The aim of this study was to observe the inhibitory effect of daunorubicin on KG1a cells and the expression of Eps8 which is a novel tumor-associated antigen with its full name epidermal growth factor receptor pathway substrate 8 (Eps8), and to explore the effect of daunorubicin on Eps8 expression in KG1a cells at mRNA and protein levels. The KG1a cells were treated with different concentration of daunorubicin for 24, 48, 72 h, then trypan blue staining was used to detect the inhibitory rate of KGla cells, RQ-PCR and Western blot were used to detect Eps8 mRNA and Eps8 protein expression. The results showed that daunorubicin inhibited the proliferation of KG1a cells in a dose and time dependent manner (r = 0.983, P < 0.01). Daunorubicin could reduce the mRNA and protein levels of Eps8 expression in dose and time dependent manners in KG1a cells (r = 0.979, P < 0.05). It is concluded that with the increasing of concentration and time of daunorubicin acting on KG1a cells, the cell proliferative inhibitory effect increased and the expression of Eps8 decreased, suggesting that the inhibitory effect of daunorubicin on KG1a cell proliferation is realized through downregulation of Eps8 expression.
Adaptor Proteins, Signal Transducing ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Daunorubicin ; pharmacology ; Humans

The purpose of this study was to compare the differences of the protein expression profiles between human myeloid leukemia K562 cells and adriamycin-resistant K562/A02 cells, as well as to select novel resistance-related proteins in myeloid leukemia by means of proteomics. The total cellular proteins were separated from K562 and adriamycin-resistant K562/A02 cells by using technique of two dimensional difference in gel electrophoresis (2D-DIGE). Differentially expressed proteins were analyzed by matrix-assisted laser desorption ionization/time of flight-mass spectrometry (MALDI-TOF/MS), and by protein database searching. Moreover, the differentially expressed proteins were verified at protein and mRNA levels by Western blot assay and quantitative real time PCR. The results showed that 8 proteins differentially expressed in adriamycin-resistant K562/A02 cells, among them 2 proteins were identified to be down-regulated and 6 to be up-regulated. These identified proteins involved in the cell energy metabolism, cell proliferation, cell apoptosis, signal transduction, gene transcription and translation respectively. The results assayed by Western blot were similar to those detected by 2D-PAGE. Two up-regulated proteins Stathmin and CrkL were selected for verification in K562 and K562/A02 cells. As a result, the results detected by Western blot were identical with results from 2D-DIGE; real time quantitative PCR assay showed that the changes of CrkL at mRNA level were identical with changes at protein level, but no complete identity of Stathmin changes at mRNA level and protein level was observed. It is concluded that the difference of protein expression profile exists in K562 and K562/A02 cells. Stathmin and CrkL proteins may be involved in the drug resistance and suggest a novel clue for the resistant mechanisms in myeloid leukemia, which is worth further to explore.
Adaptor Proteins, Signal Transducing ; metabolism ; Doxorubicin ; pharmacology ; Drug Resistance, Neoplasm ; Humans ; K562 Cells ; Leukemia ; metabolism ; Nuclear Proteins ; metabolism ; Stathmin ; metabolism

Objective To study the effects of TYRO protein kinase-binding protein (TYROBP) deficiency on learning behavior, glia activation and pro-inflammatory cycokines, and Tau phosphorylation of a new Alzheimer's disease (AD) mouse model carrying a PSEN1 p.G378E mutation.Methods A new AD mouse model carrying PSEN1 p.G378E mutation was built based on our previously found AD family which might be ascribed to the PSEN1 mutation, and then crossed with TYROBP deficient mice to produce the heterozygous hybrid mice (PSEN1^G378E/WT; Tyrobp^+/-) and the homozygous hybrid mice (PSEN1^G378E/G378E; Tyrobp^-/-). Water maze test was used to detect spatial learning and memory ability of mice. After the mice were sacrificed, the hippocampus was excised for further analysis. Immunofluorescence was used to identify the cell that expresses TYROBP and the number of microglia and astrocyte. Western blot was used to detect the expression levels of Tau and phosphorylated Tau (p-Tau), and ELISA to measure the levels of pro-inflammatory cytokines. Results Our results showed that TYROBP specifically expressed in the microglia of mouse hippocampus. Absence of TYROBP in PSEN1^G378E mutation mouse model prevented the deterioration of learning behavior, decreased the numbers of microglia and astrocytes, and the levels of interleukin-6, interleukin-1β and tumor necrosis factor-α in the hippocampus (all P < 0.05). The ratios of AT8/Tau5, PHF1/Tau5, pT181/Tau5, pT231/Tau5 and p-ERK/ERK were all higher in homozygous hybrid mice (PSEN1^G378E/G378E; Tyrobp^-/- mice) compared with PSEN1^G378E/G378E mice (all P < 0.05). Conclusions TYROBP deficiency might play a protective role in the modulation of neuroinflammation of AD. However, the relationship between neuroinflammation processes involving microglia and astrocyte activation, and release of pro-inflammatory cytokines, and p-Tau pathology needs further study.
Mice ; Animals ; Alzheimer Disease/genetics* ; Neuroinflammatory Diseases ; Hippocampus/pathology* ; Mutation ; Cytokines/pharmacology* ; Disease Models, Animal ; tau Proteins/pharmacology* ; Amyloid beta-Peptides/metabolism* ; Adaptor Proteins, Signal Transducing/pharmacology*

Retinoic acid plays an important role in maintaining the structure and function in male testis. Recent studies showed that there is a group of genes that can be specially activated by retinoic acid during the development of male reproductive gland. The gene Stra 8 (Stimulated by Retinoic Acid) was one of the gene in this group. In mouse, Stra 8 is restrictively expressed in male germ line cells, and its function is related to the development of sperm. In order to investigate the feature of Stra 8 gene expression,the 1.4 kb (-1407 - +7) promoter region of Stra 8 gene was amplified from mouse genomic DNA. The DNA fragment was then cloned into a promoter less vector to form the construct that contained the 1.4 kb promoter region, and the reporter gene of EGFP that was regulated by 1.4kb Stra 8 promoter. To investigate the specificity of Stra 8 promoter,the vector pStro-EGFP was transfected into undifferentiated mouse stem cells such as ES-129, bone marrow mesenchymal stem cell (mMSC) and spermatogonial stem cell (mSSC). The results showed that the expression of GFP was only observed in the mSSC cells,which indicated that Stra 8 gene was specially regulated in testis tissue. As the gene marker,vector pStra8-EGFP was then transfected to undifferentiated mMSC cells. After being selected by G418 for 2 weeks,the mMSC cells were induced by retinoic acid. After 12 hours induction, some induced cells started to express GFP protein, which was observed under the fluorescence microscope. At the same time, several stem cell specificity biomarkers such as Oct4, and spermatogonial stem cell biomarkers such as CyclinA2 and Stra 8 were detected in the induced cells by RT-PCR method. These results showed that the mMSCs would differentiated to spermatognial stem cells after induced by Retinoic Acid.
Adaptor Proteins, Signal Transducing ; Animals ; Cell Differentiation ; genetics ; Cells, Cultured ; Gene Expression ; Male ; Mice ; Promoter Regions, Genetic ; Proteins ; genetics ; Spermatogonia ; cytology ; metabolism ; Stem Cells ; cytology ; metabolism ; Tretinoin ; pharmacology

To investigate the effect of berberine on insulin secretion of NIT-1 cells stimulated by glucose and the possible molecular mechanism, we used radioimmunoassay, scintillation counting technique, enzymatic method and Western blotting to measure the effects of berberine on insulin secretion, glucose utilization, the activity of glucokinase (GK) and protein level of GK and GK regulation protein (GKRP). Compared with untreated group, insulin secretion level, glucose utilization, the activity and protein level of GK in NIT-1 cells stimulated by high concentration of glucose were increased significantly in berberine group (P < 0.05), while the protein level of GKRP in berberine group decreased markedly. In conclusion, berberine can promote insulin secretion of NIT-1 cells induced by high concentration of glucose. The possible molecular mechanism may be associated with berberine acting as a GK activator, improving glucose utilization, enhancing the activity and protein expression level of GK, as well as decreased the protein level of GKRP.
Adaptor Proteins, Signal Transducing ; metabolism ; Animals ; Berberine ; pharmacology ; Cell Line ; Glucokinase ; metabolism ; Glucose ; metabolism ; Insulin ; secretion ; Insulin-Secreting Cells ; metabolism ; secretion ; Mice

OBJECTIVETo study the role of adaptor protein Dok6 in neurite outgrowth in PC12 cells.

METHODSSeries of fusion clones were constructed by fusing different domains of Dok6 into mutant TrkC/Y516F. These constructs were transiently transfected into PC12 cells separately and the expression levels of fusion proteins were detected by Western blot. Neurite outgrowth in these PC12 cells was tested after stimulation of NT-3.

RESULTSEach fusion clone was stably expressed in PC12 cells. The fusion clones that fused both TrkC/Y516F-Dok6 (PTB+C) and TrkC/Y516F-Dok6C rescued the loss of neurite outgrowth in PC12 cells resulting from the mutation in tyrosine 516, while fusion clones that fused with single TrkC/Y516F-Dok6PTB did not show such effect.

CONCLUSIONDok6 can promote neurite outgrowth induced by NT-3 stimulation through its C-terminal in TrkC-positive PC12 cells.

Adaptor Proteins, Signal Transducing ; genetics ; metabolism ; Animals ; Neurites ; drug effects ; physiology ; Neurotrophin 3 ; pharmacology ; PC12 Cells ; Rats ; Receptor, trkC ; metabolism ; Transfection

This study was aimed to investigate the effect of bortezomib alone or combined with arsenic trioxide on the apoptosis of Jurkat cells and expression of livin mRNA. The Jurkat cells were cultured and treated with different concentrations of bortezomib, arsenic trioxide or their combination for 24 hours. Then, the expression of livin mRNA was detected by RT-PCR, the cell proliferation was analyzed with MTT assay and flow cytometry. The results showed that 5 - 25 nmol/L bortezomib could effectively inhibit Jurkat cells in a dose-dependent manner, the group of bortezomib combined with arsenic trioxide showed more inhibitory effect on Jurkat cells than the effect of bortezomib alone or arsenic trioxide alone on Jurkat cells. The expression of livin mRNA in Jurkat cells decreased in a dose-dependent manner after treated with bortezomib, which was downregulated significantly after combined treatment. It is concluded that bortezomib and arsenic trioxide can induce apoptosis by inhibiting the expression of livin mRNA in Jurkat cells. The combination of bortezomib with arsenic trioxide displays a synergistic effect.
Adaptor Proteins, Signal Transducing ; genetics ; metabolism ; Apoptosis ; drug effects ; Arsenicals ; pharmacology ; Boronic Acids ; administration & dosage ; pharmacology ; Bortezomib ; Humans ; Inhibitor of Apoptosis Proteins ; genetics ; metabolism ; Jurkat Cells ; Neoplasm Proteins ; genetics ; metabolism ; Oxides ; pharmacology ; Pyrazines ; administration & dosage ; pharmacology ; RNA, Messenger ; genetics

OBJECTIVETo explore the effect of arsenic trioxide (As2O3) on the growth inhibition of imatinib (IM)-resistant bcr-abl mutant cell lines in vitro.

METHODSCell growth of one IM-sensitive cell line, 32Dp210 and 15 IM-resistant cell lines including T315I and other 14 bcr-abl mutants were detected by MTT assay after treatment with IM and As2O3. The cell lines with 5 frequently observed mutants in CML patients were analyzed for apoptosis by flow cytometry with Annexin V and PI staining as well as the expression of bcr-abl fusion protein, phosphorylated CRKL protein and apoptosis-related proteins by Western blot.

RESULTSThe fifty percent inhibition concentration (IC50) values of As2O3 for 15 IM-resistant cell lines were 2.6-5.3 fold lower than that for IM-sensitive cell line. For the 5 bcr-abl mutants frequently happened in CML patients, As2O3 significantly inhibited the expression of bcr-abl fusion protein and phosphorylated CRKL and induced apoptosis in a dose-dependent manner as compared with that for 32Dp210. Coincidently, the cell apoptosis was induced through caspase-3, 8 and 9 pathways.

CONCLUSIONAs2O3 remarkably inhibits cell growth and induces apoptosis of IM-resistant bcr-abl mutant cell lines in vitro, suggesting that it might be a potential therapeutic agent for IM-resistant CML patients.

Adaptor Proteins, Signal Transducing ; metabolism ; Apoptosis ; drug effects ; Arsenicals ; pharmacology ; Benzamides ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Drug Resistance, Neoplasm ; Fusion Proteins, bcr-abl ; genetics ; metabolism ; Humans ; Imatinib Mesylate ; Mutation ; Nuclear Proteins ; metabolism ; Oxides ; pharmacology ; Piperazines ; pharmacology ; Pyrimidines ; pharmacology

Adaptor Proteins, Signal Transducing ; analysis ; Apoptosis ; drug effects ; Female ; Humans ; Inhibitor of Apoptosis Proteins ; analysis ; Male ; Neoplasm Proteins ; analysis ; PTEN Phosphohydrolase ; analysis ; Retinal Neoplasms ; drug therapy ; Retinoblastoma ; drug therapy ; Topoisomerase I Inhibitors ; pharmacology ; Topotecan ; pharmacology

This study was aimed to investigate the changes of silencer of death domains (SODD), survivin, caspase 3, caspase 8 and caspase 9 in the apoptotic process of human leukemia cells induced by chemotherapeutic drugs in order to explore the molecular mechanism of apoptotic modulatory genes and to search for the new target of chemotherapeutic drugs. After Jurkat cells were induced by chemotherapeutic drugs, the translocated phosphatidylserine was labeled with annexin V/PI, and the apoptosis incidence was measured by FCM; The expression changes of SODD, caspase 3, caspase 8 and caspase 9 were determined by Western blot; the changes of survivin mRNA and protein were determined by RT-PCR and immunohistochemistry SABC method respectively. The results indicated that high expressions of SODD and survivin could inhibit apoptotic signaling pathway; VCR down-regulated the function of SODD protein and effectively induced the apoptosis of Jurkat cells in a time-dependent manner and activates caspase 3 through the death receptor-mediated activation of caspase 8, in which caspase 9 and survivin were not degraded. It is concluded that SODD participates in the apoptotic process induced by VCR which induces the Jurkat cell apoptosis by downregulating expression of SODD protein and priming death receptor pathway. In the apoptotic process, the mitochondrion apoptotic pathway is not trigged.
Adaptor Proteins, Signal Transducing ; metabolism ; Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Caspase 8 ; metabolism ; Caspase 9 ; metabolism ; Humans ; Inhibitor of Apoptosis Proteins ; Jurkat Cells ; Microtubule-Associated Proteins ; metabolism ; Vincristine ; pharmacology