Lnc-HUR1 is an HBV-related long non-coding RNA, which can promote the proliferation of hepatoma cells and the occurrence and development of liver cancer. In this study we explored the effect of lnc-HUR1 on the apoptosis of hepatocellular carcinoma cells by taking the approach of immunoblotting, quantitative real time PCR, luciferase reporter assay, chromatin immunoprecipitation (ChIP) and flow cytometry. We found that overexpression of lnc-HUR1 significantly reduced the activity of caspase3/7 and the cleavage of PARP-1, while knocking down of lnc-HUR1 significantly increased the activity of caspase3/7 and promoted the cleavage of PARP-1 in HepG2 cells treated with TGF-β, pentafluorouracil or staurosporine. Consistently, the data from Annexin-V/PI staining showed that overexpression of lnc-HUR1 inhibited apoptosis, while knockdown of lnc-HUR1 promoted apoptosis. Moreover, overexpression of lnc-HUR1 up-regulated the apoptosis inhibitor Bcl-2 and down-regulated the pro-apoptotic factor BAX at both RNA and protein levels. In the CCL4-induced acute liver injury mice model, the expression of Bcl-2 in the liver tissue of lnc-HUR1 transgenic mice was higher than that of the control mice. The data from ChIP assay indicated that lnc-HUR1 reduced the enrichment of p53 on Bcl-2 and BAX promoters. All these results indicated that lnc-HUR1 inhibited the apoptosis by promoting the expression of apoptosis inhibitor Bcl-2 and inhibiting the expression of apoptosis promoting factor BAX. Further studies showed that lnc-HUR1 regulated the transcription of Bcl-2 and BAX in HCT116 cells, but had no effect on the expression of Bcl-2 and BAX in HCT116 p53^-/- cells, indicating that lnc-HUR1 regulates the transcription of Bcl-2 and BAX dependent upon the activity of p53. In conclusion, HBV upregulated lnc-HUR1 can inhibit the apoptosis of hepatoma cells. Lnc-HUR1 inhibits apoptosis by inhibiting the transcriptional activity of p53. These results suggest that lnc-HUR1 plays an important role in the occurrence and development of HBV-related hepatocellular carcinoma.
Animals ; Annexins/pharmacology* ; Apoptosis ; Carcinoma, Hepatocellular/genetics* ; Cell Proliferation ; Hep G2 Cells ; Hepatitis B virus/metabolism* ; Humans ; Liver Neoplasms/genetics* ; Mice ; Poly(ADP-ribose) Polymerase Inhibitors/pharmacology* ; Proto-Oncogene Proteins c-bcl-2/pharmacology* ; RNA, Long Noncoding/metabolism* ; Staurosporine/pharmacology* ; Transforming Growth Factor beta/pharmacology* ; Tumor Suppressor Protein p53/pharmacology* ; bcl-2-Associated X Protein/pharmacology*

OBJECTIVE: The effects of the staurosporine on contraction of self-assembled constructs and extracellular matrix syntheses of goat temporomandibular joint discs were investigated. METHODS: Goat temporomandibular joint disc cells were isolated and cultured to P3, and 5.5×10⁶ cells were combined with different concentrations of staurosporine (0, 0.1, 1, 10, 100 nmol·L⁻¹) in agarose wells and cultured for one week. The samples were frozen and sectioned. Safranin-O,  Picro-sirius red and immunohistochemical staining were performed to observe the distributions of the extracellular matrix and the expression of alpha-smooth muscle actin (α-SMA). Enzyme linked immunosorbent assay (ELISA) and Blyscan kits were utilized to quan--titatively detect the contents of type Ⅰ collagen (ColⅠ) and glycosaminoglycans (GAGs). RESULTS: Each group of goat temporo-mandibular joint disc cells in the agarose wells were gathered to self-assemble into a disc-shaped base for 4 hours and then to gradually contract into a round shape. The Picro-sirius red staining was strong and indicated collagen distribution. The Safranin-O staining observed GAGs throughout the entire construct. The expression of ColⅠ was strongly posi-tive in the staurosporine groups; however, the expression of α-SMA was weak. ColⅠ and GAGs contents in the stau-rosporine groups were greater than that of the control group, especially in the 10 nmol·L⁻¹ group (P<0.01). CONCLUSIONS Staurosporine has a certain effect on the shrinkage of self-assembled constructs; however, such effect is not prominent. Staurosporine contributes to the construction synthesis of extracellular matrix.
Animals ; Collagen Type I ; Glycosaminoglycans ; Goats ; Staurosporine ; pharmacology ; Temporomandibular Joint ; Temporomandibular Joint Disc ; cytology ; drug effects

Actin cytoskeleton has been known to control and/or be associated with chondrogenesis. Staurosporine and cytochalasin D modulate actin cytoskeleton and affect chondrogenesis. However, the underlying mechanisms for actin dynamics regulation by these agents are not known well. In the present study, we investigate the effect of staurosporine and cytochalasin D on the actin dynamics as well as possible regulatory mechanisms of actin cytoskeleton modulation. Staurosporine and cytochalasin D have different effects on actin stress fibers in that staurosporine dissolved actin stress fibers while cytochalasin D disrupted them in both stress forming cells and stress fiber-formed cells. Increase in the G-/F-actin ratio either by dissolution or disruption of actin stress fiber is critical for the chondrogenic differentiation. Cytochalasin D reduced the phosphorylation of cofilin, whereas staurosporine showed little effect on cofilin phosphorylation. Either staurosporine or cytochalasin D had little effect on the phosphorylation of myosin light chain. These results suggest that staurosporine and cytochalasin D employ different mechanisms for the regulation of actin dynamics and provide evidence that removal of actin stress fibers is crucial for the chondrogenic differentiation.
Actin Cytoskeleton/*drug effects ; Actins/metabolism ; Animals ; Cell Differentiation/*drug effects ; Cells, Cultured ; Chickens ; Chondrogenesis/*drug effects ; Cytochalasin D/*pharmacology ; Mesoderm/cytology/drug effects ; Myosin Light Chains/metabolism ; Nucleic Acid Synthesis Inhibitors/*pharmacology ; Phosphorylation ; Staurosporine/*pharmacology ; Stress Fibers/drug effects

OBJECTIVETo investigate the effects of staurosporine (ST) on the proliferation and apoptosis of prostate cancer PC-3 cells.

METHODSProstate cancer PC-3 cells were treated in vitro with ST at 10(-8) mol/L. The expressions of cyclin A and cyclin D1 proteins in the cells were detected by Western blot, the effect of ST on the proliferation of the cells determined by MTT assay and plate colony formation, the apoptosis of the cells examined by flow cytometry, and their morphological changes observed under the light microscope.

RESULTSST treatment markedly decreased the expressions of cyclin A and cyclin D1 in the PC-3 cells, and significantly inhibited the growth of the PC-3 cells (19.35%) at 48 h. (F = 31.06, P < 0.01). The colony formation rate of the PC-3 cells was (37.10 +/- 3.43) % in the ST group, significantly lower than (64.80 +/- 4.34) % in the control (chi2 = 14.59, P < 0.05) and (62.80 +/- 4.36) % in the DMSO group (chi2 = 12.50, P < 0.05), while the apoptosis rate of the cells was remarkably higher in the ST group ([19.6 +/- 2.20] %) than in the control ([5.33 +/- 1.40] %) and the DMSO group ([5.50 +/- 0.96] %) (F = 104.36, P < 0.01). Under the light microscope, the ST-treated cells were round with indistinct margins as compared with those of the other two groups.

CONCLUSIONST could significantly inhibit the proliferation and induce the apoptosis of PC-3 cells.

Apoptosis ; drug effects ; Cell Line, Tumor ; drug effects ; Cell Proliferation ; drug effects ; Humans ; Male ; Prostatic Neoplasms ; pathology ; Staurosporine ; pharmacology

Neurotrophins protect neurons against excitotoxicity; however the signaling mechanisms for this protection remain to be fully elucidated. Here we report that activation of the phosphatidyl inositol 3 kinase (PI3K)/Akt pathway is critical for protection of hippocampal cells from staurosporine (STS) induced apoptosis, characterized by nuclear condensation and activation of the caspase cascade. Both nerve growth factor (NGF) and brain-derived growth factor (BDNF) prevent STS-induced apoptotic morphology and caspase-3 activity by upregulating phosphorylation of the tropomyosin receptor kinase (Trk) receptor. Inhibition of Trk receptor by K252a altered the neuroprotective effect of both NGF and BDNF whereas inhibition of the p75 neurotrophin receptor (p75NTR) had no effect. Impairment of the PI3K/Akt pathway or overexpression of dominant negative (DN)-Akt abolished the protective effect of both neurotrophins, while active Akt prevented cell death. Moreover, knockdown of Akt by si-RNA was able to block the survival effect of both NGF and BDNF. Thus, the survival action of NGF and BDNF against STS-induced neurotoxicity was mediated by the activation of PI3K/Akt signaling through the Trk receptor.
Animals ; Apoptosis/*drug effects ; Brain-Derived Neurotrophic Factor/*metabolism ; Cell Line ; Cell Survival/drug effects ; Cytoprotection/*drug effects ; Gene Knockdown Techniques ; Hippocampus/*cytology ; Nerve Growth Factor/*metabolism ; Neurons/*cytology/drug effects/metabolism ; PC12 Cells ; Proto-Oncogene Proteins c-akt/metabolism ; Rats ; Receptors, Nerve Growth Factor/metabolism ; Signal Transduction/drug effects ; Staurosporine/*pharmacology

OBJECTIVETo observe the change of the neuropeptide pro-protein processing system in the ischemic retina ganglion cell-5 (RGC-5) cells, pro-protein convertase-2 (PC2), carboxypeptidase-E (CPE) and preproneuropeptide Y (preproNPY) protein levels in the ischemic RGC-5 cells and conditioned medium were analyzed.

METHODSThe RGC-5 cell was differentiated in 0.1 mumol/L staurosporine for 24 h and then stressed by different doses of oxygen and glucose deprivation (OGD). The acute or chronic OGD-induced cell death rates were obtained by using PI or TUNEL staining. The protein expression levels were determined by using the Western blot method and PC2 activity analysis.

RESULTSThe ischemia caused substantial cell death in an OGD dose-dependent manner. In the cells, proPC2 and preproNPY protein levels gradually increased whereas proCPE gradually decreased. After OGD, PC2 activity was decreased. In the conditioned medium, proPC2 and PC2 proteins gradually decreased whereas proCPE, CPE, and preproNPY proteins gradually increased.

CONCLUSIONThese results demonstrated that OGD inhibited the neuropeptide pro-protein processing system by reducing PC2 activity and the maturation of proPC2. The aggregation of the pro-proteins and the increase of the active CPE excision adversely exacerbated the cell injury. The pro-protein processing system might play a critical role in the ischemic stress of RGC-5 cells.

Animals ; Carboxypeptidase H ; metabolism ; Cell Death ; drug effects ; physiology ; Cell Differentiation ; drug effects ; Cell Hypoxia ; drug effects ; physiology ; Cell Line, Transformed ; Enzyme Inhibitors ; pharmacology ; Gene Expression Regulation, Enzymologic ; drug effects ; physiology ; Glucose ; deficiency ; In Situ Nick-End Labeling ; methods ; Indoles ; Neuropeptide Y ; metabolism ; Proprotein Convertase 2 ; metabolism ; Protein Precursors ; metabolism ; Rats ; Retinal Ganglion Cells ; drug effects ; metabolism ; Staurosporine ; pharmacology ; Time Factors

Differentiation of neuronal cells has been shown to accelerate stress-induced cell death, but the underlying mechanisms are not completely understood. Here, we find that early and sustained increase in cytosolic ([Ca2+]c) and mitochondrial Ca2+ levels ([Ca2+]m) is essential for the increased sensitivity to staurosporine-induced cell death following neuronal differentiation in PC12 cells. Consistently, pretreatment of differentiated PC12 cells with the intracellular Ca2+-chelator EGTA-AM diminished staurosporine-induced PARP cleavage and cell death. Furthermore, Ca2+ overload and enhanced vulnerability to staurosporine in differentiated cells were prevented by Bcl-XL overexpression. Our data reveal a new regulatory role for differentiation-dependent alteration of Ca2+ signaling in cell death in response to staurosporine.
Animals ; Calcium/*metabolism ; Caspase 3/metabolism ; Cell Differentiation/*physiology ; DNA Fragmentation ; Mitochondria/metabolism ; *Neurons/cytology/drug effects/physiology ; *PC12 Cells/cytology/drug effects/physiology ; Rats ; Staurosporine/*pharmacology ; bcl-X Protein/metabolism

To investigate Bax translocation from cytosol into mitochondria induced by staurosporine (STS) in GFP-Bax-tagged MCF7 stable cell line, the viability was measured by MTT method. Bax translocation from cytosol into mitochondria was investigated under the fluorescence microscope. The dose-effect and time-course relationships were also observed and the percentage of GFP-Bax punctuate cells were calculated. Immunofluoresence method was used to observe Bax translocation to mitochondria, Cyt-c release from mitochondria and Annexin V label. The TMRE assay was used to investigate membrane pertential (Deltapsim) and function of mitochondria. Western blotting was used to observe the mechanism of apoptosis induced by STS. The results showed that STS can induce Bax translocation from cytoplasm to mitochondria, Cyt-c release from mitochondria and Annexin V label. The Western blotting analysis presented the inhibitory effect on apoptosis induced by STS of SP600125 which is a specific JNK inhibitor. The study revealed the mechanism of STS induced apoptosis associated with JNK activated pathway.
Anthracenes ; pharmacology ; Apoptosis ; drug effects ; Cell Line, Tumor ; Cytochromes c ; metabolism ; Cytosol ; metabolism ; Humans ; MAP Kinase Kinase 4 ; antagonists & inhibitors ; Membrane Potentials ; drug effects ; Mitochondria ; metabolism ; Protein Transport ; drug effects ; Staurosporine ; pharmacology ; bcl-2-Associated X Protein ; metabolism

Animals ; Antineoplastic Agents ; pharmacology ; therapeutic use ; Cell Cycle ; drug effects ; physiology ; Cyclin-Dependent Kinases ; antagonists & inhibitors ; metabolism ; Cyclins ; metabolism ; Flavonoids ; pharmacology ; therapeutic use ; Humans ; Neoplasms ; drug therapy ; metabolism ; pathology ; Piperidines ; pharmacology ; therapeutic use ; Purines ; pharmacology ; therapeutic use ; Staurosporine ; analogs & derivatives ; pharmacology ; therapeutic use

Protein kinase Cdelta (PKCdelta) is a member of protein kinase C family, which possess phospholipid-dependent serine and threonine kinase activity. PKCdelta is a potential drug target of diabetes and some cancers. The abnormal activation of PKCdelta can arouse diabetes and some cancers. Therefore the specific inhibitors of PKCdelta can be applied in the research and development of the drug candidate of these diseases. The present aim is to obtain active recombinant PKCdelta from COS1 cells. For cloning of mouse PKCdelta a pair of specific primers were designed based on the published sequence of this gene. The cDNA of full coding region was obtained by RT-PCR. The amplified cDNA was subsequently cloned into FLAG-tagged pcDNA3.0 and its sequence was confirmed by DNA sequencing analysis. FLAG-tagged pcDNA3.0-PKCdelta was transfected into COS1 cells. A cell strain which can stably express PKCdelta was obtained by G418 screening. FLAG-tagged PKCdelta in the supernant of COS1 cells extracts was absorbed by anti-FLAG resin and eluted by FLAG peptide. The purified protein appeared as a single band on both SDS-PAGE and western blotting, indicating that it was chemical and antigenic pure. By kinase assay, the recombinant PKCdelta was active. Positive inhibitor, staurosporine, was used to prove the enzyme could be greatly inhibited. Several compounds have been found to inhibit the enzyme, which indicates the preliminary application in drug lead compounds screening.
Animals ; COS Cells ; Cercopithecus aethiops ; Cloning, Molecular ; Drug Delivery Systems ; Drug Evaluation, Preclinical ; Humans ; Mice ; Protein Kinase C-delta ; antagonists & inhibitors ; biosynthesis ; genetics ; isolation & purification ; Recombinant Proteins ; antagonists & inhibitors ; biosynthesis ; genetics ; isolation & purification ; Staurosporine ; pharmacology