BACKGROUNDBrain hypoplasia and mental retardation in Down syndrome (DS) can be attributed to a severe and selective disruption of neurogenesis. Secondary disruption of the transcriptome, as well as primary gene dosage imbalance, is responsible for the phenotype. MicroRNA (miRNA) expression is relatively abundant in brain tissue. Perturbed miRNA expression might contribute to the cellular events underlying the pathology in DS.

METHODSMiRNA expression profiles in the cerebrum of Ts65Dn mice, a DS model, were examined with a real-time RT-PCR array. MiRNA target gene expression was detected by real-time quantitative PCR and Western blotting. Based on the prediction of their cerebrum-specific targets, the functions of the misregulated miRNAs were annotated by Gene Ontology (GO) enrichment analysis.

RESULTSA total of 342 miRNAs were examined. Among them, 20 miRNAs showed decreased expression in the brains of Ts65Dn mice, and some of these belonged to the same family. Two known targets of the miR-200 family, Lfng and Zeb2, were specifically selected to compare their expression in the cerebrum of Ts65Dn mice with those of euploids. However, no significant difference was found in terms of mRNA and protein expression levels of these genes. By enrichment analysis of the cerebrum-specific targets of each miRNA, we found that 15 of the differential miRNAs could significantly affect target genes that were enriched in the GO biological processes related to nervous system development.

CONCLUSIONPerturbed expression of multiple functionally cooperative miRNAs contributes to the cellular events underlying the pathogenesis of DS.

Animals ; Brain ; metabolism ; Disease Models, Animal ; Down Syndrome ; etiology ; genetics ; Gene Expression Regulation ; Mice ; MicroRNAs ; physiology

CKLF-like MARVEL transmembrane domain containing member/chemokine-like factor super family member (CKLFSF/CMTM) is a novel tumor suppressor gene. CMTM3 is broadly expressed in normal human tissues and evolutionary conserved,especially in testis,spleen,and some cells of peripheral blood mononuclear cells. However,its expression is undetectable or down-regulated in most carcinoma cell lines and tissues. Restoration of CMTM3 may inhibit the proliferation,migration,and invasion of carcinoma cells. Although the exact mechanism of its anti-tumor activity remains unclear,CKLFSF3/CMTM3 is closely connected with immune system and associated with sex during tumorigenesis. The study advances of CKLFSF3/CMTM3 are elaborated in this review as CMTM3 may be a new target in the gene therapies for tumors,especially genitourinary tumors,while further studies on CMTM3 and its anti-tumor mechanisms are warranted.
Cell Transformation, Neoplastic ; Chemokines ; genetics ; physiology ; Down-Regulation ; Humans ; Leukocytes, Mononuclear ; MARVEL Domain-Containing Proteins ; genetics ; physiology ; Male ; Neoplasms ; pathology

OBJECTIVE: To investigate the expression of miR-33b in hepatocellular carcinoma (HCC) and to explore regulatory mechanism of miR-33b for cell proliferation of HCC.
 METHODS: HCC tissues and adjacent non-tumor tissues were collected for this study (n=32 for each). Real-time PCR and Western blot were conducted to examine the mRNA and protein expression, respectively. MTT assay was used to detect the cell proliferation. Luciferase reporter gene assay was performed to verify the target relationship between miR-33b and Sal-like 4 (SALL4).
 RESULTS: MiR-33b was significantly downregulated in HCC tissues compared with adjacent non-tumor tissues. Overexpression of miR-33b decreased the proliferation of HCC LH86 cells. SALL4 was identified as a target gene of miR-33b, and its protein expression was negatively regulated by miR-33b. Overexpression of SALL4 reversed the suppressive effect of miR-33b on LH86 cell proliferation. SALL4 was significantly upregulated in HCC tissues compared with adjacent non-tumor tissues.
 CONCLUSION The miR-33b suppresses HCC cell proliferation through down-regulation of SALL4.
Carcinoma, Hepatocellular ; chemistry ; genetics ; physiopathology ; Cell Proliferation ; genetics ; physiology ; Down-Regulation ; Gene Expression Regulation, Neoplastic ; genetics ; physiology ; Humans ; Liver Neoplasms ; MicroRNAs ; analysis ; genetics ; physiology ; RNA, Messenger ; Real-Time Polymerase Chain Reaction ; Transcription Factors ; genetics ; physiology ; Tumor Cells, Cultured ; Up-Regulation

Animals ; Apoptosis ; Cell Line, Tumor ; Down-Regulation ; Melanoma, Experimental ; pathology ; virology ; Mice ; Receptor, IGF Type 1 ; physiology ; Sendai virus ; pathogenicity

The effects of microRNA-34a (miR-34a)-regulated Notch1 gene on the proliferation and apoptosis of the human glioma cell line U87 were investigated in this study. The U87 cells were divided into miR-34a mimics, negative control, mock transfection and blank control groups in terms of different treatments. In miR-34a mimics group, human U87 glioma cells were transfected with miR-34a mimics by using lipofectamine 2000. The cells transfected with nonsense microRNA were set up as negative control group. Those treated with lipofectamine 2000 only were designated to the mock tranfection group. In the blank control group, the cells were cultured routinely and no treatment was given. The expression of miR-34a and Notch1 was detected by using real-time RT-PCR. Western blotting was employed to monitor the change in Notch1 protein. Cell proliferation and apoptosis were measured by CCK-8 and flow cytometry. The results showed that the proliferative ability of U87 cells was significantly reduced and the apoptotic cells increased in miR-34a mimics group relative to control groups. The expression of miR-34a was significantly up-regulated in mimics group as compared with control groups (P<0.05). Furthermore, Notch1 protein levels were significantly decreased in miR-34a mimics group when compared with control groups (P<0.05), but the mRNA expression of Notch1 showed no significant difference among these groups. It was concluded that miR-34a may suppress the proliferation and induce apoptosis of U87 cells by decreasing the expression of target gene Notch1, suggesting that miR-34a may become a promising gene therapeutic target for brain glioma.
Cell Line, Tumor ; Cell Proliferation ; Down-Regulation ; genetics ; Glioma ; pathology ; physiopathology ; Humans ; MicroRNAs ; genetics ; Receptor, Notch1 ; physiology ; Transfection

PURPOSE: Hyperoxia has the chief biological effect of cell death. We have previously reported that cathepsin B (CB) is related to fetal alveolar type II cell (FATIIC) death and pretreatment of recombinant IL-10 (rIL-10) attenuates type II cell death during 65%-hyperoixa. In this study, we investigated what kinds of changes of CB expression are induced in FATIICs at different concentrations of hyperoxia (65%- and 85%-hyperoxia) and whether pretreatment with rIL-10 reduces the expression of CB in FATIICs during hyperoxia. MATERIALS AND METHODS: Isolated embryonic day 19 fetal rat alveolar type II cells were cultured and exposed to 65%- and 85%-hyperoxia for 12 h and 24 h. Cells in room air were used as controls. Cytotoxicity was assessed by lactate dehydrogenase (LDH) released into the supernatant. Expression of CB was analyzed by fluorescence-based assay upon cell lysis and western blotting, and LDH-release was re-analyzed after preincubation of cathepsin B-inhibitor (CBI). IL-10 production was analyzed by ELISA, and LDH-release was re-assessed after preincubation with rIL-10 and CB expression was re-analyzed by western blotting and real-time PCR. RESULTS: LDH-release and CB expression in FATIICs were enhanced significantly in an oxygen-concentration-dependent manner during hyperoxia, whereas caspase-3 was not activated. Preincubation of FATIICs with CBI significantly reduced LDH-release during hyperoxia. IL-10-release decreased in an oxygen-concentration-dependent fashion, and preincubation of the cells with rIL-10 significantly reduced cellular necrosis and expression of CB in FATIICs which were exposed to 65%- and 85%-hyperoxia. CONCLUSION: Our study suggests that CB is enhanced in an oxygen-concentration-dependent manner, and IL-10 has an inhibitory effect on CB expression in FATIICs during hyperoxia.
Animals ; Cathepsin B/*genetics/metabolism ; *Down-Regulation ; Gene Expression Regulation ; Hyperoxia/*genetics ; Interleukin-10/*pharmacology/physiology ; L-Lactate Dehydrogenase/metabolism ; Necrosis/chemically induced ; Oxygen/metabolism ; Rats

OBJECTIVETo screen the genes related with leukocyte responses in mice early after burn injury by bioinformatic analysis of the gene expression profiling data.

METHODSGene expression profiles were obtained from GEO (GSE7404, Mouse musculus, 25% TBSA, full-thickness) database. After screening of the differentially expressed genes (DEGs) through paired-sample t-test and fold-change, DAVID online tools were used to select the DEGs related to leukocyte responses to burns by GO functional enrichment analysis; the interacting genes identified through KEGG pathway enrichment analysis were transferred to STRING to construct the protein-protein interaction (PPI) network. Biological annotation of the sub-networks was executed using the software Cytoscape. Real-time PCR was used to verify the DEGs identified in mice.

RESULTSOf the 259 leukocyte response-related DEGs screened at 1 day post-burn, 118 were up-regulated and 141 were down-regulated. KEGG pathway enrichment analysis showed that the pathways were associated with the immune function, cell growth and cell death. PPI network and module analysis suggested that some of genes (such as Lck, Stat1, Myd88, Stat3, and Jun) play critical roles in the PPI network post-burn. RT-PCR results were consistent with those of bioinformatic analysis.

CONCLUSIONSLck, Stat1, Myd88, Stat3, and Jun might be critical players in the development of leukocyte response in mice early after burn injury. Our finding provides new insights into the pathogenesis of leukocyte response to burn injury and identifies several potential biomarkers for burn treatment.

Animals ; Burns ; genetics ; Computational Biology ; Down-Regulation ; Gene Expression Profiling ; Gene Regulatory Networks ; Leukocytes ; physiology ; Mice ; Real-Time Polymerase Chain Reaction ; Software ; Up-Regulation

OBJECTIVETo investigate the expression and function of miR-218 in gastric cancer.

METHODSmiR-218 levels were evaluated in 20 non-cardia gastric cancer tissues using TaqMan stem-loop real-time PCR analysis. Pre-miR-218 and anti-miR-218 inhibitor were used to change the miR-218 expression level and examine its effects on cell proliferation, apoptosis, cell cycle and cell invasion.

RESULTSComparing with the corresponding normal tissues, miR-218 expression was significantly reduced in the gastric cancer tissue (P < 0.01). Forced expression of miR-218 increased apoptosis in AGS cells. The proportion of apoptosis cells induced by transfection of pre-miR-218 was greater than that induced by control (21.6% vs. 10.4%, P = 0.032). Pre-miR-218 resulted in a significantly decreased cell growth activity (P < 0.01) and cell invasion (P < 0.05) of AGS cells compared with that of the control.

CONCLUSIONmiR-218 expression is reduced in gastric cancer. miR-218 may function as a tumor suppressor in gastric carcinoma.

Apoptosis ; Cell Cycle ; Cell Line, Tumor ; Cell Proliferation ; Down-Regulation ; Gene Expression Regulation, Neoplastic ; Humans ; MicroRNAs ; genetics ; metabolism ; physiology ; Neoplasm Invasiveness ; Stomach Neoplasms ; genetics ; metabolism ; pathology ; Transfection

The tetrapeptide N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP), a physiological regulator of cell proliferation, has been principally reported as a potent inhibitor of the proliferation of haematopoietic stem cells and progenitors. The purpose of this study was to investigate whether the AcSDKP may directly affect the proliferative potential of human bone marrow mesenchymal stem cells (MSCs) in vitro. We added AcSDKP to the cultures of human bone marrow mononuclear cells and measured the number and average area of MSC colonies. MTT colorimetric assay and mitotic index determination were further used to examine the proliferative state of the third passage MSCs in subcultures with or without the addition of AcSDKP. In addition, we evaluated whether AcSDKP may kill MSCs by the trypan blue dye exclusion test. The results showed that the colony forming capacity, the number of viable cells and the mitotic index were reduced in human bone marrow MSCs cultured in 1x10(-12) mol/L to 1x10(-9) mol/L AcSDKP. Maximum inhibitory activity appeared in 1x10(-11) mol/L of AcSDKP. No difference in percent of living cells was observed between the MSC subcultures with and without the addition of AcSDKP. As a result, AcSDKP within a certain range of concentrations has negatively regulatory effects on the proliferation of human bone marrow MSCs in vitro.
Bone Marrow Cells ; cytology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Down-Regulation ; physiology ; Growth Inhibitors ; physiology ; Humans ; Mesenchymal Stromal Cells ; cytology ; Oligopeptides ; physiology

Antioxidants ; metabolism ; pharmacology ; Down-Regulation ; Gene Expression Regulation ; Humans ; NF-E2-Related Factor 2 ; genetics ; metabolism ; physiology ; Neoplasms ; genetics ; metabolism ; Oxidative Stress ; genetics ; physiology ; Response Elements ; physiology ; Signal Transduction ; physiology