Search

Pancreatic cancer is the seventh leading cause of cancer-related death worldwide and is known as "the king of cancers". Currently, gemcitabine (GEM) as the clinical drug of choice for chemotherapy of advanced pancreatic cancer has poor drug sensitivity and ineffective chemotherapy. Nardoguaianone L (G-6) is a novel guaiane-type sesquiterpenoid isolated from

One new flavanonol 4 H-​1-​benzopyran-​4-​one,2-​(4-​hydroxyphenyl)​-​3,​7-​dihydroxy-​5-​methoxy-​8-​[5-​methyl-​2-​(1-​methylethenyl)​-​4-​hexenyl]​(21), and twenty-six known compounds 1–20, 22–2...

Psoralidin (PSO) is a natural coumarin isolated from the seeds of Psoralea corylifolia Linn. Previous studies have reported that PSO exerts numerous pharmacological bioactivities including antitumor. The present study aimed to investigate its anticancer effect using colon cancer cells. Cultured HT-29 and HCT-116 colon cancer cells were treated with different concentrations of PSO, and the cell viability, the intracellular reactive oxygen species (ROS), the protein expression, and the apoptosis were determined by MTT assay, DCFH

Colorectal cancer (CRC) is one of the most common causes of cancer-related death worldwide. Nannocystin ax (NAN), a 21-membered cyclodepsipeptide initially isolated from myxobacteria of the Nannocystis genus, was found to target the eukaryotic elongation factor 1A (eEF1A). The current study was designed to evaluate the anticancer effect and underlying mechanisms of NAN with in vitro and in vivo models. Results showed that NAN induced G1 phase cell cycle arrest and caspase-independent apoptosis in HCT116 and HT29 human CRC cells. NAN significantly downregulated cyclin D1 level in a short time, but NAN did not affect the transcription level and ubiquitin-dependent degradation of cyclin D1. Furthermore, NAN treatment directly targeted eEF1A and partially decreased the synthesis of new proteins, contributing to the downregulation of cyclin D1. Besides, NAN significantly suppressed tumor growth in the zebrafish xenograft model. In conclusion, NAN triggered G1 phase cell cycle arrest through cyclin D1 downregulation and eEF1A-targeted translation inhibition and promoted caspase-independent apoptosis in CRC cells.

Aims: Most chemotherapeutic agents exploit apoptotic signaling to trigger cancer cell death, which frequently results in drug resistance. Necroptosis, a nonapoptotic form of regulated cell death, offers an alternative strategy to eradicate apoptosis-resistant cancer cells. We previously reported a natural necroptosis inducer 2-methoxy-6-acetyl-7-methyljuglone (MAM) in A549 lung cancer cells. The current study is designed to investigate the detailed necroptotic signaling and its cytotoxicity on drug-resistant cancer cells. Furthermore, in vivo anticancer effects were also evaluated in nude mice model. Results: MAM directly targets receptor-interacting protein 1 (RIP1) kinase in A549 and H1299 cells, which is responsible for reactive oxygen species (ROS, mainly hydrogen peroxide) generation. A positive feedback loop between calcium (Ca2+) and c-Jun N-terminal kinase (JNK) occurred following ROS generation, leading to lysosomal membrane permeabilization and mitochondrial dysfunction. MAM showed similar cytotoxic potency toward cisplatin-resistant A549 (A549/Cis) cells by inducing necroptosis as confirmed by the protective effect of 7-Cl-O-Nec-1 (Nec-1s) and by the morphological characteristics obtained via transmission electron microscopy. Interestingly, tumor necrosis factor alpha (TNFα) was not involved in this process. Intraperitoneal injection of MAM significantly suppressed tumor growth in A549 tumor xenograft without significant body weight loss and multiorgan toxicities. Innovation and Conclusion: Our findings demonstrate that MAM induces necroptosis in A549 and H1299 lung cancer cells by targeting RIP1 kinase and ROS in a TNFα-independent manner. MAM kills A549/Cis cells with similar potency through induction of necroptosis. MAM shows anticancer effect in animal model. The present study raises the therapeutic possibility and strategy to combat cancer by the induction of necroptosis.

Background: As one of the effective pharmacological constituents of Ginseng Radix et Rhizoma, ginsenoside Rh2 (Rh2) exerts a remarkable anticancer effect on various cancer cell lines in vitro and strongly inhibits tumor growth in vivo without severe toxicity. Objective: This article reviewed existing evidence supporting the anticancer effects of Rh2 to classify and conclude previous and current knowledge on the mechanisms and therapeutic effects of Rh2, as well as to promote the clinical application of this natural product. Conclusion: This article reviewed the anticancer efficacies and mechanisms of Rh2, including the induction of cell cycle arrest and programmed cell death, repression of metastasis, alleviation of drug resistance, and regulation of the immune system. Finally, this paper discussed the research and application prospects of Rh2.

We report a novel and easy-to-fabricate polynuclear nanoparticle based on the collaborative re-assembly of nanoparticles as a robust chemogene co-delivery platform. Specifically, the polynuclear nanoparticle carrying DOX and siBcl-2 exerts remarkable co-delivery efficiency, increases tumour cell apoptosis and inhibits tumour cell proliferation in vitro and in vivo.

Baicalein (BA), one of the major bioactive flavonoids isolated from Scutellariae Radix, possesses various pharmacological activities. The present study aimed to investigate the protective effects of BA on tert‑butyl hydroperoxide (t‑BHP)‑induced hepatotoxicity, and to investigate the potential mechanisms in LO2 cells. BA was demonstrated to possess protective properties against t‑BHP injury in LO2 cells, as evidenced by MTT and lactate dehydrogenase assays. BA significantly prevented t‑BHP‑induced depolarization of mitochondrial membrane potential (MMP), decreased the percentage of apoptotic cells caused by t‑BHP, and prevented intracellular reactive oxygen species (ROS) generation in LO2 cells. Furthermore, BA slightly triggered autophagy in LO2 cells, as evidenced by the elevation of LC3‑II expression, while BA combined treatment with an autophagy inhibitor (chloroquine) or activator (rapamycin) did not alter the hepatoprotective properties. In conclusion, BA may possess a hepatoprotective effect against t‑BHP‑induced liver cell injury, dependent on ROS removal. Therefore, BA may represent a potential drug candidate in protecting hepatotoxicity.

Chelerythrine (CHE), a natural benzo[c]phenanthridine alkaloid, shows anti-cancer effect through a number of mechanisms. Herein, the effect and mechanism of the CHE-induced autophagy, a type II programmed cell death, in non-small cell lung cancer (NSCLC) cells were studied for the first time. CHE induced cell viability decrease, colony formation inhibition, and apoptosis in a concentration-dependent manner in NSCLC A549 and NCI-H1299 cells. In addition, CHE triggered the expression of phosphatidylethanolamine-modified microtubule-associated protein light-chain 3 (LC3-II). The CHE-induced expression of LC3-II was further increased in the combination treatment with chloroquine (CQ), an autophagy inhibitor, and large amounts of red-puncta were observed in the CHE-treated A549 cells with stable expression of mRFP-EGFP-LC3, indicating that CHE induces autophagy flux. Silence of beclin 1 reversed the CHE-induced expression of LC3-II. Inhibition of autophagy remarkably reversed the CHE-induced cell viability decrease and apoptosis in NCI-H1299 cells but not in A549 cells. Furthermore, CHE triggered reactive oxygen species (ROS) generation in both cell lines. A decreased level of ROS through pretreatment with N-acetyl-L-cysteine reversed the CHE-induced cell viability decrease, apoptosis, and autophagy. Taken together, CHE induced distinctive autophagy in A549 (accompanied autophagy) and NCI-H1299 (pro-death autophagy) cells and a decreased level of ROS reversed the effect of CHE in NSCLC cells in terms of cell viability, apoptosis, and autophagy., Highlights • Chelerythrine induces autophagic flux in non-small cell lung cancer (NSCLC) A549 and NCI-H1299 cells. • Chelerythrine induces an accompanied autophagy in A549 cells, while a pro-death autophagy in NCI-H1299 cells. • A decreased level of ROS reverses the chelerythrine-induced apoptosis and autophagy in NSCLC cells.

Recent discoveries revealed several types of programmed necrosis, such as necroptosis, ferroptosis, pyroptosis, etc. Necroptosis is mediated by signaling complexes with receptor-interacting protein kinases (RIPs) and mixed lineage kinase domain-like protein (MLKL). Here, we described an MLKL mediated non-canonical necroptosis through reactive oxygen species (ROS) in lung cancer cells triggered by a natural compound, tanshinol A (TSA). Morphologically, TSA-induced necrotic cell death is characterized by increased cell volume, transparent of cytoplasm, and rupture of the cell membrane. Biochemically, it induces intracellular ATP depletion and PI penetration. Molecularly, TSA-induced cell death is mediated by MLKL but independent of RIP1 and RIP3. Furthermore, TSA induces MLKL phosphorylation and membrane translocation, and cytosolic calcium accumulation. However, calcium shows no effect on TSA-induced cell death. Especially, TSA induces intracellular ROS generation, which was found to be the upstream of MLKL. Collectively, our data indicated that TSA triggers a novel type of programmed necrosis mediated by MLKL in lung cancer cells, which might have therapeutic potentials for lung cancer treatment.

Isobavachalcone (IBC), a naturally occurring chalcone, is mainly isolated from the seeds of Psoralea corylifolia Linn. IBC demonstrates multiple pharmacological activities, including anti-cancer, anti-microbial, anti-inflammatory, antioxidative, neuroprotective, and among others. Several potential targets of IBC, such as AKT, dihydroorotate dehydrogenase (DHODH), have been identified. The pharmacokinetic profiles of IBC have been reported as well. In this review, the pharmacological activities, the underlying mechanisms, the potential targets, and the pharmacokinetic profiles of IBC were summarized. IBC might be a promising lead compound for drug discovery.

Background Programmed death-ligand 1 (PD-L1), which can be induced by interferon-gamma (IFN-γ) in the tumor microenvironment, is a critical immune checkpoint in cancer immunotherapy. Natural products which reduce IFN-γ-induced PD-L1 might be exert immunotherapy effect. Licochalcone A (LCA), a natural compound derived from the root of Glycyrrhiza inflata Batalin. (Fabaceae), was found to interfere IFN-γ-induced PD-L1. Purpose The aim of this study is to further clarify the effect and the mechanism of LCA on inhibiting IFN-γ-induced PD-L1 in lung cancer cells. Methods The expression levels of PD-L1 were evaluated by flow cytometry, western blot and qRT-PCR. Click-iT protein synthesis assay and luciferase assay were used to identify the effect of LCA on protein synthesis. Jurkat T cell proliferation and apoptosis in the co-culture system were detected by flow cytometry. Flow cytometry was also applied to evaluate reactive oxygen species (ROS) generation. Results LCA downregulated IFN-γ-induced PD-L1 protein expression and membrane localization in human lung cancer cells, regardless of inhibiting PD-L1 mRNA level or promoting its protein degradation. LCA decreased apoptosis and proliferative inhibition of Jurkat T cells caused by IFN-γ-induced PD-L1-expressing in A549 cells in the co-culture system. Strikingly, LCA was verified as a protein synthesis inhibitor, which reduced both cap-dependent and -independent translation. LCA inhibited PD-L1 translation, likely due to inhibition of 4EBP1 phosphorylation (Ser 65) and activation of PERK-eIF2α pathway. Furthermore, LCA induced ROS generation in a time-dependent manner in lung cancer cells. N-acetyl-L-cysteine (NAC) not only revered ROS generation triggered by LCA but also restored IFN-γ-induced expression of PD-L1. Both the inhibition of 4EBP1 phosphorylation (Ser 65) and activation of PERK-eIF2α axis triggered by LCA was restored by co-treatment with NAC. Conclusion LCA abrogated IFN-γ-induced PD-L1 expression via ROS generation to abolish the protein translation, indicating that LCA has the potential to be applied in cancer immunotherapy.

Background Ovarian cancer is the first leading cause of death among gynecologic malignancies worldwide. Discovery of new chemotherapeutic drugs is still imperative for the improvement of the survival rate. Purpose This study aims to investigate the anti-cancer potential of alisol B 23-acetate (AB23), a protostane-type triterpene isolated from the Alismatis Rhizoma , in the parental and paclitaxel-resistant ovarian cancer cells. Methods MTT assay was performed to evaluate cell viability after treatment with AB23, along with flow cytometry for apoptosis and cell cycle analysis. Western blotting was conducted to determine the relative protein level. Wound healing and transwell assays were performed to investigate the effect of AB23 on cell migration and invasion. Results AB23 obviously inhibited proliferation of the three ovarian cancer cell lines, down-regulated the protein levels of CDK4, CDK6, and cyclin D1, and blocked the cell cycle progressions in G1 phase. Meanwhile, AB23 induced accumulation of the sub-G1 phase in the three cell lines in a concentration dependent manner. The protein levels of cleaved poly ADP-ribose polymerase (PARP) and the ratio of Bax/Bcl-2 were up-regulated after treatment with AB23. Further study showed that AB23 induced endoplasmic reticulum stress through IRE1 signaling pathway and silencing of IRE1 α partially enhanced AB23-induced apoptosis. Wound healing and transwell assays showed that AB23 could also suppress the migration and invasion of HEY cells. Moreover, it down-regulated the protein levels of matrix metalloproteinases MMP-2 and MMP-9. Conclusion AB23 possessed anti-proliferation, anti-migration and anti-invasion activities as a single agent on ovarian cancer cells.

Cucurbitacin E (CuE) is a triterpenoid with potent anticancer activities while the underlying mechanisms remain elusive. In the present study, the anticancer effects of CuE on 95D lung cancer cells were investigated. CuE decreased cell viability, inhibited colony formation, and increased reactive oxygen species (ROS) in a concentration-dependent manner, which were reversed by N-acetyl-l-cysteine (NAC). CuE induced apoptosis as determined by JC-1 staining, expression of Bcl-2 family proteins, cleavage of caspases, and TUNEL staining. NAC and Ac-DEVD-CHO partially reversed CuE-induced cleavage of caspase-3, caspase-7, and PARP. Furthermore, CuE caused accumulation of autophagic vacuoles and concentration- and time-dependent expression of LC3II protein. Autophagy inhibitors chloroquine and bafilomycin A1 enhanced CuE-induced LC3II expression and cell death. CuE-triggered protein expression of p-AKT, p-mTOR, Beclin-1, and p-ULK1 was partially reversed by NAC pretreatment. In addition, CuE treatment damaged F-actin without affecting β-tubulin as confirmed by immunofluorescence. In conclusion, CuE induced ROS-dependent apoptosis through Bcl-2 family and caspases in 95D lung cancer cells. Furthermore, CuE induced protective autophagy mediated by ROS through AKT/mTOR pathway. This study provides novel roles of ROS in the anticancer effect of CuE.

Redox signaling plays a fundamental role in maintaining cell physiological activities. A deregulation of this balance through oxidative stress or nitrosative stress has been implicated in cancer. Here, we reported that 2-methoxy-6-acetyl-7-methyl juglone (MAM), a natural naphthoquinone isolated from Polygonum cuspidatum Sieb. et Zucc, caused hydrogen peroxide (H2O2) dependent activation of JNK and induced the expression of inducible nitric oxide synthase (iNOS), thereby leading to nitric oxide (NO) generation in multiple cancer cells. Nitrosative stress induced necroptosis in A549 lung cancer cells, but resulted in caspase-dependent intrinsic apoptosis in B16-F10 melanoma and MCF7 breast cancer cells. In addition, a decrease in GSH/GSSG levels accompanied with increased ROS production was observed. Reversal of ROS generation and cell death in GSH pretreated cells indicated the involvement of GSH depletion in MAM mediated cytotoxicity. In summary, a natural product MAM induced NO-dependent multiple forms of cell death in cancer cells mediated by H2O2-dependent JNK activation in cancer cells. GSH depletion might play an initial role in MAM-induced cytotoxicity.

Ethanol is a common risk factor for liver injury. Cucurbitacin B (CuB) is a natural product with potent cytotoxic activities mediated by inducing apoptosis. This study investigated the effect of ethanol on CuB-induced cytotoxicity in LO2 hepatocytes. Low concentration of ethanol alone showed no significant cytotoxic effect on LO2 cells. CuB dose-dependently decreased cell viability. However, ethanol co-treatment significantly enhanced CuB-induced cytotoxicity. CuB-induced mitochondria membrane potential (ΔΨ) depolarization was further decreased by ethanol. Furthermore, CuB-induced apoptosis was augmented by ethanol, as evidenced by DNA fragmentation, Annexin V staining, and apoptotic protein expression. Ethanol inhibited CuB-induced autophagy, as determined by MDC staining, autophagic protein expression, and transmission electron microscopy. Therefore, the present data suggested that ethanol enhanced CuB cytotoxicity in LO2 hepatocytes, which was mediated by inhibiting autophagy and augmenting apoptosis.

Inactivation of the p53 transcription factor by mutation or other mechanisms is a frequent event in tumorigenesis. One of the major endogenous negative regulators of p53 in humans is hDM2, a ubiquitin E3 ligase that binds to p53 causing proteasomal p53 degradation. In this work, a library of organometallic iridium(III) compounds were synthesized and evaluated for their ability to disrupt the p53/hDM2 protein-protein interaction. The novel cyclometallated iridium(III) compound 1 [Ir(eppy)2(dcphen)](PF6) (where eppy = 2-(4-ethylphenyl)pyridine and dcphen = 4, 7-dichloro-1, 10-phenanthroline) blocked the interaction of p53/hDM2 in human amelanotic melanoma cells. Finally, 1 exhibited anti-proliferative activity and induced apoptosis in cancer cell lines consistent with inhibition of the p53/hDM2 interaction. Compound 1 represents the first reported organometallic p53/hDM2 protein-protein interaction inhibitor.

Glycerrhetinic acid (GA), one of the main bioactive constituents of Glycyrrhiza uralensis Fisch, exerts anti-cancer effects on various cancer cells. We confirmed that GA inhibited cell proliferation and induced apoptosis in non-small cell lung cancer A549 and NCI-H1299 cells. GA also induced expression of autophagy marker phosphatidylethanolamine-modified microtubule-associated protein light-chain 3 (LC3-II) and punta formation of green fluorescent protein microtubule-associated protein light-chain 3. We further proved that expression of GA-increased autophagy marker was attributed to activation instead of suppression of autophagic flux. The c-jun N-terminal kinase (JNK) pathway was activated after incubation with GA. Pretreatment with the JNK inhibitor SP600125 or silencing of the JNK pathway by siRNA of JNK or c-jun decreased GA-induced autophagy. The endoplasmic reticulum (ER) stress responses were also apparently stimulated by GA by triggering the inositol-requiring enzyme 1α (IRE1α) pathway. The GA-induced JNK pathway activation and autophagy were decreased by IRE1α knockdown, and inhibition of autophagy or the JNK cascade increased GA-stimulated IRE1α expression. In addition, GA-induced cell proliferative inhibition and apoptosis were increased by inhibition of autophagy or the JNK pathway. Our study was the first to demonstrate that GA induces cytoprotective autophagy in non-small cell lung cancer cells by activating the IRE1α-JNK/c-jun pathway. The combined treatment of autophagy inhibitors markedly enhances the anti-neoplasmic activity of GA. Such combination shows potential as a strategy for GA or GA-contained prescriptions in cancer therapy.

Cell death plays a critical role in organism development and the pathogenesis of diseases. Necrosis is considered a non-programmed cell death in an extreme environment. Recent advances have provided solid evidence that necrosis could be programmed and quite a few types of programmed necrosis, such as necroptosis, ferroptosis, pyroptosis, paraptosis, mitochondrial permeability transition-driven necrosis, and oncosis, have been identified. The specific biomarkers, detailed signaling, and precise pathophysiological importance of programmed necrosis are yet to be clarified, but these forms of necrosis provide novel strategies for the treatment of various diseases, including cancer. Natural compounds are a unique source of lead compounds for the discovery of anti-cancer drugs. Natural compounds can induce both apoptosis and programmed necrosis. In this review, we summarized the recent progress of programmed necrosis and introduced their natural inducers. Noptosis, which is a novel type of programmed necrosis that is strictly dependent on NAD(P)H: quinone oxidoreductase 1-derived oxidative stress was proposed. Furthermore, the anti-cancer strategies that take advantage of programmed necrosis and the main concerns from the scientific community in this regard were discussed.

The mammalian target of rapamycin (mTOR) pathway converges diverse environmental cues to support the lung cancer growth and survival. However, the mTOR-targeted mono-therapy does not achieve expected therapeutic effect. Here, we revealed that fangchinoline (FCL), an active alkaloid that purified from the traditional Chinese medicine Stephania tetrandra S. Moore, enhanced the anti-lung cancer effect of mTOR inhibitor everolimus (EVE). The combination of EVE and FCL was effective to activate Notch 3, and subsequently evoked its downstream target c-MYC. The blockage of Notch 3 signal by the molecular inhibitor of γ-secretase or siRNA of Notch 3 reduced the c-MYC expression and attenuated the combinational efficacy of EVE and FCL on cell apoptosis and proliferation. Moreover, the c-MYC could bind to the C/EBP homologous protein (CHOP) promoter and facilitate CHOP transcription. The conditional genetic deletion of CHOP reduced the apoptosis on lung cancer cells to the same degree as blockage of Notch 3/c-MYC axis, providing further evidence for that the Notch 3/c-MYC axis regulates the transcription of CHOP and finally induces apoptosis upon co-treatment of FCL and EVE in lung cancer cells. Overall, our findings, to the best of our knowledge, firstly link CHOP to Notch 3/c-MYC axis-dependent apoptosis and provide the Notch 3/c-MYC/CHOP activation as a promising strategy for mTOR-targeted combination therapy in lung cancer treatment.

The pseudokinase mixed lineage kinase domain-like protein (MLKL) is a core effector of necroptosis, and its function in necroptosis is widely studied. However, the function of MLKL in apoptosis remains unclear. In the present study, the role of MLKL in chelerythrine (CHE)-promoted apoptosis was studied. A special band of MLKL (i.e., *MLKL) was observed after treatment with CHE. MLKL and *MLKL were accumulated in the nucleus upon treatment with CHE and MLKL silencing reversed the CHE-induced apoptosis. Blockade of CHE-triggered reactive oxygen species (ROS) generation or inhibition of CHE-activated protein kinase-like endoplasmic reticulum kinase (PERK)-eukaryotic initiation factor 2 α subunit (eIF2α) pathway reversed the apoptosis. A decreased ROS level inhibited CHE-mediated nuclear translocation of MLKL and *MLKL and the activation of eIF2α, whereas MLKL or eIF2α silencing did not affect the CHE-triggered ROS generation. Furthermore, MLKL silencing prevented the CHE-activated eIF2α signal, and eIF2α silencing blocked the CHE-induced nuclear translocation of MLKL and *MLKL. Our studies suggested that CHE possibly induces apoptosis through the nuclear translocation of MLKL and *MLKL, which is promoted by a mutual regulation between MLKL and PERK-eIF2α pathway in response to ROS formation. The present study clarified the new function of MLKL in apoptosis.

Doxorubicin (DOX) is a widely used antineoplastic agent in clinics. However, its clinical application is largely limited by its cardiotoxicity. Diethyl blechnic (DB) is a novel compound isolated from Salvia miltiorrhiza Bunge. Here, we study the effect of DB on DOX-induced cardiotoxicity and its underlying mechanisms. Cellular viability was tested by 3-[-4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) and protein level was evaluated by Western blotting. 5,5’,6,6’-tetrachloro-1,1’,3,3’-tetraethylbenzimidazolylcarbocyanine iodide (JC-1) staining was performed to determine the mitochondrial membrane potential (MMP). Hoechst 33342 staining and TUNEL staining was performed to test the apoptosis. Reactive oxygen species (ROS) generation was investigated by using flow cytometry. DB significantly inhibited DOX-induced apoptosis in H9c2 cells and primary cultured cardiomyocytes. Moreover, DB decreased cell apoptotic morphological changes and reversed the mitochondrial membrane potential induced by DOX. Meanwhile, pre-treatment with DB increased the expression levels of B-cell lymphoma 2 (Bcl-2), B-cell lymphoma-extra-large (Bcl-xl), and survivin and reduced the expression levels of Bcl-2-associated X protein (Bax), p-p53, cytochrome c (cyt c), and cleaved-caspase 3, 7, 8, 9 in the protein levels in DOX-treated H9c2 cells. Furthermore, DB suppressed ROS generation. The DB-mediated protective effects were accompanied by increased c-Jun N-terminal kinase1/2 (JNK1/2) expression. In addition, SP600125, the inhibitor of JNK1/2, abolished the protective effect of DB. We concluded that DB protected cardiomyocytes against DOX-induced cytotoxicity by inhibiting ROS and activating the JNK1/2 pathway. Therefore, DB is a promising candidate as a cardioprotective agent against DOX-induced cardiotoxicity.

Non-small cell lung cancer (NSCLC) is one of the most common forms and leading causes of cancer-related mortality worldwide, and discovery of new effective drugs still remains imperative to improve the survival rate. Nagilactone E (NLE) is a natural product isolated from Podocarpus nagi seeds, which has been used as raw materials for edible oil and industrial oil extraction. This study aimed to investigate the anticancer potential of NLE against NSCLC A549 and NCI-H1975 cells. MTT assay revealed that NLE inhibited the proliferation of A549 and NCI-H1975 cells with IC50s of 5.18 ± 0.49 and 3.57 ± 0.29 μM, respectively. NLE treatment inhibited clone formation in both cancer cell lines. Cell cycle analysis indicated that NLE treatment effectively induced G2 phase cell cycle arrest in A549 and NCI-H1975 cells. NLE downregulated the phosphorylation of cdc2 (Tyr15) and cdc25C (Ser216) as well as the expression level of the protein kinase Wee1 in concentration- and time-dependent manners. In addition, NLE treatment decreased the protein level of Cyclin B1 as well as its nuclear localization, which might decrease the activity of the Cyclin B1/cdc2 complex and induce G2 phase arrest. Long-term NLE treatment also induced caspase-dependent cell apoptosis, as evidenced by increase in Annexin V positive cells and the cleavage of PARP. To sum, NLE inhibited proliferation, induced G2 phase arrest, and triggered caspase-dependent apoptosis in NSCLC cells, suggesting it to be a potential leading compound for cancer treatment.

Platycodin D (PD), a triterpenoid saponin isolated from Platycodonis Radix, is a famous Chinese herbal medicine that has been shown to have anti-proliferative effects in several cancer cell lines. The aim of this study was to determine the changes in cellular proteins after the treatment of hepatocellular carcinoma HepG2 cells with PD using proteomics approaches. The cell viability was determined using the MTT assay. The proteome was analyzed by two-dimensional difference gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Western blot analysis was used to confirm the expression of changed proteins. Our results showed that PD inhibited the proliferation of HepG2 cells in concentration- and time-dependent manners. Sixteen proteins were identified to be up-regulated in PD-treated HepG2 cells, including ATP5H, OXCT1, KRT9, CCDC40, ERP29, RCN1, ZNF175, HNRNPH1, HSP27, PA2G4, PHB, BANF1, TPM3, ECH1, LGALS1, and MYL6. Three proteins (i.e., RPS12, EMG1, and KRT1) decreased in HepG2 cells after treatment with PD. The changes in HSP27 and PHB were further confirmed by Western blotting. In conclusion, our results shed new lights on the mechanisms of action for the anti-cancer activity of PD.

This study aimed to isolate terpenoids from Alisma orientalis (Sam.) Juzep. and elucidate their antiproliferative activities, as well as structure-activity relationships. Fourteen protostane-type triterpenoids were isolated from the rhizome of A. orientalis. Among these triterpenoids, alisol A (1), alisol A 24-acetate (2), alisol B (3), alisol B 23-acetate (4), and alisol G (8) presented inhibitory effects on cancer cell lines tested. Compounds 3 and 4 showed the highest potential; IC50 values for HepG2, MDA-MB-231, and MCF-7 cells were 16.28, 14.47, and 6.66 μM for 3 and 18.01, 15.97, and 13.56 μM for 4, respectively. Based on these results, we concluded that the degree of C-16 oxidation and the double bond between C-13 and C-17 may be significant in anti-proliferative activities. Further study showed that 3 and 4 effectively induced apoptosis, as confirmed by flow cytometry. Increased intracellular calcium concentration and endoplasmic reticulum stress were detected after treatment with 4 in HepG2 cells. Although compounds 1 and 2 induced minimal apoptosis, they evidently delayed the G2/M phase in HepG2 cells. Further study showed that 1-4 also enhanced LC3II expression, indicating autophagy is occured.

Glycyrrhetinic acid (GA), one of the main constituents of the famous Chinese medicinal herb and food additive licorice (Glycyrrhiza uralensis Fisch), has been indicated to possess potential anticancer effects and is widely utilized in hepatocellular carcinoma (HCC) targeted drug delivery systems (TDDS) due to the highly expressed target binding sites of GA on HCC cells. This study found that GA reduced the cell viability, increased the release of lactate dehydrogenase, and enhanced the expression of Bax, cleaved caspase-3, and LC3-II in HCC cells. The GA-triggered autophagy has been further confirmed by monodansylcadaverine staining as well as transmission electron microscopy analysis. The cell viability was obviously decreased whereas the expression of cleaved caspases was significantly increased when inhibition of autophagy by choloroquine or bafilomycin A1, suggesting that GA triggered a protective autophagy. Extracellular regulated protein kinase (ERK) was activated after treatment with GA in HepG2 cells and pretreatment with U0126 or PD98059, the MEK inhibitors, reversed GA-triggered autophagy as evidenced by decreased expression of LC3-II and formation of autophagosomes, respectively. Furthermore, GA-induced cell death and apoptosis were enhanced after pretreatment with PD98059. This is the first report that GA triggers a protective autophagy in HCC cells via activation of ERK, which might attenuate the anticancer effects of GA or chemotherapeutic drugs loaded with GA-modified TDDS.

Ovarian cancer remains the most lethal gynecological malignant tumor. In this study, 24 xanthones were isolated and identified from the pericarps of mangosteen (Garcinia mangostana), and their anti-proliferative activities were tested in ovarian cancer cells. Garcinone E (GE) was found to exhibit excellent anti-proliferative effects among the tested xanthones. It significantly inhibited the proliferation in HEY, A2780, and A2780/Taxol cells as evidenced by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, lactate dehydrogenase (LDH) release assay, Hoechst 33342 staining, annexin V/PI staining, and JC-1 staining. It induced endoplasmic reticulum (ER) stress and activated the protective inositol-requiring kinase (IRE)-1α pathway. Knocking down IRE-1α further activated the caspase cascade and caused an increase in cell death. Moreover, GE eliminated the migratory ability of HEY cells by reducing the expression of RhoA and Rac. It also blocked the invasion, which might be related to downregulation of matrix metalloproteinases (MMPs), i.e., MMP-9 and MMP-2, and upregulation of tissue inhibitors of metalloproteinase (TIMP) -1 and TIMP-2. In summary, GE exerts anticancer activities by inducing apoptosis and suppressing migration and invasion in ovarian cancer cells, which indicates its therapeutic potential for ovarian cancer.

We have developed mitochondria-targeted self-assembled nanoparticles (NPs) based on amphiphilic triphenylphosphine–quercetin (TPP–Que) conjugates, which were further modified by poly(ethylene glycol) via a pH-responsive coordination bond to form TQ-PEG NPs. And it is revealed that the TQ-PEG NPs were more effective therapeutic agents compared with Que in vitro and in vivo.

Inhibition of autophagy is a promising strategy for non-small cell lung cancer (NSCLC) treatment, which is in the clinical trials. However, only chloroquine is used in clinic as an autophagic inhibitor and the inhibitory effect of chloroquine on autophagy is finite. Therefore, the development of an alternative autophagic inhibitor for NSCLC therapy becomes necessary. In the present study, cepharanthine (CEP), an alkaloid extracted from Stephania cepharantha Hayata, was identified as a novel autophagic inhibitor in NSCLC cells. The potential mechanism of the CEP-inhibited autophagy was by blockage of autophagosome-lysosome fusion and inhibition of lysosomal cathepsin B and cathepsin D maturation. Furthermore, we found for the first time that dacomitinib (DAC), a second-generation epidermal growth factor receptor inhibitor that in the phase III clinical trials for NSCLC treatment, induced a protective autophagy to decrease its anti-cancer effect. Combined treatment with CEP increased the anti-proliferative and apoptotic effects of DAC in vitro and enhanced the anti-cancer effect of DAC in NCI-H1975 xenograft mice. Collectively, CEP might be further developed as an autophagic inhibitor, and combined treatment of CEP and DAC could offer an effective strategy for NSCLC treatment.

Heat shock protein 90 (Hsp90) is a critically conserved molecular chaperone protein and promising therapeutic target for cancer treatment. In this study, platycodin D (PD), a saponin isolated from traditional Chinese herb Platycodonis Radix, was identified as a novel Hsp90 inhibitor. We verified that PD did not affect the ATPase activity of Hsp90. However, PD disrupted the co-chaperone interaction of Hsp90/cell division cycle protein 37 (Cdc37) and subsequently degraded multiple Hsp90 client proteins without the feedback increase of Hsp70. In different genotypes of non-small cell lung cancer cells, co-treatment with the mTOR inhibitor Everolimus and PD enhanced antiproliferation activity and apoptotic effect. The feedback survival signal upon mTOR inhibition was fully terminated by the co-administration with PD through reduced epidermal growth factor receptor (EGFR) and insulin growth factor 1 receptor (IGF1R) expression, suppressed AKT activity, and reinforced 4E-BP1 inhibition. Our results not only identified PD as a novel Hsp90 inhibitor by disrupting the protein-protein interaction of Hsp90/Cdc37 complex, but also provided mechanistic insights into the ineffectiveness of mTOR inhibitors and identified therapeutic strategy for cancer treatment.

Cucurbitacin B (Cuc B) is a natural product with potent anti-cancer activities in solid tumors. We investigated the anti-cancer effect of Cuc B on K562 leukemia cells. Cuc B drastically decreased cell viability in a concentration-dependent manner. Cuc B treatment caused DNA damage, as shown by long tails in the comet assay and increased γH2AX protein expression. Immunofluorescence, Fluo3- AM, and JC-1 staining results showed that Cuc B treatment induced nuclear γH2AX foci, increased intracellular calcium ion concentration, and depolarized mitochondrial membrane potential (MMP), respectively. Cuc B induced G2/M phase arrest and apoptosis, as shown by flow cytometry, DNA fragmentation, and protein expression analyses. In addition, Cuc B dramatically increased intracellular reactive oxygen species (ROS) generation as measured by DCFH2-DA. N-acetyl-l-cysteine pretreatment significantly reversed Cuc B-induced DNA damage, increased intracellular calcium ion concentration, and reduced MMP, G2/M phase arrest, and apoptosis. Taken together, these results suggested that ROS mediated Cuc B-induced DNA damage, G2/M arrest, and apoptosis in K562 cells. This study provides novel mechanisms to better understand the underlying anti-cancer mechanisms of Cuc B.

AKT is the frequently overexpressed and constitutively active kinase within NSCLC cells and recognized as a promising target for NSCLC treatment. However, AKT inhibition relieves the feedback inhibition of upstream receptor tyrosine kinases (RTKs) that may weaken the efficiency of AKT inhibitors. Platycodin D (PD), isolated from widely-used traditional Chinese medicine Platycodonis Radix, is now found to remarkably enhance the anti-proliferative effect of AKT inhibitors. In this study, combinatorial activity of AKT inhibitor MK2206 and PD on cell proliferation, apoptosis and related signaling were disclosed. Long-term AKT inhibition induced up-regulation of RTKs, including EGFR and HER-2. Co-treatment of MK2206 with PD could abolish this feedback survival through decrease of EGFR, HER-2, and p-AKT, and profound inhibition of 4E-BP1, leading to an amplified anti-proliferative and apoptotic activity in NSCLC cells. Similarly, feedback activation in response to reduction of AKT expression by small interfering RNA (siRNA) was also blocked by PD and apoptotic effect was further enhanced. Thus, PD potentiated proliferative inhibition and apoptotic induction of both AKT inhibitor and siRNA. These findings also reveal the limitations of suppressing feedback-regulated pathways by monotherapy and establish a mechanistic rationale for a novel combination approach targeting AKT for the treatment of NSCLC.

Osimertinib (OSI), also known as AZD9291, is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that has been approved for the treatment of non-small cell lung cancer (NSCLC) patients harboring EGFR T790M mutation. Herein, we indicated for the first time that OSI increased the accumulations of cytoplasmic vacuoles, the expression of phosphatidylethanolamine-modified microtubule-associated protein light-chain 3 (LC3-II), and the formation of GFP-LC3 puncta in various cancer cells. The OSI-induced expression of LC3-II was further increased when combined treatment with chloroquine (CQ), an autophagy inhibitor, and the mRFP-EGFP-LC3 plasmid-transfected cells exposed to OSI led to the production of more red-fluorescent puncta than green-fluorescent puncta, indicating OSI induced autophagic flux in the NSCLC cells. Knockdown of EGFR showed no effect on the OSI-induced expression of LC3-II in NCI-H1975 cells. In addition, OSI increased reactive oxygen species (ROS) generation and scavenge of ROS via pretreatment with N-acetyl-l-cysteine (NAC), catalase (CAT), or vitamin E (Vita E) significantly inhibited OSI-induced the accumulations of cytoplasmic vacuoles, the expression of LC3-II, as well as the formation of GFP-LC3 puncta. Combinative treatment with CQ could not remarkably change the OSI-induced cell viability decrease, whereas the OSI-induced cell viability decrease and apoptosis could be reversed through pretreatment with NAC, CAT, and Vita E, respectively. Taken together, this is the first report that OSI induces an accompanied autophagy and the generation of ROS is critical for the OSI-induced autophagy, cell viability decrease, and apoptosis in NSCLC cells.

Solasodine, a steroidal alkaloid isolated from solanaceous species, exhibits anticancer activities on several cell lines. This study aimed to explore the antitumor potential of solasodine on ovarian cancer cells. The MTT assay, lactate dehydrogenase release assay, Hoechst 33342 staining, 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethyl-imidacarbocyanine staining assay, and Annexin V/PI assay were conducted to investigate the antiproliferation and apoptosis-inducing effects of solasodine. Monodansylcadaverine staining was performed to label the acidic puncta on ovarian cancer HEY cells. A wound healing assay and Transwell assay were carried out to determine whether solasodine elicits an antimetastatic effect on HEY cells. A gelatin zymography assay was applied to detect the enzymatic activities of matrix metalloproteinases. Western blot was employed to examine relevant protein expression. Results revealed that solasodine inhibited cell viabilities in a time- and dose-dependent manner, triggered apoptotic body formation, reduced cell mitochondrial membrane potential, and interfered with autolysosome degradation in ovarian cancer cells. Solasodine also suppressed the migration and invasion of HEY cells by downregulating matrix metalloproteinase expression and activities. This study could be used as a basis for further studies on the molecular mechanisms of the antiproliferation, apoptosis-inducing, autophagy-modifying, and antimetastatic activities of solasodine.

Background Panacis Japonici Rhizoma (PJR) is one of the most famous Chinese medical herbs that is known for exhibiting potential anti-cancer effects. Purpose This study aims to isolate and investigate the anti-cancer potential of saponins from PJR in ovarian cancer cells. Methods The compounds were separated by comprehensive chromatographic methods. By comparison of the 1H- and 13C NMR data, as well as the HR-ESI-MS data, with the corresponding references, the structures of compounds were determined. MTT assay was performed to evaluate cell viability, along with flow cytometry for cell cycle analysis. JC-1 staining, Annexin V-PI double staining as well as Hoechst 33; 342 staining were used for detecting cell apoptosis. Western blot analysis was conducted to determine the relative protein level. Transwell assays were performed to investigate the effect of the saponin on cell migration and invasion and zymography experiments were used to detect the enzymatic activities. Results Eleven saponins were isolated from PJR and their anti-proliferative effects were evaluated in human ovarian cancer cells. Chikusetsusaponin IVa methyl ester (1) exhibited the highest anti-proliferative potential among these isolates with the IC50 values at less than 10 µM in both ovarian cancer A2780 and HEY cell lines. Compound 1 induced G1 cell cycle arrest accompanied with an S phase decrease, and down-regulated the expression of cyclin D1, CDK2, and CDK6. Further study showed that compound 1 effectively decreased the cell mitochondrial membrane potential, increased the annexin V positive cells and nuclear chromatin condensation, as well as enhanced the expression of cleaved PARP, Bax and cleaved-caspase 3 while decreasing that of Bcl-2. Moreover, compound 1 suppressed the migration and invasion of HEY and A2780 cells, down-regulated the expression of Cdc42, Rac, RohA, MMP2 and MMP9, and decreased the enzymatic activities of MMP2 and MMP9. Conclusion These results provide a comprehensive evaluation of compound 1 as a potential agent for the treatment of ovarian cancer.

Licochalcone A (LCA), a flavonoid isolated from the famous Chinese medicinal herb Glycyrrhiza uralensis Fisch, presents obvious anti-cancer effects. In this study, the anti-cancer effects and potential mechanisms of LCA in non-small cell lung cancer (NSCLC) cells were studied. LCA decreased cell viability, increased lactate dehydrogenase release and induced apoptosis in a concentration-dependent manner in NSCLC cells while not in human embryonic lung fibroblast cells. The expression of phosphatidylethanolamine-modified microtubule-associated protein light-chain 3 (LC3-II) and formation of GFP-LC3 punta, two autophagic markers, were increased after treatment with LCA. LCA-induced LC3-II expression was increased when combined with chloroquine (CQ), while knock-down of autophagy related protein (ATG) 7 or ATG5 reversed LCA-induced LC3-II expression and GFP-LC3 punta formation, suggesting that LCA induced autophagy in NSCLC cells. Inhibition of autophagy could not reverse the LCA-induced cell viability decrease and apoptosis. In addition, LCA increased the expression of endoplasmic reticulum stress related proteins, such as binding immunoglobulin protein and C/EBP homologous protein (CHOP). Knock-down of CHOP reversed LCA-induced cell viability decrease, apoptosis and autophagy. Taken together, LCA-induced autophagic effect is an accompanied phenomenon in NSCLC cells and CHOP is critical for LCA-induced cell viability decrease, apoptosis and autophagy.

Signal transducer and activator of transcription 3 (STAT3) is a potential drug target for chemotherapy. Cryptotanshinone (CTS) was identified as a potent STAT3 inhibitor, while the effect of other tanshinones remains unknown. In this study, the influence of eight tanshinones on STAT3 activity was initially screened and isocryptotanshinone (ICTS) significantly inhibited STAT3 activity in a dual luciferase assay. ICTS inhibited the constitutive and inducible phosphorylation of STAT3 at Y705 without affecting the phosphorylation of STAT3 at S727 in A549 lung cancer cells. Furthermore, ICTS inhibited the nuclear translocation of STAT3. Compared with CTS, ICTS exhibited a stronger inhibitory effect on STAT3 phosphorylation and on A549 cytotoxicity. ICTS induced autophagy as evidenced by the accumulation of autophagic vacuoles and the increased expression of LC3 protein and autophagosomes. ICTS-induced cell death was partially reversed by the autophagy inhibitor chloroquine. The docking assay predicted that both ICTS and CTS bind the SH2 domain of STAT3. ICTS formed hydrogen bonds and pi-pi interaction with the nearby amino acid residues of Lys591, Arg609, and Ser636. These findings suggested that ICTS, a natural compound, is a potent STAT3 inhibitor. ICTS induced apoptosis and pro-death autophagy in A549 cells.

Combination therapy has been developed as a promising therapeutic approach for hepatocellular carcinoma therapy. Here we report a low toxicity and high performance nanoparticle system that was self-assembled from a poly(ethylenimine)-glycyrrhetinic acid (PEI-GA) amphiphilic copolymer as a versatile gene/drug dual delivery nanoplatform. PEI-GA was synthesized by chemical conjugation of hydrophobic GA moieties to the hydrophilic PEI backbone via an acylation reaction. The PEI-GA nanocarrier could encapsulate doxorubicin (DOX) efficiently with loading level about 12% and further condense DNA to form PEI-GA/DOX/DNA complexes to codeliver drug and gene. The diameter of the complexes is 102 ± 19 nm with zeta potential of 19.6 ± 0.2 mV. Furthermore, the complexes possess liver cancer targeting ability and could promote liver cancer HepG2 cell internalization. Apoptosis of cells could be induced by chemotherapy of DOX, and PI3K/Akt/mTOR signaling pathway acts a beneficial effect on the modulation of autophagy. Here, it is revealed that utilizing PEI-GA/DOX/shAkt1 complexes results in effective autophagy and apoptosis, which are useful to cause cell death. The induction of superfluous autophagy is reported to induce type-II cell death and also could increase the sensity of chemotherapy to tumor cells. In this case, combining autophagy and apoptosis is meaningful for oncotherapy. In this study, PEI-GA/DOX/shAkt1 has demonstrated favorable tumor target ability, little side effects, and ideal antitumor efficacy.

Background Psoralidin (PSO), a natural phenolic coumarin, was reported to have anti-cancer activities. PSO induced reactive oxygen species (ROS) generation in cancer cells. The role of ROS in its anti-cancer effect remains unclear. Purpose This study was designed to investigate the potential roles of ROS in PSO-induced anti-cancer effect in MCF-7 breast cancer cells. Methods Effect of PSO on cancer cell proliferation was determined by MTT assay. Comet assay was used to determine DNA damage. Protein expression was detected by Western blotting. Autophagic vacuoles were detected by monodansylcadaverine (MDC) staining. ROS generation was measured by fluorescent probe. NOX4 localization was determined by immunofluorescence staining. Results PSO treatment caused proliferation inhibition in time- and dose- dependent manners, which was partially reversed by N-acetyl cysteine (NAC) and diphenyleneiodonium (DPI). PSO induced DNA damage and increased protein expression of γ-H 2 AX, phosphorylation of ATM, ATR, Chk1, and Chk2. PSO induced autophagy as evidenced by the accumulation of autophagic vacuoles and alterations of autophagic protein expression. PSO-induced cell death was enhanced by autophagy inhibitor chloroquine (CQ). Furthermore, PSO treatment induced ROS formation, which was reversed by NAC or DPI pretreatment. The expression of NOX4 was significantly enhanced by PSO. Both NAC and DPI could reverse PSO-induced DNA damage and autophagic responses. In addition, silencing NOX4 by siRNA inhibited PSO-induced ROS generation, DNA damage, and autophagy. Conclusions Taken together, these results showed that PSO induced DNA damage and protective autophagy mediated by ROS generation in a NOX4-dependent manner in MCF-7 cells.

Cucurbitacin B (Cuc B), a natural product, induced both protective autophagy and DNA damage mediated by ROS while the detailed mechanisms remain unclear. This study explored the mechanism of Cuc B-induced DNA damage and autophagy. Cuc B decreased cell viability in concentration- and time-dependent manners. Cuc B caused long comet tails and increased expression of γ-H2AX, phosphorylation of ATM/ATR, and Chk1/Chk2. Cuc B induced autophagy as evidenced by monodansylcadaverine (MDC) staining, increased expression of LC3II, phosphorylated ULK1, and decreased expression of phosphorylated AKT, mTOR. Cuc B induced apoptosis mediated by Bcl-2 family proteins and caspase activation. Furthermore, Cuc B induced ROS formation, which was inhibited by N-acetyl-L-cysteine (NAC). NAC pretreatment dramatically reversed Cuc B-induced DNA damage, autophagy, and apoptosis. Cuc B-induced apoptosis was reversed by NAC but enhanced by 3-methyladenine (3-MA), chloroquine (CQ), and silencing phosphatase and tensin homolog (PTEN). 3-MA and CQ showed no effect on Cuc B-induced DNA damage. In addition, Cuc B increased PTEN phosphorylation and silence PTEN restored Cuc B-induced autophagic protein expressions without affecting DNA damage. In summary, Cuc B induced DNA damage, apoptosis, and protective autophagy mediated by ROS. PTEN activation in response to DNA damage bridged DNA damage and prosurvival autophagy.

Ganoderma lucidum (Fr.) Karst is a traditional Chinese herb that has been widely used for centuries to treat various diseases including cancer. Herein, an ethanol-soluble and acidic component (ESAC), which mainly contains triterpenes, was prepared from G. lucidum and its anti-tumor effects in vitro were tested on human breast cancer cells. Our results showed that ESAC reduced the cell viability of MCF-7 and MDA-MB-231 cells in a concentration-dependent manner with IC50 of about 100 μg/mL and 60 μg/mL, respectively. DNA damage was detected by Comet assay and the increased expression of γ-H2AX after ESAC treatment was determined in MCF-7 cells. Moreover, ESAC effectively mediated G1 cell cycle arrest in both concentration- and time-dependent manners and induced apoptosis as determined by Hoechst staining, DNA fragment assay and Western blot analysis in MCF-7 cells. In conclusion, ESAC exerts anti-proliferation effects by inducing DNA damage, G1 cell cycle arrest and apoptosis in human breast cancer cells.

Platycodin D, the main saponin isolated from Chinese herb Platycodonis Radix, exhibits anticancer activities against various cancer cell lines. Here we evaluated its anticancer action against human hepatocellular carcinoma cells in vitro and in vivo, and elucidated the relationship between platycodin D-induced apoptosis and autophagy.The viability of human hepatocellular carcinoma BEL-7402 cells was evaluated with MTT assay, and the apoptosis was examined using Annexin V/PI and Hoechst 33342 staining assays. Monodansylcadaverine (MDC) staining was used to label autophagic vacuoles. The proteins were detected using Western blot analysis. For studying its anticancer action in vivo, platycodin D (5 and 10 mg· kg(-1)·d(-1)) was intraperitoneally injected to BEL-7402-bearing mice for 21 days.Platycodin D (5-40 μmol/L) inhibited the cell proliferation in vitro with IC50 values of 37.70±3.99, 24.30±2.30 and 19.70±2.36 μmol/L at 24, 48 and 72 h, respectively. Platycodin D (5-20 μmol/L) dose-dependently increased BEL-7402 cell apoptosis, increased the Bax/Bcl-2 ratio and the levels of cleaved PARP and cleaved caspase-3, and decreased the level of Bcl-2. Furthermore, platycodin D (5-20 μmol/L) induced autophagy in BEL-7402 cells, as evidenced by formation of cytoplasmic vacuoles, increased amounts of LC3-II, and increased numbers of MDC-positive cells. Pretreatment with the autophagy inhibitor chloroquine (5 μmol/L) or BAF (50 nmol/L) significantly enhanced platycodin D-induced proliferation inhibition and apoptosis. Moreover, platycodin D (20 μmol/L) activated the ERK and JNK pathways in BEL-7402 cells, and simultaneous blockage of the two pathways effectively suppressed platycodin D-induced autophagy and enhanced platycodin D-induced apoptosis. In BEL-7402-bearing mice, platycodin D (10 mg·kg(-1)•d(-1)) significantly reduced relative tumor volume with decreased body weight.Platycodin D not only inhibits the proliferation of BEL-7402 cells but also suppresses BEL-7402 xenograft tumor growth. Platycodin D-induced cell proliferation inhibition and apoptosis are amplified by co-treatment with autophagy inhibitors.

Dihydroartemisinin (DHA), the main active metabolite of artemisinin derivatives, is among the artemisinin derivatives possessing potent anti-malarial and anti-cancer activities. In the present study, we found that DHA displayed significant anti-proliferative activity in human colorectal carcinoma HCT116 cells, which may be attributed to its induction of G1 phase arrest and apoptosis. To further elucidate the mechanism of action of DHA, a proteomic study employed two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was performed. Glucose-regulated protein 78 (GRP78), which is related with endoplasmic reticulum stress (ER stress), was identified to be significantly up-regulated after DHA treatment. Further study demonstrated that DHA enhanced expression of GRP78 as well as growth arrest and DNA-damage-inducible gene 153 (GADD153, another ER stress-associated molecule) at both mRNA and protein levels. DHA treatment also led to accumulation of GADD153 in cell nucleus. Moreover, pretreatment of HCT116 cells with the iron chelator deferoxamine mesylate salt (DFO) abrogated induction of GRP78 and GADD153 upon DHA treatment, indicating iron is required for DHA-induced ER stress. This result is consistent with the fact that the anti-proliferative activity of DHA is also mediated by iron. We thus suggest the unbalance of redox may result in DHA-induced ER stress, which may contribute, at least in part, to its anti-cancer activity.

Tanshinones are a group of bioactive constituents isolated from Salvia miltiorrhiza Bunge, a widely prescribed traditional Chinese herb. In the current study, the anticancer properties of total tanshinones (TDT) were evaluated using 95D lung cancer cells. Tanshinone IIA was identified as the main component of TDT. Compared with tanshinone IIA, TDT showed more cytotoxic effects on the 95D cells. Annexin V/7-AAD double staining, the depolarization of mitochondrial membrane potential (MMP) (Δψ), the up-regulation of pro-apoptotic proteins, such as cleaved-PARP, cleaved-caspase-3, Bax, and Bad, and the down-regulation of anti-apoptotic protein Bcl-2 were evidence of TDT-induced apoptosis. Furthermore, TDT-induced autophagy as demonstrated by monodansylcadaverine (MDC) staining and the up-regulation of autophagy-associated proteins, such as LC3-II, Beclin-1, Atg3, Atg5, Atg7, and Atg12. Autophagy inhibitors, 3-methyladenine (3-MA) and bafilomycin A1, enhanced TDT-induced cell death. 3-MA pretreatment enhanced the TDT-induced up-regulation of Bax and cleaved-PARP. In addition, TDT induced the generation of reactive oxygen species (ROS), which was reversed by N-acetylcysteine (NAC). NAC also reversed TDT-induced depolarization of Δψ, MDC staining, up-regulation of Bax, cleaved-PARP, Beclin-1, LC3-II, and cell viability. In conclusion, our findings showed that TDT-induced apoptosis and protective autophagy in 95D cells mediated by increasing intracellular ROS production.

Superparamagnetic iron oxide nanoparticle (SPION) holds great potential as a gene delivery system due to its unique properties, such as good biocompatibility and non-invasive targeting ability. In this study, we modified SPION with chitosan-graft-PEI (CHI-g-PEI) and PK11195, to fabricate a mitochondria-targeting gene carrier, PK-CP-SPION. PK-CP-SPION manifested prominent physicochemical properties for magnetic guided gene delivery, and it could effectively condense and protect DNA at proper weight ratios. The in vitro cytotoxicity of PK-CP-SPIONs was mild. Under an external magnetic field, the transfection efficiency of PK-CP-SPIONs was comparable to PEI 25 K with shorter transfection time. PK11195 facilitated the specific accumulation of PK-CP-SPIONs in mitochondria, leading to the leakage of cytochrome c, the dissipation of mitochondrial membrane potential and subsequently the activation of mitochondria apoptosis pathway. These results indicated that with further development, PK-CP-SPIONs could serve as a multifunctional nanoplatform for magnetic targeting gene delivery and mitochondria-targeting therapy, leading enhanced therapeutic effect towards tumor cells.

Purpose: Isocryptotanshinone (ICTS) is a natural bioactive product that is isolated from the roots of the widely used medical herb Salvia miltiorrhiza. However, few reports exist on the mechanisms underlying the therapeutic effects of ICTS. Here, we report that ICTS has anticancer activity and describe the mechanism underlying this effect. Methods: The antiproliferative effect of ICTS was determined using 3-(4,5-dimethyl-2-thiazolyl)-2,5diphenyl-2-H-tetrazolium bromide (MTT) and clonogenic assays. The effect of ICTS on the cell cycle was measured using flow cytometry. Apoptosis was determined by Hoechst 33342 staining, DNA fragmentation assays, and Western blotting for apoptotic proteins. Finally, the effect of ICTS on mitogen-activated protein kinases (MAPKs) was determined by Western blotting. Results: ICTS significantly inhibited proliferation of MCF-7 and MDA-MB-231 human breast cancer cells, HepG2 human liver cancer cells, and A549 human lung cancer cells in vitro. Among the tested cell lines, MCF-7 cells showed the highest sensitivity to ICTS. ICTS significantly inhibited colony formation by MCF-7 cells. Furthermore, exposure of MCF-7 cells to ICTS induced cell cycle arrest at the G1 phase and decreased mitochondrial membrane potential. Hoechst 33342 staining and Western blot analysis for apoptotic proteins suggested that ICTS induced apoptosis in MCF-7 cells. In addition, ICTS activated MAPK signaling in MCF-7 cells by inducing time- and concentration-dependent phosphorylation of JNK, ERK, and p38 MAPK. Conclusion: Our results suggest that ICTS inhibited MCF-7 cell proliferation by inducing apoptosis and activating MAPK signaling pathways.

The Glycyrrhiza uralensis Fisch, one of the famous Chinese medicinal herbs, has been widely used in anti-cancer prescription. We found that glycerrhetinic acid (GA, triterpenoid) and licochalcone A (LCA, flavonoid), two primary constituents of Glycyrrhiza uralensis Fisch, induced cell proliferative inhibition, apoptosis, and autophagy in non-small cell lung cancer (NSCLC) A549 and NCI-H1299 cells. Combined treatment with chloroquine further enhanced GA- or LCA-induced expression of LC3-II and more red-fluorescent puncta than green ones were observed in GA- or LCA-treated cells with transfection of mRFP-EGFP-LC3, suggesting that GA and LCA induces autophagic flux in NSCLC cells. Inhibition of autophagy enhanced GA-induced cell proliferative inhibition and apoptosis in NSCLC cells. In contrast, LCA-induced cell proliferative inhibition and apoptosis were not significantly altered after autophagy inhibition in NSCLC cells. The JNK and IRE1 α were activated after incubation with GA. Pretreatment with the JNK inhibitor SP600125 or silencing of the JNK pathway by siRNA of JNK or c-jun decreased GA-induced autophagy. Moreover, the GA-induced JNK pathway activation and autophagy were decreased by IRE1α knockdown, suggesting that GA induces autophagy through activation of IRE1α-JNK/c-jun pathway. LCA increased the expression of CHOP, and knockdown of CHOP reversed LCA-induced autophagy, suggesting that LCA-induced autophagy is due to induction of CHOP expression. Collectively, both GA and LCA induced cell proliferative inhibition, apoptosis, and autophagy in NSCLC, and inhibition of autophagy might be an effective strategy to enhance the anti-NSCLC effects of Glycyrrhiza uralensis Fisch contained prescriptions.

The JAK2/STAT3 signaling pathway plays a critical role in tumorigenesis, and has been suggested as a potential molecular target for anti-melanoma therapeutics. However, few JAK2 inhibitors were being tested for melanoma therapy. In this study, eight amentoflavone analogues were evaluated for their activity against human malignant melanoma cells. The most potent analogue, compound 1, inhibited the phosphorylation of JAK2 and STAT3 in human melanoma cells, but had no discernible effect on total JAK2 and STAT3 levels. A cellular thermal shift assay was performed to identify that JAK2 is engaged by 1 in cell lysates. Moreover, compound 1 showed higher antiproliferative activity against human melanoma A375 cells compared to a panel of cancer and normal cell lines. Compound 1 also activated caspase-3 and cleaved PARP, which are markers of apoptosis, and suppressed the anti-apoptotic Bcl-2 level. Finally, compound 1 induced apoptosis in 80% of treated melanoma cells. To our knowledge, compound 1 is the first amentoflavone-based JAK2 inhibitor to be investigated for use as an anti-melanoma agent., published_or_final_version