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The aberrant expression of DNA methyltransferases (DNMTs) has been considered to be associated with pancreatic carcinogenesis and progression. DNMT3a is widely involved in cell proliferation and cell cycle progression in pancreatic ductal adenocarcinoma (PDAC) cells. However, its regulation of chemosensitivity to gemcitabine (GEM) and oxaliplatin (OXA) in p53-deficient PDAC remains unclear. In the present study, the effect and mechanisms of DNMT3a on GEM and OXA chemosensitivity in p53-deficient PDAC cells were investigated using MTT assay, cell cycle analysis, apoptosis analysis and western blotting. The treatment of GEM and OXA induced S phase arrest by DNA damage, and enhanced the activation of the AKT signaling pathway in Panc-1 cells. Downregulation of DNMT3a increased the chemosensitivity to both GEM and OXA in Panc-1 cells. DNMT3a depletion distinctly abolished S phase arrest induced by GEM and OXA. Further research demonstrated that activation inhibition of CHK1 and AKT, as well as an increase in apoptosis, were involved in DNMT3a-mediated chemosensitivity to GEM and OXA. Taken together, these data demonstrated that DNMT3a serves a crucial role in the regulation of chemosensitivity to GEM and OXA, and suggests a promising therapeutic target for p53-deficient PDAC. [ABSTRACT FROM AUTHOR]

T‑Box (TBX)‑2 is a member of the T‑box gene family, which is aberrantly expressed in numerous types of malignant tumors, and has previously been demonstrated to be conducive to tumor progression by acting as a transcription factor. However, specific information regarding the expression and function of TBX2 in prostate cancer cells remains to be elucidated. The present study demonstrated that silencing of TBX2 by TBX2 small interfering RNA inhibited cell proliferation and promoted cell senescence. It was demonstrated that knockdown of TBX2 inhibited cell metastatic abilities by upregulating E‑cadherin and downregulating N‑cadherin, Vimentin and fibronectin. In addition, the expression of TBX2 in prostate cancer tissues and tumor adjacent tissues was detected by immunohistochemistry. The results indicated that the expression rates of TBX2 were significantly increased in the cancerous tissues, compared with the healthy tumor adjacent tissue, and TBX2 increased staining was associated with the clinical stage and pathological grade. The findings of the present study therefore suggest that TBX2 expression is markedly increased in prostate cancer and TBX2 may act as a potential beneficial therapeutic target for the future treatment of prostate cancer. [ABSTRACT FROM AUTHOR]

The mechanisms of hypertrophic cardiomyopathy (HCM) pathogenesis can be investigated by determining the differences between healthy and disease states at the molecular level. In the present study, large-scale transcriptome sequencing was performed to compare mRNA expression in patients with HCM and control groups using an Illumina sequencing platform. Compared with the genome background, 257 differentially expressed genes (DEGs) were identified in which 62 genes were downregulated and 195 genes were upregulated. Reverse transcription-quantitative polymerase chain reaction was performed to validate the expression pattern of certain mRNAs. Gene ontology enrichment and KEGG analysis of mRNAs was conducted to identify the biological modules and pathological pathways associated with the DEGs. To the best of our knowledge, this is the first time study to investigate the differences in mRNA between patients with HCM and normal controls at the transcriptome level. The results of the study will contributed to the understanding of the important molecular mechanisms involved in HCM and aid the selection of key genes to investigate in the future. [ABSTRACT FROM AUTHOR]

Brain plasticity is very sensitive to the environment. Certain neurotrophic factors and neurotransmitter receptors, including brain-derived neurotrophic factor (BDNF), cyclic adenosine monophosphate response element-binding protein (CREB), stromal cell-derived factor-1 (SDF-1) and its specific receptor, C-X-C motif chemokine receptor 4 (CXCR4), are important in neurogenesis in adult animals. In the present study, the effects of environmental enrichment (EE) on neurogenesis in the dentate gyrus (DG) and subventricular zone (SVZ), and the protein expression levels of BDNF, CREB, SDF-1 and CXCR4 were investigated. Adult rats were randomly assigned as controls or underwent EE for 30 days. Subsequently, immunofluorescence staining was used to analyze cell proliferation in the DG and SVZ, and the differentiation and survival of newly-formed cells in the hippocampus. The protein expression levels of BDNF, phosphorylated CREB (pCREB), protein kinase A catalytic subunit α, SDF-1 and CXCR4 in the hippocampus were assayed by western blotting. Cognitive function was assessed in a Morris water maze. EE improved cognitive function, and increased the proliferation, differentiation and survival of newly-formed neurons in the DG of adult rats; however, EE did not activate neurogenesis in the SVZ. Furthermore, EE enhanced the protein expression levels of BDNF, pCREB, SDF-1 and CXCR4 in the hippocampus. These results provide a theoretical basis to explain the beneficial effects of EE on healthy, adult rats. [ABSTRACT FROM AUTHOR]

Protein kinase B (AKT), is a pivotal component of pathways associated with cell survival, metabolism, invasion and metastasis. AKT mediates anti-apoptotic and proliferative signaling in response to essential cytokines. Tumor necrosis factor receptor-associated factor (TRAF)6, an E3 ubiquitin ligase, has been shown to ubiquitylate, as well as activate AKT. The present study used computational methods to determine the relevant amino acid residues at the binding site of TRAF6 and selected small molecules, which may bind to TRAF6. An ex vivo assay was performed to determine their antitumor activities and the possible mechanism of action. Quinine, a natural alkaloid that is well-known for its therapeutic treatment of malaria, exhibited a distinct antiproliferative and pro-apoptotic effect in HeLa and A549 tumor cell lines via the inhibition of the antiapoptotic protein, B-cell lymphoma (BCL)-2, and activation of the pro-apoptotic factor, BCL-2-associated X protein. Quinine inhibited the lipopolysaccharide (LPS)-induced activation of AKT by inhibiting its phosphorylation at Thr-308 and Ser-473, and reversing LPS-induced proliferation. These results suggested that the inhibition of AKT activation via targeting of TRAF6 with quinine may be a viable anticancer therapeutic approach and a successful example of the alternative use of the original therapeutic properties of this well-known natural product. [ABSTRACT FROM AUTHOR]

Toll-like receptor 4 (TLR4) is considered to have a critical role in the occurrence and development of atherosclerosis in atherosclerosis-prone mice; however, it remains uncertain whether treatment with a TLR4 inhibitor may attenuate atherosclerosis. The present study aimed to determine the vascular protective effects of the TLR4 inhibitor CLI-095 on apolipoprotein E-deficient (ApoE-/-) mice. ApoE-/- mice were fed either chow or a high-fat diet, and were treated with or without CLI-095 for 10 weeks. The mean atherosclerotic plaque area in the aortic sections of CLI-095-treated mice was 54.3% smaller than in the vehicle-treated mice (P=0.0051). In vitro, murine peritoneal macrophages were treated with or without CLI-095, and were subsequently stimulated with oxidized low-density lipoprotein. Treatment with CLI-095 markedly reduced the expression levels of lectin-like oxidized low-density lipoprotein receptor-1 and acyl-coenzyme A:cholesterol acyltransferase-1, and significantly upregulated the expression levels of ATP-binding cassette transporter A1, predominantly via suppressing activation of the TLR4/nuclear factor-κB signaling pathway. The results of the present study indicated that the TLR4 inhibitor CLI-095 has the ability to suppress the progression of atherosclerosis in an in vivo model by reducing macrophage foam cell formation. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRs) regulate a number of physiological and pathological processes, including myocardial chronic hypoxia. Previous studies revealed that the expression of miR-146b is increased in vitro and in vivo following the induction of hypoxia. In the present study, the role of miR-146b in hypoxic cardiomyocytes, and the mechanisms underlying its activity, were investigated. The expression of miR-146b was measured in tissue samples from patients with congenital heart disease by reverse transcription-quantitative polymerase chain reaction. The rat H9c2 cardiomyocyte cell line was transfected with an miR-146b inhibitor or the experimental controls, and the cells were maintained under hypoxic conditions for 72 h. The expression of miR-146b increased following the induction of hypoxia. Transfection with the miR-146b inhibitor enhanced the release of lactate dehydrogenase and increased hypoxia-induced apoptosis, as determined by terminal deoxynucleotidyl transferase dUTP nick-end labeling, Hoechst 33258 staining, JC-1 assay (measuring mitochondrial membrane permeability) and annexin V/propidium iodide analysis. A decreased expression of Bcl-2 was observed, whereas the expression levels of cleaved-caspase 3 and Bax were increased. Western blot analysis and a dual luciferase reporter assay confirmed that ribonuclease L is a direct target of miR-146b. Furthermore, inhibition of miR-146b increased the activation of nuclear factor-κB and signal transducer and activator of transcription 3. In conclusion, the inhibition of miR-146b may increase hypoxia-induced cardiomyocyte apoptosis. [ABSTRACT FROM AUTHOR]

Human interferon-γ (hIFN-γ) is a multifunctional protein known to possess immunoregulatory, antiviral and anticancer functions. In the present study, in order to explore the biological roles of hIFN-γ and its mechanisms of action, IFN-γ was cloned and expressed in Pichia pastoris (P. pastoris) under the control of alcohol oxidase promoter 1 (AOX1). The protein was secreted by two different signal peptides, the native secretion signal peptide of hIFN-γ and the Saccharomyces cerevisiae α signal peptide. Following 96 h of methanol induction, Tricine-SDS-PAGE Coomassie staining, western blot analysis and N-terminal protein sequencing revealed that the level of recombinant hIFN-γ (rhIFN-γ) secreted by the native secretion signal was barely detectable, while the α signal peptide secreted ~300 mg/l. rhIFN-γ was purified by Vivaflow 200, SP Sepharose Fast Flow and Vivaspin 2 ml, yielding >96% of a highly purified rhIFN-γ preparation, with a specific activity of 1x107-1.4x107 IU/mg protein as determined by an antiviral assay. The results demonstrated that the experimental procedures developed are capable of producing a large quantity of active rhIFN-γ from P. pastoris. [ABSTRACT FROM AUTHOR]

Brain plasticity is very sensitive to the environment. Certain neurotrophic factors and neurotransmitter receptors, including brain-derived neurotrophic factor (BDNF), cyclic adenosine monophosphate response element‑binding protein (CREB), stromal cell‑derived factor‑1 (SDF‑1) and its specific receptor, C-X-C motif chemokine receptor 4 (CXCR4), are important in neurogenesis in adult animals. In the present study, the effects of environmental enrichment (EE) on neurogenesis in the dentate gyrus (DG) and subventricular zone (SVZ), and the protein expression levels of BDNF, CREB, SDF‑1 and CXCR4 were investigated. Adult rats were randomly assigned as controls or underwent EE for 30 days. Subsequently, immunofluorescence staining was used to analyze cell proliferation in the DG and SVZ, and the differentiation and survival of newly‑formed cells in the hippocampus. The protein expression levels of BDNF, phosphorylated CREB (pCREB), protein kinase A catalytic subunit α, SDF‑1 and CXCR4 in the hippocampus were assayed by western blotting. Cognitive function was assessed in a Morris water maze. EE improved cognitive function, and increased the proliferation, differentiation and survival of newly‑formed neurons in the DG of adult rats; however, EE did not activate neurogenesis in the SVZ. Furthermore, EE enhanced the protein expression levels of BDNF, pCREB, SDF-1 and CXCR4 in the hippocampus. These results provide a theoretical basis to explain the beneficial effects of EE on healthy, adult rats.

Human interferon-γ (hIFN-γ) is a multifunctional protein known to possess immunoregulatory, antiviral and anticancer functions. In the present study, in order to explore the biological roles of hIFN-γ and its mechanisms of action, IFN-γ was cloned and expressed in Pichia pastoris (P. pastoris) under the control of alcohol oxidase promoter 1 (AOX1). The protein was secreted by two different signal peptides, the native secretion signal peptide of hIFN-γ and the Saccharomyces cerevisiae α signal peptide. Following 96 h of methanol induction, Tricine-SDS-PAGE Coomassie staining, western blot analysis and N-terminal protein sequencing revealed that the level of recombinant hIFN-γ (rhIFN-γ) secreted by the native secretion signal was barely detectable, while the α signal peptide secreted ~300 mg/l. rhIFN-γ was purified by Vivaflow 200, SP Sepharose Fast Flow and Vivaspin 2 ml, yielding >96% of a highly purified rhIFN-γ preparation, with a specific activity of 1 x 10(7)-1.4 x 10(7) IU/mg protein as determined by an antiviral assay. The results demonstrated that the experimental procedures developed are capable of producing a large quantity of active rhIFN-γ from P. pastoris.

This study aimed to detect the expression of mitochondrial mRNA in normal and cancerous gastric tissues and discuss their association with clinicopathological characteristics. Semi-quantitative reverse-transcription PCR was used to analyze mitochondrial transcripts in 42 cases of matched cancerous and normal gastric tissues. Expression of these genes was then statistically analyzed to determine the correlation with the clinicopathological characteristics from the patients. Transcripts of cytochrome c oxidase I (CO I) and NADH dehydrogenase 4 (ND4) were highly expressed in gastric cancer tissues compared to normal gastric tissues (P=0.005 and P=0.001, respectively). The expression levels of CO I and ND4 were higher in the diffused type of gastric cancer than in the intestinal type (P=0.024 and P=0.0002, respectively). Elevated expression of CO I and ND4 were associated with gastric tumorigenesis and tumor dedifferentiation ex vivo.