scholarly journals MCG10, a Novel p53 Target Gene That Encodes a KH Domain RNA-Binding Protein, Is Capable of Inducing Apoptosis and Cell Cycle Arrest in G2-M

2000 ◽  
Vol 20 (15) ◽  
pp. 5602-5618 ◽  
Author(s):  
Jianhui Zhu ◽  
Xinbin Chen
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Cell Cycle Arrest ◽  
Target Gene ◽  
Rna Binding ◽  
Rna Binding Protein ◽  
Wild Type ◽  
Cycle Arrest ◽  
Kh Domain ◽  
P53 Target Gene

ABSTRACT p53, a tumor suppressor, inhibits cell proliferation by inducing cellular genes involved in the regulation of the cell cycle.MCG10, a novel cellular p53 target gene, was identified in a cDNA subtraction assay with mRNA isolated from a p53-producing cell line. MCG10 can be induced by wild-type but not mutant p53 and by DNA damage via two potential p53-responsive elements in the promoter of the MCG10 gene. The MCG10 gene contains 10 exons and is located at chromosome 3p21, a region highly susceptible to aberrant chromosomal rearrangements and deletions in human neoplasia. The MCG10 gene locus encodes at least two alternatively spliced transcripts, MCG10 and MCG10as. The MCG10 and MCG10as proteins contain two domains homologous to the heterogeneous nuclear ribonucleoprotein K homology (KH) domain. By generating cell lines that inducibly express either wild-type or mutated forms of MCG10 and MCG10as, we found that MCG10 and MCG10as can suppress cell proliferation by inducing apoptosis and cell cycle arrest in G2-M. In addition, we found that MCG10 and MCG10as, through their KH domains, can bind poly(C) and that their RNA-binding activity is necessary for inducing apoptosis and cell cycle arrest. Furthermore, we found that the level of the poly(C) binding MCG10 protein is increased in cells treated with the DNA-damaging agent camptothecin in a p53-dependent manner. These results suggest that the MCG10 RNA-binding protein is a potential mediator of p53 tumor suppression.

scholarly journals The RNA-binding protein SART3 promotes miR-34a biogenesis and G1 cell cycle arrest in lung cancer cells

2019 ◽  
Vol 294 (46) ◽  
pp. 17188-17196 ◽  
Author(s):  
Emily J. Sherman ◽  
Dylan C. Mitchell ◽  
Amanda L. Garner
Keyword(s):  
Lung Cancer ◽  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Rna Binding ◽  
Rna Binding Proteins ◽  
Binding Protein ◽  
Rna Binding Protein ◽  
Mirna Biogenesis ◽  
Regulatory Pathways ◽  
Cycle Arrest

MicroRNAs (miRNAs or miRs) are small, noncoding RNAs that are implicated in the regulation of most biological processes. Global miRNA biogenesis is altered in many cancers, and RNA-binding proteins play a role in miRNA biogenesis, presenting a promising avenue for targeting miRNA dysregulation in diseases. miR-34a exhibits tumor-suppressive activities by targeting cell cycle regulators CDK4/6 and anti-apoptotic factor BCL-2, among other regulatory pathways such as Wnt, TGF-β, and Notch signaling. Many cancers exhibit down-regulation or loss of miR-34a, and synthetic miR-34a supplementation has been shown to inhibit tumor growth in vivo. However, the post-transcriptional mechanisms that cause miR-34a loss in cancer are not entirely understood. Here, using a proteomics-mediated approach in non-small-cell lung cancer (NSCLC) cells, we identified squamous cell carcinoma antigen recognized by T-cells 3 (SART3) as a putative pre-miR-34a–binding protein. SART3 is a spliceosome recycling factor and nuclear RNA-binding protein with no previously reported role in miRNA regulation. We found that SART3 binds pre-miR-34a with higher specificity than pre-let-7d (used as a negative control) and elucidated a new functional role for SART3 in NSCLC cells. SART3 overexpression increased miR-34a levels, down-regulated the miR-34a target genes CDK4/6, and caused a cell cycle arrest in the G1 phase. In vitro binding experiments revealed that the RNA-recognition motifs within the SART3 sequence are responsible for selective pre-miR-34a binding. Our results provide evidence for a significant role of SART3 in miR-34a biogenesis and cell cycle progression in NSCLC cells.

scholarly journals Genetic Studies with the Fission YeastSchizosaccharomyces pombe Suggest Involvement of Wee1, Ppa2, and Rad24 in Induction of Cell Cycle Arrest by Human Immunodeficiency Virus Type 1 Vpr

2000 ◽  
Vol 74 (6) ◽  
pp. 2636-2646 ◽  
Author(s):  
Michiaki Masuda ◽  
Yukiko Nagai ◽  
Norihito Oshima ◽  
Koichi Tanaka ◽  
Hiroshi Murakami ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Human Immunodeficiency Virus ◽  
Cell Proliferation ◽  
Cell Cycle Arrest ◽  
Wild Type ◽  
Genetic Studies ◽  
Cycle Arrest ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT Accessory protein Vpr of human immunodeficiency virus type 1 (HIV-1) arrests cell cycling at G2/M phase in human and simian cells. Recently, it has been shown that Vpr also causes cell cycle arrest in the fission yeast Schizosaccharomyces pombe, which shares the cell cycle regulatory mechanisms with higher eukaryotes including humans. In this study, in order to identify host cellular factors involved in Vpr-induced cell cycle arrest, the ability of Vpr to cause elongated cellular morphology (cdcphenotype) typical of G2/M cell cycle arrest in wild-type and various mutant strains of S. pombe was examined. Our results indicated that Vpr caused the cdc phenotype in wild-type S. pombe as well as in strains carrying mutations, such as the cdc2-3w, Δcdc25,rad1-1, Δchk1, Δmik1, and Δppa1 strains. However, other mutants, such as thecdc2-1w, Δwee1, Δppa2, and Δrad24 strains, failed to show a distinct cdcphenotype in response to Vpr expression. Results of these genetic studies suggested that Wee1, Ppa2, and Rad24 might be required for induction of cell cycle arrest by HIV-1 Vpr. Cell proliferation was inhibited by Vpr expression in all of the strains examined including the ones that did not show the cdc phenotype. The results supported the previously suggested possibility that Vpr affects the cell cycle and cell proliferation through different pathways.

scholarly journals PTENInhibits Cell Proliferation, Promotes Cell Apoptosis, and Induces Cell Cycle Arrest via Downregulating the PI3K/AKT/hTERTPathway in Lung Adenocarcinoma A549 Cells

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Xiao-Xiao Lu ◽  
Lan-Yu Cao ◽  
Xi Chen ◽  
Jian Xiao ◽  
Yong Zou ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Lung Adenocarcinoma ◽  
Cell Cycle Arrest ◽  
Cell Apoptosis ◽  
A549 Cells ◽  
Akt Pathway ◽  
Wild Type ◽  
Cycle Arrest ◽  
Lung Adenocarcinoma A549

PTENplays an essential role in tumorigenesis and both its mutation and inactivation can influence proliferation, apoptosis, and cell cycle progression in tumor cells. However, the precise role ofPTENin lung cancer cells has not been well studied. To address this, we have generated lung adenocarcinoma A549 cells overexpressing wild-type or mutantPTENas well as A549 cells expressing a siRNA directed toward endogenousPTEN. Overexpression of wild-typePTENprofoundly inhibited cell proliferation, promoted cell apoptosis, caused cell cycle arrest at G1, downregulated p-AKT, and decreased expression of the telomerase proteinhTERT. In contrast, in cells expressing aPTENdirected siRNA, the opposite effects on cell proliferation, apoptosis, cell cycle arrest, p-AKT levels, andhTERTprotein expression were observed. A549 cells transfected with aPTENmutant lacking phosphatase activity (PTEN-C124A) or an empty vector (null) did not show any effect. Furthermore, using the PI3K/AKT pathway blocker LY294002, we confirmed that the PI3K/AKT pathway was involved in mediating these effects ofPTEN. Taken together, we have demonstrated thatPTENdownregulates the PI3K/AKT/hTERTpathway, thereby suppressing the growth of lung adenocarcinoma cells. Our study may provide evidence for a promising therapeutic target for the treatment of lung adenocarcinoma.

scholarly journals Induction of apoptosis and cell cycle arrest by chloroform fraction of Juniperus phoenicea and chemical constituents analysis

2021 ◽  
Vol 19 (1) ◽  
pp. 119-127
Author(s):  
Ibrahim O. Barnawi ◽  
Fahd A. Nasr ◽  
Omar M. Noman ◽  
Ali S. Alqahtani ◽  
Mohammed Al-zharani ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Cell Cycle Arrest ◽  
Cancer Cells ◽  
Chloroform Fraction ◽  
Active Fraction ◽  
Cycle Arrest ◽  
Juniperus Phoenicea ◽  
Medicinal Properties ◽  
Mcf 7

Abstract Different phytochemicals from various plant species exhibit promising medicinal properties against cancer. Juniperus phoenicea is a plant species that has been found to present medicinal properties. Herein, crude extract and fractions of J. phoenicea were examined to determine its anticancer properties against several cancer cells. The active fraction was chosen to assess its activity on cell cycle progression and apoptosis induction by annexin and propidium iodide (PI) biomarkers. Further, phytochemical screening for possible contents of active fraction using gas chromatography–mass spectrometry (GC-MS) analysis was conducted. It was demonstrated that cell proliferation was suppressed, and the MCF-7 cell line was the most sensitive to J. phoenicea chloroform fraction (JPCF), with the IC50 values of 24.5 μg/mL. The anti-proliferation activity of JPCF in MCF-7 cells was linked to the aggregation of cells in the G1 phase, increases in early and late apoptosis as well as necrotic cell death. Contents analysis of JPCF using GC-MS analysis identified 3-methyl-5-(2′,6′,6′-trimethylcyclohex-1′-enyl)-1-penten-3-ol (16.5%), methyl 8-oxooctanoate (15.61%), cubenol (13.48%), and 7-oxabicyclo [2.2.1] heptane (12.14%) as major constituents. Our present study provides clear evidence that J. phoenicea can inhibit cell proliferation, trigger cell cycle arrest, and induce apoptosis in tested cancer cells.

scholarly journals Hyperbaric oxygen promotes not only glioblastoma proliferation but also chemosensitization by inhibiting HIF1α/HIF2α-Sox2

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Pan Wang ◽  
Sheng Gong ◽  
Jinyu Pan ◽  
Junwei Wang ◽  
Dewei Zou ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Cell Cycle Arrest ◽  
Hyperbaric Oxygen ◽  
Cell Cycle Progression ◽  
Malignant Progression ◽  
Cycle Progression ◽  
Chemotherapy Sensitivity ◽  
Hypoxic Conditions ◽  
Cycle Arrest

AbstractThere exists a consensus that combining hyperbaric oxygen (HBO) and chemotherapy promotes chemotherapy sensitivity in GBM cells. However, few studies have explored the mechanism involved. HIF1α and HIF2α are the two main molecules that contribute to GBM malignant progression by inhibiting apoptosis or maintaining stemness under hypoxic conditions. Moreover, Sox2, a marker of stemness, also contributes to GBM malignant progression through stemness maintenance or cell cycle arrest. Briefly, HIF1α, HIF2α and Sox2 are highly expressed under hypoxia and contribute to GBM growth and chemoresistance. However, after exposure to HBO for GBM, whether the expression of the above factors is decreased, resulting in chemosensitization, remains unknown. Therefore, we performed a series of studies and determined that the expression of HIF1α, HIF2α and Sox2 was decreased after HBO and that HBO promoted GBM cell proliferation through cell cycle progression, albeit with a decrease in stemness, thus contributing to chemosensitization via the inhibition of HIF1α/HIF2α-Sox2.

Down-Regulation of Asparagine Synthetase Induces Cell Cycle Arrest and Inhibits Cell Proliferation of Breast Cancer

2014 ◽  
Vol 84 (5) ◽  
pp. 578-584 ◽  
Author(s):  
Hongjian Yang ◽  
Xiangming He ◽  
Yabing Zheng ◽  
Weiliang Feng ◽  
Xianghou Xia ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Cycle ◽  
Cell Proliferation ◽  
Cell Cycle Arrest ◽  
Asparagine Synthetase ◽  
Down Regulation ◽  
Cycle Arrest
Sign in / Sign up

Export Citation Format

Share Document