Development of actein derivatives as potent anti-triple negative breast cancer agents.

Actein is a natural triterpenoid glycoside, isolated from the rhizomes of Cimicifuga foetida, which have been demonstrated to be potential in the treatment of breast cancer previously. Herein, we described the design and synthesis of a series of actein derivatives as anti-triple negative breast cancer (TNBC) inhibitors. Of which, the most promising derivative 27 exhibited significant inhibitory activity against human TNBC cell lines HCC1806 and MDA-MB-231, with IC50 values of 2.78 and 9.11 µM, respectively. Structure-activity relationships of actein derivatives were also discussed. Moreover, preliminary mechanism investigation revealed that 27 significantly inhibited cancer cell proliferation via cell cycle arrest at S phase. In addition, western blot analysis showed that the activation of MAPK signaling pathway might contribute to derivative 27 induced cell death. Overall, these results indicate that 27 has the potential to be developed as a lead compound and compounds with the actein scaffold are a promising novel class of inhibitors to treat TNBC.

Actein contributes to black cohosh extract-induced genotoxicity in human TK6 cells.

Black cohosh extract (BCE) is one of the most popular botanical products for relieving menopausal symptoms. However, recent studies indicate that BCE is not only ineffective for menopausal therapy but also induces genotoxicity through an aneugenic mode of action (MoA). In this study, the cytotoxicity of five constituents of BCE was evaluated in human lymphoblastoid TK6 cells. Among the five constituents, actein (up to 50 µM) showed the highest cytotoxicity and was thus selected for further genotoxicity evaluations. Actein caused DNA damage proportionally to concentration as evidenced by the phosphorylation of the histone protein H2A.X (γH2A.X) and resulted in chromosomal damage as measured by the increased percentage of micronuclei (%MN) in cells. In addition, actein activated DNA damage response (DDR) pathway through induction of p-ATM, p-Chk1, and p-Chk2, which subsequently induced cell cycle changes and apoptosis. Moreover, both BCE and actein increased intracellular reactive oxygen species (ROS) production, decreased glutathione levels, and activated the mitogen-activated protein kinases (MAPK) signaling pathway. N-acetylcysteine, a ROS scavenger, attenuated BCE- and actein-induced ROS production, apoptosis, and DNA damage. These findings indicate that BCE- and actein-induced genotoxicity is mediated, at least partially, through oxidative stress. Taken together, our data show that actein is likely one of the major contributors to BCE-induced genotoxicity.

Actein Antagonizes Oral Squamous Cell Carcinoma Proliferation through Activating FoxO1.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is among the most prevalent head and neck malignancies globally, and it is associated with high mortality rates. Actein is one of the primary active components extractable from the rhizomes of Cimicifuga foetida. This study aimed to evaluate the anti-OSCC effects of actein and evaluate the potential underlying mechanisms. METHODS AND RESULTS: CCK-8 cell proliferation experiments demonstrated significant dose- and time-dependent anti-OSCC effects of actein, while actein had weak cytotoxic effects on normal oral cell lines. Flow cytometry for cell cycle evaluation revealed that actein could induce cell cycle arrest at the G1 phase among OSCC cell lines. In our Annexin V/PI double staining apoptosis analysis, actein induced significant apoptosis among OSCC cells, with upregulation of Bax and downregulation of Bcl-2. Our mechanistic study implicated the involvement of the Akt/FoxO1 pathway in the anti-OSCC effects of actein. Akt1 and Akt2 expression significantly decreased in association with the FoxO1 upregulation. Furthermore, Bim and p21 were significantly upregulated, while survivin expression was downregulated. Finally, actein treatment was associated with significant p-Akt downregulation and p-FoxO1 upregulation in OSCC cells, demonstrating the validated roles of Akt/FoxO1 in actein-mediated OSCC cell apoptosis and cell cycle arrest. FoxO1 knockdown significantly reversed the anti-OSCC effects of actein. Additionally, a xenograft model indicated that actein could inhibit OSCC cell growth in vivo. CONCLUSIONS: Our findings demonstrated that actein could be a strong anti-OSCC candidate. Further evaluations of its safety and effectiveness are necessary before it can be considered for clinical use.

Structure-Guided Identification of Black Cohosh (Actaea racemosa) Triterpenoids with In Vitro Activity against Multiple Myeloma.

Black cohosh is a well-established medicinal plant and preparations of its rootstock are used for the treatment of mild climacteric complaints. The compounds considered responsible for the therapeutic effect are triterpene glycosides, characterized by a cycloartane scaffold and a pentose moiety. Because some of these triterpenoids were found to exhibit relevant cytotoxic effects against human breast cancer cells, we decided to investigate their activity on multiple myeloma cell lines NCI-H929, OPM-2, and U266. In a systematic approach, we initially tested three known cytotoxic compounds of three different triterpenoid types, revealing the cimigenol-type triterpenoid as the most active constituent. In a second round, seven naturally occurring cimigenol derivatives were compared with respect to their sugar moiety and their substitution pattern at position C-25, leading to 25-O-methylcimigenol-3-O-α-L-arabinopyranoside as the most potent candidate. Interestingly, not only the methyl group at position C-25 increased the cytotoxic effect but also the arabinose moiety at position C-3 had an impact on the activity. The variety of cimigenol derivatives, moreover, allowed a detailed discussion of their structure-activity relationships, not only for their effect on multiple myeloma cells but also with regard to previous studies on the cytotoxicity of black cohosh triterpenoids.

Actein enhances TRAIL effects on suppressing gastric cancer progression by activating p53/Caspase-3 signaling.

Actein (ACT), isolated from the rthizomes of Cimicifuga foetida, is a triterpene glycoside, showing inhibitory role in breast cancer cells. However, the effects of ACT treatment on gastric cancer have little been known. Thus, the study is conducted to explore the in vitro and in vivo role of ACT in gastric cancer. And the interactions between ACT and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) were investigated in gastric cancer cells. A synergistic effect of ACT and TRAIL combination on apoptosis induction in gastric cancer cells was observed. The cancer cells were insensitive to TRAIL single therapy. However, gastric cancer cells receiving ACT were sensitive to TRAIL-triggered apoptotic response by enhancing Caspases cleavage, due to elevation of decoy receptor 1 and 2 (DcR1 and DcR2) dependent on p53. Bcl-2 family members of Bcl-2 and Mcl-1, belonging to anti-apoptosis, were decreased, whereas Bad and Bak, as pro-apoptotic members, were increased for ACT and TRAIL combined treatment. Additionally, the mouse xenograft model suggested that ACT and TRAIL in combination markedly inhibited gastric cancer growth in comparison to ACT or TRAIL monotherapy without toxicity. The present study revealed a dramatically therapeutic strategy for promoting TRAIL-induced anti-cancer effects on gastric cancer cells via ACT combination.

Actein alleviates 2,3,7,8-tetrachlorodibenzo-p-dioxin-mediated cellular dysfunction in osteoblastic MC3T3-E1 cells.

The environmental pollutant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is known to affect bone metabolism. We evaluated the protective effects of the triterpene glycoside actein from the herb black cohosh against TCDD-induced toxicity in MC3T3-E1 osteoblastic cells. We found that TCDD significantly reduced cell viability and increased apoptosis and autophagy in MC3T3-E1 osteoblastic cells (P < .05). In addition, TCDD treatment resulted in a significant increase in intracellular calcium concentration, mitochondrial membrane potential collapse, reactive oxygen species (ROS) production, and cardiolipin peroxidation, whereas pretreatment with actein significantly mitigated these effects (P < .05). The effects of TCDD on extracellular signal-related kinase (ERK), aryl hydrocarbon receptor, aryl hydrocarbon receptor repressor, and cytochrome P450 1A1 levels in MC3T3-E1 cells were significantly inhibited by actein. The levels of superoxide dismutase, ERK1, and nuclear factor kappa B mRNA were also effectively restored by pretreatment with actein. Furthermore, actein treatment resulted in a significant increase in alkaline phosphatase (ALP) activity and collagen content, as well as in the expression of genes associated with osteoblastic differentiation (ALP, type I collagen, osteoprotegerin, bone sialoprotein, and osterix). This study demonstrates the underlying molecular mechanisms of cytoprotection exerted by actein against TCDD-induced oxidative stress and osteoblast damage.

Actein protects against methylglyoxal-induced oxidative damage in osteoblastic MC3T3-E1 cells.

BACKGROUND: Methylglyoxal (MG) is an endogenous product of glucose metabolism known to be toxic to cells and to be present in elevated concentrations under certain pathophysiological conditions. In the present study the effect of actein isolated from black cohosh on MG-induced cytotoxicity was investigated in MC3T3-E1 osteoblastic cells. RESULTS: Treatment of MC3T3-E1 osteoblastic cells with actein prevented MG-induced cell death and the production of intracellular reactive oxygen species (ROS), mitochondrial superoxide, inflammatory cytokines and soluble receptor for advanced glycation end-products (sRAGE). In addition, actein increased the activity of glyoxalase I and levels of reduced glutathione (GSH) and the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2). These findings suggest that actein protects against MG-induced cell damage by reducing oxidative stress and increasing MG detoxification. Treatment with actein prior to MG exposure reduced MG-induced mitochondrial dysfunction by preventing mitochondrial membrane potential dissipation and adenosine triphosphate (ATP) loss. Additionally, peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α), nuclear respiratory factor 1 (NRF-1) and nitric oxide (NO) levels were significantly increased by actein, suggesting that actein may induce mitochondrial biogenesis. CONCLUSION: This study demonstrates that actein reduces MG-induced damage in osteoblastic MC3T3-E1 cells by enhancing antioxidant defenses, the glyoxalase system and mitochondrial biogenesis. © 2016 Society of Chemical Industry.

Salicylic Acid Treatment Increases the Levels of Triterpene Glycosides in Black Cohosh (Actaea Racemosa) Rhizomes.

Black cohosh (Actaea racemosa) serves as the host plant for the Appalachian azure butterfly, Celastrina neglectamajor. Overharvesting of Black cohosh for the dietary supplement industry may result in its extirpation, and may also cause the elimination of the dependent butterfly. One way to increase or maintain the number of host plants in forested environments would be to reduce the number harvested, for example by increasing the levels of the desired metabolites in Black cohosh rhizomes. The secondary metabolites actein and deoxyactein are triterpene glycosides and are among the compounds associated with the putative activity of Black cohosh extracts. Acetein and deoxyacetein are used to standardize Black cohosh supplements. To gain an understanding of mechanisms that may control actein and deoxyactein accumulation, Black cohosh rhizomes were treated with exogenous salicylic acid, jasmonic acid, or ethylene, or were mechanically wounded. Salicylic acid treatment significantly increased the levels of actein and deoxyactein in the rhizome of Black cohosh, suggesting that the synthesis of triterpene glycosides is controlled in part by salicylic acid. Using salicylic acid or related chemicals to increase the levels of actein and deoxyactein in rhizomes may help supply the supplement industry and, simultaneously, help conserve Black cohosh and species dependent upon it.

The in Vitro and in Vivo Antitumor Activities of Tetracyclic Triterpenoids Compounds Actein and 26-Deoxyactein Isolated from Rhizome of Cimicifuga foetida L.

AIMS: This work aims to study the in vitro and in vivo antitumor activities of tetracyclic triterpenoids compounds actein and 26-deoxyactein. Further, the mechanism is investigated. METHODS: In vitro, a modified MTT method was used to assay the cytotoxicities of actein and 26-deoxyactein in 12 human tumor cell lines. In vivo, mouse sarcoma S180 and human lung cancer A549 cells were respectively implanted subcutaneously in ICR mice and nude mice to establish implanted tumor models. Flow cytometry (FCM) was used to assay the cycle distribution of the tumor cells. Immunohistochemistry was used to measure CD31-positive expression in the xenogrft tumor by analyzing microvessel density (MVD). In addition, acute toxicities of actein and 26-deoxyactein were also evaluated. RESULTS: Actein and 26-deoxyactein inhibited the proliferation of the 12 human cancer cell lines tested with the values of 50% inhibitory concentrations (IC50) between 12.29 and 88.39 µg/mL. In vivo, both actein (3-27 mg/kg) and 26-deoxyactein (3-27 mg/kg) significantly inhibited the growth of the implanted sarcoma S180 in a dose-dependent manner. Actein (10, 30 mg/kg) and 26-deoxyactein (10, 30 mg/kg) markedly inhibited the xenograft growth with T/C (%) values of 38%, 55% for actein, and 35%, 49% for 26-deoxyactein. Compared with the vehicle control, actein (10, 30 mg/kg) and 26-deoxyactein (10, 30 mg/kg) significantly reduced the MVD in the xenograft tumor. The FCM result showed that human leukemia HL-60 cells were arrested at G1 phase after treated with either actein (6.25-25 µg/mL) or 26-deoxyactein (6.25-25 µg/mL) for 48 h. A limited trial in mice showed that both of the minimal lethal doses (MLDs) of actein and 26-deoxyactein were over 5 g/kg. CONCLUSIONS: Both actein and 26-deoxyactein have low toxicities. Importantly, both these two tetracyclic triterpenoids compounds isolated from rhizome of Cimicifuga foetida L. have significant antitumor activities in vitro and in vivo, which is associated with cell cycle arrest and angiogenesis inhibition.

Potential Targets of Actein Identified by Systems Chemical Biology Methods.

Actein is the main active ingredient of medicinal plant Cimicifuga racemosa (L.) Nutt, which has been reported to have various pharmacological effects, but the mechanism of actein remains undetermined. In this study, systems chemical biology methods were used to predict the targets and elucidate the pharmacological mechanisms of actein. First, 54 gene co-expression modules were obtained by biclustering. Then, the top 1 % agents with the highest regulatory similarity were screened out to be highly functionally similar to actein. Finally, the results of molecular docking and molecular dynamics simulation showed that actein has a stronger interaction with eight targets than original ligands. It suggests that the antipsychotic effect of actein probably occurs by targeting the key residues of the eight receptors, which are compatible with previously reported information. This study not only provides predicted targets of actein, but also a new method for exploring the mechanisms of other natural products in drug discovery.

Actaea racemosa L. extract inhibits steroid sulfation in human breast cancer cells: Effects on androgen formation.

BACKGROUND: Actaea racemosa L., also known as black cohosh, is a popular herb commonly used for the treatment of menopausal symptoms. Because of its purported estrogenic activity, black cohosh root extract (BCE) may trigger breast cancer growth. STUDY DESIGN/METHODS: The potential effects of standardized BCE and its main constituent actein on cellular growth rates and steroid hormone metabolism were investigated in estrogen receptor alpha positive (ERα+) MCF-7 and -negative (ERα-) MDA-MB-231 human breast cancer cells. Cell numbers were determined following incubation of both cell lines with the steroid hormone precursors dehydroepiandrosterone (DHEA) and estrone (E1) for 48 h, in the presence and absence of BCE or actein. Using a validated liquid chromatography-high resolution mass spectrometry assay, cell culture supernatants were simultaneously analyzed for the ten main steroids of the estrogen pathway. RESULTS: Inhibition of MCF-7 and MDA-MB-231 cell growth (up to 36.9%) was observed following treatment with BCE (1-25 µg/ml) or actein (1-50 µM). Incubation of MCF-7, but not of MDA-MB-231 cells, with DHEA and BCE caused a 20.9% reduction in DHEA-3-O-sulfate (DHEA-S) formation, leading to a concomitant increase in the androgens 4-androstene-3,17-dione (AD) and testosterone (T). Actein was shown to exert an even stronger inhibitory effect on DHEA-S formation in MCF-7 cells (up to 89.6%) and consequently resulted in 12- to 15-fold higher androgen levels compared with BCE. The formation of 17ß-estradiol (E2) and its glucuronidated and sulfated metabolites was not affected by BCE or actein after incubation with the estrogen precursor estrone (E1) in either cell line. CONCLUSIONS: The results of the present study demonstrated that actein and BCE do not promote breast cancer cell growth or influence estrogen levels. However, androgen formation was strongly stimulated by BCE and actein, which may contribute to their ameliorating effects on menopausal symptoms in women. Future studies monitoring the levels of AD and T upon BCE supplementation of patients are warranted to verify an association between BCE and endogenous androgen metabolism.

Actein Inhibits Tumor Growth and Metastasis in HER2-Positive Breast Tumor Bearing Mice via Suppressing AKT/mTOR and Ras/Raf/MAPK Signaling Pathways.

HER2-positive breast cancer accounts for 15-20% in breast cancer and 50% of the metastatic HER2-positive breast cancer patients died of central nervous system progression. The present study investigated the effects of actein (a natural cycloartane triterpene) on cells adhesion, migration, proliferation and matrix degradation, and its underlying mechanism in HER2-positive breast cancer cells. The in vivo effect of actein on tumor growth and metastasis in MDA-MB-361 tumor-bearing mice as well as the anti-brain metastasis in tail vein injection mice model were also investigated. Our results showed that actein inhibited HER2-positive breast cancer cells viability, proliferation and migration. Actein also induced MDA-MB-361 cells G1 phase arrest and inhibited the expressions of cyclins and cyclin-dependent kinases. For intracellular mechanisms, actein inhibited the expressions of molecules in AKT/mTOR and Ras/Raf/MAPK signaling pathways. Furthermore, actein (15 mg/kg) was shown to exhibit anti-tumor and anti-metastatic activities in MDA-MB-361 breast tumor-bearing mice, and reduced brain metastasis in tail vein injection mice model. All these findings strongly suggested that actein is a potential anti-metastatic agent for HER2-positive breast cancer.

Actein inhibits cell proliferation and migration and promotes cell apoptosis in human non-small cell lung cancer cells.

Non-small cell lung cancer (NSCLC) is the leading cause of death in smokers and the most common cause for cancer mortality in both males and females in the United States. Predisposition of this malignancy to distant metastasis leads to poor prognosis; therefore, it is urgent to discover novel therapeutic agents for metastatic NSCLC. The present study aimed to investigate the effects of actein treatment on NSCLC cell growth and migration. Cell viability assays demonstrated that administration of actein markedly inhibited NSCLC cell proliferation in a dose- and time-dependent manner. Transwell assays demonstrated that actein treatment suppressed cell migration and invasion in two NSCLC cell lines, A549 and 95D. Furthermore, treatment with actein remarkably increased the activities of caspase-3 and -9 in NSCLC cells. The protein expression levels of cytoplasmic BCL2 apoptosis regulator (Bcl-2) and BCL2 associated X (Bax) were markedly decreased, while the protein expression levels of mitochondrial Bax, caspase-3, -9 and cytochrome c were upregulated following actein treatment, as evidenced by western blot analysis. The present results demonstrated that actein inhibited cell proliferation and metastasis and promoted cell apoptosis in NSCLC cells, which indicated that actein administration might serve as a potential therapeutic strategy for the treatment of NSCLC in the clinic.

A transcriptomic analysis of black cohosh: Actein alters cholesterol biosynthesis pathways and synergizes with simvastatin.

Previous studies indicate that the herb black cohosh (Actaea racemosa L.) and the triterpene glycoside actein inhibit the growth of human breast cancer cells and activate stress-associated responses. This study assessed the transcriptomic effects of black cohosh and actein on rat liver tissue, using Ingenuity and ToxFX analyses. Sprague-Dawley rats were treated with an extract of black cohosh enriched in triterpene glycosides (27%) for 24 h or actein for 6 and 24 h, at 35.7 mg/kg, and liver tissue collected for gene expression analysis. Ingenuity analysis indicates the top canonical pathways are, for black cohosh, RAR Activation, and, for actein, Superpathway of Cholesterol Biosynthesis, at 24 h. Actein alters the expression of cholesterol biosynthetic genes, but does not inhibit HMG-CoA reductase activity. Black cohosh and actein inhibited the growth of human breast and colon cancer cells and synergized with the statin simvastatin. Combinations of black cohosh with certain classes of statins could enhance their activity, as well as toxic, such as inflammatory liver, side effects. Transcriptomic analysis indicates black cohosh and actein warrant further study to prevent and treat cancer and lipid disorders. This study lays the basis for an approach to characterize the mode of action and toxicity of herbal medicines.

Actein Inhibits the Proliferation and Adhesion of Human Breast Cancer Cells and Suppresses Migration in vivo.

Background and purpose: Metastasis is an important cause of death in breast cancer patients. Anti-metastatic agents are urgently needed since standard chemotherapeutics cannot diminish the metastatic rate. Actein, a cycloartane triterpenoid, has been demonstrated to exhibit anti-angiogenic and anti-cancer activities. Its anti-metastatic activity and underlying mechanisms were evaluated in the present study. Methods: The effects of actein on the proliferation, cell cycle phase distribution, migration, motility and adhesion were evaluated using two human breast cancer cell lines, MDA-MB-231 (estrogen receptor-negative) and MCF-7 cells (estrogen receptor-positive) in vitro. Western blots and real-time PCR were employed to examine the protein and mRNA expression of relevant signaling pathways. A human metastatic breast cancer cell xenograft model was established in transparent zebrafish embryos to examine the anti-migration effect of actein in vivo. Results: In vitro results showed that actein treatment significantly decreased cell proliferation, migration and motility. Furthermore, actein significantly caused G1 phase cell cycle arrest and suppressed the protein expression of matrix metalloproteinases of MDA-MB-231 cells. In addition, actein inhibited breast cancer cell adhesion to collagen, also reduced the expression of integrins. Actein treatment down-regulated the protein expression of epidermal growth factor receptor (EGFR), AKT and NF-κB signaling proteins. In vivo results demonstrated that actein (60 µM) significantly decreased the number of zebrafish embryos with migrated cells by 74% and reduced the number of migrated cells in embryos. Conclusion: Actein exhibited anti-proliferative, anti-adhesion and anti-migration activities, with the underlying mechanisms involved the EGFR/AKT and NF-kappaB signalings. These findings shed light for the development of actein as novel anti-migration natural compound for advanced breast cancer.

Actein ameliorates hepatic steatosis and fibrosis in high fat diet-induced NAFLD by regulation of insulin and leptin resistant.

Insulin and leptin resistance are highly involved in metabolic syndrome and non-alcoholic fatty liver disease (NAFLD). Presently, no approved treatment is available. Actein is isolated from the rthizomes of Cimicifuga foetida, a triterpene glycoside, exhibiting important biological properties, such as anti-inflammatory, anti-cancer, and anti-oxidant activity. However, its effects on metabolic syndrome are poorly understood. The aims of the study were mainly to investigate the molecular mechanisms regulating insulin and leptin resistance, and lipogenic action of actein in high fat diet-fed mice. Our data indicated that actein-treated mice displayed lower body weight, epididymal and subcutaneous fat mass, as well as serum lipid levels. Also, improved insulin and leptin resistance were observed in actein-treated groups. Liver inflammation and fibrosis triggered by high fat diet were decreased for actein administration. Moreover, hepatic lipid accumulation was also reduced by actein along with reductions of hepatic de novo lipogenesis-linked signals in actein-treated rodents with high fat diet. High fat diet-induced activation of insulin receptor substrate 1/Forkhead box protein O1 (IRS1/FOXO1), Janus kinase 2 gene/signal transducer and activator of transcription (JAK2/STAT3) and Protein Kinase B/Glycogen synthase kinase 3 beta (AKT/GSK3ß) pathways in liver was inhibited by actein, a potential mechanism by which hyperinsulinemia, hyperleptindemia and dyslipidemia were attenuated. Thus, the findings above might be of nutritional and therapeutic importance for the treatment of NAFLD.

Actein inhibits glioma growth via a mitochondria-mediated pathway.

Previous studies indicate that the triterpene glycoside Actein from the herb black cohosh inhibits growth of human breast cancer cells. This study sought to investigate the effects of Actein on glioma cell growth and explore the potential mechanisms. Our results showed that administration of Actein significantly inhibited glioma cell viability in a dose- and time-dependent manner. Actein also increasingly inhibited the colony formation processes in glioma U87 cells and U251 cells. Administration of Actein also induced mitochondria-related apoptosis by increasing expression of pro-apoptotic factors Bax, cleaved caspase-3, cleaved caspase-9 and cleaved poly (ADP-ribose) polymerase 1 (PARP1) as well as decreasing anti-apoptotic Bcl-2 expression in U87 cells and U251 cells. In a xenograft model of glioma, Actein suppressed tumor growth and consistently induced cell apoptosis with the same mechanisms observed in vitro. In all, this study is the first report to address the growth inhibitory effects of Actein on glioma growth and propose that mitochondria-mediated apoptosis pathway may underlie the biological activities of Actein in glioma. Our study suggests that administration of Actein may serve as a potent therapeutic strategy for treatment of glioma.

Actein ameliorates hepatobiliary cancer through stemness and p53 signaling regulation.

Actein is isolated from the rthizomes of Cimicifuga foetida, which is a triterpene glycoside, displaying suppressive effects on breast cancer cells proliferation. However, the effects of actein treatment on liver injury, tending to cancer, have little to be known. Thus, the study is conducted to explore the role of actein in early liver cancer. Diethylnitrosamine (DEN) was used to induce liver cancer in mice followed by actein treatment at different concentrations. DEN caused steatohepatitis supported by fibrosis and inflammation, which were ameliorated for actein administration. Liver histology of mice with DEN treatment displayed hepatobiliary cysts, reversed by actein. Cell proliferation markers of Cyclin Ds and p53, as well as cancer stem cell markers of CD133 were highly increased in liver tissue samples from DEN-induced mice, and actein showed inhibitory role in these signals expression. Actein-reduced up-regulation of Hif-1α and VEGFR1 in DEN-stimulated liver tissue of mice was seen. Taken together, DEN promoted liver cancer progression, which was ameliorated by actein, supplying a potential therapeutic strategy for liver cancer in future.

Iron oxide magnetic nanoparticles combined with actein suppress non-small-cell lung cancer growth in a p53-dependent manner.

Actein (AT) is a triterpene glycoside isolated from the rhizomes of Cimicifuga foetida that has been investigated for its antitumor effects. AT treatment leads to apoptosis in various cell types, including breast cancer cells, by regulating different signaling pathways. Iron oxide (Fe3O4) magnetic nanoparticles (MNPs) are nanomaterials with biocompatible activity and low toxicity. In the present study, the possible benefits of AT in combination with MNPs on non-small-cell lung cancer (NSCLC) were explored in in vitro and in vivo studies. AT-MNP treatment contributed to apoptosis in NSCLC cells, as evidenced by activation of the caspase 3-signaling pathway, which was accompanied by downregulation of the antiapoptotic proteins Bcl2 and BclXL, and upregulation of the proapoptotic signals Bax and Bad. The death receptors of TRAIL were also elevated following AT-MNP treatment in a p53-dependent manner. Furthermore, a mouse xenograft model in vivo revealed that AT-MNP treatment exhibited no toxicity and suppressed NSCLC growth compared to either AT or MNP monotherapies. In conclusion, this study suggests a novel therapy to induce apoptosis in suppressing NSCLC growth in a p53-dependent manner by combining AT with Fe3O4 MNPs.

Actein induces autophagy and apoptosis in human bladder cancer by potentiating ROS/JNK and inhibiting AKT pathways.

Human bladder cancer is a common genitourinary malignant cancer worldwide. However, new therapeutic strategies are required to overcome its stagnated survival rate. Triterpene glycoside Actein (ACT), extracted from the herb black cohosh, suppresses the growth of human breast cancer cells. Our study attempted to explore the role of ACT in human bladder cancer cell growth and to reveal the underlying molecular mechanisms. We found that ACT significantly impeded the bladder cancer cell proliferation via induction of G2/M cycle arrest. Additionally, ACT administration triggered autophagy and apoptosis in bladder cancer cells, proved by the autophagosome formation, LC3B-II accumulation, improved cleavage of Caspases/poly (ADP-ribose) polymerase (PARP). Furthermore, reduction of reactive oxygen species (ROS) and p-c-Jun N-terminal kinase (JNK) could markedly reverse ACT-induced autophagy and apoptosis. In contrast, AKT and mammalian target of rapamycin (mTOR) were greatly de-phosphorylated by ACT, while suppressing AKT and mTOR activity could enhance the effects of ACT on apoptosis and autophagy induction. In vivo, ACT reduced the tumor growth with little toxicity. Taken together, our findings indicated that ACT suppressed cell proliferation, induced autophagy and apoptosis through promoting ROS/JNK activation, and blunting AKT pathway in human bladder cancer, which indicated that ACT might be an effective candidate against human bladder cancer in future.