Objective: To investigate the effect of P62 on the migration and motility of human epidermal cell line HaCaT in high glucose microenvironment and its possible molecular mechanism, so as to explore the mechanism of refractory diabetic foot wound healing. Methods: The method of experimental research was used. HaCaT cells in logarithmic growth phase was taken for experiment. The cells were collected and divided into normal control group (culture solution containing glucose with final molarity of 5.5 mmol/L) and high glucose (culture solution containing glucose with final molarity of 30.0 mmol/L) 24 h group, high glucose 48 h group, and high glucose 72 h group according to the random number table (the same grouping method below). The cells in normal control group were routinely cultured for 72 h, cells in high glucose 72 h group were cultured with high glucose for 72 h, cells in high glucose 48 h group were routinely cultured for 24 h then cultured with high glucose for 48 h, cells in high glucose 24 h group were routinely cultured for 48 h then cultured with high glucose for 24 h. Then the protein expression of P62 was detected by Western blotting. The cells were collected and divided into normal control group and high glucose group. After being correspondingly cultured for 48 h as before, the protein expression of P62 was detected by immunofluorescence method (indicated as green fluorescence). The cells were collected and divided into negative control small interfering RNA (siRNA) group, P62-siRNA-1 group, P62-siRNA-2 group, and P62-siRNA-3 group, and transfected with the corresponding reagents. At post transfection hour (PTH) 72, the protein expression of P62 was detected by Western blotting. The cells were collected and divided into normal glucose+negative control siRNA group, normal glucose+P62-siRNA group, high glucose+negative control siRNA group, and high glucose+P62-siRNA group. After the corresponding treatment, the protein expression of P62 was detected by Western blotting at PTH 72 h, the cell migration rate was detected and calculated at 24 h after scratching by scratch test, with the number of samples being 9; and the range of cell movement was observed and the trajectory velocity was calculated within 3 h under the living cell workstation, with the number of samples being 76, 75, 80, and 79 in normal glucose+negative control siRNA group, normal glucose+P62-siRNA group, high glucose+negative control siRNA group, and high glucose+P62-siRNA group, respectively. The cells were collected and divided into normal glucose+phosphate buffered solution (PBS) group, high glucose+PBS group, and high glucose+N-acetylcysteine (NAC) group. After the corresponding treatment, the protein expression of P62 at 48 h of culture was detected by Western blotting and immunofluorescence method, respectively. Except for scratch test and cell motility experiment, the number of samples was all 3 in the rest experiments. Data were statistically analyzed with one-way analysis of variance and least significant difference test. Results: Compared with the protein expression in normal control group, the protein expressions of P62 of cells in high glucose 24 h group, high glucose 48 h group, and high glucose 72 h group were significantly increased (P<0.01). At 48 h of culture, the green fluorescence of P62 of cells in high glucose group was stronger than that in normal control group. At PTH 72, compared with the protein expression in negative control siRNA group, the protein expressions of P62 of cells in P62-siRNA-1 group, P62-siRNA-2 group, and P62-siRNA-3 group were significantly decreased (P<0.01). At PTH 72, compared with the protein expression in normal glucose+negative control siRNA group, the protein expression of P62 of cells in normal glucose+P62-siRNA group was significantly decreased (P<0.01), while the protein expression of P62 of cells in high glucose+negative control siRNA group was significantly increased (P<0.01); compared with the protein expression in high glucose+negative control siRNA group, the protein expression of P62 of cells in high glucose+P62-siRNA group was significantly decreased (P<0.01). At 24 h after scratching, compared with (55±7)% in normal glucose+negative control siRNA group, the cell migration rate in normal glucose+P62-siRNA group was significantly increased ((72±14)%, P<0.01), while the cell migration rate in high glucose+negative control siRNA group was significantly decreased ((37±7)%, P<0.01); compared with that in high glucose+negative control siRNA group, the cell migration rate in high glucose+P62-siRNA group was significantly increased ((54±10)%, P<0.01). Within 3 h of observation, the cell movement range in high glucose+negative control siRNA group was smaller than that in normal glucose+negative control siRNA group, while the cell movement range in normal glucose+P62-siRNA group was larger than that in normal glucose+negative control siRNA group, and the cell movement range in high glucose+P62-siRNA group was larger than that in high glucose+negative control siRNA group. Compared with that in normal glucose+negative control siRNA group, the cell trajectory speed in normal glucose+P62-siRNA group was significantly increased (P<0.01), while the cell trajectory speed in high glucose+negative control siRNA group was significantly decreased (P<0.01); compared with that in high glucose+negative control siRNA group, the cell trajectory speed in high glucose+P62-siRNA group was significantly increased (P<0.01). At 48 h of culture, compared with that in normal glucose+PBS group, the protein expression of P62 of cells in high glucose+PBS group was significantly increased (P<0.01); compared with that in high glucose+PBS group, the protein expression of P62 of cells in high glucose+NAC group was significantly decreased (P<0.01). At 48 h of culture, the green fluorescence of P62 of cells in high glucose+PBS group was stronger than that in normal glucose+PBS group, while the green fluorescence of P62 of cells in high glucose+NAC group was weaker than that in high glucose+PBS group. Conclusions: In HaCaT cells, high glucose microenvironment can promote the protein expression of P62; knockdown of P62 protein can promote the migration and increase the mobility of HaCaT cells; and the increase of reactive oxygen species in high glucose microenvironment may be the underlying mechanism for the increase of P62 expression.
Humans ; RNA, Small Interfering/genetics* ; Cell Line ; Epidermis ; Glucose/pharmacology* ; Epidermal Cells

OBJECTIVETo investigate the effect of high mobility group boxl (HMGBI) gene silence on adriamycin (ADM)-induced apoptosis in K562/A02 drug resistance leukemia cells.

METHODSK562/ A02 cells were transient transfected with HMGB1- small interference RNA(siRNA) vector, and the levels of HMGB1 gene differential expression pre-and post-transfection were measured by RT-PCR and Western blotting. 50% inhibition concentration (IC50) of ADM on K562/A02 was determined by WST-8 assay. Cell apoptosis was assessed by flow cytometry. The release of Smac/DIABLO from the mitochondria to the cytoplasm was assayed by Western blotting. Activity of Caspase-3 was assayed with a Caspase Colorimetric Assay Kit.

RESULTS(1) The HMGB1 expression at mRNA and protein levels in HMGB1 siRNA transfected K562/A02 cells were decreased by 86% and 71% respectively compared with control. (2) Suppression of HMGB1 by siRNA in K562/A02 cells resulted in a reversal of the resistance to ADM, and decreased IC50 from (4.83 +/- 0.08) microg/ml to (1.33 +/- 0.10) microg/ml. 1 microg/ml and 5 microg/ml of ADM treatment increased cell apoptotic rate by 27% and 32% respectively. (3) HMGB1 suppression in K562/A02 cells significantly promoted ADM- induced Smac/DIABLO release from the mitochondria to the cytoplasm, and increased the activities of Caspase-3.

CONCLUSIONHMGB1 gene silence can enhance sensitivity of K562/A02 cells to ADM and reverse cell resistant to ADM.

Apoptosis ; drug effects ; genetics ; Doxorubicin ; pharmacology ; Gene Silencing ; HMGB1 Protein ; genetics ; Humans ; K562 Cells ; RNA, Small Interfering ; genetics

OBJECTIVETo investigate the effect of small interfering RNA (siRNA) silencing Apollon gene combined with tetramethylpyrazine (TMP) on the proliferation and apoptosis of human chronic myeloid leukemia cell line K562.

METHODSK562 cells were divided into blank control, negative control, and RNA interference (RNAi) group. For the RNAi group, the pGPHI-GFP-Neo-Apollon eukaryotic expression vector based on the best Apollon siRNA fragments screened out in previous experiments was constructed; the blank control group received no treatment, and the negative control group was transfected with negative plasmid vector. The mRNA and protein expression of Apollon was measured by RT-PCR and cell immunofluorescence, respectively. Additionally, TMP (320 μg/mL) was applied to set TMP, TMP+negative control, and TMP+RNAi groups. The cell viability and apoptosis rate were determined by MTT assay and flow cytometry, respectively.

RESULTSThe constructed vector was stably expressed in K562 cells. The RNAi group had significantly lower mRNA and protein expression of Apollon than the blank control group and negative control (P<0.05). The RNAi group had significantly increased proliferation inhibition rate and apoptosis rate, as compared with the blank contorl group (P<0.05). The TMP+RNAi group had significantly increased proliferation inhibition rate and apoptosis rate, as compared with the RNAi, and TMP groups (P<0.05).

CONCLUSIONSApollon siRNA can significantly inhibit the proliferation and promote the apoptosis of K562 cells, and the addition of TMP can further increase the proliferation inhibition rate and apoptosis rate, suggesting that siRNA technology combined with drugs has a significant potential value in the treatment of leukemia.

Apoptosis ; Cell Proliferation ; Flow Cytometry ; Humans ; Inhibitor of Apoptosis Proteins ; antagonists & inhibitors ; genetics ; K562 Cells ; Pyrazines ; pharmacology ; RNA, Small Interfering ; genetics

OBJECTIVETo screen out active substances on Neuromedin U2 receptor (NMU2R) by using stable NMU2R cell lines and negative cell lines and analyzing siRNA interference.

METHODNMU2R cells were used to observe the activating effect of nine nine citrus flavonoids on NMU2R cell. Afterwards, false-positive interference of citrus flavonoids that showed higher activating effect was eliminated by using negative cells and analyzing the efficiency of siRNA interference.

RESULTHesperidin and nobiletin contained in citrus flavonoids were found to effectively activate NMU2R. The efficacy, EC50 and potency values of hesperidin were 4.688, 318.970 micromol x L(-1) and 200.933 micromol x L(-1), while the efficacy, EC50 and potency values of nobiletin were 4.758, 5.832 micromol x L(-1) and 3.124 micromol x L(-).

CONCLUSIONHesperidin and nobiletin contained in citrus flavonoids can activate NMU2R. Nobiletin shows such a low EC50 that it has medicinal value.

Cell Line ; Citrus ; chemistry ; Flavonoids ; pharmacology ; Gene Expression ; drug effects ; Humans ; Plant Extracts ; pharmacology ; RNA Interference ; drug effects ; RNA, Small Interfering ; genetics ; metabolism ; Receptors, Neurotransmitter ; genetics ; metabolism

OBJECTIVE: To investigate the changes of laryngeal cancer Hep-2 cells to cisplatin chemosensitivity after the interference of siRNA of β-catenin gene expression. METHOD: Using a small interference RNA (siRNA) technology interfere β-catenin gene of Hep-2 cells . The mRNA and protein levels of β-catenin in the Hep-2 cells of different groups were detected by qPCR and Western blot. It was divided into siRNA-β-catenin-Hep-2 siRNA group, β-catenin-Neg negative control group and blank control group. Cell proliferation inhibition rate of different concentrations of cisplatin on three groups was detected by MTT assay. Calculate the 50% inhibitory effective concentration IC50 value. Check the change of three groups of cells' apoptosis rate by flow cytometry after the same concentrations of cisplatin stimulation. RESULT: β-catenin-siRNA interference fragment can specifically reduce the expression levels of β-catenin mRNA and protein. qPCR illustrated the expression of mRNA in β-catenin-siR-NA-Hep-2 interference group decreased 70% (P < 0.05) compared with the control group, Western blot results showed that the β-catenin protein expression of interference group (0. 545 ± 0.111) decreased significantly compared with blank control group (1.507 ± 0.139) and negative control group (1.429 ± 0.089), P < 0.05. The IC50 calculation software showed that IC50 of cisplatin on β-catenin-siRNA IC50 interference group is (5.81 ± 0.46)μg/ml, the blank control group is (10.10 ± 1.01) μg/ml, the difference between the two groups has statistical signifi- cance (P < 0.01). Cell apoptosis rate of β-catenin-siRNA interference group was (26.15 ± 0.60)%, significantly higher than the control group (14.16 ± 0.05)%, P < 0.05. CONCLUSION To interfere the expression of β-catenin can effectively enhance the sensitivity of laryngeal cancer cells to chemotherapeutic drugs cisplatin. It provides a theoretical support for the reduction of laryngeal cancer chemotherapy drug cisplatin dosage.
Apoptosis ; Cell Line, Tumor ; Cisplatin ; pharmacology ; Drug Resistance, Neoplasm ; Humans ; Laryngeal Neoplasms ; genetics ; RNA Interference ; RNA, Messenger ; RNA, Small Interfering ; beta Catenin ; genetics

The study is aimed to confirm the silencing efficiency of the vector in human hepatocellular liver carcinoma cell line (HepG2), and observe effects of AMPKgamma silencing on the AMPK stimulating activity and lipid synthesis of cordycepin (CCS), a natural product with known AMPK activating function. The downregulating efficacy of siRNAs on AMPKgamma expression was confirmed in our previous study. The double stranded shRNA Oligo was ligated to lentivirus vector and verified by sequencing. The lentiviral which can effectively inhibited protein expression levels of AMPKgamma was selected by Western blotting, and the regulation of CCS on protein expression of AMPKgamma and p-AMPK in AMPKgamma silence cells were detected by Western blotting analysis. The lipid accumulation in cells was observed by Oil-Red O stain and cells were collected for the estimation of cholesterol (TC), triglyceride (TG). The results showed that the lentiviral vector carrying a shRNA targeting the AMPKgamma gene was successfully constructed. Western blotting analysis confirmed that GR085 had the highest interfering efficiency. Treatment with CCS can significantly increase the levels of phospho-AMPK in normal cells, and the level of TC, TG was reduced, but in AMPKgamma silence cells the effects of CCS on AMPK activation and lipid synthesis were almost completely abolished without changing the expression levels of total AMPK or AMPKgamma protein. In conclusion, the AMPKgamma gene may be related to AMPK activation and intracellular lipids regulation by CCS.
AMP-Activated Protein Kinases ; genetics ; metabolism ; Cholesterol ; metabolism ; Deoxyadenosines ; pharmacology ; Genetic Vectors ; HEK293 Cells ; Humans ; Lentivirus ; genetics ; Phosphorylation ; RNA Interference ; RNA, Small Interfering ; genetics ; Triglycerides ; metabolism

OBJECTIVETo delineate the effects of HBV X gene and of As(2)O(3) on p53 expression and activity in HepG2 cells by shRNA-mediated RNA interference (RNAi).

METHODSHepG2 cells and cells with stable expression of HBV X gene, HepG2-X, were treated with 2 micromol/L As(2)O(3), and the corresponding untreated cells were used as controls. Cell and nuclear lysates were extracted. Total level and the relative activity absorbance of p53 were detected by modified ELISA. HBV X gene sequence-specific shRNA expression vectors, Xi-S1 and Xi-S2, and sequence-unrelated control Xi-S3 were transfected into HepG2-X. The effect of As(2)O(3) on p53 expression and activity were retested.

RESULTSTotal p53 level was up-regulated and its relative activity ratio was enhanced by As(2)O(3) in HepG2 and HepG2-X cells. The total p53 level induced by As(2)O(3) was further up-regulated by HBX expression, while its relative activity was significantly suppressed. The suppression was removed after HBX expression was suppressed by shRNA.

CONCLUSIONAs(2)O(3) could up-regulate p53 expression and enhance its activity. shRNA-mediated RNA interference is conveniently being used in studies on the effect of HBV X gene expression on p53 expression and activity. HBV X expression could up-regulate p53 gene expression level induced by As(2)O(3), while it suppressed the activity of p53.

Apoptosis ; Arsenicals ; pharmacology ; Gene Expression ; Hep G2 Cells ; Hepatitis B virus ; genetics ; Humans ; Oxides ; pharmacology ; RNA, Small Interfering ; Trans-Activators ; genetics ; Tumor Suppressor Protein p53 ; genetics ; metabolism

Small interference RNA (siRNA) induced RNA interference (RNAi) technology has shown high specificity and high efficiency of silencing target gene expression, and it is becoming a promising candidate drug for the therapy of cancer and viral infection diseases. At present, the lack of safe and effective carrier materials and delivery systems of siRNA through extracellular and intracellular barriers still hampers the clinical application. In order to overcome this difficulty, we proposed using chitosan, naturally occurring polycation, to form complex siRNA against green fluorescence protein (siRNA-eGFP). The spherical and stable chitosan-siRNA nanoparticles with 83%-94% siRNA complex efficiency can be formulated under mild electrostatic interaction. The size and Zeta potential of nanoparticles were within the range of 90-180 nm and 10-30 mV, respectively. 80% cell viability could be maintained inthe course of incubating with chitosan-siRNA nanoparticles. Moreover, nearly 80% gene silencing efficiency of chitosan-siRNA nanoparticles was realized.
Cell Line ; Chitosan ; pharmacology ; Drug Carriers ; chemistry ; Drug Delivery Systems ; Green Fluorescent Proteins ; chemistry ; Humans ; Nanoparticles ; RNA Interference ; RNA, Small Interfering ; genetics ; pharmacology

In order to investigate the potential role of human ERMAP gene in erythropoiesis, the ERMAP-dsDNA was designed, ERMAP-shRNA expressing plasmids was constructed, and ERMAP-shRNA/K562 cell was established. Cell morphology, biphenylamine staining, expression of cell surface antigens as well as quantitative level of human ERMAP gene were observed during K562 cells differentiating toward erythroid lineage induced by Ara-C. The results showed that at 72 hours after Ara-C treatment, ERMAP-shRNA/K562 cell size became large with increasing cytoplasm content. The percentage of biphenylamine positive cells increased from 1.17% to 2.04% (p < 0.05), but still lower than that in group K562 + Ara-C. The percentage of CD36(-)/CD235a(+) increased from 8.83% to 11.28%, CD36(+)/CD235a(+) increased from 1.23% to 2.64%, and CD36(+)/CD235a(-) increased from 0.59% to 1.47% respectively, which were all lower than that in group K562 + Ara-C at either time point. At the same time, the level of ERMAP expression increased slowly from 2.52 x 10(-3) to 4.53 x 10(-3), which was also significantly lower than that of group K562 + Ara-C. It is concluded that the ERMAP-shRNA inhibits the Ara-C-induced erythroid differentiation of K562 cells, which further suggests that there is relationship between hERMAP and erythroid differentiation and development.
Blood Group Antigens ; genetics ; Butyrophilins ; Cell Differentiation ; drug effects ; Cytarabine ; pharmacology ; Erythropoiesis ; drug effects ; Humans ; K562 Cells ; RNA, Messenger ; RNA, Small Interfering ; pharmacology

The evolutionarily conserved RNA Polymerase II Rpb4/7 sub-complex has been thoroughly studied in yeast and impacts gene expression at multiple levels including transcription, mRNA processing and decay. In addition Rpb4/7 exerts differential effects on gene expression in yeast and Rpb4 is not obligatory for yeast (S. cerevisiae) survival. Specialised roles for human (hs) Rpb4/7 have not been extensively described and we have probed this question by depleting hsRpb4/7 in established human cell lines using RNA interference. We find that Rpb4/7 protein levels are inter-dependent and accordingly, the functional effects of depleting either protein are co-incident. hsRpb4/7 exhibits gene-specific effects and cells initially remain viable upon hsRpb4/7 depletion. However prolonged hsRpb4/7 depletion is cytotoxic in the range of cell lines tested. Protracted cell death occurs by an unknown mechanism and in some cases is accompanied by a pronounced elongated cell morphology. In conclusion we provide evidence for a gene-specific role of hsRpb4/7 in human cell viability.
Cell Line ; Cell Nucleus ; metabolism ; Cell Survival ; drug effects ; Gene Expression Profiling ; HeLa Cells ; Humans ; RNA Interference ; RNA Polymerase II ; antagonists & inhibitors ; genetics ; metabolism ; RNA, Small Interfering ; pharmacology