RESUMO
The expression of apoptosis genes in a commercial pre-designed low-density array from Applied Biosystems was evaluated in two human brain cancer cell models, LN-18 and Daoy (HTB-186™) in comparison to the reference human primary endothelial cells under basic conditions. Analysis of the gene expression in the cancer cell lines compared to the normal control revealed features reflecting anti-apoptotic and inflammatory characteristics of the former. There was an overall downregulation of apoptosis-stimulating genes in both cancer cell lines, along with an upregulation of certain apoptosis inhibitors. A number of genes demonstrated statistically significant changes in their expressions, including BAX (BCL2-associated X protein); the CARD4/NLR family, CARD domain containing 4; CASP10 (caspase 10, apoptosis-related cysteine peptidase); DAP1 (death-associated protein kinase 1), and BIRC5 (baculoviral IAP repeat-containing 5). Anti-apoptotic potential in both cell lines was demonstrated by changes in the Bax:Bcl-2 ratio and downregulation of the APAF1 gene in LN18 cells. There was also significant downregulation of extrinsic signals and the TNF/FADD/inflammatory cascade, and upregulation of caspase inhibitors (IAPs). These results provided a novel molecular characterization of important human cancer cell lines, which might provide a useful research tool for investigating the experimental model of the CNS cell.
Assuntos
Apoptose/genética , Regulação para Baixo/genética , Glioblastoma/genética , Glioblastoma/patologia , Meduloblastoma/genética , Meduloblastoma/patologia , Regulação para Cima/genética , Proteínas Reguladoras de Apoptose/genética , Fator Apoptótico 1 Ativador de Proteases/genética , Caspase 10/genética , Linhagem Celular Tumoral , Proteína de Domínio de Morte Associada a Fas/genética , Humanos , Proteínas Inibidoras de Apoptose/genética , Proteína Adaptadora de Sinalização NOD1/genética , Survivina , Fator de Necrose Tumoral alfa/genética , Proteína X Associada a bcl-2/genéticaRESUMO
Humanin (HN) is a newly discovered 24-amino acid peptide, which may suppress neuronal cell death. HN cDNA includes the open reading frame (HN-ORF) of 75 bases, located 950 bases downstream of the 5' end of the HN cDNA. It was demonstrated that HN cDNA is 99% identical with mitochondrial DNA (mtDNA) sequence. HN homologues have been identified as expressed sequence tags (ESTs) in rat and nematode. Certain regions homologous to the HN cDNA exist on human chromosomes. HN forms homodimers and multimers and this seems to be essential for the peptide functions. HN acts as a ligand for formyl peptide receptor-like 1 (FPRL1) and 2 (FPRL2). It was demonstrated that HN plays a protective role by an antiapoptotic activity interfering with Bax activation, and suppressing Bax-dependent apoptosis. HN is also shown to suppress the c-Jun N-terminal kinase (JNK) and ASK/JNK-mediated neuronal cell death. Several studies also confirm that HN could be important in prevention of angiopathy-associated Alzheimer's disease dementia, diseases related to mitochondrial dysfunction (MELAS), and other types of beta-amyloid accumulation associated neurodegeneration. A very recent study demonstrated a pluripotent cytoprotective effect and mechanisms of HNs in cells other than from the CNS, such as germ cells, or panreatic b-cells, and potent physiological consequences that result from HN interaction with IGFBP3 and STAT3. The in vivo studies suggest that humanin may protect against cognitive impairment, also due to ischemia/reperfusion injury.
Assuntos
Apoptose/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fármacos Neuroprotetores/metabolismo , Animais , Sequência de Bases , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/prevenção & controle , Citoproteção/fisiologia , DNA Complementar , DNA Mitocondrial/química , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/genética , Traumatismo por Reperfusão/fisiopatologia , Traumatismo por Reperfusão/prevenção & controle , Homologia de SequênciaRESUMO
MicroRNAs (miRNAs) are a family of small, noncoding RNAs that repress gene expression at the post-transcriptional level. Over 700 miRNAs have been identified in the human genome, of which 20% to 30% regulate human protein-coding genes. Functional in vitro studies have shown that miRNAs are critical for endothelial cell gene expression and function. miRNAs were found in atherosclerosis, cardiac hypertrophy, arterial hypertension, coronary artery disease, diabetes, and inflammatory diseases. We review the current knowledge about the role of miRNAs in endothelial cells with emphasis on the regulation of cellular senescence, angiogenesis, and vascular inflammation. It has been shown that miR-34a, miR-217, miR-200, miR-146c, and miR-181a are responsible for the regulation of cell stress and proliferation processes. Proangiogenic factors include miR-130a, miR-210, miR-424, miR-17-92, miR-27-b, let-7f, and miR-217, while miR-221 and miR-222 have antiangiogenic properties. Other known miRNAs, including miR-31, miR17-3p, miR-155, miR-221, miR-222, and miR-126, are important factors in the regulation of vascular inflammation. Studies show that miRNA expression analysis can be used in the diagnosis and treatment of various diseases; however, additional research is needed before it is used in routine clinical setting.
Assuntos
Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Endotélio Vascular/metabolismo , Inflamação/genética , Inflamação/metabolismo , MicroRNAs/metabolismo , Animais , Aterosclerose/genética , Aterosclerose/metabolismo , Cardiomegalia/metabolismo , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/metabolismo , Humanos , Hipertensão/genética , Hipertensão/metabolismoRESUMO
Humanin (HN) is a newly discovered 24-amino acid peptide, which may suppress neuronal cell death. HN cDNA includes an open reading frame (HN-ORF) of 75 bases located 950 bases downstream of the 5' end of the HN cDNA. It has been demonstrated that HN cDNA is 99% identical to the mitochondrial DNA (mtDNA) sequence. HN homologs have been identified as expressed sequence tags (ESTs) in both rats and nematodes. Certain regions that are homologous to the HN cDNA exist on human chromosomes. HN forms homodimers and multimers and this action seems to be essential for peptide function. HN acts as a ligand for formyl peptide receptor-like 1 (FPRL1) and 2 (FPRL2). It has been demonstrated that HN plays a protective role through its antiapoptotic activity that interferes with Bax activation, which suppresses Bax-dependent apoptosis. HN has also been shown to suppress the c-Jun N-terminal kinase (JNK) and ASK/JNK-mediated neuronal cell death. Several studies have also confirmed that HN could be important in the prevention of angiopathy-associated Alzheimer's disease dementia, diseases related to mitochondrial dysfunction (MELAS), and other types of ß-amyloid accumulation-associated neurodegeneration. Avery recent study demonstrated a pluripotent cytoprotective effect and mechanisms of HNs in cells not from the CNS, such as germ cells or pancreatic ß-cells, and the potent physiological consequences that result from HN interaction with IGFBP3 and STAT3. In vivo studies suggest that HN may also protect against cognitive impairment due to ischemia/reperfusion injury.
