarified. In this study, an in vitro heat stress model of chicken primary myocardial cells (CPMCs) most sensitive to heat stress was used to explore the cell injuries and corresponding molecular resistance mechanism. We found that heat stress resulted in serious oxidation stress and calcium overload in mitochondria, which destroyed the mitochondrial structure and function and then triggered the cell death mechanism of CPMCs. Hsp90 was proven to be a central regulator for resisting heat-stress injury in CPMCs mitochondria using its inhibitor and inducer (geldanamycin and ASA), respectively. The mechanism involved that Hsp90 could activate Akt and PKM2 signals to promote Bcl-2 translocation into mitochondria and its phosphorylation, thereby preventing ROS production and subsequent cell apoptosis. In addition, Hsp90 inhibited mitochondrial calcium overload to overcome MPTP opening and MMP suppression through the inhibitory effect of Raf-1-ERK activation on the CREB-IP3R pathway. This study is the first to reveal a pivotal reason for heat-stressed damage in chicken myocardial cells at subcellular level and identify an effective regulator, Hsp90, and its protective mechanisms responsible for maintaining mitochondrial homeostasis.

MiR-302c-5p affects the stemness and cisplatin resistance of nasopharyngeal carcinoma cells by regulating HSP90AA1

Nasopharyngeal carcinoma (NPC) is one of the most frequent malignant tumors diagnosed in China. Cisplatin is one of the most commonly used anticancer drugs containing platinum in combined chemotherapy. The molecular mechanism of NPC is still largely unknown, and we aim to spare no effort to elucidate it. Normal human nasopharyngeal epithelial cells and NPC cell lines were cultured. The expression levels of miR-302c-5p and HSP90AA1 were detected with quantitative real-time PCR. Western blotting was used to analyze levels of the HSP90AA1, protein kinase B (AKT), p-AKT, CD44 and SOX2 proteins. The interaction between miR-302c-5p and HSP90AA1 was detected using a luciferase reporter assay. The bicinchoninic acid assay was used to observe cisplatin resistance in NPC cells. Our records confirmed that the expression of miR-302c-5p was substantially reduced and HSP90AA1 was increased in NPC cells. Additionally, miR-302c-5p inhibited cisplatin resistance and the traits of stem cells in NPC. A luciferase assay confirmed that miR-302c-5p is bound to HSP90AA1. Overexpression of HSP90AA1 may reverse the effects of overexpressed miR-302c-5p and inhibit cisplatin resistance and stem cell traits of NPC. This study investigated whether miR-302c-5p inhibited the AKT pathway by regulating HSP90AA1 expression and altered the resistance of NPC cells to cisplatin and the traits of tumor stem cells, which has not yet been reported.

β-elemene combined with temozolomide in treatment of brain glioma

Temozolomide (TMZ) is a widely used chemotherapeutic agent for malignant glioma. β-Elemene has been reported to have the ability of passing through the blood-brain barrier and reverse multidrug resistance. In the present study, transport of drugs through the in vitro blood-brain barrier (BBB) model also suggested that β-elemene can assist in TMZ transport to the brain. Plasma and brain pharmacokinetics demonstrated that when β-elemene is used in combination with TMZ, the metabolic rate of TMZ in plasma is slowed, and mean residence time (MRT) in brain is prolonged. The brain tissue distribution at 1 h indicated that the combination of TMZ and β-elemene promotes the distribution of β-elemene in the brain but slightly reduces the distribution of TMZ in the brain. Furthermore the antitumor effect and toxicity in vivo were also investigated. The combination of β-elemene and TMZ was well tolerated and significantly inhibited tumor growth in glioma xenografts. In summary, the present study indicates a synergistic antitumor effect of β-elemene and TMZ in glioma.

A Comprehensive Mini-Review of Curcumae Radix: Ethnopharmacology, Phytochemistry, and Pharmacology

Curcumae Radix is an efficacious ingredient with various medicinal properties empirically used in traditional Chinese medicine (TCM) formula for the treatment of cancer, depression, chest pain, dysmenorrhea, epilepsy, and jaundice. However, either phytochemical or pharmacological information of Curcumae Radix underlying its traditionally medicinal uses is rarely summarized and systematically analyzed. To provide evidence for clinical trials, a comprehensive literature review has been prepared of the phytochemicals, and ethnopharmacological and pharmacological mechanisms of this herb. The review approach consisted of searching several web-based scientific databases, including PubMed, Web of Science, and Elsevier. The keywords included “Curcumae Radix,” “ Curcuma wenyujin,” “ Curcuma longa,” “ Curcuma kwangsiensis,” and “ Curcuma phaeocaulis.” Based on the proposed criteria, 57 articles were evaluated in detail. The accumulated data indicate that Curcumae Radix contains a number of bioactive phytochemicals, mainly sesquiterpenes, diarylheptanoids, and diarylpentanoids, which account for a variety of medicinal values, such as anticancer, anti-inflammation, anti-hepatic fibrosis, and antioxidant. A wide range of apoptotic proteins, cell adhesion molecules, inflammatory cytokines, and enzymic and nonenzymic antioxidants could be modulated by either Curcumae Radix or its bioactive compounds, thus underpinning a fundamental understanding for the pharmacological effects of this herb. This review highlights the therapeutic potential of Curcumae Radix to progress the development of versatile adjuvants or therapeutic agents in the future.

Terpenoids from Curcumae Rhizoma: Their anticancer effects and clinical uses on combination and versus drug therapies

Cancer is a fatal disease with high mortality and low survival rate worldwide. At present, there is still no known cure for most cancers. Traditional Chinese medicine (TCM) represents a noteworthy reservoir for anticancer agents in drug discovery and development. Curcumae Rhizoma (called Ezhu in Chinese) is widely prescribed in TCM for anticancer therapy owing to its broad-spectrum antineoplastic activities. Especially, the terpenoids isolated from the essential oil of Curcumae Rhizoma form an integral part of cancer research and are well established as a potential anticancer agent. For example, β-elemene has been developed into a new drug for the treatment of solid tumors in China, and is currently undergoing clinical trials in the United States. The review aims to systematically summarize the recent advances on the anticancer effects and related molecular mechanisms of Curcumae Rhizoma, and its terpenoids (β-elemene, Furanodiene, Furanodienone, Germacrone, Curcumol, Curdione). In addition, we evaluated and compared the anticancer efficacy and clinical use of the terpenoids with combination therapies and traditional therapies. Therefore, this review provides sufficient evidence for the anticancer therapeutic potential of Curcumae Rhizoma and its terpenoids, and will contribute to the development of potential anticancer drugs.

Anti-Tumor Drug Discovery Based on Natural Product β-Elemene: Anti-Tumor Mechanisms and Structural Modification

Natural products are important sources for drug discovery, especially anti-tumor drugs. β-Elemene, the prominent active ingredient extract from the rhizome of Curcuma wenyujin, is a representative natural product with broad anti-tumor activities. The main molecular mechanism of β-elemene is to inhibit tumor growth and proliferation, induce apoptosis, inhibit tumor cell invasion and metastasis, enhance the sensitivity of chemoradiotherapy, regulate the immune system, and reverse multidrug resistance (MDR). Elemene oral emulsion and elemene injection were approved by the China Food and Drug Administration (CFDA) for the treatment of various cancers and bone metastasis in 1994. However, the lipophilicity and low bioavailability limit its application. To discover better β-elemene-derived anti-tumor drugs with satisfying drug-like properties, researchers have modified its structure under the premise of not damaging the basic scaffold structure. In this review, we comprehensively discuss and summarize the potential anti-tumor mechanisms and the progress of structural modifications of β-elemene.

Chemical Characteristics and Anticancer Activity of Essential Oil from Arnica Montana L. Rhizomes and Roots

Arnica montana L. is a medicinal plant with diverse biological activities commonly used in pharmacy and cosmetics. The attributes of A. montana are mainly related to the concentration and chemical composition of essential oils (EOs). Therefore, the objective of this study was to characterize the chemical composition of EOs derived from A. montana rhizomes and roots taking into account the age of the plants and to investigate the effect of the analyzed EOs on induction of apoptosis, necrosis, and autophagy in human glioblastoma multiforme T98G and anaplastic astrocytoma MOGGCCM cell lines. Rhizomes and roots of mountain arnica were harvested at the end of the third and fourth vegetation periods. The chemical composition of essential oils was determined with the GC–MS technique. Among the 37 components of the essential oil of A. montana, 2,5-dimethoxy-p-cymene (46.47%–60.31%), 2,6-diisopropylanisole (14.48%–23.10%), thymol methyl ether (5.31%–17.79%), p-methoxyheptanophenone (5.07%–9.65%), and α-isocomene (0.68%–2.87%), were detected in the rhizomes and roots of the three-year-old plants and in the rhizomes and roots of the four-year-old plants. The plant part (rhizome, root) and plant age can be determinants of the essential oil composition and, consequently, their biological activity. The induction of apoptosis (but not autophagy nor necrosis) at a level of 28.5%–32.3% is a promising result, for which 2,5-dimethoxy-p-cymene, 2,6-diisopropylanisole, thymol methyl ether, and p-methoxyheptanophenone are probably mainly responsible. The present study is the first report on the anticancer activities of essential oils from A. montana rhizomes and roots.

Essential Oil from Arnica Montana L. Achenes: Chemical Characteristics and Anticancer Activity

Mountain arnica Arnica montana L. is a source of several metabolite classes with diverse biological activities. The chemical composition of essential oil and its major volatile components in arnica may vary depending on the geographical region, environmental factors, and plant organ. The objective of this study was to characterize the chemical composition of essential oil derived from A. montana achenes and to investigate its effect on induction of apoptosis and autophagy in human anaplastic astrocytoma MOGGCCM and glioblastoma multiforme T98G cell lines. The chemical composition of essential oil extracted from the achenes was examined with the use of Gas Chromatography–Mass Spectrometry GC-MS. Only 16 components of the essential oil obtained from the achenes of 3-year-old plants and 18 components in the essential oil obtained from the achenes of 4-year-old plants constituted ca. 94.14% and 96.38% of the total EO content, respectively. The main components in the EO from the arnica achenes were 2,5-dimethoxy-p-cymene (39.54 and 44.65%), cumene (13.24 and 10.71%), thymol methyl ether (8.66 and 8.63%), 2,6-diisopropylanisole (8.55 and 8.41%), decanal (7.31 and 6.28%), and 1,2,2,3-tetramethylcyclopent-3-enol (4.33 and 2.94%) in the 3- and 4-year-old plants, respectively. The essential oils were found to exert an anticancer effect by induction of cell death in anaplastic astrocytoma and glioblastoma multiforme cells. The induction of apoptosis at a level of 25.7–32.7% facilitates the use of this secondary metabolite in further studies focused on the development of glioma therapy in the future. Probably, this component plays a key role in the anticancer activity against the MOGGCCM and T98G cell lines. The present study is the first report on the composition and anticancer activities of essential oil from A. montana achenes, and further studies are required to explore its potential for future medicinal purposes.

The Use of ß-Elemene to Enhance Radio Sensitization of A375 Human Melanoma Cells

Objective

Melanoma is the most malignant and severe type of skin cancer. It is a tumor with a high risk of metastasis and resistant to conventional treatment methods (surgery, radiotherapy, and chemotherapy). β-elemene is the most active constituent of Curcuma wenyujin which is a non-cytotoxic antitumor drug, proved to be effective in different types of cancers. The study aimed to investigate the therapeutic effects of β-elemene in combination with radiotherapy on A375 human melanoma.

Materials and Methods

In this experimental study, human melanoma cells were grown in the monolayer culture model. The procedure of the treatment was performed by the addition of different concentrations of β-elemene to the cells. Then, the cells were exposed to 2 and 4 Gy X-ray in different incubation times (24, 48, and 72 hours). The MTT assay was used for the determination of the cell viability. To study the rate of apoptosis response to treatments, the Annexin V/PI assay was carried out.

Results

The results of the MTT assay showed β-elemene reduced the cell proliferation in dose- and time-dependent manners in cells exposed to radiation. Flow cytometry analysis indicated that β-elemene was effective in the induction of apoptosis. Furthermore, the combination treatment with radiation remarkably decreased the cells proliferation ability and also enhanced apoptosis. For example, cell viability in a group exposed to 40 µg/ml of β-elemene was 80%, but combination treatment with 6 MV X beam at a dose of 2 Gy reduced the viability to 61%.

Conclusion

Our results showed that β-elemene reduced the proliferation of human melanoma cancer cell through apoptosis. Also, the results demonstrated that the radio sensitivity of A375 cell line was significantly enhanced by β-elemene. The findings of this study indicated the efficiency of β-elemene in treating melanoma cells and the necessity for further research in this field.

Molecular targets of β-elemene, a herbal extract used in traditional Chinese medicine, and its potential role in cancer therapy: A review

β-Elemene is a sesquiterpene compound extracted from the herb Curcuma Rhizoma and is used in traditional Chinese medicine (TCM) to treat several types of cancer, with no reported severe adverse effects. Recent studies, using in vitro and in vivo studies combined with molecular methods, have shown that β-elemene can inhibit cell proliferation, arrest the cell cycle, and induce cell apoptosis. Recent studies have identified the molecular targets of β-elemene that may have a role in cancer therapy. This review aims to discuss the anticancer potential of β-elemene through its actions on several molecular targets including kinase enzymes, transcription factors, growth factors and their receptors, and proteins. β-Elemene also regulates the expression of several key molecules that are involved in tumor angiogenesis and metastasis including vascular endothelial growth factor (VEGF), matrix metalloproteinases (MMPs), E-cadherin, N-cadherin, and vimentin. Also, β-elemene has been shown to have regulatory effects on the immune response and increases the sensitivity of cancer cells to chemoradiotherapy and has shown effects on multidrug resistance (MDR) in malignancy. Recent studies have shown that β-elemene can induce autophagy, which prevents cancer cells from undergoing apoptosis. Therefore, the molecular mechanisms for the treatment effects on cancer of the herbal extract, β-elemene, which has been used for centuries in traditional Chinese medicine, are now being studied and identified.

Antitumor Mechanisms of Curcumae Rhizoma Based on Network Pharmacology

Curcumae Rhizoma, a traditional Chinese medication, is commonly used in both traditional treatment and modern clinical care. Its anticancer effects have attracted a great deal of attention, but the mechanisms of action remain obscure. In this study, we screened for the active compounds of Curcumae Rhizoma using a drug-likeness approach. Candidate protein targets with functions related to cancer were predicted by reverse docking and then checked by manual search of the PubMed database. Potential target genes were uploaded to the GeneMANIA server and DAVID 6.8 database for analysis. Finally, compound-target, target-pathway, and compound-target-pathway networks were constructed using Cytoscape 3.3. The results revealed that the anticancer activity of Curcumae Rhizoma potentially involves 13 active compounds, 33 potential targets, and 31 signaling pathways, thus constituting a “multiple compounds, multiple targets, and multiple pathways” network corresponding to the concept of systematic actions in TCM. These findings provide an overview of the anticancer action of Curcumae Rhizoma from a network perspective, as well as setting an example for future studies of other materials used in TCM.

Therapeutic effects of β-elemene via attenuation of the Wnt/β-catenin signaling pathway in cervical cancer cells

Concurrent radio chemotherapy treatment prolongs the survival rate of patients with advanced cervical cancer; however, it has adverse side-effects. β-elemene, an active component of the traditional Chinese medicinal herb Curcuma zedoaria, is a promising alternative therapeutic drug for the treatment of advanced cervical cancer. The aim of the present study was to investigate the antitumor effects of β-elemene in human cervical cancer SiHa cells and to determine its underlying therapeutic molecular mechanisms. Cell viability, cell cycle progression and apoptosis were detected using an MTT assay and flow cytometry analysis. Furthermore, the levels of cell migration and cell invasion were investigated using Transwell and wound healing assays. The expression levels of Cyclin-dependent kinase inhibitor 2B (P15), Cyclin D1, cellular tumor antigen p53, apoptosis regulator Bcl-2 (Bcl-2), apoptosis regulator BAX (Bax), 72 kDa type IV collagenase (MMP-2), matrix metalloproteinase-9 (MMP-9), β-catenin, transcription factor 7 (TCF7), and Myc proto-oncogene protein (c-Myc) were analyzed via western blotting. The results revealed that β-elemene inhibited the proliferation of SiHa cells in a dose and time-dependent manner. Administration of β-elemene induced G1 phase cell-cycle arrest, as demonstrated by the upregulation of P15 expression and the downregulation of Cyclin D1 expression. Furthermore, the present study revealed that β-elemene induced apoptosis in SiHa cells by enhancing the expression of p53 and Bax, and suppressing the expression of Bcl-2. In addition, treatment with β-elemene inhibited cell migration and invasion via downregulation of MMP-2 and MMP-9 expression levels. Western blotting demonstrated that β-elemene reduced the expression levels of β-catenin and its downstream target molecule TCF7, thus resulting in reduced levels of their target proteins, including c-Myc, Cyclin D1, Bax and MMP-2 in cervical cancer cells. The results of the present study suggested that β-elemene may inhibit cell proliferation and invasion, in addition to inducing apoptosis, via attenuation of the Wnt/β-catenin signaling pathway in cervical cancer cells.

Chemical constituents and biological research on plants in the genus Curcuma

Curcuma, a valuable genus in the family Zingiberaceae, includes approximately 110 species. These plants are native to Southeast Asia and are extensively cultivated in India, China, Sri Lanka, Indonesia, Peru, Australia, and the West Indies. The plants have long been used in folk medicine to treat stomach ailments, stimulate digestion, and protect the digestive organs, including the intestines, stomach, and liver. In recent years, substantial progress has been achieved in investigations regarding the chemical and pharmacological properties, as well as in clinical trials of certain Curcuma species. This review comprehensively summarizes the current knowledge on the chemistry and briefly discusses the biological activities of Curcuma species. A total of 720 compounds, including 102 diphenylalkanoids, 19 phenylpropene derivatives, 529 terpenoids, 15 flavonoids, 7 steroids, 3 alkaloids, and 44 compounds of other types isolated or identified from 32 species, have been phytochemically investigated. The biological activities of plant extracts and pure compounds are classified into 15 groups in detail, with emphasis on anti-inflammatory and antitumor activities.

β-Elemene treatment of glioblastoma: a single-center retrospective study

Glioblastoma (GBM) is the most common primary malignancy in the central nervous system. In this study, we investigated the therapeutic effects of β-elemene (ELE) treatment in patients with newly diagnosed GBM who received concomitant chemoradiotherapy and adjuvant chemotherapy with temozolomide. Our results indicated that compared with control, patients who received ELE showed significantly longer median progression-free survival (PFS) (8 months vs 11 months; P<0.001) and overall survival (OS) (18 months vs 21 months; P<0.001). Despite the O-6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status, ELE treatment could significantly prolong the PFS (P=0.038) and OS (P=0.016). In multivariate analysis, ELE was a significant prognostic factor for PFS (hazard ratio [HR], 0.34; 95% confidence interval [95% CI]: 0.15–0.62; P=0.011) and OS (HR, 0.31; 95% CI: 0.14–0.69; P=0.006). Furthermore, ELE could significantly reduce the hematologic toxicities induced by chemoradiotherapy. In conclusion, ELE might provide a survival benefit in patients with GBM. Further study for verification might be needed.

β-Elemene Selectively Inhibits the Proliferation of Glioma Stem-Like Cells Through the Downregulation of Notch1

Glioma is the most frequent primary central nervous system tumor. Although the current first-line medicine, temozolomide (TMZ), promotes patient survival, drug resistance develops easily. Thus, it is important to investigate novel therapeutic reagents to solidify the treatment effect. β-Elemene (bELE) is a compound from a Chinese herb whose anticancer effect has been shown in various types of cancer. However, its role in the inhibition of glioma stem-like cells (GSLCs) has not yet been reported. We studied both the in vitro and the in vivo inhibitory effect of bELE and TMZ in GSLCs and parental cells and their combined effects. The molecular mechanisms were also investigated. We also optimized the delivery methods of bELE. We found that bELE selectively inhibits the proliferation and sphere formation of GSLCs, other than parental glioma cells, and TMZ exerts its effects on parental cells instead of GSLCs. The in vivo data confirmed that the combination of bELE and TMZ worked better in the xenografts of GSLCs, mimicking the situation of tumorigenesis of human cancer. Notch1 was downregulated with bELE treatment. Our data also demonstrated that the continuous administration of bELE produces an ideal effect to control tumor progression. Our findings have demonstrated, for the first time, that bELE could compensate for TMZ to kill both GSLCs and nonstem-like cancer cells, probably improving the prognosis of glioma patients tremendously. Notch1 might be a downstream target of bELE. Therefore, our data shed light on improving the outcomes of glioma patients by combining bELE and TMZ. Stem Cells Translational Medicine 2017;6:830-839.

Demethylation effects of elemene on the GSTP1 gene in HCC cell line QGY7703

The present study aimed to investigate elemene's effects on cell proliferation, apoptosis, and the cell cycle in the hepatocellular carcinoma (HCC) cell line, QYG7703, and to investigate GSTP1 gene methylation change in QGY7703 cells after being treated with elemene to explore whether elemene reversed the abnormal GSTP1 gene methylation. QGY7703 cells were treated with different elemene concentrations. Cell proliferation was measured with MTT assay, cell apoptosis and cell cycle were analyzed by flow cytometry, and GSTP1 gene methylation was analyzed by methlation-specific polymerase chain reaction. The cells' apoptotic rate increased dose-dependently with elemene concentration, and the difference was statistically significant (P<0.05). Elemene treatment arrested the cells in S phase, and thus the percentage of cells in G1 phase decreased while the cells in S phase increased dose-dependently, and the difference was statistically significant compared to the control group (P<0.05). All QGY7703 cells were identified to contain GSTP1 gene methylation before being treated with elemene and the methylation state decreased after treatment. In the present study, elemene induced cell apoptosis, inhibited the cell cycle, and reversed GSTP1 gene methylation in QGY7703 cells.

Two Traditional Chinese Medicines Curcumae Radix and Curcumae Rhizoma: An Ethnopharmacology, Phytochemistry, and Pharmacology Review

Curcumae Rhizoma, known as Ezhu (Chinese: ), and Curcumae Radix, known as Yujin (Chinese: ), are different plant parts coming from three same species according to China Pharmacopoeia. Actually, they are used in different ways in TCM clinical treatment. Curcumae Rhizoma is mainly used as antitumor drug, while Curcumae Radix has been used as antidepressant and cholagogue. Curcumae Rhizoma and Curcumae Radix are confused in variety and source, even in clinical trials by some nonprofessional workers. So it is important for us to make them clear. This review is aimed at summarizing the ethnopharmacology, phytochemical, and pharmacological differences between Curcumae Radix and Curcumae Rhizoma by SciFinder, CNKI, and so on, to use them exactly and clearly. Further studies on Curcumae Rhizoma and Curcumae Radix can lead to the development of new drugs and therapeutics for various diseases on the basis of the TCM theory.

Reversion of malignant phenotypes of human glioblastoma cells by β-elemene through β-catenin-mediated regulation of stemness-, differentiation- and epithelial-to-mesenchymal transition-related molecules

Background

Glioblastoma is the most common and lethal type of primary brain tumor. β-Elemene, a natural plant drug extracted from Curcuma wenyujin, has shown strong anti-tumor effects in various tumors with low toxicity. However, the effects of β-elemene on malignant phenotypes of human glioblastoma cells remain to be elucidated. Here we evaluated the effects of β-elemene on cell proliferation, survival, stemness, differentiation and the epithelial-to-mesenchymal transition (EMT) in vitro and in vivo, and investigated the mechanisms underlying these effects.

Methods

Human primary and U87 glioblastoma cells were treated with β-elemene, cell viability was measured using a cell counting kit-8 assay, and treated cells were evaluated by flow cytometry. Western blot analysis was carried out to determine the expression levels of stemness markers, differentiation-related molecules and EMT-related effectors. Transwell assays were performed to further determine EMT of glioblastoma cells. To evaluate the effect of β-elemene on glioblastoma in vivo, we subcutaneously injected glioblastoma cells into the flank of nude mice and then intraperitoneally injected NaCl or β-elemene. The tumor xenograft volumes were measured every 3 days and the expression of stemness-, differentiation- and EMT-related effectors was determined by Western blot assays in xenografts.

Results

β-Elemene inhibited proliferation, promoted apoptosis, impaired invasiveness in glioblastoma cells and suppressed the growth of animal xenografts. The expression levels of the stemness markers CD133 and ATP-binding cassette subfamily G member 2 as well as the mesenchymal markers N-cadherin and β-catenin were significantly downregulated, whereas the expression levels of the differentiation-related effectors glial fibrillary acidic protein, Notch1, and sonic hedgehog as well as the epithelial marker E-cadherin were upregulated by β-elemene in vitro and in vivo. Interestingly, the expression of vimentin was increased by β-elemene in vitro; this result was opposite that for the in vivo procedure. Inhibiting β-catenin enhanced the anti-proliferative, EMT-inhibitory and specific marker expression-regulatory effects of β-elemene.

Conclusions

β-Elemene reversed malignant phenotypes of human glioblastoma cells through β-catenin-involved regulation of stemness-, differentiation- and EMT-related molecules. β-Elemene represents a potentially valuable agent for glioblastoma therapy.

Hypoxia-inducible factor-1 and associated upstream and downstream proteins in the pathophysiology and management of glioblastoma

Glioblastoma multiforme (GBM) is a highly aggressive brain tumor with an exceptionally poor patient outcome despite aggressive therapy including surgery, radiation, and chemotherapy. This aggressive phenotype may be associated with intratumoral hypoxia, which probably plays a key role in GBM tumor growth, development, and angiogenesis. A key regulator of cellular response to hypoxia is the protein hypoxia-inducible factor–1 (HIF-1). An examination of upstream hypoxic and nonhypoxic regulation of HIF-1 as well as a review of the downstream HIF-1– regulated proteins may provide further insight into the role of this transcription factor in GBM pathophysiology. Recent insights into upstream regulators that intimately interact with HIF-1 could provide potential therapeutic targets for treatment of this tumor. The same is potentially true for HIF-1–mediated pathways of glycolysis-, angiogenesis-, and invasion-promoting proteins. Thus, an understanding of the relationship between HIF-1, its upstream protein regulators, and its downstream transcribed genes in GBM pathogenesis could provide future treatment options for the care of patients with these tumors.

β-elemene enhances both radiosensitivity and chemosensitivity of glioblastoma cells through the inhibition of the ATM signaling pathway

Glioblastoma multiforme (GBM), a tumor associated with poor prognosis, is known to be resistant to radiotherapy and alkylating agents such as temozolomide (TMZ). β-elemene, a monomer found in Chinese traditional herbs extracted from Curcuma wenyujin, is currently being used as an antitumor drug for different types of tumors including GBM. In the present study, we investigated the roles of β-elemene in the radiosensitivity and chemosensitivity of GBM cells. Human GBM cell lines U87-MG, T98G, U251, LN229 and rat C6 cells were treated with β-elemene combined with radiation or TMZ. We used MTT and colony forming assays to evaluate the proliferation and survival of the cells, and the comet assay to observe DNA damage. Expression of proteins was analyzed by immunoblotting. In the present study, we found that β-elemene inhibited the proliferation and survival of different GBM cell lines when combined with radiotherapy or TMZ via inhibition of DNA damage repair. Treatment of GBM cells with β-elemene decreased the phosphorylation of ataxia telangiectasia mutated (ATM), AKT and ERK following radiotherapy or chemotherapy. These results revealed that β-elemene could significantly increase the radiosensitivity and chemosensitivity of GBM. β-elemene may be used as a potential drug in combination with the radiotherapy and chemotherapy of GBM.

β-Elemene inhibits proliferation through crosstalk between glia maturation factor β and extracellular signal‑regulated kinase 1/2 and impairs drug resistance to temozolomide in glioblastoma cells

β-elemene, a plant-derived drug extracted from Curcuma wenyujin, has demonstrated marked antiproliferative effects on glioblastoma, while toxicity remains low. However, the underlying molecular mechanisms of the antitumor activity of β-elemene remain to be elucidated. Previously, it was identified that the glia maturation factor β (GMFβ)/mitogen-activated protein kinase kinase (MAPK) 3/6/p38 pathway participates in the antiproliferative activity of β-elemene on glioblastoma. In the present study, in order to illustrate the association of GMFβ and the extracellular signal-regulated kinase 1/2 (ERK1/2) pathway, U87 and U251 cells were treated with β-elemene at various doses and for different durations, and the expression of phosphorylated ERK1/2 (p-ERK1/2), ERK1/2, B-cell lymphoma 2 (Bcl-2), Bcl2-associated X and survivin was examined by western blot analysis. Following treatment with β-elemene and the ERK1/2 inhibitor PD98059, U87 cell viability was evaluated using a Cell Counting Kit-8 (CCK-8) assay, and the expression levels of Bcl-2 and survivin were examined by western blot analysis. GMFβ was then downregulated by RNA interference in β-elemene-treated U87 cells, and the effect of this on the expression of ERK1/2 and p-ERK1/2 was determined by western blot analysis. Finally, the chemosensitisation of U87 cells to temozolomide (TMZ) through β-elemene was examined using the CCK-8 assay. The results demonstrated that β-elemene inhibited the proliferation of U87 glioblastoma cells through the GMFβ‑dependent inactivation of the ERK1/2-Bcl-2/survivin pathway. Furthermore, inhibition of ERK1/2 by PD98059 enhanced the antitumor effect of β-elemene and impaired the expression levels of Bcl-2 and survivin. β-elemene also increased the sensitivity of U87 glioblastoma cells to the chemotherapeutic TMZ, which was synergistically enhanced by PD98059. In conclusion, these results suggested that GMFβ-dependent inactivation of the ERK1/2-Bcl-2/survivin pathway mediated the antiproliferative effect of β-elemene on glioblastoma. Therefore, β-elemene is a promising chemosensitizer or adjuvant therapeutic for TMZ against glioblastoma brain tumors.

β-elemene inhibits stemness, promotes differentiation and impairs chemoresistance to temozolomide in glioblastoma stem-like cells

Accumulating evidence indicates that glioblastoma stem-like cells (GSCs) are key factors in tumour development, recurrence and chemoresistance. The impairment of stemness and the enhancement of differentiation contributes to the weakening of radiation and chemotherapy resistance of GSCs. We previously found that β-elemene was an effective anti-glioblastoma agent and chemosensitizer. In this study, we examined the distribution of CD133(+) cells in human glioblastoma tissues by immunohistochemistry. Following treatment with β-elemene, the formation of GSC spheres was investigated by manual counting, the proliferation of GSCs was measured with a Cell Counting Kit-8 (CCK-8) assay, and the dispersion of GSC spheres was observed with an inverted microscope. GSC spheres were treated with β-elemene, and the expression levels of CD133, ATP-binding cassette subfamily G member 2 (ABCG2) and glial fibrillary acidic protein (GFAP) were examined by western blotting. After treatment with β-elemene, the volumes and weights of GSC xenografts were measured, and the expression of CD133, ABCG2 and GFAP was evaluated through immunohistochemistry analysis. After treatment with β-elemene and temozolomide (TMZ), GSC viability was examined by the CCK-8 assay, and the volumes and weights of xenografts were measured. We found that CD133(+) cells were assembled in some vascular walls and also sparsely distributed in other parts of glioblastoma tissues. β-elemene decreased the formation of GSC spheres, dispersed GSC spheres and inhibited the proliferation of GSCs in vitro and in vivo. In the GSC spheres and xenografts treated with β-elemene, the expression of CD133 and ABCG2 was significantly downregulated, and the expression of GFAP increased. Furthermore, the sensitivity of GSCs to TMZ was enhanced in vitro and in vivo. These results suggest that β-elemene impaired the stemness of GSC spheres, promoted their differentiation and sensitized GSCs to TMZ. β-elemene will hopefully become a valuable agent to enhance the effects of radiotherapy and chemotherapy.

Isolation of jasmonate-induced sesquiterpene synthase of rice: product of which has an antifungal activity against Magnaporthe oryzae

Rice is one of the most important crops worldwide, and it is a model for molecular studies of monocotyledonous species, particularly for understanding the molecular mechanisms of plant disease resistance. Jasmonic acid (JA) is an important plant hormone involved in rice-pathogen interactions. In addition, JA-induced volatiles are known to be involved in the rice defense system regulated by JA signaling. In this study, we isolated a JA-induced terpene synthase from rice, and found that it produces two sesquiterpenes; β-elemene and β-bisabolene. Furthermore, β-elemene exhibited significant antifungal activity against Magnaporthe oryzae; however it did not exhibited any antibacterial activity against Xanthomonas oryzae pv. oryzae. JA-induced accumulation of β-elemene was regulated by OsJAZ8, a rice jasmonate ZIM-domain (JAZ) protein that is involved in the JA signaling pathway, suggesting that β-elemene plays an important role in JA-induced resistance, and that it functions as an antifungal compound in rice.

Curcumin-free turmeric exhibits anti-inflammatory and anticancer activities: Identification of novel components of turmeric

Turmeric, a dried powder derived from the rhizome of Curcuma longa, has been used for centuries in certain parts of the world and has been linked to numerous biological activities including antioxidant, anti-inflammatory, anticancer, antigrowth, anti-arthritic, anti-atherosclerotic, antidepressant, anti-aging, antidiabetic, antimicrobial, wound healing, and memory-enhancing activities. One component of turmeric is curcumin, which has been extensively studied, as indicated by more than 5600 citations, most of which have appeared within the past decade. Recent research has identified numerous chemical entities from turmeric other than curcumin. It is unclear whether all of the activities ascribed to turmeric are due to curcumin or whether other compounds in turmeric can manifest these activities uniquely, additively, or synergistically with curcumin. However, studies have indicated that turmeric oil, present in turmeric, can enhance the bioavailability of curcumin. Studies over the past decade have indicated that curcumin-free turmeric (CFT) components possess numerous biological activities including anti-inflammatory, anticancer, and antidiabetic activities. Elemene derived from turmeric is approved in China for the treatment of cancer. The current review focuses on the anticancer and anti-inflammatory activities exhibited by CFT and by some individual components of turmeric, including turmerin, turmerone, elemene, furanodiene, curdione, bisacurone, cyclocurcumin, calebin A, and germacrone.

Beta-elemene blocks epithelial-mesenchymal transition in human breast cancer cell line MCF-7 through Smad3-mediated down-regulation of nuclear transcription factors

Epithelial-mesenchymal transition (EMT) is the first step required for breast cancer to initiate metastasis. However, the potential of drugs to block and reverse the EMT process are not well explored. In the present study, we investigated the inhibitory effect of beta-elemene (ELE), an active component of a natural plant-derived anti-neoplastic agent in an established EMT model mediated by transforming growth factor-beta1 (TGF-β1). We found that ELE (40 µg/ml ) blocked the TGF-β1-induced phenotypic transition in the human breast cancer cell line MCF-7. ELE was able to inhibit TGF-β1-mediated upregulation of mRNA and protein expression of nuclear transcription factors (SNAI1, SNAI2, TWIST and SIP1), potentially through decreasing the expression and phosphorylation of Smad3, a central protein mediating the TGF-β1 signalling pathway. These findings suggest a potential therapeutic benefit of ELE in treating basal-like breast cancer.

Antiproliferative and apoptotic effects of β-elemene on human hepatoma HepG2 cells

BACKGROUND

β-elemene, a natural sesquiterpene extracted from the essential oils of Curcuma aromatica Salisb, has been shown to be effective against a wide range of tumors. In this study, the antitumor effect of β-elemene on a human hepatoma cell line, HepG2, and the mechanism involved have been investigated.

METHODS

MTT assay was used to determine the growth inhibition of hepatoma HepG2 cells in vitro. Apoptosis of HepG2 cells were demonstrated by fluorescence microscope with Hoechst 33258 staining and flow cytometry with Annexin V-FITC/PI double staining. Flow cytometry was performed to analyze the cell cycle distribution of HepG2 cells. The mRNA and protein expression of Fas and FasL were measured by RT-PCR and Western blot analysis.

RESULTS

MTT results showed that β-elemene could inhibit the proliferation of HepG2 cells in a time- and dose- dependent manner. Our results showed β-elemene had positive effect on apoptosis through fluorescence microscope and flow cytometry assay. Furthermore, β-elemene could induce the cell cycle arrest of the HepG2 cells in the G2/M phase. Fas and FasL expression were obviously increased after β-elemene treatment in both mRNA and protein level.

CONCLUSION

The present study indicates that β-elemene can effectively inhibit proliferation and induce apoptosis in hepatoma HepG2 cells, and the apoptosis induction is related with up-regulating of Fas/FasL expression.

Aldehyde dehydrogenase and HSP90 co-localize in human glioblastoma biopsy cells

The concept of a stem cell subpopulation as understood from normal epithelial tissue or bone marrow function has been extended to our understanding of cancer tissue and is now the target of treatment efforts specifically directed to this subpopulation. In glioblastoma, as well as in other cancers, increased expression of aldehyde dehydrogenase (ALDH) has been found localized within a minority sub-population of tumor cells which demonstrate stem cell properties. A separate body of research associated increased expression of heat-shock protein-90 (HSP90) with stem cell attributes. We present here results from our initial immunohistochemistry study of human glioblastoma biopsy tissue where both ALDH and HSP90 tended to be co-expressed in high amounts in the same minority of cells. Since 12% of all cells in the six biopsies studied were ALDH positive and 17% were HSP90 positive, by chance alone 2% would have been expected to be positive for both. In fact 7% of all cells simultaneously expressed both markers-a significant difference (p = 0.037). That two previously identified proteins associated with stem cell attributes tend to be co-expressed in the same individual glioblastoma cells might have clinical utility. Disulfiram, used to treat alcoholism for half-a century now, is a potent ALDH inhibitor and the old anti-viral drug ritonavir inhibits HSP90. These should be explored for the potential to retard aspects of glioblastoma stem cells' function subserved by ALDH and HSP90.

Chemistry and biological activities of terpenoids from copaiba (Copaifera spp.) oleoresins

Copaiba oleoresins are exuded from the trunks of trees of the Copaifera species (Leguminosae-Caesalpinoideae). This oleoresin is a solution of diterpenoids, especially, mono- and di-acids, solubilized by sesquiterpene hydrocarbons. The sesquiterpenes and diterpenes (labdane, clerodane and kaurane skeletons) are different for each Copaifera species and have been linked to several reported biological activities, ranging from anti-tumoral to embriotoxic effects. This review presents all the substances already described in this oleoresin, together with structures and activities of its main terpenoids.