OBJECTIVES: To investigate the effect of interleukin (IL)-1beta on matrix metalloproteinase (MMP)-9 expression in cochlea and regulation of IL-1beta-mediated MMP-9 expression by dexamethasone and the molecular and signaling mechanisms involved. METHODS: House ear institute-organ of Corti 1 (HEI-OC1) cells were used and exposed to IL-1beta with/without dexamethasone. Glucocorticoid receptor antagonist, RU486, was used to see the role of dexamethasone. PD98059 (an extracellular signal-regulated kinases [ERKs] inhibitor), SB203580 (a p38 mitogen-activated protein kinases [MAPK] inhibitor), SP600125 (a c-Jun N-terminal kinase [JNK] inhibitor) were also used to see the role of MAPKs signaling pathway(s) in IL-1beta-induced MMP-9 expression in HEI-OC1 cells. Reverse transcription-polymerase chain reaction and gelatin zymography were used to measure mRNA expression level of MMP-9 and activity of MMP-9, respectively. RESULTS: Treatment with IL-1beta-induced the expression of MMP-9 in a dose- and time-dependent manner. IL-1beta (1 ng/mL)-induced MMP-9 expression was inhibited by dexamethasone. Interestingly, p38 MAPK inhibitor, SB203580, significantly inhibited IL-1beta-induced MMP-9 mRNA and MMP-9 activity. However, inhibition of JNKs and ERKs had no effect on the IL-1beta-induced MMP-9 expression. CONCLUSION: These results suggest that the pro-inflammatory cytokine IL-1beta strongly induces MMP-9 expression via activation of p38 MAPK signaling pathway in HEI-OC1 cells and the induction was inhibited by dexamethasone.
Cochlea ; Dexamethasone* ; Ear ; Extracellular Signal-Regulated MAP Kinases ; Gelatin ; Interleukin-1beta ; Interleukins ; JNK Mitogen-Activated Protein Kinases ; Matrix Metalloproteinase 9* ; Mifepristone ; p38 Mitogen-Activated Protein Kinases ; Receptors, Glucocorticoid ; RNA, Messenger

Ferroptosis is a newly recognized type of cell death that results from iron-dependent lipid peroxidation and is different from other types of cell death, such as apoptosis, necrosis, and autophagic cell death. This type of cell death is characterized by mitochondrial shrinkage with an increased mitochondrial membrane density and outer mitochondrial membrane rupture. Ferroptosis can be induced by a loss of activity of system Xc− and the inhibition of glutathione peroxidase 4, followed by the accumulation of lipid reactive oxygen species (ROS). In addition, inactivation of the mevalonate and transsulfuration pathways is involved in the induction of ferroptosis. Moreover, nicotinamide adenine dinucleotide phosphate oxidase and p53 promote ferroptosis by increasing ROS production, while heat shock protein beta-1 and nuclear factor erythroid 2-related factor 2 inhibit ferroptosis by reducing iron uptake. This article outlines the molecular mechanisms and signaling pathways of ferroptosis regulation, and explains the roles of ferroptosis in human disease.
Apoptosis ; Autophagy ; Cell Death* ; Glutathione Peroxidase ; HSP27 Heat-Shock Proteins ; Humans ; Iron ; Lipid Peroxidation ; Mevalonic Acid ; Mitochondrial Membranes ; NADP ; Necrosis ; Oxidoreductases ; Reactive Oxygen Species ; Rupture

Ferroptosis is a newly recognized type of cell death that results from iron-dependent lipid peroxidation and is different from other types of cell death, such as apoptosis, necrosis, and autophagic cell death. This type of cell death is characterized by mitochondrial shrinkage with an increased mitochondrial membrane density and outer mitochondrial membrane rupture. Ferroptosis can be induced by a loss of activity of system Xc− and the inhibition of glutathione peroxidase 4, followed by the accumulation of lipid reactive oxygen species (ROS). In addition, inactivation of the mevalonate and transsulfuration pathways is involved in the induction of ferroptosis. Moreover, nicotinamide adenine dinucleotide phosphate oxidase and p53 promote ferroptosis by increasing ROS production, while heat shock protein beta-1 and nuclear factor erythroid 2-related factor 2 inhibit ferroptosis by reducing iron uptake. This article outlines the molecular mechanisms and signaling pathways of ferroptosis regulation, and explains the roles of ferroptosis in human disease.
Apoptosis ; Autophagy ; Cell Death ; Glutathione Peroxidase ; HSP27 Heat-Shock Proteins ; Humans ; Iron ; Lipid Peroxidation ; Mevalonic Acid ; Mitochondrial Membranes ; NADP ; Necrosis ; Oxidoreductases ; Reactive Oxygen Species ; Rupture

Lysine-specific histone demethylase 1 (LSD1), also known as KDM1A, can remove the methyl group from lysine 4 and 9 at histone H3, which regulates transcriptional suppression and activation. Recently, high expression of LSD1 in tumors has been shown to be involved in cancer cell proliferation, metastasis, and poor prognosis. We found that SP2509, a potent and reversible inhibitor of LSD1, induced apoptosis in human renal carcinoma (Caki and ACHN) and glioma (U87MG) cells. Pharmacological inhibition and siRNA-mediated silencing of LSD1 expression effectively downregulated anti-apoptotic proteins such as Bcl-2 and Mcl-1. Ectopic expression of these proteins markedly attenuated SP2509-induced apoptosis. At a mechanistic level, we found that inhibition of LSD1 downregulated Bcl-2 at a transcriptional level. Interestingly, protein expression of Mcl-1 was modulated at a post-translation level. Our results reveal that LSD1 could induce apoptotic cell death in renal carcinoma cells through downregulation of Bcl-2 and Mcl-1.

PURPOSE: Although outcome of the children with ALL has been improved remarkably with the multidrug chemotherapy and supportive therapy, relapse is still important cause of treatment failure. One of the mechanism related to the relapse has been reported to be multidurg resistance (MDR). To investigate the relation between the expression of MDR related MDR1 gene and cell cycle and apoptosis related genes in children with ALL, this study was conducted. METHODS: The samples were collected from 9 children with ALL (5: at presentation, 4: at relapse) diagnosed at the pediatric department of Yeungnam University Hospital. From the mononuclear cells isolated from the peripheral blood or bone marrow, mRNA was extracted and analysed by RT-PCR. Using actin as a control, relative levels of mRNA of MDR1 gene, cell cycle control protein cyclin B and MAD2 and apoptosis related BAX gene were analysed. RESULTS: The expression of MDR1 gene at the presentation and the relapse were variable and showed high correlation (Pearson correlation: 0.826) with the expression of BAX gene but low correlation with the expression of cyclin B and MAD2 gene. CONCLUSION: These results suggest that mechanism involved in relapse of ALL include mechanisms other than MDR1 gene. High correlation between the expression of MDR1 gene and BAX gene suggests that high level of BAX expression increases probability of relapse but small sample size of this study precludes definite conclusion and further study is needed.
Actins ; Apoptosis ; Bone Marrow ; Cell Cycle ; Cell Cycle Checkpoints ; Child ; Cyclin B* ; Cyclins* ; Drug Therapy ; Gene Expression* ; Humans ; Precursor Cell Lymphoblastic Leukemia-Lymphoma* ; Recurrence ; RNA, Messenger ; Sample Size ; Treatment Failure

PURPOSE: The events of cell stress and cell death are linked, with the heat shock proteins (Hsps) induced in response to stress appearing to function at key regulatory points in the control of apoptosis. The purpose of this study was to investigate the effect of arisostatins A on the Hsp70 expression and signal mechanism of its transcription. MATERIALS AND METHODS: We used natural arisostatins A produced by Actinomycete, in Caki cells. We measured the growth rate of cell using trypan blue staining, and the induction of the transcriptional levels of Hsp70 with arisostatins, which was quantified by reverse transcript-polymerase chain reaction (RT-PCR) and transiently transfecting cells with a Hsp70. The induction of the transcriptional levels of Hsp70 with arisostatins A was quantified by RT-PCR and transiently transfecting cells with a Hsp70 promoter-luciferase reporter plasmid. RESULTS: Arisostatins A-induced Hsp70 up-regulation was not prevented by the overexpression of peroxiredoxinI (PrxI), PrxII or treatment of superoxide dismutase and catalase. However, the arisostatins A-mediated expression of Hsp70 was reduced significantly in Caki cells treated by the antioxidant, N-acetylcystein. Inhibition of the Janus tyrosine kinase (JAK) activity with AG490 did not inhibit the arisostatins A-induced Hsp70 up-regulation, suggesting that JAK is not associated with the arisostatins A-mediated Hsp70 expression. The mechanism of Hsp70 induction depends on the activation of heat shock factor-1. However, arisostatins A did not effect the change in the expression levels of heat shock factor-1. CONCLUSIONS: These findings suggested that Hsp directly regulates specific stress-responsive signaling pathways, which may antagonize the signaling cascades that result in apoptosis.
Apoptosis ; Carcinoma, Renal Cell* ; Catalase ; Cell Death ; Cell Line* ; Heat-Shock Proteins* ; Hot Temperature* ; HSP70 Heat-Shock Proteins* ; Plasmids ; Protein-Tyrosine Kinases ; Shock ; Superoxide Dismutase ; Trypan Blue ; Up-Regulation

Cyclooxygenase-2 (COX-2) is an important enzyme in inflammation. In this study, we investigated the underlying molecular mechanism of the synergistic effect of rottlerin on interleukin1beta (IL-1beta)-induced COX-2 expression in MDA-MB-231 human breast cancer cell line. Treatment with rottlerin enhanced IL-1beta-induced COX-2 expression at both the protein and mRNA levels. Combined treatment with rottlerin and IL-1beta significantly induced COX-2 expression, at least in part, through the enhancement of COX-2 mRNA stability. In addition, rottlerin and IL-1beta treatment drove sustained activation of p38 Mitogen-activated protein kinase (MAPK), which is involved in induced COX-2 expression. Also, a pharmacological inhibitor of p38 MAPK (SB 203580) and transient transfection with inactive p38 MAPK inhibited rottlerin and IL-1beta-induced COX-2 upregulation. However, suppression of protein kinase C delta (PKC delta) expression by siRNA or overexpression of dominant-negative PKC delta (DN-PKC-delta) did not abrogate the rottlerin plus IL-1beta-induced COX-2 expression. Furthermore, rottlerin also enhanced tumor necrosis factor-alpha (TNF-alpha), phorbol myristate acetate (PMA), and lipopolysaccharide (LPS)-induced COX-2 expression. Taken together, our results suggest that rottlerin causes IL-1beta-induced COX-2 upregulation through sustained p38 MAPK activation in MDA-MB-231 human breast cancer cells.
Acetophenones/*pharmacology ; Benzopyrans/*pharmacology ; Breast Neoplasms/drug therapy/*genetics/immunology ; Cell Line, Tumor ; Cyclooxygenase 2/*genetics ; Enzyme Activation/drug effects ; Enzyme Inhibitors/*pharmacology ; Female ; Gene Expression Regulation, Neoplastic/*drug effects ; Humans ; Interleukin-1beta/*immunology ; MAP Kinase Signaling System/drug effects ; Mallotus Plant/chemistry ; NF-kappa B/immunology ; Protein Kinase C-delta/antagonists & inhibitors ; Reactive Oxygen Species/immunology ; p38 Mitogen-Activated Protein Kinases/*immunology

BACKGROUND: Hispolon has been shown to possess antitumor effects in various cancer cells. However, the underlying mechanisms are not fully understood. In this study, we evaluated the sensitizing effect of hispolon on TNF-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis in human renal carcinoma cells. METHODS: Apoptosis was analyzed by using cell-based cytometer. The mRNA levels were assessed by reverse transcription-PCR. Bax activation was determined by oligomerization and fluorescence-activated cell sorting with Bax-NT monoclonal antibody. The protein expression was measured by Western blotting. RESULTS: Hispolon induced up-regulation of Bim and death receptors expression at the post-translational level. CONCLUSIONS: Hispolon enhanced TRAIL-mediated apoptosis in renal carcinoma cells, but not in normal cells.
Apoptosis ; Blotting, Western ; Flow Cytometry ; Humans ; Receptors, Death Domain ; RNA, Messenger ; TNF-Related Apoptosis-Inducing Ligand ; Up-Regulation

BACKGROUND: Malignant gliomas are the most common primary tumors in the central nervous system. METHODS: We investigated the combined effect of PG490 and LPS on the induction of the apoptotic pathway in human astroglioma cells. RESULTS: Treatment of U87 cells with combination of 50 nM of PG490 and 50microgram/ml of LPS resulted in increased internucleosomal DNA fragmentation, cleavage of PLC-gamma1, and down- regulation of cIAP1 and XIAP. The combination of LPS and PG490 treatment-induced apoptosis is mediated through the activation of caspase, which is inhibited by the caspase inhibitor, z-VAD-fmk. Also, release of cytochrome c was found in PG490 and LPS- cotreated U87 cell. CONCLUSION: Taken together, combination of PG490 and LPS appears to be a potent inducer of apoptosis in astrogliaoma cells, and might have some benefit in the treatment of glioma patients.
Apoptosis* ; Astrocytoma* ; Central Nervous System ; Cytochromes c ; DNA Fragmentation ; Glioma ; Humans*

HL-60 cells (human promyelocytic leukemia cells) differentiate into the monocyte/macrophage like cells that die spontaneously by apoptosis when treated with 12-O-tetradecanoylphorbol-13-acetate (TPA). It is known that inhibitors of apoptosis proteins (IAP) bind to and inhibit caspase 3, 7, 9 activity and the induction of apoptosis. In this study, we examined the expression of IAP genes during TPA induced differentiation of HL-60 cells. During the differentiation, HIAP-1, HIAP-2, and XIAP expressions were decreased in protein levels. The pan-caspase inhibitor z-VAD-fmk blocked the decrease of HIAP-1 and HIAP-2, which indicates HIAP-1 and HIAP-2 could be caspase substrates. These findings suggest that the decrease of IAP proteins is related to the induction of apoptosis that is associated with TPA- induced HL-60 cell differentiation.
Apoptosis ; Caspase 3 ; HL-60 Cells* ; Humans ; Leukemia