The p26, a multifunctional ubiquitin-binding protein, has been proposed to be involved in protein degradation as a component within the ubiquitin-proteasome and autophagy-lysosome systems. As a scaffolding protein with several different kinds of protein-protein interaction domains, p62 mediates various cellular functions. Importantly, p62 plays a critical role in cell's selective autophagy and oxidative stress response, which are associated with the pathogenesis of several human diseases. In this review, we describe the structure of p62 and the mechanism of connection between p62 and ubiquitin-proteasome system/autophagy, so as to provide some perspectives on p62 research.
Adaptor Proteins, Signal Transducing ; physiology ; Autophagy ; Humans ; Oxidative Stress ; Proteasome Endopeptidase Complex ; Protein Interaction Domains and Motifs ; Proteolysis ; Ubiquitin

BACKGROUND: Tumor necrosis factor-associated protein 1 (TRAP1) is a heat-shock protein 90-related mitochondrial chaperone. Accumulative evidence has demonstrated that TRAP1 overexpression is closely related to carcinogenesis. However, the exact function and mechanism of TRAP1 in the occurrence of laryngeal carcinoma remains unclear. OBJECTIVE: To investigate whether RNA interference can inhibit TRAP1 overexpression and to explore its effects on growth and apoptosis of CD133+CD44+ laryngeal carcinoma stem cells. METHODS: CD133+CD44+ laryngeal carcinoma stem cells were sorted from human laryngeal carcinoma Hep-2 cellsusing immunomagnetic beads. The shRNA sequence of TRAP1 was designed and synthesized and CD133+CD44+ laryngeal carcinoma stem cells were transfected with LipofectamineTM 2000. Cell counting kit-8 assay, colony formation assay and flow cytometry were used to investigate the effects of interference of TRAP1 expression on growth and apoptosis of CD133+CD44+ laryngeal carcinoma stem cells. Spectrophotometric method was used to detect the activity of caspase-3, -8 and -9. RESULTS AND CONCLUSION: TRAP1 mRNA and protein expression levels were significantly decreased in TRAP1 shRNA-transfected CD133+CD44+ laryngeal carcinoma stem cells (P < 0.01). Compared with the blank control and negative control groups, the growth and colony formation of CD133+CD44+ laryngeal carcinoma stem cells were significantly inhibited in the TRAP1 shRNA-transfected group (P < 0.05). Apoptosis of CD133+CD44+ laryngeal carcinoma stem cells was significantly inhibited in the TRAP1 shRNA-transfected group as compared with the blank control and negative control groups (P < 0.05). TRAP1 shRNA-mediated cell apoptosis was associated with the activation of caspase-3, -8 and -9. These results suggest that RNA interference targeting inhibition of TRAP1 suppresses cell growth but promotes apoptosis in CD133+CD44+ aryngeal carcinoma stem cells. TRAP1 is likely to be a gene target for treatment of laryngeal carcinoma.

Objective To investigate the effect of lysyl oxidase (LOX) gene expression on proliferation, invasion and radiotherapy sensitivity in laryngeal cancer Hep-2 cells. Methods Hep-2 cells were divided into control group (normal cultured), negative control group (transfection reagent) and transfection group (LOX siRNA transfected). The expressions of LOX, Ki-67, PCNA, MMP-2 and MMP-9 mRNA were detected by real time-PCR and Western blot methods. The cell sur-vival rate and apoptosis irradiated by different doses of X-rays (0, 3, 6, 9, 12, 15 and 18 Gy) were detected by MTT and flow cytometry (FCM). Results The expression levels of LOX, Ki-67, PCNA, MMP-2 and MMP-9 protein and mRNA were sig-nificantly lower in Hep-2 cells after transfection than those of control group and negative control group (P<0.05). The cell survival rate was significantly inhibited 24 hours after irradiation (12, 15 and 18 Gy) in a dose-dependent manner (P<0.05). The apoptotic rate of transfection cells combined with radiotherapy was significantly higher than that of control and the nega-tive control groups (%:79.11 ± 1.26 vs 5.01 ± 1.02, 4.95 ± 1.12, 43.21 ± 2.1,P<0.05). Conclusion The expression of LOX can be down-regulated after LOX siRNA transfection, inhibiting proliferation and enhancing radiosensitivity, which may be related to the down-regulation of Ki-67, PCNA, MMP-2 and MMP-9 protein expression.

Objective To observe changes of erythropoietin (EPO) and rheology in moderate and severe obstructive sleep apnea hypopnea syndrome (OSAHS) patients after the noninvasive positive pressure ventilation (NPPV) treatment. Methods Healthy adults were selected as control group (n=40) while moderate to severe OSAHS patients were selected as OSAHS group. OSAHS group was underwent NPPV treatment then, Levels of sleep apnea hypopnea index (AHI), sleep mean minimum oxygen saturation (LSaO2) and serum erythropoietin (EPO) were assessed, routine blood test and hemodynam-ic indexes were also checked before treatment and 1 and 3 months after treatment in both groups. Results In both groups serum EPO, blood, blood rheology indexes, AHI, LSaO2 were analysised at each time point by ANOVA repeated measures, all of which show significant different between groups and between each time points within the same group. Indexes in OSAHS group improved with prolonged treatment , but they are in the normal range in the control. Conclusion OSAHS pa-tients with NPPV therapy can significantly relieve hypoxia, reduce serum EPO level and blood viscosity. So NPPV has impor-tant clinical significance in prevention and treatment of OSAHS.

OBJECTIVETo study the effect of CEA gene regulation on the anti-tumor activity of oncolytic adenovirus H101 to esophageal carcinoma, and to explore the intrinsic factors influencing H101 sensitivity.

METHODSStable human esophageal cancer cell line EC9706 cells with lower (EC9706-SCEA) and higher CEA expression (EC9706-CEA) were chosen, thawed and cultured, and then to analyse the influence of CEA expressed at different levels on cell growth. The cytotoxic effect of H101 was assayed by in vitro and nude mouse in vivo.

RESULTSThe cell growth experiment showed that the population doubling time of EC9706-SCEA, EC9706-CEA and EC9706 cells were (30.9 ± 2.0) h, (31.1 ± 2.5) h and (29.1 ± 2.6) h, respectively, showing no significant difference among them (P > 0.05). The cytotoxic activity of H101 was higher on EC9706-SCEA than on other four groups, when MOI was ≥ 0.01 PFU (P < 0.05). The mouse experiment showed that H101 inhibited the growth of transplanted tumors in all experimental groups. Its effect on CEA-silenced tumors (inhibition rate was 61.5% to 74.5%) was significantly higher than that on CEA-overexpression tumors (32.3% to 38.5%) and control EC9706 transplanted tumors (35.5% to 44.8%). There was a significant difference between them (P < 0.05).

CONCLUSIONSThe results in vitro and in vivo experiments show that H101 can enhance the cytotoxic effect on EC9706 cells with lower CEA expression. To silence the expression of CEA may provide a novel strategy for target gene therapy of esophageal carcinoma.

Adenoviridae ; physiology ; Animals ; Carcinoembryonic Antigen ; genetics ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; Esophageal Neoplasms ; metabolism ; pathology ; therapy ; Female ; Gene Silencing ; Humans ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Neoplasm Transplantation ; Oncolytic Virotherapy ; Oncolytic Viruses ; physiology ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; genetics ; Tumor Burden

OBJECTIVETo investigate the chemical constituents of Acroptilon repens.

METHODThe ethanol extract of A. repens was isolated and purified by means of chromatography. These compounds were identified by their spectral data.

RESULT11 compounds were isolated and identified as 2alpha, 9beta-dihydroxy-dehydrocostus lactone (1) , cynaropicrin (2) , apigenin (3) , stigmasterol (4) , 4' -hydroxywogonin (5) , ethyl caffeate (6) , p-methoxy-cinnamic acid (7) , luteolin (8) , daucosterol (9) , apigenin-7-O-beta-D-glucoside (10) , syringin (11).

CONCLUSIONCompounds 5-11 were isolated from A. repens for the first time. Compound 1 is new compounds.

Apigenin ; chemistry ; isolation & purification ; Asteraceae ; chemistry ; Caffeic Acids ; chemistry ; isolation & purification ; Flavanones ; chemistry ; isolation & purification ; Lactones ; chemistry ; isolation & purification ; Molecular Structure ; Plant Extracts ; chemistry ; isolation & purification ; Plants, Medicinal ; chemistry ; Sesquiterpenes ; chemistry ; isolation & purification

To investigate the potential ability of the nitrite to induce neuronal differentiation of PC12 cells, cultured PC12 cells planted on matrigel in the presence or absence of sodium nitrite were employed as model, nerve growth factor (NGF) served as a positive control. After 48 h, sodium nitrite enhanced cell viability and vascular endothelial growth factor (VEGF) secretion. Same as the effect of NGF, sodium nitrite (1.4 mmol x L(-1)) treated cultures contained a greater proportion of cells bearing neurites and neurites were much longer than those found in negative control cultures (P < 0.05). Compared with the negative control, sodium nitrite (1.4 mmol x L(-1)) also upregulated the expression of VEGF mRNA (P < 0.05) and hypoxia inducible factor 1 alpha (HIF-1 alpha) or VEGF protein expression (P < 0.05) in cultures of PC12 cells. On the other hand, these effects of the sodium nitrite were likely mediated by HIF-1alpha, since their effects were antagonized by addition of HIF-1alpha inhibitor YC-1. Taken together, these results suggest that low doses of sodium nitrite could induce neurite outgrowth in PC12 cells by activating the HIF-1alpha-VEGF pathway.
Animals ; Cell Differentiation ; drug effects ; Cell Survival ; drug effects ; Food Preservatives ; pharmacology ; Hypoxia-Inducible Factor 1, alpha Subunit ; genetics ; metabolism ; Neurites ; drug effects ; PC12 Cells ; RNA, Messenger ; metabolism ; Rats ; Sodium Nitrite ; pharmacology ; Up-Regulation ; Vascular Endothelial Growth Factor A ; genetics ; secretion

Arsenic trioxide (ATO) has been identified as an effective treatment for acute promyelocytic leukemia (APL) but is much less effective against solid tumors such as hepatocellular carcinoma (HCC). In the search for ways to enhance its therapeutic efficacy against solid tumors, we have examined its use in combination with a novel derivative of β-elemene, N-(β-elemene-13-yl)tryptophan methyl ester (ETME). Here we report the effects of the combination on cell viability, apoptosis, the cell cycle and mitochondria membrane potential (MMP) in HCC SMMC-7721 cells. We found that the two compounds acted synergistically to enhance antiproliferative activity and apoptosis. The combination also decreased the MMP, down-regulated Bcl-2 and pro-proteins of the caspase family, and up-regulated Bax and BID, all of which were reversed by the p53 inhibitor, pifithrin-α. In addition, the combination induced cell cycle arrest at the G2/M phase and reduced tumor volume and weight in an xenograft model of nude mice. Overall, the results suggest that ETME in combination with ATO may be useful in the treatment of HCC patients particularly those unresponsive to ATO alone.

This study is to find out the induction by sodium nitrite of epithelial-mesenchymal transition (EMT) in human hepatocellular carcinoma cells, SMMC-7721. After treatment of SMMC-7721 with 0.25 - 25 mmol.L-1 sodium nitrite for 48 h, the assays used include enzyme-linked immunosorbent assay (ELISA) for evaluation of TGF-beta1, IL-6 and IL-8 level in the conditioned medium, phase-contrast microscopy for morphology observation, and scratch wound healing as well as transwell migration assays for measurement of migration and metastatic potential. Additionally, the hallmarks of EMT, p-AKT and its downstream signaling molecules were examined by Western blotting. The results showed that TGF-beta1 secreted by SMMC-7721 elevated significantly in a dose-dependent fashion, whereas the increased IL-8 and IL-6 did not show dose-dependent response. The EMT was induced by exposure of SMMC-7721 with 0.25 mmol.L-1 of sodium nitrite, which was characterized by increased level of Vimentin, decreased E-cadherin and elevated activity of migration and metastatic potential. The results suggest that sodium nitrite could induce SMMC-7721 EMT by increased secretion of TGF-beta1 and IL-8.
Cadherins ; metabolism ; Carcinoma, Hepatocellular ; metabolism ; pathology ; Cell Line, Tumor ; Cell Movement ; Dose-Response Relationship, Drug ; Epithelial-Mesenchymal Transition ; drug effects ; Humans ; Interleukin-6 ; secretion ; Interleukin-8 ; secretion ; Liver Neoplasms ; metabolism ; pathology ; NF-kappa B ; metabolism ; Neoplasm Invasiveness ; Proto-Oncogene Proteins c-akt ; metabolism ; Sodium Nitrite ; administration & dosage ; pharmacology ; Transforming Growth Factor beta1 ; secretion ; Twist-Related Protein 1 ; metabolism ; Vimentin ; metabolism

The prenatal ethanol exposure induced the alterations of dendritic spine and synapse in visual cortex and their long-term effect would be investigated in mice from P0 to P30. Pregnant mice were intubated ethanol daily from E5 through the pup's birth to establish mode of prenatal alcohol abuse. The dendritic spines of pyramidal cells in visual cortex of pups were labeled with DiI diolistic assay, and the synaptic ultrastructure was observed under transmission electron microscope. Prenatal alcohol exposure was associated with a significant decrease in the number of dendritic spines of pyramidal neurons in the visual cortex and an increase in their mean length; ultrastructural changes were also observed, with decreased numbers of synaptic vesicles, narrowing of the synaptic cleft and thickening of the postsynaptic density compared to controls. Prenatal alcohol exposure is associated with long-term changes in dendritic spines and synaptic ultrastructure. The changes were dose-dependent with long term effect even at postnatal 30.
Animals ; Dendritic Spines ; ultrastructure ; Ethanol ; toxicity ; Female ; Fetal Alcohol Spectrum Disorders ; etiology ; pathology ; Male ; Mice ; Mice, Inbred C57BL ; Microscopy, Confocal ; Microscopy, Electron, Transmission ; Pregnancy ; Prenatal Exposure Delayed Effects ; pathology ; Pyramidal Cells ; ultrastructure ; Synapses ; ultrastructure ; Visual Cortex ; ultrastructure