Antimetastatic effects of Celastrus orbiculatus on human gastric adenocarcinoma by inhibiting epithelial-mesenchymal transition and NF-κB/snail signaling pathway

A Review of Herbal Resources Inducing Anti-Liver Metastasis Effects in Gastrointestinal Tumors via Modulation of Tumor Microenvironments in Animal Models

Liver metastases remain a major obstacle for the management of all types of tumors arising from digestive organs, and the tumor microenvironment has been regarded as an important factor in metastasis. To discover herbal candidates inhibiting the liver metastasis of tumors originating from the digestive system via the modulation of the tumor microenvironment and liver environment, we searched three representative public databases and conducted a systematic review. A total of 21 studies that employed experimental models for pancreatic (9), colon (8), and stomach cancers (4) were selected. The herbal agents included single-herb extracts (5), single compounds (12), and multiherbal decoctions (4). Curcuma longa Linn was most frequently studied for its anti-colon-liver metastatic effects, and its possible mechanisms involved the modulation of tumor microenvironment components such as vascular endothelial cells and immunity in both tumor tissues and circulating cells. The list of herbal agents and their mechanisms produced in this study is helpful for the development of anti-liver metastasis drugs in the future.

The anti-tumor effects of Celastrus orbiculatus Thunb. and its monomer composition: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Celastrus orbiculatus Thunb. has been included in "The Plant List" (http://www. theplantlist.org) and is the most widely researched species in its genus. It is called Nanshe Teng in China. Celastrus orbiculatus Thunb. is a plant of Euonymus and it's medicinal part is the vine and stem. It is also called Alias Dragon grass, Yellow Yine, etc. It has good anti-tumor, anti-inflammatory and other effects. More and more studies have shown that Celastrus orbiculatus Thunb. has a significant therapeutic effect on a variety of malignant tumors. The research on Celastrus orbiculatus Thunb. has a good application prospect for the development of anti-tumor drugs. However, no systematic reports on Celastrus orbiculatus Thunb. have been published before.

AIM OF THE REVIEW

This paper summarizes the metabolic products for anti-tumor and the mechanism for anti-tumor of Celastrus orbiculatus Thunb. to provide reference for further development and research.

MATERIALS AND METHODS

The relevant information on Celastrus orbiculatus Thunb. was collected from the scientific databases including PubMed, CNKI, ScienceDirect, Wiley, Springer, Web of Science, Google Scholar, Baidu Scholar, Pharmacopoeia of the People's Republic of China and Flora Republicae Popularis Sinicae, etc. RESULTS: At present, more than 200 compounds have been identified from Celastrus orbiculatus Thunb., including terpenoids, flavonoids, phenylpropanoids, polyketides and benzene derivatives, etc. Pharmacological studies have shown that Celastrus orbiculatus Thunb. has a variety effects of inhibiting tumor cell proliferation, inducing tumor cell apoptosis, inhibiting tumor cells invasion, metastasis and angiogenesis, reversing multi-drug resistance, and also collaborativing Micro RNA to inhibit tumor growth, etc. It has a significant effect on gastric cancer, liver cancer, lung cancer, etc. The extracts of Celastrus orbiculatus Thunb. have been widely used in experiments, and the toxic and side effects are small.

CONCLUSIONS

Celastrus orbiculatus Thunb. is rich in chemical constituents, diverse in pharmacological activities and abundant in resources, which is widely used in clinics from traditional to modern. However, there is no systematic report on the chemical compounds and anti-tumor effects of Celastrus orbiculatus Thunb. We organize and summarize it to provide reference for further development and research.

Tumour Necrosis Factor Alpha (TNF-α) and Oral Squamous Cell Carcinoma

Uncovering the inflammatory mechanisms underpinning initiation, progression, and promotion of oral squamous cell carcinoma (OSCC) development is fundamental to the rational pursuit of targeted therapeutics. Here we present a review of the current knowledge of the role of TNF-α in the aetiology, pathogenesis, and potential therapies with regards to OSCC. TNF-α is worthy of particular attention in OSCC, with its presence demonstrated to enhance cell proliferation and its downregulation demonstrated to inhibit proliferation and migration in other carcinomas in both in vitro and in vivo models and oral cancer patients. Increased TNF-α in the OSCC tumour microenvironment has been demonstrated to favour invasion through promotion of firstly the pro-inflammatory, pro-invasive phenotypes of OSCC cells and secondly its paracrine mechanism mediating recruitment and activation of inflammatory cells. Polymorphisms affecting the gene expression of TNF-α have been strongly associated with an increased risk for oral squamous cell carcinoma. A number of studies have considered TNF-α within biofluids, including saliva and serum, as a potential biomarker for the early detection of OSCC, as well as its staging, differentiation, and prognosis. The broad and multifaceted role that TNF-α plays in many inflammatory states presents an obvious confounder, particularly with demonstrated increased TNF-α levels in common oral disease states. Lastly, biologic agents targeting TNF-α are currently in clinical use for immune-mediated inflammatory rheumatological and gastrointestinal diseases. There is the potential that these biological agents might have an adjunctive role in OSCC prevention and treatment.

Triptonoterpene, a Natural Product from Celastrus orbiculatus Thunb, Has Biological Activity against the Metastasis of Gastric Cancer Cells

Cancer is one of the greatest threats to human health. Gastric cancer (GC) is the fifth most common malignant tumor in the world. Invasion and metastasis are the major difficulties in the treatment of GC. Herbal medicines and their extracts have a lengthy history of being used to treat tumors in China. The anti-tumoral effects of the natural products derived from herbs have received a great deal of attention. Our previous studies have shown that the traditional Chinese herb Celastrus orbiculatus Thunb extract (COE) can inhibit the invasion and metastasis of GC cells, but the specific anti-cancer components of COE are still unclear. Dozens of natural products from COE have been isolated and identified by HPLC spectroscopy in our previous experiments. Triptonoterpene is one of the active ingredients in COE. In this study, we focused on revealing whether Triptonoterpene has an excellent anti-GC effect and can be used as an effective component of Celastrus orbiculatus Thunb in the treatment of tumors. We first observed that Triptonoterpene reduces GC cell proliferation through CCK-8 assays and colony formation experiments. The cell adhesion assays have shown that Triptonoterpene inhibits adhesion between cells and the cell matrix during tumor invasion. In addition, the cell migration assay has shown that Triptonoterpene inhibits the invasion and migration of GC cells. The high-connotation cell dynamic tracking experiment has also shown the same results. The effects of Triptonoterpene on epidermal mesenchymal transition (EMT)-related and matrix metalloproteinases (MMPs)-related proteins in gastric cancer cells were detected by Western blots. We found that Triptonoterpene could significantly inhibit the changes in EMT-related and invasion and metastasis-related proteins. Altogether, these results suggest that Triptonoterpene is capable of inhibiting the migration and invasion of GC cells. Triptonoterpene, as a natural product from Celastrus orbiculatus Thunb, has significant anti-gastric cancer effects, and is likely to be one of the major equivalent components of Celastrus orbiculatus Thunb.

Celastrus orbiculatus Extract Reduces Stemness of Gastric Cancer Stem Cells by Targeting PDCD4 and EIF3H

BACKGROUND

Celastrus orbiculatus ethyl acetate extract (COE) has shown a strong anti-gastric cancer effect, but the understanding of its mechanism is still lacking. The results of previous studies indicated that COE may be able to inhibit the stemness of gastric cancer stem cells (GCSCs) by regulating PDCD4 and EIF3H expression.

AIMS

To explore if COE could inhibit the stemness of GCSCs by regulating PDCD4 and EIF3H expression in vitro and in vivo.

PROCEDURE

The GCSCs model was established by stem cell-conditioned culture. Spheroid formation and flow cytometry assays were used to detect the effect of COE on the spheroid formation ability of GCSCs and the percentage of CD44⁺/CD24⁺ and ALDH⁺ cell subpopulations. Western blot analysis was applied to measure the expression of GCSCs biomarkers (Nanog, Oct-4, and SOX-2), PDCD4, and EIF3H in GCSCs treated with COE; and RT-PCR was performed to investigate the effect of COE on PDCD4 mRNA expression in GCSCs. An in vivo tumorigenicity experiment was also conducted to evaluate the effect of COE on tumor-initiating ability of GCSCs in vivo; and the expression of PDCD4 and EIF3H in xenograft tissues was examined by immunohistochemistry (IHC) staining.

RESULTS

After culture in stem cell-conditioned medium, SGC7901 cells manifested significantly enhanced spheroid formation ability, upregulated Nanog, Oct-4, and SOX-2 expression and increased percentages of CD44⁺/CD24⁺ and ALDH⁺ cell subpopulations, indicating successful establishment of the GCSCs model. COE treatment significantly inhibited the spheroid formation ability of GCSCs and reduced the percentage of CD44⁺/CD24⁺ and ALDH⁺ cell subpopulations. The western blot analysis showed a significant decrease of Nanog, Oct-4, SOX-2, and EIF3H expression and an increase of PDCD4 expression in GCSCs after COE treatment in a concentration-dependent manner. COE treatment also significantly upregulated the mRNA expression of PDCD4 in GCSCs. In addition, COE displayed a strong inhibitory effect on the tumor-initiating ability of GCSCs in vivo and upregulated PDCD4 and downregulated EIF3H expression in xenograft tissues.

CONCLUSION

COE may be able to inhibit GC growth by suppressing the stemness of GCSCs via regulating PDCD4 and EIF3H expression.

Targeting NF-κB mediated cell signaling pathway and inflammatory mediators by 1,2-diazole in A549 cells in vitro

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1,2-Diazole suppresses TNF-α induced MMP-2 expression.

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1,2-Diazole abrogate NF-κB activation and regulate cytokines.

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It exhibits potent in vitro anticancer effect against A549 cells.

Lung cancer is the leading cause of cancer deaths globally. The objective of this study was to investigate the effect of 1,2-diazole (pyrazole) as an anti-cancer drug on human non-small cell lung carcinoma A549 cells. We attempt to examine the expression level of pro-inflammatory proteins such as TNF-α, NF-κB-p65, MMP-2 and E-Cadherin which are commonly associated with an inflammatory response in epithelial cells and apoptosis in A549 cells. The LPS-induced cytokines and inflammatory mediators include TNF-α, IL-6, iNOS and COX-2 levels in A549 cells and the effect of pyrazole was studied. The present study reveals that, pyrazole inhibits A549 cells by suppressing TNF-α induced MMP-2 expression, thereby inhibiting the nuclear translocation of NF-κB-p65. Pyrazole significantly up-regulate the E-cadherin level and down-regulated MMP-2 expression that could probably preventing A549 cancer cells to invade. The study further substantiated the anti-cancer property of pyrazole by regulating the above mentioned level of LPS-induced cytokines and inflammatory mediators. The observations of the present study open a possibility for the development of an effective therapeutic agent that targets inflammatory and signaling pathway mediators to challenge human non-small cell lung carcinoma.

Inhibition or Reversal of the Epithelial-Mesenchymal Transition in Gastric Cancer: Pharmacological Approaches

Epithelial-mesenchymal transition (EMT) constitutes one of the hallmarks of carcinogenesis consisting in the re-differentiation of the epithelial cells into mesenchymal ones changing the cellular phenotype into a malignant one. EMT has been shown to play a role in the malignant transformation and while occurring in the tumor microenvironment, it significantly affects the aggressiveness of gastric cancer, among others. Importantly, after EMT occurs, gastric cancer patients are more susceptible to the induction of resistance to various therapeutic agents, worsening the clinical outcome of patients. Therefore, there is an urgent need to search for the newest pharmacological agents targeting EMT to prevent further progression of gastric carcinogenesis and potential metastases. Therapies targeted at EMT might be combined with other currently available treatment modalities, which seems to be an effective strategy to treat gastric cancer patients. In this review, we have summarized recent advances in gastric cancer treatment in terms of targeting EMT specifically, such as the administration of polyphenols, resveratrol, tangeretin, luteolin, genistein, proton pump inhibitors, terpenes, other plant extracts, or inorganic compounds.

Anticancer activities of TCM and their active components against tumor metastasis

Traditional Chinese Medicine (TCM) has the characteristics of multiple targets, slight side effects and good therapeutic effects. Good anti-tumor effects are shown by Traditional Chinese Medicine prescription, Chinese patent medicine, single Traditional Chinese Medicine and Traditional Chinese medicine monomer compound. Clinically, TCM prolonged the survival time of patients and improved the life quality of patients, due to less side effects. Cancer metastasis is a complex process involving numerous steps, multiple genes and their products. During the process of tumor metastasis, firstly, cancer cell increases its proliferative capacity by reducing autophagy and apoptosis, and then the cancer cell capacity is stimulated by increasing the ability of tumors to absorb nutrients from the outside through angiogenesis. Both of the two steps can increase tumor migration and invasion. Finally, the purpose of tumor metastasis is achieved. By inhibiting autophagy and apoptosis of tumor cells, angiogenesis and EMT outside the tumor can inhibit the invasion and migration of cancer, and consequently achieve the purpose of inhibiting tumor metastasis. This review explores the research achievements of Traditional Chinese Medicine on breast cancer, lung cancer, hepatic carcinoma, colorectal cancer, gastric cancer and other cancer metastasis in the past five years, summarizes the development direction of TCM on cancer metastasis research in the past five years and makes a prospect for the future.

Protein tyrosine phosphatase L1 represses endothelial-mesenchymal transition by inhibiting IL-1β/NF-κB/Snail signaling

Endothelial-mesenchymal transition (EnMT) plays a pivotal role in various diseases, including pulmonary hypertension (PH), and transcription factors like Snail are key regulators of EnMT. In this study we investigated how these factors were regulated by PH risk factors (e.g. inflammation and hypoxia) in human umbilical vein endothelial cells (HUVECs). We showed that treatment with interleukin 1β (IL-1β) induced EnMT of HUVECs via activation of NF-κB/Snail pathway, which was further exacerbated by knockdown of protein tyrosine phosphatase L1 (PTPL1). We demonstrated that PTPL1 inhibited NF-κB/Snail through dephosphorylating and stabilizing IκBα. IL-1β or hypoxia could downregulate PTPL1 expression in HUVECs. The deregulation of PTPL1/NF-κB signaling was validated in a monocrotaline-induced rat PH (MCT-PH) model and clinical PH specimens. Our findings provide novel insights into the regulatory mechanisms of EnMT, and have implications for identifying new therapeutic targets for clinical PH.

28-Hydroxy-3-oxoolean-12-en-29-oic Acid, a Triterpene Acid from Celastrus Orbiculatus Extract, Inhibits the Migration and Invasion of Human Gastric Cancer Cells In Vitro

Gastric cancer is the fifth most common tumor and has the third-highest mortality rate among various malignant tumors, and the survival rate of patients is low. Celastrus orbiculatus extract has been shown to inhibit the activity of a variety of tumors. This study explored the inhibitory effect of the oleanane-type triterpenoid acid 28-hydroxy-3-oxoolean-12-en-29-oic acid molecule from Celastrus orbiculatus extract on gastric cancer cell invasion and metastasis and determined its mechanism. 28-Hydroxy-3-oxoolean-12-en-29-oic acid was first diluted to various concentrations and then used to treat SGC-7901 and BGC-823 cells. Cell proliferation was assessed by an MTT (thiazole blue) assay. Transwell and wound healing assays were used to assess cell invasion and migration. High-content imaging technology was used to further observe the effects of the drug on cell invasion and migration. Western blotting was used to assess the effects on the expression of matrix metalloproteinases (MMPs) and the effects on epithelial-mesenchymal transition (EMT)-related proteins and phosphorylation-related proteins. We found that 28-Hydroxy-3-oxoolean-12-en-29-oic acid inhibited the migration and invasion of SGC-7901 and BGC-823 gastric cancer cells in a dose-dependent manner. Consequently, 28-hydroxy-3-oxoolean-12-en-29-oic acid decreased the expression of EMT-related proteins and MMPs in gastric cancer cells and reduced protein phosphorylation, inhibiting the migration and invasion of gastric cancer cells.

Traditional uses, secondary metabolites, and pharmacology of Celastrus species - a review

ETHNOPHARMACOLOGICAL RELEVANCE

Plants of genus Celastrus (Celastraceae) have been widely used in traditional Chinese medicine (TCM) and Indian medicine to treat cognitive dysfunction, epilepsy, insomnia, rheumatism, gout, and dyspepsia for thousands of years.

AIM OF STUDY

We critically summarized the current evidence on the botanic characterization and distribution, ethnopharmacology, secondary metabolites, pharmacological activities, qualitative and quantitative analysis, and toxicology of Celastrus species to provide perspectives for developing more attractive pharmaceuticals of plant origin.

MATERIALS AND METHODS

The relevant information on Celastrus species was gathered from worldwide accepted scientific databases via electronic search (Web of Science, SciFinder, PubMed, Elsevier, SpringerLink, Wiley Online, China Knowledge Resource Integrated, and Google Scholar). Information was also obtained from the literature and books as well as PhD and MSc dissertations. Plant names were validated by "The Plant List" (www.theplantlist.org).

RESULTS

Comprehensive analysis of the above mentioned databases and other sources confirmed that ethnomedical uses of plants of Celastrus genus had been recorded in China, India, and other countries in Southern Asia. The phytochemical investigation revealed the presence of β-dihydroagarofuranoids, diterpenoids, triterpenoids, tetraterpenes, phenylpropanoids, alkaloids, flavonoids, lignans, and others. The crude extracts and isolated constituents have exhibited a wide range of in vitro and in vivo pharmacological effects, including antitumor, cytotoxic, insecticidal, antimicrobial, anti-rheumatoid arthritis (RA), anti-inflammatory, anti-ageing and antioxidative, and neuroprotective activities.

CONCLUSION

Plants of genus Celastrus have been confirmed to show a strong potential for therapeutic and health-maintaining effects, in light of their long traditional use and the phytochemical and pharmacological studies summarized here. Currently, pharmacological studies of this genus mainly focus on Celastrus paniculatus Willd. and Celastrus orbiculatus Thunb. Therefore, more pharmacological investigations should be implemented to support traditional uses of other medicinal plants of the genus Celastrus. Moreover, studies on the toxicity, bioavailability, and pharmacokinetics, in addition to clinical trials, are indispensable for assessing the safety and efficacy of the secondary metabolites or extracts obtained from plants belonging to this genus.

Celastrus orbiculatus Extracts Inhibit Human Hepatocellular Carcinoma Growth by Targeting mTOR Signaling Pathways

OBJECTIVE

To characterize the molecular mechanism underlying the antineoplastic activity of Celastrus orbiculatus Thunb. extracts (COE).

METHODS

The human hepatocellular carcinoma HepG2 cells with mammalian target of rapamycin (mTOR) knockdown expressed (HepG2/mTOR) were constructed using molecular biological technology. In vitro, the HepG2/mTOR^- cells were treated with COE at various concentrations (10, 20, 40, 80, 160 and 320 µ g/mL). Cell viability was determined using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assays. According to the half-maximal inhibitory concentration (IC₅₀) value (140 mg/L), the concentrations of COE in the subsequent experiment was set to alleviate cytotoxicity. The HepG2/mTOR^- cells were divided into 5 groups: negative control (untreated), COE treatment groups (40, 80, 120 mg/L COE) and positive control group (cisplatin, DDP, 2 mg/L), respectively. Wild-type HepG2 cells were used as a blank control. The effects of COE on the cell apoptosis were analyzed by flow cytometry and transmission electronic microscopy (TEM), respectively. The protein expression levels of mTOR signal pathways were determined by Western blotting. In vivo, HepG2/mTOR^- cells (2 × 10⁶ cell/mice) were subcutaneously injected into the right flank of nude mice. Thirty-six female nude mice were randomly assigned to 6 groups according to body weight (6 mice per group) as follows: solvent vehicle control, Banmao Capsule treated group (BM, 195 mg/kg), Tegafur, Gimeracil and Oteracil Potassium Capsules (10 mg/kg) treated group, and different dosages of COE (10, 20, 40 mg/kg) groups. Tumor growth was monitored and immunohistochemical staining was used to examine the expression of apoptosis-related proteins in tumor tissues.

RESULTS

COE inhibited the proliferation significantly in a concentration-dependent manner in HepG2/mTOR^- cells (P<0.01). COE significantly induced the apoptosis of HepG2/mTOR^- cells (P<0.01), and the apoptotic bodies can be observed under TEM. COE significantly inhibits the proteins expression of mTOR-related signal pathways. In vivo, COE significantly inhibited tumor growth in nude mice (P<0.01). Moreover, the results showed that COE down-regulated the expression of Bcl-2 and Bcl-xL, and up-regulated the levels of Bax and caspase-3 protein (P<0.01).

CONCLUSION

COE was a potential chemotherapeutic drug in HCC treatments via targeting mTOR signal pathway.

Effect of Celastrus orbiculatus in inhibiting Helicobacter pylori induced inflammatory response by regulating epithelial mesenchymal transition and targeting miR-21/PDCD4 signaling pathway in gastric epithelial cells

BACKGROUND

The extract of Celastrus orbiculatus (COE) have been studied for anti-Helicobacter pylori (H. pylori) activity and anti-cancer effects in vitro and in vivo. However, the molecular mechanism by which COE inhibits H. pylori-induced inflammatory response has not been fully elucidated so far.

METHODS

The effects of COE on viability, morphological changes, inflammatory cytokine secretion, protein and mRNA expression were analyzed by MTT assay, enzyme-linked immunosorbent assay (ELISA), immunofluorescence, western blot and real-time PCR (RT-PCR), respectively. The methylation level of programmed cell death 4 (PDCD4) promoter was investigated by methylation-specific PCR. (MSP) .

RESULTS

COE effectively inhibited the H.pylori-induced inflammatory response by regulating epithelial-mesenchymal transition (EMT). The methylation level of PDCD4 promoter was suppressed by COE, which increased the expression ofPDCD4. Moreover, COE could inhibit microRNA-21 (miR-21) expression, as shown by an enhancement of its target gene PDCD4. Furthermore, both miR-21 over-expression and PDCD4 silencing attenuated the anti-inflammatory effect. of COE.

CONCLUSIONS

COE inhibits H. pylori induced inflammatory response through regulating EMT, correlating with inhibition of miR-21/PDCD4 signal pathways in gastric epithelial cells.

Impact of gene polymorphism of TNF-α rs 1800629 and TNF-β rs 909253 on plasma levels of South Indian breast cancer patients

AIM

Inflammation plays a lead role in the tumor microenvironment and promotes metastasis. Single-nucleotide polymorphism (SNP) in the tumor necrosis factor (TNF) gene locus may alter the expression of genes and proteins. The objective of the study is to find the distribution of genetic polymorphism in the sites of TNF-α -308G>A and TNF- β +252A>G in breast cancer and evaluate polymorphism effects on plasma levels.

MATERIALS AND METHODS

The study group consisted of 109 invasive ductal primary breast cancer patients and 75 age-matched healthy female controls. Plasma cytokine concentrations were measured by the MILLIPLEX^® MAP Human Cytokine/Chemokine Panel magnetic bead kits. The genotyping procedure for SNP included allele-specific polymerase chain reaction for TNFα and restriction fragment length polymorphism for TNFβ.

RESULTS

Odds ratio with 95% confidence interval showed that these polymorphisms were not a causative risk factor, and both polymorphisms were consistent with Hardy-Weinberg equilibrium. Plasma TNFα and TNFβ median concentrations were significantly higher in cases when compared to controls (P < 0.01). When plasma TNFα levels were grouped under polymorphic subtypes, patients with mutant TNF- α -308A allele showed significantly higher values (P < 0.001). In addition, plasma TNFα values were significantly elevated in mutant TNF-β +252G allele (P < 0.01).

CONCLUSION

This study demonstrated that there is no significant association between SNPs and breast cancer susceptibility in South Indian population. However, plasma TNFα level is significantly elevated with mutant-recessive TNF-α -308 A and TNF-β +252 G alleles of patients.

HOXB9 inhibits proliferation in gastric carcinoma cells via suppression of phosphorylated-Akt and NF-κB-dependent Snail expression

BACKGROUND

HOXB9 is a homeobox transcription factor which plays an important role in carcinoma development. This protein has been shown to inhibit cancer cell proliferation. However, the mechanisms that underpin HOXB9-mediated inhibition of cellular proliferation remain to be elucidated.

METHODS

In this study, two gastric cancer cell lines, SGC7901 and MKN45, were transfected with plasmids pLVX-HOXB9 and shHOXB9. These transfections resulted in the over-expression of the HOXB9 gene in the SGC7901/HOXB9 cells and knockdown of the HOXB9 gene in the MKN45/shHOXB9 cells.

RESULTS

Over-expression of the HOXB9 gene in the SGC7901/HOXB9 cells caused an increase in the apoptotic rate and a concomitant reduction in metastatic ability compared with the knocked-down MKN45/shHOXB9 cells. Moreover, a reduction in the expression of the phosphorylated-Akt protein was observed in the SGC7901/HOXB9 cells, while an increase in expression of the same protein was observed in the MKN45/shHOXB9 cells. We also observed that HOXB9 mediated a reduction in both NF-κB and N-cadherin and Snail protein expression. Conversely, HOXB9 caused an increase in the expression of E-cadherin.

CONCLUSIONS

In summary, this study reports that HOXB9 can suppress both phosphorylated-Akt expression and NF-κB activity. The latter phenomenon affects Snail protein expression and the inhibition of gastric carcinoma proliferation.

Celastrus orbiculatus extracts induce apoptosis in mTOR-overexpressed human hepatocellular carcinoma HepG2 cells

Background

Celastrus orbiculatus (Celastraceae) are used as traditional Chinese medicine to treat inflammation and cancer. This study aims to evaluate the effect of Celastrus orbiculatus extract (COE) on the apoptosis in human hepatic carcinoma HepG2 cells with mTOR overexpression.

Methods

The stable expression of mTOR in HepG2 cells (HepG2/mTOR⁺) were established by lipofectin transfection of GV238-mTOR recombinant plasmids and further antibiotic selection. Human hepatic carcinoma HepG2/mTOR⁺ cells were treated with different concentrations (20, 40, 80, 160, and 320 μg/mL) of COE for 24 h. The cell proliferation upon COE treatment was detected by MTT. Apoptosis was measured by Flow Cytometry. The activity of mTOR signaling pathway was detected by Western Blotting.

Results

COE significantly inhibited the proliferation of HepG2/mTOR⁺ cells. The expression levels of Bax and Caspase-3 protein were increased in the HepG2/mTOR⁺ cells in a dose-dependent manner. The proteins expression of Bcl2, Bcl-2 L12, mTOR, phospho-mTOR, 4EBP1, phospho-4EBP1, P70S6k, and phospho-P70S6k in HepG2/mTOR⁺ cells were reduced in dose-dependent manners. Furthermore, COE and mTOR inhibitor rapamycin (RAPA) synergistically induced apoptosis in HepG2/mTOR⁺ cells by regulating apoptosis-related proteins and inhibiting mTOR signaling pathways.

Conclusion

COE could inhibit the proliferation of HepG2/mTOR⁺ cells, and induce the cell apoptosis. The mechanisms may be related to the regulation of the expression of Bcl-2, Bcl-2 L12, and mTOR signaling pathways. These data suggest that COE may be a potential treatment for human hepatocellular carcinoma.

Effects of Celastrus orbiculatus on Epithelial Mesenchymal Transition in Gastric Mucosal Epithelial Cells by Inhibiting Lgr5 Expression from Rats with Gastric Precancerous Lesions

The extract of Celastrus orbiculatus (COE) has been shown to possess anti-Helicobacter pylori (H. pylori) activity and anticancer effects in vitro and in vivo. However, the molecular mechanism by which COE on precancerous lesions of gastric cancer (PLGC) has not been fully elucidated so far. The purpose of this study is to evaluate the effect and mechanism of COE in the rat model of PLGC, after the rat model of PLGC was successfully constructed. The effects of COE in gastric mucosa of rats with PLGC were tested using routine pathology and a transmission electron microscope (TEM) analysis. The protein and mRNA expression levels of epithelial mesenchymal transition (EMT) markers (E-cadherin, N-cadherin and Vimentin) and leucine-rich repeat-containing G-protein-coupled receptor 5 (Lgr5) were detected adopting techniques of immunohistochemistry (IHC), real-time PCR (RT-PCR) and western blot assays. The body weight of PLGC rats was significantly higher in the COE group than that in the untreated group. The process of PLGC was significantly reversed after COE treatment, shown by observing the changes of histopathological morphology and ultrastructure. Gastric mucosal epithelial cells in COE high dose (COE-H) group showed significantly higher expression levels of E-cadherin, and lower expression levels of N-cadherin, Vimentin and Lgr5 than those of the untreated group. COE could suppress the spatial distribution of Lgr5[Formula: see text] cell changes in PLGC rats. These findings suggested that the therapeutic mechanisms of COE in treating PLGC might be related with its effects on reversing the EMT process and inhibiting Lgr5 expression.

Efficacy of extracts of Celastrus orbiculatus in suppressing migration and invasion by inhibiting the EZH2/ROCK1 signaling pathway in human nasopharyngeal carcinoma

Celastrus orbiculatus extract (COE) has been used in folk medicine in China for the treatment of a number of diseases. In the laboratory, COE exhibits a variety of anticancer functions, including inhibition of metastasis. However, the underlying molecular anti-metastatic mechanism in nasopharyngeal carcinoma (NPC) cells remains unclear. The aim of the present study was to determine whether the anti-metastatic effect of COE was involved in inhibiting migration and invasion of human NPC cells. In vitro, cell viability and apoptosis of 5-8F cells were analyzed using an MTS assay and flow cytometry, respectively. Invasion and migration of 5-8F cells were analyzed using a Transwell assay. Protein and mRNA expression levels of 5-8F cells were analyzed by western blot analysis and the reverse transcription-quantitative polymerase chain reaction, respectively. COE significantly decreased cell viability in 5-8F cells and inhibited enhancer of zeste homolog 2 (EZH2) and Rho-associated coiled coil-containing protein kinase 1 (ROCK1) expression at the mRNA and protein levels. Furthermore, COE decreased the migration and invasion of 5-8F cells in a dose-dependent manner. The results of the present study suggested that COE prevents migration and invasion by suppressing the EZH2/ROCK1 signaling pathway in NPC cells. On the basis of the results of the present study, COE may be a novel anticancer agent for the treatment of metastasis in NPC.

Celastrus orbiculatus extracts induce cell cycle arrest and apoptosis in human esophageal squamous carcinoma ECA-109 cells in vitro via the PI3K/AKT/mTOR signaling pathway

Recently, Celastrus orbiculatus ethyl acetate extracts (COE) have been investigated for their anticancer effects on digestive tract tumors. However, the therapeutic effects of COE on esophageal squamous carcinoma cells (ESCC) have not been investigated. In the present study, the effects of COE on the cell cycle and apoptosis of ESCCs were assessed in vitro, and it was revealed that COE treatment triggered G₀/G₁ cell cycle arrest, and induced DNA damage and apoptosis in a dose-dependent manner in ESCC. Activation of the phosphatidylinositol 3-kinase/protein kinase-B/mechanistic target of rapamycin (mTOR) pathway was also suppressed by COE. Additionally, the combined treatment with COE and rapamycin (an mTOR inhibitor) acted synergistically in ECA-109 cells compared with the treatment with COE or rapamycin alone. These findings extend the understanding of the action of COE and suggest that COE has potential as a treatment option for ESCC as a single treatment or in combination.

Celastrus orbiculatus extracts induce apoptosis and inhibit invasion by targeting the maspin gene in human gastric adenocarcinoma cells

Celastrus orbiculatus Thunb. has been used as a remedy against cancer and inflammatory diseases for thousands of years in China. Maspin is expressed in normal cells and downregulated in prostate tumor cells. The underlying mechanisms between C. orbiculatus extract (COE) and maspin remain unclear. In the present study, 3 target-specific 19–25 nucleotide maspin small interfering RNAs were designed and synthesized to knockdown maspin expression. The effects of COE on MGC-803/maspin⁻ cell proliferation were evaluated by the MTT assay. Apoptosis was measured by flow cytometry. Invasive activity was measured with the Transwell assay and the associated molecular mechanisms were assessed by western blot analysis. The results demonstrated that COE significantly promoted the expression of maspin (P<0.01) to induce apoptosis and inhibit invasion and migration in MGC803 cells. The expression levels of phosphorylated (p)-p38 mitogen-activated protein kinase (MAPK), phospho-extracellular regulated protein kinase (Erk), B cell lymphoma-2-associated X protein and caspase-3 were increased in the MGC-803/maspin⁻ cells in a dose-dependent manner. The Erk, B-cell lymphoma 2, p-Akt, Akt and p-mechanistic target of rapamycin (mTOR) protein in MGC-803/maspin⁻ cells were reduced in a dose-dependent manner. This indicated that COE may inhibit invasion and migration through phosphoinositide 3-kinase/Akt/mTOR and MAPK signaling pathways in MGC-803/maspin⁻ cells. In conclusion, COE has the ability to improve the expression of maspin to induce apoptosis and inhibit invasion and migration in human gastric adenocarcinoma cells.

COE inhibits vasculogenic mimicry in hepatocellular carcinoma via suppressing Notch1 signaling

ETHNOPHARMACOLOGICAL RELEVANCE

Vasculogenic mimicry (VM) has been suggested to be present in various malignant tumors and associated with tumor nutrition supply and metastasis, leading to poor prognosis of patients. Notch1 has been demonstrated to contribute to VM formation in hepathocellular carcinoma (HCC). Celastrus orbiculatus extract (COE), a mixture of 11 terpenoids isolated from the Chinese Herb Celastrus orbiculatus Vine, has been suggested to be effective in cancer treatment.

AIM OF THE STUDY

In the current study, experiments were carried out to examine the effect of COE on VM formation and HCC tumor growth both in vitro and in vivo.

MATERIALS AND METHODS

CCK-8 assay and Nikon live-work station were used to observe the viability of malignant cells treated with COE. Cell invasion was examined using Transwell. Matrigel was used to establish a 3-D culture condition for VM formation. Changes of mRNA and protein expression were examined by RT-PCR and Western Blot respectively. Tumor growth in vivo was monitored using in vivo fluorescence imaging device. PAS-CD34 dual staining and electron microscopy were used to observe VM formation. Immunohistochemical staining (IHC) was used to examine Notch1 and Hes1 expression in tumor tissues.

RESULTS

Results showed that COE can inhibit HCC cells proliferation and invasion in a concentration-dependent manner. VM formation induced by TGF-β1 was blocked by COE. In mouse xenograft model, COE inhibited tumor growth and VM formation. Both in vitro and in vivo studies showed that COE can downregulate expression of Notch1 and Hes1.

CONCLUSION

The current results indicate that COE can inhibit VM formation and HCC tumor growth by downregulating Notch1 signaling. This study demonstrates that COE is superior to other anti-angiogenesis agents and can be considered as a promising candidate in HCC treatment.

Anticancer efficacy of the ethyl acetate extract from the traditional Chinese medicine herb Celastrus orbiculatus against human gastric cancer

ETHNOPHARMACOLOGICAL RELEVANCE

The traditional Chinese medicine (TCM) herb Celastrus orbiculatus is an important folk medicinal plant in China that has been used as an anti-inflammatory, antitumor, and analgesic in various diseases. The ethyl acetate extract of C. orbiculatus (C. orbiculatus extract, COE) was reported to show significant antitumor effects. However, no study in China or abroad has reported the effect and mechanism of COE in triggering apoptosis of gastric cancer (GC) cells.

AIM OF STUDY

To further uncover the molecular mechanism underlying COE's apoptotic and anti-proliferative effects and lay a foundation for the development of novel, effective antitumor TCM agents.

MATERIALS AND METHODS

The effect of COE on AGS and BGC-823 GC cell viability was examined using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis of AGS and BGC-823 cells induced by COE was analyzed using flow cytometry and a mitochondrial membrane potential assay kit (JC-1). The proliferating GC cells were identified and examined using a 5-bromo-2'-deoxyuridine (BrdU) staining kit and flow cytometric analysis. A western blot assay was used to detect the effect of COE on apoptosis-related proteins, B-cell lymphoma-2 (Bcl-2), Bcl-extra-large (Bcl-xL), Bcl-2-like protein 12 (Bcl-L12), Bcl-2-associated X protein (Bax), and caspase as well as proliferation-related proteins, phosphoinositide 3-kinase (PI3K)/Akt/mechanistic target of rapamycin (mTOR)/p70s6k. Transmission electron microscopy (TEM) and an animal imaging technique were used to evaluate the microstructure of apoptotic GC cells and the effect of COE on tumor cell growth in vivo, respectively.

RESULTS

The results indicate that COE significantly inhibited proliferation and induced apoptosis of GC AGS and BGC-823 cell lines both in vivo and in vitro. COE significantly decreased the cell mitochondrial membrane potential. Moreover, COE downregulated the levels of Bcl-2, Bcl-xL, and PI3K/Akt/mTOR/p70s6k while those of Bax and caspase were upregulated. More interestingly, COE altered the microstructure of the mitochondria.

CONCLUSION

All these data collectively indicate that COE not only has significant antiproliferative effects but also has both in vivo and in vitro apoptotic effects. In addition, COE altered the structure and function of the mitochondria, which is another potential pathway for the antitumor activity of COE. These findings may provide a basis for the development of new anticancer TCM candidates.

TNF-Alpha Promotes Invasion and Metastasis via NF-Kappa B Pathway in Oral Squamous Cell Carcinoma

Background

Recent evidence reveals that the inflammatory microenvironment is associated with tumor migration, invasion, and metastasis. Tumor necrosis factor-α (TNF-α) play a vital role in regulation of the inflammatory process in tumor development. Nuclear factor-kappa B (NF-κB) is one of the key transcription factors which regulate processes in tumor promotion. The aim of this study was to explore the role of NF-κB on the invasion and migration of oral squamous cell carcinoma (OSCC).

Material/Methods

The IKKβ and p65 mRNA and protein levels were determined by quantitative RT-PCR and western blot. Wound scratch healing assays and transwell migration assays were used to evaluate the effect of TNF-α and BAY11-7082 on the migration of the OSCC cell lines (HN4, HN6, and CAL27).

Results

We observed a significant increase of the expression level of IKKβ and p65 in OSCC cells from the experimental group at 24 h, 48 h, and 72 h after TNF-α stimulation. Invasion and metastasis of OSCC cells was obviously improved after the TNF-α stimulation. Invasion and metastasis ability of OSCC cells was inhibited in the suppression group, and no significant changes were observed in expression level of IKKβ and p65 after the use of BAY11-7082.

Conclusions

Our results suggest that TNF-α enhances the invasion and metastasis ability of OSCC cells via the NF-κB signaling pathway.

Celastrus orbiculatus extract triggers apoptosis and autophagy via PI3K/Akt/mTOR inhibition in human colorectal cancer cells

Celastrus orbiculatus is used as a folk medicine in China for the treatment of numerous diseases. The ethyl acetate extract of Celastrus orbiculatus (COE) also displays a wide range of anti-cancer activities in the laboratory. However, the effectiveness of COE-induced autophagy and its mechanism of action in colorectal cancer cells have not been investigated thus far. The present study analyzed the effect of COE on HT-29 cell viability, apoptosis and autophagy using MTT assay, flow cytometry, transmission electron microscopy and western blotting. Additionally, the autophagy inhibitor 3-methyladenine and the autophagy inducer rapamycin were used to further explore the effects of COE-induced autophagy in HT-29 cells. The present study also examined whether the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/Akt/mechanistic target of rapamycin (mTOR)/p70 ribosomal protein S6 kinase (p70S6K) signaling pathway was involved in the regulation of COE-induced autophagy. The results revealed that COE inhibited HT-29 cell proliferation and decreased cell survival in a time- and dose-dependent manner, and that COE possessed the ability to induce both apoptosis and autophagy in HT-29 cells. Furthermore, autophagy and apoptosis induced by COE synergized to inhibit colorectal cancer growth. In addition, COE treatment decreased the phosphorylation of Akt and its downstream effectors mTOR and p70S6K. Taken together, these results demonstrate that both autophagy and apoptosis were activated during COE treatment of HT-29 cells, and that COE-induced autophagy decreases the viability of HT-29 cells via a mechanism that may depend on the PI3K/Akt/mTOR/p70S6K signaling pathway. Furthermore, compounds that induce autophagy administered in combination with COE may be an attractive strategy for enhancing the anti-tumor potency of COE in colorectal cancer.

Distinct routes to metastasis: plasticity-dependent and plasticity-independent pathways

The cascade that culminates in macrometastases is thought to be mediated by phenotypic plasticity, including epithelial–mesenchymal and mesenchymal–epithelial transitions (EMT and MET). Although there is substantial support for the role of EMT in driving cancer cell invasion and dissemination, much less is known about the importance of MET in the later steps of metastatic colonization. We created novel reporters, which integrate transcriptional and post-transcriptional regulation, to test whether MET is required for metastasis in multiple in vivo cancer models. In a model of carcinosarcoma, metastasis occurred via an MET-dependent pathway; however, in two prostate carcinoma models, metastatic colonization was MET independent. Our results provide evidence for both MET-dependent and MET-independent metastatic pathways.