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Cytisine is a quinolizidine alkaloid, which has been reported to be among the major bioactive components of Sophora alopecuraides L. Quinolizidine alkaloids have previously been demonstrated to inhibit the proliferation of several types of tumor cells. However, few studies have investigated the effects of cytisine on cancer cells. The present study was performed to further investigate the molecular mechanisms underlying cytisine‑induced apoptosis of HepG2 human hepatocellular carcinoma cells. The results of an MTT assay demonstrated that cytisine inhibited the growth of HepG2 cells in a dose‑dependent manner. In addition, the induction of apoptosis was detected, as determined by morphological observation and flow cytometry. As determined by fluorescence microscopy, apoptotic morphological alterations were detected following cytisine administration. Flow cytometric analyses demonstrated that cytisine induced cytotoxicity through apoptosis‑like mechanisms in HepG2 cells. Furthermore, western blot analysis was performed to investigate the release of cytochrome c (Cyt‑c) and activation of the caspase cascade, and the results indicated that treatment of HepG2 cells with cytisine induced caspase‑dependent apoptosis via the release of Cyt‑c from the mitochondria, upregulation of caspase‑3 and downregulation of pro‑caspase‑3. These results indicated that cytisine may induce apoptosis of HepG2 cells through the mitochondrial pathway. [ABSTRACT FROM AUTHOR]

S100 calcium binding protein A4 (S100A4) promotes extracellular signal transduction, intercellular adhesion, motility and mobility. Different extracts from Coix lachryma-jobi have been used for the treatment of various types of cancer in Asia. In our previous study, the polysaccharide fraction extact, CP1, induced cell apoptosis of non-small cell lung cancer cells. In the current study, CP1 inhibited migration and invasion of A549 cells in a scratch wound healing assay and matrigel invasion assay, respectively. Furthermore, reverse transcription-polymerase chain reaction and western blotting demonstrated that CP1 downregulated the gene and protein expression levels of S100A4. In silico docking analysis demonstrated that polysaccharides may not interfere with dimerization, whereas, the affinity of polysaccharides for an S100A4-NMIIA pocket was margnially greater than at the dimerization sites. Thus, CP1 inhibited A549 cell migration and invasion potentially via downregulation of S100A4, and may also interact with the binding site of S100A4-NMIIA, which indicated that CP1 has potential as an alternative cancer chemotherapeutic by targeting S100A4. [ABSTRACT FROM AUTHOR]

Background: Mantle cell lymphoma (MCL) is considered an aggressive subtype of non-Hodgkin's lymphoma with variable treatment responses. There is an urgent need to identify novel markers with prognostic and therapeutic value for MCL. Long non-coding RNAs (lncRNAs) have emerged as key regulators in cancers, including MCL. Metastasis-associated lung adenocarcinoma transcript 1(MALAT1), a lncRNA located at pathognomonic translocation site of t (11; 14) of MCL. MALAT1 is known to be overexpressed in solid tumors and hematologic malignancies. However, the pathological role and clinical relevance of MALAT1 in MCL are not completely understood.Methods: We quantified MALAT1 in MCL samples (40) and CD19+ B cells by quantitative real time polymerase chain reaction (qRT-PCR) and correlated levels with clinical outcome. We silenced MALAT1 in MCL cell lines and analyzed cells in tumorigenic assays and formation of transcription complexes.Results: We found that the expression of MALAT1 was elevated in human MCL tumors and cell lines as compared to normal controls, and the elevated levels of MALAT1 correlated with higher MCL international prognostic index (MIPI) and reduced overall survival. MCL with knockdown of MALAT1 showed impaired cell proliferation, facilitated apoptosis and produced fewer clonogenic foci. The increased expression of p21 and p27 upon MALAT1 knockdown was regulated by enhancer of zeste homolog 2 (EZH2). Moreover, decreased phosphorylation of EZH2 at T350 attenuated the binding to MALAT1.Conclusions: Our findings illuminate the oncogenic role of MALAT1, which may serve as a novel biomarker and as a therapeutic target in MCL. [ABSTRACT FROM AUTHOR]

Toxicological studies have shown that phthalates, a class of widely used chemicals, can impair male reproductive function, but epidemiological evidence is in consistent This study aimed to investigate the associations of semen phthalate metabolites with sperm apoptosis and DNA damage in a Chinese population. We assessed sperm apoptosis markers with Annexin V/PI analysis and sperm DNA integrity with comet assay before measuring eight phthalate metabolites in semen by high-performance liquid chromatography and tandem mass spectrometry (HPLC-MS/MS ) among 463 men from Wuhan, China. We found a suggestive do se-response relationship between semen mono-(2-ethylhexyl) phthalate (MEHP) and an increased percentage of Annexin V7PF sperm (p for trend of <0.10). We also observed that semen monomethyl phthalate (MMP) and monoethyl phthalate (MEP) were associated with significant dose-related increases in tail length of the comet (both p for trend of < 0.01). In conclusion, our data indicate that semen MEHP is associated with increased sperm apoptosis and that semen MMP and MEP are associated with increased sperm DNA damage in a Chinese population. [ABSTRACT FROM AUTHOR]

Cichorium endivia. L, consumed either cooked or eaten raw in salads, is a popular kind of vegetable cultivated all around the World. Its components have been widely used in folk medicine in anti-inflammatory therapy. However, the anti-cancer activity of the components has never been reported. In this study, (3S)-1,2,3,4-tetrahydro- β-carboline-3-carboxylic acid (1), an amino acid isolated from C. endivia. L, was found for the first time to show cytotoxic activity in colorectal cancer cell line HCT-8. Compound 1 at concentrations of 0.5-4 μM induced apoptosis of HCT-8 cells in a dose-dependent manner. The compound 1-induced apoptosis in HCT-8 cells was accompanied by the loss of mitochondrial membrane potential, the activation of caspase-3, caspase-8 and caspase-9, the up-regulation of Bax and the down-regulation of Bcl-2. In addition, compound 1 suppressed the activation of NF-κB, which acts as an inhibitor of apoptosis. Taken together, these results suggested that compound 1 could significantly induce apoptosis of HCT-8 cells through the suppression of NF-κB signaling pathway, and thus can be considered as a potential candidate for developing chemotherapeutic drugs against cancer. [ABSTRACT FROM AUTHOR]

Both amphioxus and the sea urchin encode a complex innate immune gene repertoire in their genomes, but the composition and mechanisms of their innate immune systems, as well as the fundamental differences between two systems, remain largely unexplored. In this study, we dissect the mucosal immune complexity of amphioxus into different evolutionary-functional modes and regulatory patterns by integrating information from phylogenetic inferences, genome-wide digital expression profiles, time course expression dynamics, and functional analyses. With these rich data, we reconstruct several major immune subsystems in amphioxus and analyze their regulation during mucosal infection. These include the TNF/IL-1R network, TLR and NLR networks, complement system, apoptosis network, oxidative pathways, and other effector genes (e.g., peptidoglycan recognition proteins, Gram-negative binding proteins, and chitin-binding proteins). We show that beneath the superficial similarity to that of the sea urchin, the amphioxus innate system, despite preserving critical invertebrate components, is more similar to that of the vertebrates in terms of composition, expression regulation, and functional strategies. For example, major effectors in amphioxus gut mucous tissue are the well-developed complement and oxidative-burst systems, and the signaling network in amphioxus seems to emphasize signal transduction/modulation more than initiation. In conclusion, we suggest that the innate immune systems of amphioxus and the sea urchin are strategically different, possibly representing two successful cases among many expanded immune systems that arose at the age of the Cambrian explosion. We further suggest that the vertebrate innate immune system should be derived from one of these expanded systems, most likely from the same one that was shared by amphioxus. [ABSTRACT FROM AUTHOR]

Background: Genetic prion diseases are linked to point and inserted mutations in the prion protein (PrP) gene that are presumed to favor conversion of the cellular isoform of PrP (PrPC) to the pathogenic one (PrPSc). The pathogenic mechanisms and the subcellular sites of the conversion are not completely understood. Here we introduce several PRNP gene mutations (such as, PrP-KDEL, PrP-3AV, PrP-A117V, PrP-G114V, PrP-P102L and PrP-E200K) into the cultured cells in order to explore the pathogenic mechanism of familial prion disease. Methodology/Principal Findings: To address the roles of aberrant retention of PrP in endoplasmic reticulum (ER), the recombinant plasmids expressing full-length human PrP tailed with an ER signal peptide at the COOH-terminal (PrP-KDEL) and PrP with three amino acids exchange in transmembrane region (PrP-3AV) were constructed. In the preparations of transient transfections, 18-kD COOH-terminal proteolytic resistant fragments (Ctm-PrP) were detected in the cells expressing PrP-KDEL and PrP-3AV. Analyses of the cell viabilities in the presences of tunicamycin and brefeldin A revealed that expressions of PrP-KDEL and PrP-3AV sensitized the transfected cells to ER stress stimuli. Western blots and RT-PCR identified the clear alternations of ER stress associated events in the cells expressing PrP-KDEL and PrP-3AV that induced ER mediated apoptosis by CHOP and capase-12 apoptosis pathway. Moreover, several familial CJD related PrP mutants were transiently introduced into the cultured cells. Only the mutants within the transmembrane region (G114V and A117V) induced the formation of Ctm-PrP and caused the ER stress, while the mutants outside the transmembrane region (P102L and E200K) failed. Conclusions/Significance: The data indicate that the retention of PrP in ER through formation of Ctm-PrP results in ER stress and cell apoptosis. The cytopathic activities caused by different familial CJD associated PrP mutants may vary, among them the mutants within the transmembrane region undergo an ER-stress mediated cell apoptosis. [ABSTRACT FROM AUTHOR]

Harnessing the regenerative potential of the central nervous system to repopulate depleted cellular populations from endogenous stem cells would be a novel approach for the treatment of neurological diseases resulting from cell death. Consequently, understanding if and how the central nervous system is capable of such regeneration would determine if such an approach is feasible. In this report, we provide evidence of widespread regenerative response in the spinal cord of amyotrophic lateral sclerosis transgenic mice. However, this regenerative response appears to be largely unproductive. We demonstrate that there is significantly increased gliogenesis, but an absence of convincing neurogenesis. The fact that the neurodegenerative process stimulates a regenerative response suggests that the adult spinal cord has at least limited ability for regeneration. Further studies will determine if this endogenous regenerative process can be enhanced and directed so as to slow or even reverse the natural progression of this devastating disease. [ABSTRACT FROM AUTHOR]

To further understand how the mitogen-activated protein kinase (MAPK) signaling pathways regulate AP-1 activity, we have elucidated the physiological role of these cascades in the regulation of c-jun gene expression. c-Jun is a crucial component of AP-1 complexes and has been shown in vitro to be a point of integration of numerous signals that can differentially affect its expression as well as its transcriptional activity. Our strategy was based on the use of (i) genetically modified fibroblasts deficient in components of the MAPK cascades and (ii) pharmacological reagents. The results demonstrate that c-Jun NH2-terminal protein kinase (JNK) is essential for a basal level of c-Jun expression and for c-Jun phosphorylation in response to stress. In addition to JNK, p38 MAPK or ERK1/2 and ERK5 are required for mediating UV radiation- or epidermal growth factor (EGF)-induced c-Jun expression, respectively. Further studies indicate that p38 MAPK inhibits the activation of JNK in response to EGF, causing a down-regulation of c-Jun. Overall, these data provide important insights into the mechanisms that ultimately determine the function of c-Jun as a regulator of cell fate. [ABSTRACT FROM AUTHOR]

To elucidate the physiological significance of MEK5 in vivo, we have examined the effect of mek5 gene elimination in mice. Heterozygous mice appear to be healthy and were fertile. However, mek5-/- embryos die at approximately embryonic day 10.5 (E10.5). The phenotype of the mek5-/- embryos includes abnormal cardiac development as well as a marked decrease in proliferation and an increase in apoptosis in the heart, head, and dorsal regions of the mutant embryos. The absence of MEK5 does not affect cell cycle progression but sensitizes mouse embryonic fibroblasts (MEFs) to the ability of sorbitol to enhance caspase 3 activity. Further studies with reeks-/- MEFs indicate that MEK5 is required for mediating extracellular signal-regulated kinase 5 (ERK5) activation and for the regulation of the transcriptional activity of myocyte enhancer factor 2. Overall, this is the first study to rigorously establish the role of MEK5 in vivo as an activator of ERK5 and as an essential regulator of cell survival that is required for normal embryonic development. [ABSTRACT FROM AUTHOR]

Caspase-1 plays a key role in inflammatory pathways by processing pro-IL-Iβ into the active cytokine mature IL-1β. Given its sequence similarity with the Caenorhabditis elegans cell death gene ced-3, it has long been speculated that caspase-1 may also play a role in cell death. However, an unequivocal role for caspase-1 in cell death has been questioned, and not definitively demonstrated. Furthermore, if caspase-1 does play a role in cell death, its position in the apoptotic hierarchy has not been clearly defined. Previous studies have shown that caspase-1 knockout (KO) mice and transgenic mice expressing a dominant-negative caspase-1 construct are resistant to ischemic brain injury. We provide direct evidence that caspase-1 plays a key role in neuronal cell death and that caspase-1 is an apical activator of the cell death pathway in the premitochondrial collapse stage. Furthermore, we demonstrate that Rip2/ Cardiak/Rick is a stress-inducible upstream modulator of procaspase-1 apoptotic activation. We provide evidence that Bid cleavage appears to be an important downstream effector of caspase-l-mediated cell death. Our data demonstrate that caspase-1 is an apical mediator of neuronal cell death during in vitro hypoxia, and confirmed in vivo in ischemia, and provide insights into the sequence of events involved in this pathological cell death process. [ABSTRACT FROM AUTHOR]

Epithelial barrier disruption is a major cause of inflammatory bowel disease (IBD),however, the cellular and molecular regulation of intestinal epithelial homeostasis remains largely undefined. Here, we show that the C-type lectin receptor LSECtin (Clec4g) on macrophages is required for protection against dextran sulfate sodiuminduced colitis. Mechanistically, LSECtin promotes apoptotic cell clearance by macrophages and induces the production of antiinflammatory/ tissue repair factors in an engulfment-dependent manner, which in turn stimulates epithelial cell proliferation. Deletion of LSECtin results in defective engulfment by colon macrophages, leading to aberrant proresolving factor production and impaired intestinal epithelium repair. Collectively, our findings suggest that LSECtindependent corpse clearance by macrophages can direct intestinal regeneration and maintenance of the mucosal barrier after injury. [ABSTRACT FROM AUTHOR]

Ulinastatin exhibits anti-inflammatory activity and protects the heart from ischemia/reperfusion injury. However, whether ulinastatin has a protective effect in diabetic cardiomyopathy is yet to be elucidated. The aim of the present study was to investigate the protective effects of ulinastatin against diabetic cardiomyopathy and its underlying mechanisms. A C57/BL6J mice model of diabetic cardiomyopathy was used and mice were randomly assigned to three groups: Control group, diabetes mellitus (DM) group and DM + ulinastatin treatment group. Cardiac function was assessed using echocardiography and the level of inflammatory cytokine high mobility group box 1 (HMGB1) expression was measured using histopathological examination and reverse transcription-quantitative polymerase chain reaction. The levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6 were measured using western blotting and ELISA. The apoptosis rate in the myocardium was assessed by TUNEL assay. Caspase-3 activation, expression of B-cell lymphoma 2 (Bcl-2) and Bcl-2 associated x (Bax) were measured using western blotting, as was the activity of the mitogen activated protein kinase (MAPK) signaling pathway. The results indicated that ulinastatin significantly improved cardiac function in mice with DM. Ulinastatin treatment significantly downregulated HMGB1, TNF-α and IL-6 expression (P<0.05) and significantly reduced the percentage of apoptotic cardiomyocytes (P<0.05) via reduction of caspase-3 activation and the ratio of Bax/Bcl-2 in diabetic hearts (P<0.05). In addition, ulinastatin attenuated the activation of the MAPK signaling pathway. In conclusion, ulinastatin had a protective effect against DM-induced cardiac dysfunction in a mouse model. This protective effect may be associated with the anti-inflammatory and anti-apoptotic abilities of ulinastatin via the MAPK signaling pathway. [ABSTRACT FROM AUTHOR]

Lidocaine, as an anesthetic substance, is often used for surface and spinal anesthesia. However, studies have shown that lidocaine may induce transient neurological symptoms and cauda equina syndrome. In the present study the effects of the ginsenoside Rg1 (Rg1) on lidocaine-induced apoptosis were assessed in Jurkat cells using flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). The data showed that incubation with Rg1 provides protection against lidocaine-induced apoptosis in cultured Jurkat cells. In order to investigate the effect of Rg1 on the apoptosis pathway, caspase 3 gene expression was determined. The results suggested that the protective effect of Rg1 on lidocaine-induced apoptosis is mediated by altering the level of B-cell lymphoma-2 (BCL-2) family proteins and downregulating caspase-3 expression. In conclusion, the present study demonstrated that incubation with Rg1 provides protection against lidocaine-induced apoptosis in cultured Jurkat cells. In addition, the study demonstrated that Rg1 is a notable antiapoptotic molecule that is capable of blocking the caspase-dependent signaling cascade in Jurkat cells, and that the protective effect of Rg1 on lidocaine-induced apoptosis is mediated by altering levels of BCL-2 family proteins and downregulating caspase-3 expression. The present study provides the basis for understanding and evaluating the effect of Rg1 in the in vivo treatment of lidocaine-induced transient neurological symptoms and cauda equina syndrome by lidocaine. [ABSTRACT FROM AUTHOR]

Proteasome inhibitors have demonstrated that targeting protein degradation is effective therapy in multiple myeloma (MM). Here we show that deubiquitylating enzymes (DUBs) USP14 and UCHL5 are more highly expressed in MM cells than in normal plasma cells. USP14 and UCHL5 short interfering RNA knockdown decreases MM cell viability. A novel 19S regulatory particle inhibitor b-AP15 selectively blocks deubiquitylating activity of USP14 and UCHL5 without inhibiting proteasome activity. b-AP15 decreases viability in MM cell lines and patient MM cells, inhibits proliferation of MM cells even in the presence of bone marrow stroma cells, and overcomes bortezomib resistance. Anti-MM activity of b-AP15 is associated with growth arrest via downregulation of CDC25C, CDC2, and cyclin B1 as well as induction of caspase-dependent apoptosis and activation of unfolded protein response. In vivo studies using distinct human MM xenograft models show that b-AP15 is well tolerated, inhibits tumor growth, and prolongs survival. Combining b-AP15 with suberoylanilide hydroxamic acid, lenalidomide, or dexamethasone induces synergistic anti-MM activity. Our preclinical data showing efficacy of b-AP15 in MM disease models validates targeting DUBs in the ubiquitin proteasomal cascade to overcome proteasome inhibitor resistance and provides the framework for clinical evaluation of USP14/UCHL5 inhibitors to improve patient outcome in MM. [ABSTRACT FROM AUTHOR]

AbstractObjective:The objective of the present study was to explore the role of the inhibitor of apoptosis protein (IAP) Livin in radioresistance in nonsmall cell lung cancer (NSCLC).Methods:Lung adenocarcinoma cell lines A549 and SPC-A1 were used for this study. Using the technique of molecular cloning and gene transfection, two Livin isoforms, Livinα and β, respectively, were expressed in A549 cells with the purpose of exploring the role of Livin in radiation resistance of A549 cells. Moreover, a Livin-specific gene-silencing system was developed using SPC-A1 cell line with the purpose of increasing radiosensitivity of SPC-A1 cells.Results:A549 cells were induced by radiation to express Livin isoforms, Livinα and β. A549 cells expressed Livin isoforms stably after gene transfection and the transfected cells demonstrated characteristics of antiradiation. However, Livin gene-silenced SPC-A1 cells exhibited remarkably enhanced radiation sensitivity.Conclusion:The IAP Livin is an important molecule in antiradiotherapy of NSCLC. Livin-specific gene silencing is likely to be an effective means to enhance radiation sensitivity of lung cancer. [ABSTRACT FROM AUTHOR]

J. Neurochem. (2010) 114, 1619–1629. Rho kinase (ROCK) may play an important role in regulating biological events of cells, including proliferation, differentiation and survival/death. Blockade of ROCK promotes axonal regeneration and neuron survival in vivo and in vitro, thereby exhibiting potential clinical applications in spinal cord damage and stroke. Our previous studies have demonstrated that Fasudil, a selective ROCK inhibitor, induced neuroprotection in vitro. Here we used an in vivo model of hypoxia/reoxygenation (H/R) injury to examine the neuroprotective effect of Fasudil, and explore its possible mechanism(s) in vivo. H/R resulted in the loss of hippocampal neurons, accompanied by increased apoptosis of neurons in hippocampus. The expression of ROCK II and activity of ROCK in the brain were increased after H/R, and located only in microglia, but not in astrocytes and neurons. The administration of Fasudil inhibited the activity of ROCK in brain tissue and cultured microglia, and protected hippocampal neurons against H/R injury. Further immunohistochemical analysis and cytokine determination revealed that Fasudil inhibited inducible nitric oxide synthase immunoreactivity in microglia and pro-inflammatory factors in brain tissue after H/R, which is consistent with the observation wherein Fasudil reduced the pro-inflammatory factors nitric oxide, IL-1β, IL-6 and TNF-α, and increased anti-inflammatory factor IL-10 in cultured microglia under normoxic or hypoxic conditions. Our results indicate that inhibition of ROCK by Fasudil may represent a useful therapeutic perspective by inhibiting microglial inflammatory responses in the CNS. [ABSTRACT FROM AUTHOR]

Cancer is the second leading cause of mortality worldwide. Conventional therapies, including surgery, radiation, and chemotherapy, have limited success because of secondary resistance. Therefore, safe, non-resistant, less toxic, and convenient drugs are urgently required. Natural products (NPs), primarily sourced from medicinal plants, are ideal for cancer treatment because of their low toxicity and high success. NPs cure cancer by regulating different pathways, such as PI3K/AKT/mTOR, ER stress, JNK, Wnt, STAT3, MAPKs, NF-kB, MEK-ERK, inflammation, oxidative stress, apoptosis, autophagy, mitophagy, and necroptosis. Among the NPs, steroid saponins, including polyphyllins (I, II, D, VI, and VII), have potent pharmacological, analgesic, and anticancer activities for the induction of cytotoxicity. Recent research has demonstrated that polyphyllins (PPs) possess potent effects against different cancers through apoptosis, autophagy, inflammation, and necroptosis. This review summarizes the available studies on PPs against cancer to provide a basis for future research. [ABSTRACT FROM AUTHOR]

Endometrial cancer (EC) is the most common gynecologic malignancy in world. It has been reported that the mutation rate of FBXW7 is frequent in EC, but the specific functions of FBXW7 remain unknown in EC. In the present study, we revealed the role and mechanism of FBXW7 in EC cells. Compared with adjacent nontumor tissues, the FBXW7 expression level was lower in EC tissues. However, the level of STYX was in contrast with the expression of FBXW7 in EC tissues. And STYX interacted with FBXW7 and then down-regulated its expression level in EC. Over-expression of FBXW7 inhibited cell proliferation and facilitated apoptosis in EC cells, whereas silencing FBXW7 acted an opposite effect on EC cells. And the process of FBXW7 participated the proliferation and apoptosis in EC was regulated by STYX. FBXW7 suppressed the expression of Notch pathway related protein, and further inhibited the phosphorylation of mTOR. In addition, we also found that mTOR activitor (MHY1485) and Notch activator (Jagged-1) reversed the effect of over-expressing FBXW7 on cell proliferation and cell apoptosis. And Notch inhibitor (DAPT) counteracted the impact of over-expressing STYX on cell proliferation and cell apoptosis. Collectively, the present study verified that STYX inhibited the expression level of FBXW7 in EC, and then promoted cell proliferation but suppressed apoptosis through Notch-mTOR signaling pathway, which promoted carcinogenesis and progression of EC. [ABSTRACT FROM AUTHOR]

Maspin has been identified as a tumor suppressor gene in breast cancer, but the underlying regulatory mechanisms remain unclear. In the present study, maspin pcDNA was transfected into MCF-7 cells. microRNA (miR) microarray and reverse transcription-quantitative polymerase chain reaction was used for analysis; the results demonstrated that maspin may inhibit miR-10b, miR-21 and miR-451 expression in MCF-7 cells. In addition, maspin increased the expression of certain miR-21 target genes (phosphatase and tensin homolog, programmed cell death 4 and B-cell lymphoma-2), miR-10b target gene (Homeobox D10; HOXD10) and miR-451 target gene (multidrug resistance protein 1). Furthermore, the results of the present study revealed that decreased expression of miR-21 suppressed the invasion and proliferation of MCF-7 cells. Therefore, in the present study, it was hypothesized that as a tumor-suppressor gene, the potential molecular mechanism of maspin include down-regulating the expression of miR-21 and increasing the expression of specific miR-21 target genes. [ABSTRACT FROM AUTHOR]

Increasing evidence has shown that long non-coding RNAs (lncRNAs) have important biological functions and can be used as a prognostic biomarker in human cancers. However, investigation of the prognostic value of lncRNAs in head and neck squamous cell carcinoma (HNSCC) is in infancy. In the present study, we analyzed the lncRNA expression data in a large number of HNSCC patients (n=425) derived from The Cancer Genome Atlas (TCGA) to identify an lncRNA expression signature for improving the prognosis of HNSCC. Three lncRNAs are identified to be significantly associated with survival in the training dataset using Cox regression analysis. Three lncRNAs were integrated to construct an lncRNA expression signature that could stratify patients of training dataset into the high-risk group and low-risk group with significantly different survival time (median survival 1.85 years vs. 5.48 years; P=0.0018, log-rank test). The prognostic value of this three-lncRNA signature was confirmed in the testing and entire datasets, respectively. Further analysis revealed that the prognostic power of three-lncRNA signature was independent of clinical features by multivariate Cox regression and stratified analysis. These three lncRNAs were significantly associated with known genetic and epigenetic events by means of functional enrichment analysis. Therefore, our results indicated that the three-lncRNA expression signature can predict HNSCC patients' survival. [ABSTRACT FROM AUTHOR]

A series of novel, highly potent, selective inhibitors targeting both CDK4/9 and HDAC1 have been designed and synthesized. N1-(4-((7-Cyclopentyl-6-(dimethylcarbamoyl)-7H-pyrrolo[2,3-d] pyrimidin-2-yl)amino)phenyl)-N8-hydroxyoctanediamide (6e) was discovered. The lead compound 6e with excellent CDK4/9 and HDAC1 inhibitory activity of IC50 = 8.8, 12, and 2.2 nM, respectively, can effectively induce apoptosis of cancer cell lines. The kinase profiling of compound 6e showed excellent selectivity and specificity. Compound 6e induces G2/M arrest in high concentration and G0/G1 arrest in low concentration to prevent the proliferation and differentiation of cancer cells. Mice bared-breast cancer treated with 6e showed significant antitumor efficacy. The insight into mechanisms of 6e indicated that it could induce cancer cell death via cell apoptosis based on CDK4/9 and HDAC1 repression and phosphorylation of p53. Our data demonstrated the novel compound 6e could be a promising drug candidate for cancer therapy. [ABSTRACT FROM AUTHOR]

Baicalin, an active flavone isolated from Scutellaria baicalensis Georgi, has been demonstrated to induce various beneficial biochemical effects such as anti-inflammatory, anti-viral, and antitumor effects. However, the antitumor mechanism of baicalin is not well understood. In the present study, baicalin was demonstrated to inhibit the viability and migration of a widely used ovarian cancer cell line, A2780, in a dose-dependent manner. MTT assays revealed that cell viability significantly decreased in ovarian cancer cells treated with baicalin compared with untreated cells, without effect on normal ovarian cells. Flow cytometric analysis indicated that baicalin suppressed cell proliferation by inducing apoptosis. The underlying mechanisms involved were indicated to be downregulation of the anti-apoptotic protein B-cell lymphoma 2 apoptosis regulator and activation of caspase-3 and -9. In addition, wound healing and transwell assays revealed that cell migratory potential and expression of matrix metallopeptidase (MMP)-2 and MMP-9 were significantly inhibited when cells were exposed to baicalin, compared with untreated cells. The present study therefore suggested that baicalin has the potential to be used in novel anti-cancer therapeutic formulations for treatment of ovarian cancer. [ABSTRACT FROM AUTHOR]

Abdominal aortic aneurysm (AAA) is a common disease that is associated with the proliferation and apoptosis of vascular smooth muscle cells (VSMCs). VSMCs are regulated by microRNAs (miRNA). The aim of the present study was to identify miRNA sequences that regulate aortic SMCs during AAA. miRNA‑504 was identified using a miRNA PCR array and by reverse transcription‑quantitative polymerase chain reaction analysis, and its expression levels were observed to be downregulated in the aortic cells derived from patients with AAA when compared with controls. Transfection of SMCs with pMSCV‑miRNA‑504 vector was performed, and cell proliferation and the expression levels of proliferating cell nuclear antigen (PCNA), replication factor C subunit 4 (RFC4), B‑cell lymphoma‑2 (Bcl‑2) and caspase‑3/9 were measured by western blotting. The mechanisms underlying the effects of miRNA‑504 was then analyzed. The results demonstrated that overexpression of miRNA‑504 significantly upregulated the expression levels of PCNA, RFC4 and Bcl‑2, while caspase‑3/9 expression was significantly inhibited when compared with non‑targeting controls. In addition, miRNA‑504 overexpression was observed to promote the proliferation of SMCs. The expression level of the tumor suppressor, p53, which is known to be a direct target of miRNA‑504, was inhibited following transfection of SMCs with pMSCV‑miRNA‑504. In addition, the expression of the downstream targets of p53, p21 and Bcl‑like protein‑4, were significantly reduced following overexpression of miRNA‑504. These results revealed the anti‑apoptotic role of miRNA‑504 in SMCs derived from patients with AAA via direct targeting of p53. [ABSTRACT FROM AUTHOR]

Apoptosis and DNA oxidative damage serve significant roles in the pathogenesis of steroid-induced femoral head necrosis. Vitamin E demonstrates anti-apoptotic and anti-oxidant properties. Therefore, the present study investigated the effects of vitamin E on osteocyte apoptosis and DNA oxidative damage in bone marrow hemopoietic cells at an early stage of steroid-induced femoral head osteonecrosis. Japanese white rabbits were randomly divided into three groups (steroid, vitamin E-treated, and control groups), each comprising 12 rabbits. Those in the steroid group (group S) were initially injected twice with an intravenous dose of 100 μg/kg Escherichia coli endotoxin, with a 24 h interval between the two injections, and then with an intramuscular dose of 20 mg/kg methylprednisolone, three times at intervals of 24 h in order to establish a rabbit model of osteonecrosis. The vitamin E treated group (group E) received the same treatment as group S, and were administered 0.6 g/kg/d vitamin E daily from the beginning of modeling. The control group (group C) was injected with normal saline at the equivalent dosage and times as the aforementioned two groups. Two time points, weeks 4 and 6 following the completion of modeling, were selected. Osteonecrosis was verified by histopathology with hematoxylin-eosin staining. The apoptosis rate of osteonecrosis was analyzed by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. The apoptosis expression levels of caspase-3 and B-cell lymphoma 2 (Bcl-2), and DNA oxidative damage of bone marrow hematopoietic cells were analyzed by immunohistochemistry. At weeks 4 and 6 following the completion of modeling, the vacant bone lacunae rates of group E were 15.87±1.97 and 25.09±2.67%, respectively, lower than the results of 20.02±2.21 and 27.79±1.39% for group S; and the osteocyte apoptosis indexes of group E were 20.99±2.95 and 33.93±1.62%, respectively, lower than the results of 26.46±3.37 and 39.90±3.74% from group S. In addition, the Bcl-2 expression at week 4 in the femoral head tissues of group E was higher compared with group S; and the proportion of Bcl-2-positive cells of group E was 9.81±1.01%, higher compared with group S at 8.26±1.13%. The caspase-3 staining data at week 4 in femoral head tissues demonstrated that in the 12 femoral heads of group S, four were negative (32%) and eight were positive (68%); in group E, five were negative (45%) and seven were positive (55%); and in group C, 11 were negative (95%) and one was positive (5%). In addition, the DNA oxidative damage rate at week 4 in the bone marrow hemopoietic cells of group E was (7.24±1.44%), lower compared with group S (11.80±1.26%), and higher compared with group C (5.75±1.47%). Vitamin E is effective in intervening in apoptosis through decreasing caspase-3 expression and upregulating Bcl-2 expression, and by alleviating DNA oxidative damage in bone marrow hemopoietic cells at the early stage of steroid-induced femoral head necrosis in rabbit models. [ABSTRACT FROM AUTHOR]

Subarachnoid hemorrhage (SAH) is a hemorrhagic stroke with high mortality and morbidity. An animal model for SAH was established by directly injecting a hemolysate into the subarachnoid space of rats or mice. However, the in vitro applications of the hemolysate SAH model have not been reported, and the mechanisms remain unclear. In this study, we established an in vitro SAH model by treating cortical pyramidal neurons with hemolysate. Using this model, we assessed the effects of recombinant human brain-derived neurotrophic factor (rhBDNF) on hemolysate-induced cell death and related mechanisms. Cortical neurons were treated with 10 ng/mL or 100 ng/mL rhBDNF prior to application of hemolysate. Hemolysate treatment markedly increased cell loss, triggered apoptosis, and promoted the expression of caspase-8, caspase-9, and cleaved caspase-3. rhBDNF significantly inhibited hemolysate-induced cell loss, neuronal apoptosis, and expression of caspase-8, caspase-9, and cleaved caspase-3. Our data revealed a previously unrecognized protective activity of rhBDNF against hemolysate-induced cell death, potentially via regulation of caspase-9-, caspase-8-, and cleaved caspase-3-related apoptosis. This study implicates that hemolysate-induced cortical neuron death represents an important in vitro model of SAH. [ABSTRACT FROM AUTHOR]

Background: Considerable evidence has shown that neuroinflammation and oxidative stress play an important role in the pathophysiology of postoperative cognitive dysfunction (POCD) and other progressive neurodegenerative disorders. Increasing evidence suggests that acetaminophen (APAP) has unappreciated antioxidant and anti-inflammatory properties. However, the impact of APAP on the cognitive sequelae of inflammatory and oxidative stress is unknown. The objective of this study is to explore whether APAP could have neuroprotective effects on lipopolysaccharide (LPS)-induced cognitive impairment in mice.Methods: A mouse model of LPS-induced cognitive impairment was established to evaluate the neuroprotective effects of APAP against LPS-induced cognitive impairment. Adult C57BL/6 mice were treated with APAP half an hour prior to intracerebroventricular microinjection of LPS and every day thereafter, until the end of the study period. The Morris water maze was used to assess cognitive function from postinjection days 1 to 3. Animal behavioural tests as well as pathological and biochemical assays were performed to evaluate LPS-induced hippocampal damage and the neuroprotective effect of APAP.Results: Mice treated with LPS exhibited impaired performance in the Morris water maze without changing spontaneous locomotor activity, which was ameliorated by treatment with APAP. APAP suppressed the accumulation of pro-inflammatory cytokines and microglial activation induced by LPS in the hippocampus. In addition, APAP increased SOD activity, reduced MDA levels, modulated glycogen synthase kinase 3β (GSK3β) activity and elevated brain-derived neurotrophic factor (BDNF) expression in the hippocampus. Moreover, APAP significantly decreased the Bax/Bcl-2 ratio and neuron apoptosis in the hippocampus of LPS-treated mice.Conclusions: Our results suggest that APAP may possess a neuroprotective effect against LPS-induced cognitive impairment and inflammatory and oxidative stress via mechanisms involving its antioxidant and anti-inflammatory properties, as well as its ability to inhibit the mitochondrial permeability transition (MPT) pore and the subsequent apoptotic pathway. [ABSTRACT FROM AUTHOR]

Background: Ovarian cancer (OC) was the primary malignant gynecological cancer and SNARE protein is closely related with tumor progression. Here, we identified SNAP23, a member of SNARE complex, as a potential oncogene in OC. Methods: We determined the expression of SNAP23 in OC tissues and explored the clinical significance through bioinformatics analysis. The effects of SNAP23 on OC cell proliferation, migration, invasion, cell cycle and apoptosis were then evaluated in vitro. Results: SNAP23 is hyper-expressed in OC tumor tissues compared to normal tissues, and increased expression of SNAP23 is associated with a poor progression free survival (HR = 1.24, 95% CI = 1.07-1.44, p = 0.0042). SNAP23 knock down increases cell apoptosis and inhibits cell proliferation, migration and invasion of OC cells. GO analysis reveals that most genes correlated highly with SNAP23 were enriched in metabolic process. Conclusions: Our data suggest that SNAP23 may serve as an oncogene promoting tumorigenicity of OC cells by decreasing apoptotic process. [ABSTRACT FROM AUTHOR]

Background: Long noncoding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) plays key role in the progression of some human cancers. However, the role of NEAT1 in human laryngeal squamous cell cancer (LSCC) is still unknown. We therefore investigated the expression and function of NEAT1 in LSCC. Methods: NEAT1 level in LSCC and adjacent non-neoplastic tissues were detected by qRT-PCR. NEAT1 was knockdown in LSCC cells and cell proliferation, apoptosis and cell cycle were examined. The growth of xenografts with NEAT1 knockdown LSCC cells was analyzed. Results: NEAT1 level was significantly higher in LSCC than in corresponding adjacent non-neoplastic tissues, and patients with neck nodal metastasis or advanced clinical stage had higher NEAT1 expression. Moreover, siRNA mediated NEAT1 knockdown significantly inhibited the proliferation and induced apoptosis and cell cycle arrest at G1 phase in LSCC cells. The growth of LSCC xenografts was significantly suppressed by the injection of NEAT1 siRNA lentivirus. Furthermore, NEAT1 regulated CDK6 expression in LSCC cells which was mediated by miR-107. Conclusion: NEAT1 plays an oncogenic role in the tumorigenesis of LSCC and may serve as a potential target for therapeutic intervention. [ABSTRACT FROM AUTHOR]

One major reason for the failure of advanced colorectal cancer (CRC) treatment is the occurrence of chemoresistance to fluoropyrimidine (FU)-based chemotherapy. Various reports showed that ectopic expression and function of microRNAs (miRNAs) played key roles to mediate apoptosis at the post-transcriptional level. To further explore the possible mechanisms, we evaluated the prognostic effect of miR-218 in patients with CRC receiving 5-FU-based treatment and investigated the proapoptotic role of miR-218 in vitro. Primary tumour specimens and adjacent non-tumour sites were used to determine miR-218 expression distribution and explore its potential prognostic value in response to 5-FU-based treatment in patients with CRC. HCT116 and HT29 cells were transfected with precursor miR-218 or negative control, followed by assays to investigate its influence on apoptosis, cell proliferation and pathways involved in molecular mechanisms of chemoresistance to 5-FU. Results showed that high miR-218 expression was associated with positive response to firstline 5-FU treatment in CRC patients. MiR-218 promoted apoptosis, inhibited cell proliferation and caused cell cycle arrest in CRC cells by suppressing BIRC5 expression. Furthermore, miR-218 enhanced 5-FU cytotoxicity in CRC cells by suppressing the 5-FU targeted enzyme, thymidylate synthase (TS). In conclusion, we demonstrated that high miR-218 expression had a positive prognostic value in 5-FU-based treatments for CRC patients and discovered a novel mechanism mediated by miR-218 to promote apoptosis and to function synergistically with 5-FU to promote chemosensitivity by suppressing BIRC5 and TS in CRC. These suggest the unique potential of miR-218 as a novel candidate for developing miR-218-based therapeutic strategies in CRC. [ABSTRACT FROM AUTHOR]

Background: Local tumor control by standard fractionated radiotherapy (RT) remains poor because of tumor resistance to radiation (radioresistance). It has been suggested that cancer stem cells (CSCs) are more radioresistant than non-CSCs. In previous studies, we have shown IL-6 promotes self-renewal of CD133+ CSC-like cells. In this study, we investigated whether IL-6 plays roles not only in promoting self-renewal of CD133+ cells after radiation, but also in conferring radioresistance of CD133+ cells in NSCLC.Materials and Methods: To compare radiation sensitivity of CSCs and non-CSCs, CD133+ CSC-like and CD133- cell populations were isolated from two NSCLC cell lines, A549 and H157, by immunomagnetic separation and their sensitivities to ionizing radiation were investigated using the clonogenic survival assay. To further study the IL-6 effect on the radiosensitivity of CD133+ CSC-like cells, CD133+ cells were isolated from A549IL-6si/sc and H157IL-6si/sc cells whose intracellular IL-6 levels were manipulated via the lentiviral transduction with IL-6siRNA. Post-irradiation DNA damage was analyzed by γ-H2AX staining and Comet assay. Molecular mechanisms by which IL-6 regulates the molecules associated with DNA repair and anti-apoptosis after radiation were analyzed by Western blot and immunofluoresecence (IF) staining analyses.Results: NSCLC CD133+ CSC-like cells were enriched upon radiation. Survival of NSCLC CD133+ cells after radiation was higher than that of CD133- cells. Survival of IL-6 expressing NSC LC CD133+ cells (sc) was higher than that of IL-6 knocked-down cells (IL-6si) after radiation. IL-6 played a role in protecting NSCLC CD133+ cells from radiation-induced DNA damage and apoptosis.Conclusions: IL-6 signaling promotes DNA repair while protecting CD133+ CSC-like cells from apoptotic death after radiation for lung cancer. A combined therapy of radiation and agents that inhibit IL-6 signaling (or its downstream signaling) is suggested to reduce CSC-mediated radioresistance in lung cancer. [ABSTRACT FROM AUTHOR]

Hypoxic conditions regulate several metabolic enzymes and transcription factors that are involved in cancer, ischemia and pulmonary diseases. The Ras homolog (Rho) family, including Rho member A (RhoA), is involved in reorganization of the actin cytoskeleton, cell migration and in the regulation of apoptosis and gene transcription. The aim of the present study was to investigate the expression of hypoxia-inducible factor (HIF)-α and the activity of RhoA in PC12 neuroblastoma cells under hypoxic conditions. The upregulation of HIF-α and RhoA by hypoxia was determined using reverse transcription-quantitative polymerase chain reaction and western blot assays, cell apoptosis was analyzed using flow cytometry, and the activity of caspase 3 was examined using a western blot assay and caspase 3 activity assay kit. The PC12 cells were induced to apoptosis following exposure to hypoxia, and exhibited increased expression of HIF-α and increased mRNA and protein expression levels of RhoA. The overexpression of HIF-α attenuated the hypoxia-induced apoptosis of the PC12 cells. In addition, RhoA knockdown using small interfering RNA abrogated the antagonism of HIF-1α towards hypoxia-induced apoptosis. The results of the present study confirmed the protective role of HIF-1α and RhoA in hypoxia-induced PC12 cell apoptosis, and that the upregulation of HIF-1α by hypoxia is RhoA-dependent. [ABSTRACT FROM AUTHOR]

Ginsenoside Rg3 is one of the main constituents isolated from Panax ginseng, and exhibits cytotoxic effects against cancer cells. The present study aimed to investigate the effects of ginsenoside Rg3 on human multiple myeloma cells, and determine the underlying molecular mechanisms. The cells were exposed to ginsenoside Rg3 at various concentrations (0-80 µM) for 48 h. A subsequent cell proliferation assay demonstrated that treatment with ginsenoside Rg3 resulted in a dose-dependent inhibition of the proliferation of U266 and RPMI8226 cells. Furthermore, exposure to ginsenoside Rg3 led to a marked increase in the rate of apoptosis in the U266 cells, coupled with increased caspase-3 activity. The ginsenoside Rg3-treated cells also exhibited an elevation in the expression of B-cell lymphoma 2-associated X protein (Bax), a pro-apoptotic protein. Notably, knockdown of Bax protected the U266 cells from Rg3-induced apoptosis. Overall, these findings suggested that ginsenoside Rg3 induced apoptosis in multiple myeloma cells, at least partially, through upregulation of the expression of Bax. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the indirubin-enhanced effects of arsenic disulfide (As2S2) on the proliferation and apoptosis of diffuse large B-cell lymphoma (DLBCL) cells in order to identify an optimum combination therapy. The human DLBCL cells, LY1 and LY8, were treated with different concentrations of indirubin for 24, 48 and 72 h. Next, the cells were treated with 10 µM As2S2 or a combination of 10 µM As2S2 and 20 µM indirubin for 48 h. Cell proliferation inhibition was detected using cell counting kit-8 and cell apoptosis was determined using flow cytometry. The expression levels of Bcl-2, Bcl-2-associated X protein (Bax) and caspase-3 were analyzed by quantitative polymerase chain reaction (qPCR) and western blotting. The DLBCL cell viability exhibited no significant changes at 24, 48 or 72 h with increasing indirubin concentration. In addition, the apoptotic rates of the LY1 and LY8 cells demonstrated no noticeable effects at 48 h with increasing indirubin concentration. Following treatment with the combinat ion of indi rubin and As2S2, the inhibitory and apoptotic rates of the cells were notably increased compared with those of the As2S2-treated group. The qPCR results revealed that indirubin alone had no enhancing effect upon the Bax/Bcl-2 mRNA expression ratio and caspase-3 mRNA expression. Western blot analysis revealed that indirubin alone had an enhancing effect upon the Bax/Bcl-2 protein ratio and procaspase-3 protein expression. In addition, the results demonstrated that the 21-KDa Bax protein was proteolytically cleaved into an 18-KDa Bax in the DLBCL cells treated with the combination of indirubin and As2S2. Indirubin alone did not inhibit proliferation or induce the apoptosis of the LY1 and LY8 cells. However, the combination of indirubin and As2S2 yielded enhancing effects. Therefore, the results of the present study demonstrated that with regard to antitumor activities, As2S2 served as the principal drug, whereas indirubin served as the adjuvant drug. The enhancing effect was due, in part, to the induction of the mitochondrial apoptotic pathway, which involves the cleavage of Bax. [ABSTRACT FROM AUTHOR]

Myocardial infarction (MI) is defined as the deprivation of the myocardial tissue of oxygen and nutrients, resulting in the induction of inflammation and apoptosis of the cardiomyocytes. Poly (ADP-ribose) polymerase 1 (PARP1) is a nuclear enzyme closely associated with MI, that can be activated by DNA damage. Inducible nitric oxide synthase (iNOS) is a critical enzyme among the inflammatory cytokines. The present study aimed to investigate the underlying mechanism of the protective effects of PARP1 and iNOS inhibitor against MI, in rats. A total of 40 male Wistar rats were divided into four groups. The rats were anesthetized with sodium pentobarbital (50 mg/kg), and the left anterior descending coronary artery was occluded by ligation, using a 6-0 polypropylene monofilament suture, at the left atrial apex, in order to induce MI. The rats from each group received an abdominal injection of either dimethylsulfoxide (100 μl, for MI group); PARP-1 inhibitor, 3,4-dihydro-5-[4-(1-piperidinyl)butoxy]-1(2H)- isoquinolinone (DPQ; 10 mg/kg); or iNOS inhibitor, N-(1-naphthyl)ethylenediamine dihydrochloride (1400W; 10 mg/kg). The hearts were harvested from the rats after four weeks. Inhibition of PARP and iNOS activity improved heart function, as determined by serial echocardiography. The rate of apoptosis, as determined by a terminal deoxynucleotidyl-transferase-mediated dUTP nick end labeling assay, was reduced by 39.71 and 39.00% in the DPQ and 1400W groups, respectively, and this was accompanied by the downregulated expression of cleaved caspase-3 and PARP1. Effective inhibition of PARP and iNOS, by DPQ and 1400W, was detected by western blotting and immunofluorescence, and was shown to repress O2 - and nitrotyrosine levels, following MI. The present study confirmed that inhibition of PARP1 and iNOS was able to protect against ischemic myocardial damage, by reducing the levels of apoptosis. [ABSTRACT FROM AUTHOR]

Medulloblastoma is the most common malignant pediatric brain tumor, with metastases present at diagnosis conferring a poor prognosis. Mechanisms of dissemination are poorly understood and metastatic lesions are genetically divergent from the matched primary tumor. Effective and less toxic therapies that target both compartments have yet to be identified. Here, we report that the analysis of several large nonoverlapping cohorts of patients with medulloblastoma reveals MET kinase as a marker of sonic hedgehog (SHH)-driven medulloblastoma. Immunohistochemical analysis of phosphorylated, active MET kinase in an independent patient cohort confirmed its correlation with increased tumor relapse and poor survival, suggesting that patients with SHH medulloblastoma may benefit fromMET-targeted therapy. In support of this hypothesis, we found that the approved MET inhibitor foretinib could suppress MET activation, decrease tumor cell proliferation, and induce apoptosis in SHH medulloblastomas in vitro and in vivo. Foretinib penetrated the blood-brain barrier and was effective in both the primary and metastatic tumor compartments. In established mouse xenograft or transgenic models of metastatic SHH medulloblastoma, foretinib administration reduced the growth of the primary tumor, decreased the incidence of metastases, and increased host survival. Taken together, our results provide a strong rationale to clinically evaluate foretinib as an effective therapy for patients with SHH-driven medulloblastoma. [ABSTRACT FROM AUTHOR]

Natural products are a great source of cancer chemotherapeutic agents. The present study was conducted to investigate whether cucurbitacin B (CuB), one of the most potent and widely used cucurbitacins, inhibits proliferation and induces apoptosis in the A549 lung cancer cell line. Furthermore, CuB induced apoptosis of A549 cells in a concentration- dependent manner, as determined by fluorescence microscopy, flow cytometry and transmission electron microscopy. The present study also demonstrated that CuB dose-dependently inhibited lung cancer cell proliferation, with cell cycle inhibition and cyclin B1 downregulation. Apoptosis induced by CuB was shown to be associated with cytochrome c release, B-cell lymphoma 2 downregulation and signal transducer and activator of transcription 3 pathway inhibition. CuB may prove to be a useful approach for the chemotherapy of lung cancer. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the effect of realgar on the viability, proliferation and apoptosis in the human chronic lymphocytic leukemia (CLL) cell line, MEC-1. Potential mechanisms mediating the effect were also explored in the experiment. Cultured MEC-1 cells were incubated with various concentrations of realgar for 24, 48 and 72 h. A WST-8 assay was employed to evaluate the effect on cell viability. Inhibitory effects on cell proliferation were determined using a 5-bromodeoxyuridine cell proliferation ELISA. The apoptotic effect on MEC-1 cells was evaluated by annexin V-fluorescein isothiocyanate/propidium iodide dual staining, followed by flow cytometry. Quantitative polymerase chain reaction was performed to determine the mRNA expression levels of BCL2-associated X protein (BAX), BCL2-like 1 (Bcl-xL), v-myc myelocytomatosis viral oncogene homolog (avian; c-Myc) and cyclin-dependent kinase inhibitor 1A (p21). It was found that viability and proliferation were significantly reduced while apoptotic rates increased in MEC-1 cells following exposure to realgar. Furthermore, mRNA expression of BAX and c-Myc was upregulated and downregulated, respectively, in realgar-treated MEC-1 cells. In conclusion, the results showed that realgar inhibits viability and proliferation and induces apoptosis of MEC-1 cells in a dose- and time-dependent manner. The effect may depend on the mitochondrial apoptosis pathway. The results of the present study may be beneficial in the identification of a new target therapy for CLL. [ABSTRACT FROM AUTHOR]

Dichloroacetate (DCA), a small molecule mitochondria-targeting agent, can penetrate the blood--brain barrier, showing potential therapeutic effects on brain tumors. Considering the effects of DCA on tumor cellular metabolism, penetrating across the blood--brain barrier, as well as having potential antitumor activity on brain tumors, the purpose of this study is to investigate the antitumor activity of DCA on C6 glioma cells in vitro and in vivo. DCA inhibited C6 glioma cell proliferation, induced C6 cell apoptosis, and arrested C6 cells in S phase. DCA can inhibit the expression of heat shock proteins 70 (Hsp70) in a dose-dependent and time-dependent manner (P < 0.01). Our in vivo antitumor effect results indicated that DCA markedly inhibited the growth of C6 glioma tumors in both C6 brain tumor-bearing rats and C6 tumor-bearing nude mice (P < 0.01). DCA significantly induced the ROS production and decreased the mitochondrial membrane potential in tumor tissues. Our in vivo antitumor effect results also indicated that DCA has potential antiangiogenic effects. In conclusion, DCA may be a viable therapeutic agent in the treatment of gliomas. [ABSTRACT FROM AUTHOR]

Background: Metadherin (MTDH) has been demonstrated as a potentially crucial mediator of various types of human malignancies. However, the expression and role of MTDH in diffuse large-B-cell lymphoma (DLBCL) have not been reported yet. This study aimed to illuminate the role of MTDH in the pathogenesis of DLBCL. Methodology/Principal Findings: A remarkable elevation of MTDH on mRNA level was detected in DLBCL tissues by quantitative polymerase chain reaction (PCR). Using Western-blot analysis we found that the expression of MTDH protein was significantly upregulated in DLBCL cell lines and DLBCL tissues compared with peripheral blood mononuclear cells (PBMCs) from healthy samples and tissues from patients of reactive hyperplasia of lymph node. The results showed high expression of MTDH in 23 of 30 (76.67%) DLBCL tissues by using immunohistochemical analysis and the over expression of MTDH was strongly correlated to the clinical staging of patients with DLBCL (P<0.05). Furthermore, the finding suggested that the increase of MTDH in DLBCL cells could distinctly enhance cell proliferation and inhibit cell apoptosis; meanwhile, inhibition of MTDH expression by specific siRNA clearly enhanced LY8 cell apoptosis. Upregulation of MTDH elevated the protein level of total β-catenin and translocation of β-catenin to the nucleus directly or indirectly. Knockdown of MTDH decreased the level of total, cytoplasmic β-catenin and reduced nuclear accumulation of β-catenin protein. This indicated that the function of MTDH on the development of DLBCL was mediated through regulation of Wnt/β-catenin signaling pathway. Conclusions/Significance: Our results suggest that MTDH contributes to the pathogenesis of DLBCL mediated by activation of Wnt/β-catenin pathway. This novel study may contribute to further investigation on the useful biomarkers and potential therapeutic target in the DLBCL patients. [ABSTRACT FROM AUTHOR]

In order to explore whether the apoptosis in ischemia-reperfusion injury could be affected by Ginkgo biloba extract (GBE) and the free radical scavenger GBE could suppress this affection. Rabbits were randomly divided into sham group, ischemia group, ischemia-reperfusion group (1, 6, 24, 48 h), the drug group (1, 6, 24, 48 h). Measure the rate of apoptosis by flow cytometry, the caspase 9 and apoptosis-inducing factor (AIF) in the cytoplasm and serum by ELISA. Compared with the sham group and ischemia group, the reperfusion group increased the rate of apoptosis, the caspase 9 and AIF in serum have a peak at 24 h after reperfusion, in the cytoplasm the peak at 6 h.GBE inhibit performance has the systemic and local aspects. The apoptosis of nerve cells after spinal cord ischemia-reperfusion has the relationship with the mitochondrial caspase-dependent and caspase-independent pathways and both the local and systemic role. GBE inhibits nerve cell apoptosis by these ways. [ABSTRACT FROM AUTHOR]

Objectives: The protective effect of estrogen on the neurons in Parkinson's disease (PD) is unclear. The present study aimed to investigate the effect of estrogen on the apoptosis and dopaminergic function on a cultured cell model of PD. Methods: The PD model was established by addition of 1-methyl-4-phenylpyridinium (MPP+) to PC12 cell culture. Estrogen was added to cell groups with MPP+ (Estrogen+MPP+), and without MPP+ (Estrogen only group). Cell viability, content of tyrosine hydroxylase (TH), apoptosis ratio, expression of apoptosis-suppression protein Bcl-x and apoptosis-acceleration protein IL-1 beta converting enzyme (ICE) were measured. Results: Cell viability in the Estrogen+MPP+ group was similar to the control group but was higher than in the MPP+ group (P<0.05). The apoptosis ratios in the Estrogen+MPP+ group (33.6%), and the control group (31.3%), were also similar, but it was lower than in the MPP+ group (63.5%, P<0.05). Concentrations of Bcl-x were higher in the Estrogen+MPP+ group, whereas ICE concentrations were lower than in the MPP+ group (P<0.05). Conclusions: Estrogen suppresses apoptosis and improves cell viability in MPP+ induced injuries in the PC12 cells. The beneficial effects of estrogen on the PD model are due to the suppression of pro-apoptotic protein ICE, and stimulation of anti-apoptotic protein Bcl-x. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the effect of a seashell protein Haishengsu (HSS), an extract from a shellfish Tegillarca granosa, on cell growth and the expression of apoptosis genes in leukemia K562 cells. Methods: Cultured K562 cells were treated with HSS at various concentrations (10-40mg/L). The cell cycle, cell growth and the expression of apoptosis suppressor gene bcl-2 and apoptosis promoting gene bax were evaluated. Results: HSS, 20mg/L, inhibited cell cycle in the G0/G1 and S phases. HSS, 20mg/L, also inhibited the growth of K562 cells over time. Expression of bcl-2 gene in the HSS 20mg/L (58.8%±4.7%) and HSS 40mg/L group (26.6%±2.1%) were lower than in the control group (91.0±8.7%, P<0.01). Expression of bax gene in the HSS 20mg/L (77.7±3.6%) and 40mg/L group (90.6±3.7%) were higher than in the control group (10.9±6.6%, P<0.01). Conclusion: HSS suppresses leukemia K562 cell growth by inhibiting the G0/G1 and S phases of the cell cycle. It also induces apoptosis in these leukemia cells by reducing the expression of apoptosis suppressor gene bcl-2, and increasing the expression of apoptosis promoting gene bax. Further studies are required to investigate the clinical efficacy of HSS in leukemia. [ABSTRACT FROM AUTHOR]