Arctigenin Induces Apoptosis in Melanoma Cells by Reducing the Expression of BCL-2 and VEGF.

BACKGROUND: To investigate the biological effects of arctigenin on B16-F10 melanoma cells in vitro and to explore its mechanism. METHODS: B16-F10 melanoma cells in vitro were treated with the blank control solution and arctigenin solution of different concentrations, respectively. Cell proliferation and apoptosis were analyzed using the CCK-8 assay and cell loss assay, and the effect of arctigenin on melanoma cell proliferation was evaluated. Western blot was used to analyze the expression of BCL-2 protein and vascular endothelial growth factor (VEGF) in the cells of different groups and to explore the mechanism of action of arctigenin. RESULTS: The proliferation rate of B16-F10 melanoma cells treated with arctigenin solutions was significantly lower than that of the blank control group (P < .05), and the proliferation rate decreased with increasing concentration of arctigenin. The apoptosis rate of B16-F10 melanoma cells treated with arctigenin solutions was significantly higher than that of the blank control group (P < .05), and the apoptosis rate increased with increasing concentration of arctigenin. The expression levels of BCL-2 and VEGF in B16-F10 melanoma cells treated with arctigenin solutions were significantly lower than those in the blank control group (P < .05), and the expression levels decreased as the concentration of arctigenin increased. CONCLUSIONS: Arctigenin can inhibit the proliferation and promote the apoptosis of melanoma cells, and the mechanism may be associated with decreasing the expression of BCL-2 and VEGF in melanoma cells.

Prenatal stress modulates HPA axis homeostasis of offspring through dentate TERT independently of glucocorticoids receptor.

In response to stressful events, the hypothalamic-pituitary-adrenal (HPA) axis is activated, and consequently glucocorticoids are released by the adrenal gland into the blood circulation. A large body of research has illustrated that excessive glucocorticoids in the hippocampus exerts negative feedback regulation of the HPA axis through glucocorticoid receptor (GR), which is critical for the homeostasis of the HPA axis. Maternal prenatal stress causes dysfunction of the HPA axis feedback mechanism in their offspring in adulthood. Here we report that telomerase reverse transcriptase (TERT) gene knockout causes hyperactivity of the HPA axis without hippocampal GR deficiency. We found that the level of TERT in the dentate gyrus (DG) of the hippocampus during the developmental stage determines the responses of the HPA axis to stressful events in adulthood through modulating the excitability of the dentate granular cells (DGCs) rather than the expression of GR. Our study also suggests that the prenatal high level of glucocorticoids exposure-induced hypomethylation at Chr13:73764526 in the first exon of mouse Tert gene accounted for TERT deficiency in the DG and HPA axis abnormality in the adult offspring. This study reveals a novel GR-independent mechanism underlying prenatal stress-associated HPA axis impairment, providing a new angle for understanding the mechanisms for maintaining HPA axis homeostasis.

Design of fast-onset antidepressant by dissociating SERT from nNOS in the DRN.

Major depressive disorder (MDD) is one of the most common mental disorders. We designed a fast-onset antidepressant that works by disrupting the interaction between the serotonin transporter (SERT) and neuronal nitric oxide synthase (nNOS) in the dorsal raphe nucleus (DRN). Chronic unpredictable mild stress (CMS) selectively increased the SERT-nNOS complex in the DRN in mice. Augmentation of SERT-nNOS interactions in the DRN caused a depression-like phenotype and accounted for the CMS-induced depressive behaviors. Disrupting the SERT-nNOS interaction produced a fast-onset antidepressant effect by enhancing serotonin signaling in forebrain circuits. We discovered a small-molecule compound, ZZL-7, that elicited an antidepressant effect 2 hours after treatment without undesirable side effects. This compound, or analogous reagents, may serve as a new, rapidly acting treatment for MDD.

Agomelatine: An Astounding Sui-generis Antidepressant?

Major depressive disorder (MDD) is one of the foremost causes of disability and premature death worldwide. Although the available antidepressants are effective and well tolerated, they also have many limitations. Therapeutic advances in developing a new drug's ultimate relation between MDD and chronobiology, which targets the circadian rhythm, led to a renewed focus on psychiatric disorders. In order to provide a critical analysis about antidepressant properties of agomelatine, a detailed PubMed (Medline), Scopus (Embase), Web of Science (Web of Knowledge), Cochrane Library, Google Scholar, and PsycInfo search was performed using the following keywords: melatonin analog, agomelatine, safety, efficacy, adverse effects, pharmacokinetics, pharmacodynamics, circadian rhythm, sleep disorders, neuroplasticity, MDD, bipolar disorder, anhedonia, anxiety, generalized anxiety disorder (GAD), and mood disorders. Agomelatine is a unique melatonin analog with antidepressant properties and a large therapeutic index that improves clinical safety. Published articles revealed that agomelatine is a melatonin receptors (MT1 and MT2) agonist and 5HT2C receptor antagonist. The effects receptors' on melatonin receptors enable the resynchronization of irregular circadian rhythms with beneficial effects on sleep architectures. In this way, agomelatine is accredited for its unique mode of action, which helps to exert antidepressant effects and resynchronize the sleep-wake cycle. To sum up, an agomelatine has not only antidepressant properties but also has anxiolytic effects.

Abnormal expression profile of plasma-derived exosomal microRNAs in patients with treatment-resistant depression.

Whether microRNAs (miRNAs) from plasma exosomes might be dysregulated in patients with depression, especially treatment-resistant depression (TRD), remains unclear, based on study of which novel biomarkers and therapeutic targets could be discovered. To this end, a small sample study was performed by isolation of plasma exosomes from patients with TRD diagnosed by Hamilton scale. In this study, 4 peripheral plasma samples from patients with TRD and 4 healthy controls were collected for extraction of plasma exosomes. Exosomal miRNAs were analyzed by miRNA sequencing, followed by image collection, expression difference analysis, target gene GO enrichment analysis, and KEGG pathway enrichment analysis. Compared with the healthy controls, 2 miRNAs in the plasma exosomes of patients with TRD showed significant differences in expression, among which has-miR-335-5p were significantly upregulated and has-miR-1292-3p were significantly downregulated. Go and KEGG analysis showed that dysregulated miRNAs affect postsynaptic density and axonogenesis as well as the signaling pathway of axon formation and cell growths. The identification of these miRNAs and their target genes may provide novel biomarkers for improving diagnosis accuracy and treatment effectiveness of TRD.

A novel method for automatic pharmacological evaluation of sucrose preference change in depression mice.

Sucrose preference test (SPT) is a most frequently applied method for measuring anhedonia, a core symptom of depression, in rodents. However, the method of SPT still remains problematic mainly due to the primitive, irregular, and inaccurate various types of home-made equipment in laboratories, causing imprecise, inconsistent, and variable results. To overcome this issue, we devised a novel method for automatic detection of anhedonia in mice using an electronic apparatus with its program for automated detecting the behavior of drinking of mice instead of manual weighing the water bottles. In this system, the liquid surface of the bottles was monitored electronically by infrared monitoring elements which were assembled beside the plane of the water surface and the information of times and duration of each drinking was collected to the principal machine. A corresponding computer program was written and installed in a computer connected to the principal machine for outputting and analyzing the data. This new method, based on the automated system, was sensitive, reliable, and adaptable for evaluation of stress- or drug-induced anhedonia, as well as taste preference and effects of addictive drugs. Extensive application of this automated apparatus for SPT would greatly improve and standardize the behavioral assessment method of anhedonia, being instrumental in novel antidepressant screening and depression researching.

Effects of dibutyl phthalate on lipid metabolism in liver and hepatocytes based on PPARα/SREBP-1c/FAS/GPAT/AMPK signal pathway.

Phateacid esters (PAEs), such as dibutyl phthalate (DBP), have been widely used and human exposure results into serious toxic effects; such as the development of fatty liver disease. In the present study, SD rat models for in vivo study (normal and fatty liver model group) and hepatocytes for in vitro study (normal and abnormal lipid metabolism model group) were established to determine the effects of DBP on liver function and discover the possible mechanisms. Meanwhile, the peroxisome proliferator activated receptor (PPARα) blocker, GW6471, with the Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) activator, AICAR, were applied in vitro study to clarify the role of PPARα/SREBP-1c/FAS/GPAT/AMPK signal pathway in the process. Results suggested that DBP could activate PPARα signaling pathway and affected the protein expression of SREBP, FAS and GPAT to cause hyperlipidemia and abnormal liver function. DBP also could inhibit the phosphorylation and activation of AMPK to inhibit the decomposition and metabolism of lipids. Interestingly, the effects of DBP could be alleviated by GW6471 and AICAR. Our experimental results provide reliable evidence that DBP exposure could further induce liver lipid metabolism disorder and other hepatic toxicity through PPARα/SREBP-1c/FAS/GPAT/AMPK signal pathway.

miR-132 can inhibit glioma cells invasion and migration by target MMP16 in vitro.

Gliomas are the most common malignant primary brain tumors, and new clinical biomarkers and therapeutic targets are imminently required. MicroRNAs (miRNAs) are a novel class of small non-coding RNAs (∼22nt) involved in the regulation of various biological processes. Here, by using real-time polymerase chain reaction, miRNA-132 was found to be significantly deregulated in glioma tissues. Based on the prediction of the target genes of miR-132, we hypothesized that there is a significant association between miR-132 and matrix metalloproteinase (MMP) 16 (MT3-MMP), a protein of the MMP family. We showed that the up-expression of miR-132 inhibited cell migration and invasion in the human glioma cell lines A172, SHG44, and U87. Furthermore, the overexpression of miR-132 reduced the expression of MMP16 in A172, SHG44, and U87 cells. Taken together, our study suggested that miR-132 affects glioma cell migration and invasion by MMP16 and implicates miR-132 as a metastasis-inhibiting miRNA in gliomas.

miR-494-3p Regulates Cellular Proliferation, Invasion, Migration, and Apoptosis by PTEN/AKT Signaling in Human Glioblastoma Cells.

Malignant gliomas are the most common primary brain tumors, and the molecular mechanisms involving their progression and recurrence are still largely unclear. Substantial data indicate that the oncogene miR-494-3p is significantly elevated in gliomas, but the molecular functions of miR-494-3p in gliomagenesis are largely unknown. The present study aimed to explore the role of miR-494-3p and its molecular mechanism in human brain gliomas, malignant glioma cell lines, and cancer stem-like cells. The expression level of miR-494-3p in 48 human glioma issues and 8 normal brain tissues was determined using stem-loop real-time polymerase chain reaction (PCR). To study the function of miR-494-3p inhibitor in glioma cells, the miR-494-3p inhibitor lentivirus was used to transfect glioma cells. Transwell invasion system was used to estimate the effects of miR-494-3p inhibitor on the invasiveness of glioma cells. A mouse model was used to test the effect of miR-494-3p inhibitor on glioma proliferation and invasion in vivo. Results showed that the expression of miR-494-3p in human brain glioma tissues was higher than in normal brain tissues. Downregulated expression of miR-494-3p can inhibit the invasion and proliferation and promote apoptosis in glioma cells. Quantitative reverse transcription PCR and Western blotting analysis revealed that the expression of PTEN was increased after downexpression of miR-494-3p in glioma cells (U87 and U251). miR-494-3p inhibitor could prevent migration, invasion, proliferation, and promote apotosis in gliomas through PTEN/AKT pathway. Therefore, the study results have shown that miR-494-3p may act as a therapeutic target in gliomas.

MicroRNA-16 inhibits glioma cell growth and invasion through suppression of BCL2 and the nuclear factor-κB1/MMP9 signaling pathway.

Recent studies have identified a class of small non-coding RNA molecules, named microRNA (miRNA), that is dysregulated in malignant brain glioblastoma. Substantial data have indicated that miRNA-16 (miR-16) plays a significant role in tumors of various origins. This miRNA has been linked to various aspects of carcinogenesis, including cell apoptosis and migration. However, the molecular functions of miR-16 in gliomagenesis are largely unknown. We have shown that the expression of miR-16 in human brain glioma tissues was lower than in non-cancerous brain tissues, and that the expression of miR-16 decreased with increasing degrees of malignancy. Our data suggest that the expression of miR-16 and nuclear factor (NF)-κB1 was negatively correlated with glioma levels. MicroRNA-16 decreased glioma malignancy by downregulating NF-κB1 and MMP9, and led to suppressed invasiveness of human glioma cell lines SHG44, U87, and U373. Our results also indicated that upregulation of miR-16 promoted apoptosis by suppressing BCL2 expression. Finally, the upregulation of miR-16 in a nude mice model of human glioma resulted in significant suppression of glioma growth and invasiveness. Taken together, our experiments have validated the important role of miR-16 as a tumor suppressor gene in glioma growth and invasiveness, and revealed a novel mechanism of miR-16-mediated regulation in glioma growth and invasiveness through inhibition of BCL2 and the NF-κB1/MMP-9 signaling pathway. Therefore, our experiments suggest the possible future use of miR-16 as a therapeutic target in gliomas.

[Phenotype of SHG-44 glioma stem cell spheres and pathological characteristics of their xenograft tumors].

OBJECTIVE: To study the phenotype and tumorigenicity of SHG-44 glioma stem cell spheres and the pathological characteristics of their xenograft tumors. METHODS: SHG-44 glioma cells were cultured under neural stem cell medium and glioma stem cell spheres were collected. Immunocytochemistry was used to dectet the expression of CD133, nestin, A2B5, vimentin, VEGFR-2 and IDH R132H. Cell spheres were induced using serum-containing medium, and the expression of CD133, nestin, vimentin, GFAP, ß-III tubulin and GalC in the cell spheres were detected. The expression of CD133, nestin, VEGFR-2, GFAP, S-100 and CD34 in the intracranial xenograft tumor tissues was detected using immunohistochemistry. The pathological characteristics of orthotopic xenograft tumors generated from the SHG-44 glioma cells and SHG-44 glioma stem cell spheres were compared. RESULTS: SHG-44 glioma stem cell spheres were collected successfully after cultured under neural stem cell medium. The ratio of CD133(+) cells in the passage 10 SHG-44 glioma stem cell spheres was (71.63 ± 5.92)%, significantly higher than that in the SHG-44 glioma cells [(1.95 ± 1.45)%]. Immunocytochemistry showed that in the SHG-44 glioma cell spheres, the ratio of nestin(+) cells was (84.06 ± 7.58)%, vimentin(+) cells (29.11 ± 3.44)%, VEGFR 2(+) cells (64.44 ± 3.69)%, and A2B5(+) cells (14.08 ± 2.19)%. A subpopulation of cells with mutation of IDH R132H was detected harboring in the SHG-44 glioma cell spheres. After induction of differentiation with serum-containing medium, the ratio of CD133(+) cells was (1.89 ± 1.27)%, nestin(+) cells (6.67 ± 2.75)%, vimentin(+) cells (93.75 ± 2.95)%, GFAP (+) cells (91.33 ± 4.75)%, ß-III tubulin(+) cells (82.36 ± 4.02)%, and GalC(+) cells (8.92 ± 3.19)%. Immunohistochemistry showed positive expression of GFAP, S-100, VEGFR-2, and negative of CD133 and nestin in the orthotopic xenograft tumors. A very small amount of human-specific CD34 cells formed a tubular structure. Compared with the SHG-44 glioma cell-formed xenograft tumor, the SHG-44 glioma stem cell-formed xenograft tumor exhibited a higher local invasiveness. CONCLUSIONS: SHG-44 glioma cell spheres are successfully collected after cultured under neural stem cell medium. They belong to the CD133(+)A2B5(-) GSC subpopulation, highly expressing VEGFR-2, possess the ability of both self-renewal and multi-directional differentiation, and may participate in the formation of vasculogenic mimicry.

UHRF2 mRNA expression is low in malignant glioma but silencing inhibits the growth of U251 glioma cells in vitro.

UHRF2 is a member of the ubiquitin plant homeo domain RING finger family, which has been proven to be frequently up-regulated in colorectal cancer cells and play a role as an oncogene in breast cancer cells. However, the role of UHRF2 in glioma cells remains unclear. In this study, we performed real-time quantitative PCR on 32 pathologically confirmed glioma samples (grade I, 4 cases; grade II, 11 cases; grade III, 10 cases; and grade IV, 7 cases; according to the 2007 WHO classification system) and four glioma cell lines (A172, U251, U373, and U87). The expression of UHRF2 mRNA was significantly lower in the grade III and grade IV groups compared with the noncancerous brain tissue group, whereas its expression was high in A172, U251, and U373 glioma cell lines. An in vitro assay was performed to investigate the functions of UHRF2. Using a lentivirus-based RNA interference (RNAi) approach, we down-regulated UHRF2 expression in the U251 glioma cell line. This down- regulation led to the inhibition of cell proliferation, an increase in cell apoptosis, and a change of cell cycle distribution, in which S stage cells decreased and G2/M stage cells increased. Our results suggest that UHRF2 may be closely related to tumorigenesis and the development of gliomas.

Orthotopic model of SHG-44 in the enhanced green fluorescent protein nude mouse.

Naturally fluorescent proteins have been widely used in biological research. In this study, we found that the simple and effective way to obtain enhanced green fluorescent protein (EGFP) nude mice is to cross transgenic EGFP C57BL/6J mice with nude (nu/nu) mice. EGFP expression is identified by tail genotyping. Establishment of the orthotopic EGFP nude mouse model used surgical orthotopic implantation. The morphology and human glioma cell markers, such as glial fibrillary acidic protein (GFAP) and S-100, remain unchanged in this mouse model. The tumor blood vessels obtained from the orthotopic model show brilliant EGFP fluorescence as observed by fluorescence microscopy. These findings suggested that this is an ideal mouse model with which to study interaction among host, tumor, and tumor microenvironment; the findings also suggested that the host (EGFP nude mouse) was involved in tumor angiogenesis.

Analysis of isocitrate dehydrogenase 1 mutation in 97 patients with glioma.

The objective of this study is to investigate the expression and significance of isocitrate dehydrogenase 1 (IDH1) mutation in different subtypes of human gliomas. Direct DNA sequencing, western blot, and immunohistochemistry were used to detect IDH1 mutation and IDH1 gene expression levels in 97 cases of glioma and 9 cases of other CNS tumors. IDH1 mutation was heterozygous, with wild-type arginine 132 replaced by histidine (R132H). Expression in different glioma subtypes was (1) 0 out if 5 in pilocytic astrocytoma; (2) 15 out of 22 in diffuse astrocytoma, 6 out of 9 in oligodendroglioma, 4 out of 6 in oligoastrocytoma, and 0 out of 4 in ependymoma; (3) 11 out of 19 in anaplastic astrocytoma, 4 out of 7 in anaplastic oligodendroglioma, 3 out of 4 in anaplastic oligoastrocytoma, and 0 out of 3 in anaplastic ependymoma; and (4) 1 out of 6 in primary glioblastoma, 8 out of 10 in secondary glioblastoma, and 0 out of 2 in medulloblastoma. IDH1 mutation is a somatic mutation that is found only in some glioma subtypes. It can be used as a molecular marker for glioma subtypes. For example, it can be used to distinguish primary glioblastoma from secondary glioblastoma, combining TP53 mutation and loss of heterozygosity involving 1p/19q. It can also be used as a marker for some gliomas. For example, it can be used to distinguish pilocytic astrocytoma from diffuse astrocytoma, combining detected BRAF proto-oncogene mutations.

A novel gene RNF138 expressed in human gliomas and its function in the glioma cell line U251.

BACKGROUND: The gliomas represent the most common primary malignant brain tumors; however, little is known about the molecular pathogenesis of these tumors. Recent research reveals that the oncogenesis and development of gliomas have a close relation to the overexpression of several oncogenes and the inactivation of tumor suppressor genes. Whether the RING finger protein, RNF138, a newly discovered protein, plays a role in glioma oncogenesis is unknown. The present study investigates the expression levels of RNF138 mRNA in glioma samples and noncancerous brain samples and its function in the human glioma cell line U251. METHODS: RT-PCR was used to ascertain the expression of RNF138 mRNA in the glioma cell lines U251, SHG44, U87, A172, and U373. The RNF138 mRNA expression levels of 35 pathological confirmed glioma samples (Grade I - 4 cases, Grade II - 13 cases, Grade III - 11 cases, and Grade IV - 7 cases) and five noncancerous brain tissue samples were analyzed by real-time quantitative PCR. By RNA interference (RNAi) with the lentivirus vector system, the expression of RNF138 was inhibited in the human astrocytomas-glioblastoma multiforme cell line U251. The effects of RNF138-knockdown on cell proliferation were assessed by Cellomics, and cell cycle and cell apoptosis were assessed by FACS. RESULTS: The RNF138 mRNA is expressed in the five glioma cell lines, and its expression level is significantly higher in glioma tissue than in noncancerous brain tissue. By down-regulation of RNF138 expression, U251 cell proliferation was inhibited and cell apoptosis increased. At the same time, S stage cells lessened and G2 stage cells increased. CONCLUSION: The RNF138 gene is highly expressed in glioma tissue and glioma cell lines. It plays an important role in glioma cell proliferation, apoptosis, and cell cycle.

[Celastrol in the inhibition of neovascularization].

OBJECTIVE: To study the inhibition effect of celastrol on neovascularization. METHODS: The effect of celastrol on the in vitro proliferation of endothelial cell of vessel (ECV) was examined by MTT assay. The effect of celastrol on endothelial cell migration, tube formation on Matrigel and Chick chorioallantoic membrane angiogenesis was also examined. Matrigel plug assay was used to evaluate the effect of celastrol on angiogenesis in vivo. RESULTS: The proliferation of ECV was inhibited significantly by celastrol with IC(50) being 1.33 microg/ml. Celastrol inhibited endothelial cell migration and tube formation in a dose-dependent manner. Celastrol also inhibited angiogenesis both in Matrigel plug of mouse model and in chick chorioallantoic membranes. CONCLUSION: Celastrol, which can inhibit angiogenesis, could be developed as an antiangiogenic drug.

A2B5 lineages of human astrocytic tumors and their recurrence.

Astrocytomas are very common intracranial glial cell neoplasms with an inherent tendency to progress. However, the heterogeneity of the morphological features and clinical behavior of the tumors makes accurate prognosis based on the histopathological grading system very difficult. Studies demonstrated that astrocytes have two distinctive cell lineages, and tumors arisen from these two astrocytic lineages have been speculated to have different biological and clinical manifestations. The present study aimed to delineate these two astrocytic lineages in human astrocytomas by using different immunohistochemical markers and to correlate the cell lineages of the tumors with their recurrence. Three markers were used, namely the A2B5 antigen, which is present in type 2 astrocytes but absent in type 1 astrocytes, glial fibrillary acidic protein (GFAP), a marker for astrocytes, and galactocerebroside (GC), a marker for oligodendrocytes. It was found that astrocytomas sharing the A2B5+ lineage (A2B5 positive and GFAP positive) have a significantly higher recurrence rate than the tumors of the A2B5- lineage (A2B5 negative and GFAP positive). Immunohistochemical staining and PCR-single-stranded conformational polymorphism analysis showed that p53 overexpression and p53 mutations were closely associated with the recurrent astrocytomas, and p53 abnormalities were more frequently detected in astrocytomas of the A2B5+ lineage. Quantification of proliferation by counting argyrophil nucleolar organizer regions (AgNORs) indicated a higher AgNOR count in the A2B5+ lineage than the A2B5- lineage. Our findings thus suggest that astrocytomas share similar antigenicity with astrocytes, and that the A2B5+ lineage exhibited a higher recurrence rate than the A2B5- lineage. The higher recurrence rate of the A2B5+ tumors may be in part related to the higher frequency of p53 abnormalities found in the tumors and the higher proliferative activity as reflected by the higher AgNOR count of the tumors.