The Polo kinase Cdc5 is regulated at multiple levels in the adaptation response to telomere dysfunction

Telomere dysfunction activates the DNA damage checkpoint to induce a cell cycle arrest. After an extended period of time, however, cells can bypass the arrest and undergo cell division despite the persistence of the initial damage, a process called adaptation to DNA damage. The Polo kinase Cdc5 in Saccharomyces cerevisiae is essential for adaptation and for many other cell-cycle processes. How the regulation of Cdc5 in response to telomere dysfunction relates to adaptation is not clear. Here, we report that Cdc5 protein level decreases after telomere dysfunction in a Mec1-, Rad53- and Ndd1-dependent manner. This regulation of Cdc5 is important to maintain long-term cell cycle arrest but not for the initial checkpoint arrest. We find that both Cdc5 and the adaptation-deficient mutant protein Cdc5-ad are heavily phosphorylated and several phosphorylation sites modulate adaptation efficiency. The PP2A phosphatases are involved in Cdc5-ad phosphorylation status and contribute to adaptation mechanisms. We finally propose that Cdc5 orchestrates multiple cell cycle pathways to promote adaptation.

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Cucurbitacin B Induced ATM-Mediated DNA Damage Causes G2/M Cell Cycle Arrest in a ROS-Dependent Manner

PLoS ONE ◽

10.1371/journal.pone.0088140 ◽

2014 ◽

Vol 9 (2) ◽

pp. e88140 ◽

Cited By ~ 42

Author(s):

Jiajie Guo ◽

Guosheng Wu ◽

Jiaolin Bao ◽

Wenhui Hao ◽

Jinjian Lu ◽

...

Keyword(s):

Cell Cycle ◽

Dna Damage ◽

Cell Cycle Arrest ◽

Dependent Manner ◽

M Cell ◽

Cucurbitacin B ◽

Cycle Arrest

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By Blocking Apoptosis, Bcl-2 in p38-Dependent Manner Promotes Cell Cycle Arrest and Accelerated Senescence After DNA Damage and Serum Withdrawal

Cell Cycle ◽

10.4161/cc.6.17.4610 ◽

2007 ◽

Vol 6 (17) ◽

pp. 2171-2177 ◽

Cited By ~ 24

Author(s):

Anna Nelyudova ◽

Nikolai D. Aksenov ◽

Valery Pospelov ◽

Tatiana Pospelova

Keyword(s):

Cell Cycle ◽

Dna Damage ◽

Cell Cycle Arrest ◽

Dependent Manner ◽

Serum Withdrawal ◽

Cycle Arrest ◽

Accelerated Senescence

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DN-p73 is activated after DNA damage in a p53-dependent manner to regulate p53-induced cell cycle arrest

Oncogene ◽

10.1038/sj.onc.1205465 ◽

2002 ◽

Vol 21 (23) ◽

pp. 3796-3803 ◽

Cited By ~ 52

Author(s):

Stefania Vossio ◽

Emanuele Palescandolo ◽

Natalia Pediconi ◽

Francesca Moretti ◽

Clara Balsano ◽

...

Keyword(s):

Cell Cycle ◽

Dna Damage ◽

Cell Cycle Arrest ◽

Dependent Manner ◽

Cycle Arrest

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Vernonia calvoana Shows Promise towards the Treatment of Ovarian Cancer

International Journal of Molecular Sciences ◽

10.3390/ijms21124429 ◽

2020 ◽

Vol 21 (12) ◽

pp. 4429

Author(s):

Ariane T. Mbemi ◽

Jennifer N. Sims ◽

Clement G. Yedjou ◽

Felicite K. Noubissi ◽

Christian R. Gomez ◽

...

Keyword(s):

Oxidative Stress ◽

Cell Cycle ◽

Ovarian Cancer ◽

Dna Damage ◽

Antitumor Activity ◽

Cell Cycle Arrest ◽

Cancer Cells ◽

Ovarian Cancer Cells ◽

Dependent Manner ◽

Cycle Arrest

The treatment for ovarian cancers includes chemotherapies which use drugs such as cisplatin, paclitaxel, carboplatin, platinum, taxanes, or their combination, and other molecular target therapies. However, these current therapies are often accompanied with side effects. Vernonia calvoana (VC) is a valuable edible medicinal plant that is widespread in West Africa. In vitro data in our lab demonstrated that VC crude extract inhibits human ovarian cancer cells in a dose-dependent manner, suggesting its antitumor activity. From the VC crude extract, we have generated 10 fractions and VC fraction 7 (F7) appears to show the highest antitumor activity towards ovarian cancer cells. However, the mechanisms by which VC F7 exerts its antitumor activity in cancer cells remain largely unknown. We hypothesized that VC F7 inhibits cell proliferation and induces DNA damage and cell cycle arrest in ovarian cells through oxidative stress. To test our hypothesis, we extracted and fractionated VC leaves. The effects of VC F7 were tested in OVCAR-3 cells. Viability was assessed by the means of MTS assay. Cell morphology was analyzed by acridine orange and propidium iodide (AO/PI) dye using a fluorescent microscope. Oxidative stress biomarkers were evaluated by the means of lipid peroxidation, catalase, and glutathione peroxidase assays, respectively. The degree of DNA damage was assessed by comet assay. Cell cycle distribution was assessed by flow cytometry. Data generated from the MTS assay demonstrated that VC F7 inhibits the growth of OVCAR-3 cells in a dose-dependent manner, showing a gradual increase in the loss of viability in VC F7-treated cells. Data obtained from the AO/PI dye assessment revealed morphological alterations and exhibited characteristics such as loss of cellular membrane integrity, cell shrinkage, cell membrane damage, organelle breakdown, and detachment from the culture plate. We observed a significant increase (p < 0.05) in the levels of malondialdhyde (MDA) production in treated cells compared to the control. A gradual decrease in both catalase and glutathione peroxidase activities were observed in the treated cells compared to the control. Data obtained from the comet assay showed a significant increase (p < 0.05) in the percentages of DNA cleavage and comet tail length. The results of the flow cytometry analysis indicated VC F7 treatment caused cell cycle arrest at the S-phase checkpoint. Taken together, our results demonstrate that VC F7 exerts its anticancer activity by inhibiting cell proliferation, inducing DNA damage, and causing cell cycle arrest through oxidative stress in OVAR-3 cells. This finding suggests that VC F7 may be a potential alternative dietary agent for the prevention and/or treatment of ovarian cancer.

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Cytolethal Distending Toxin from Aggregatibacter actinomycetemcomitans Induces DNA Damage, S/G2 Cell Cycle Arrest, and Caspase- Independent Death in a Saccharomyces cerevisiae Model

Infection and Immunity ◽

10.1128/iai.00857-09 ◽

2009 ◽

Vol 78 (2) ◽

pp. 783-792 ◽

Cited By ~ 21

Author(s):

Oranart Matangkasombut ◽

Roongtiwa Wattanawaraporn ◽

Keiko Tsuruda ◽

Masaru Ohara ◽

Motoyuki Sugai ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Cell Cycle ◽

Dna Damage ◽

Cell Death ◽

Cell Cycle Arrest ◽

Aggregatibacter Actinomycetemcomitans ◽

Cytolethal Distending Toxin ◽

Dependent Manner ◽

Cycle Arrest ◽

Yeast Strains

ABSTRACT Cytolethal distending toxin (CDT) is a bacterial toxin that induces G2/M cell cycle arrest, cell distension, and/or apoptosis in mammalian cells. It is produced by several Gram-negative species and may contribute to their pathogenicity. The catalytic subunit CdtB has homology with DNase I and may act as a genotoxin. However, the mechanism by which CdtB leads to cell death is not yet clearly understood. Here, we used Saccharomyces cerevisiae as a model to study the molecular pathways involved in the function of CdtB from Aggregatibacter actinomycetemcomitans, a cause of aggressive periodontitis. We show that A. actinomycetemcomitans CdtB (AaCdtB) expression induces S/G2 arrest and death in a DNase-catalytic residue and nuclear localization-dependent manner in haploid yeasts. Yeast strains defective in homologous recombination (HR) repair, but not other DNA repair pathways, are hypersensitive to AaCdtB, suggesting that HR is required for survival upon CdtB expression. In addition, yeast does not harbor the substrate for the other activity proposed for CdtB function, which is phosphatidylinositol-3,4,5-triphosphate phosphatase. Thus, these results suggest that direct DNA-damaging activity alone is sufficient for CdtB toxicity. To investigate how CdtB induces cell death, we examined the effect of CdtB in yeast strains with mutations in apoptotic regulators. Our results suggest that yeast death occurs independently of the yeast metacaspase gene YCA1 and the apoptosis-inducing factor AIF1 but is partially dependent on histone H2B serine 10 phosphorylation. Therefore, we report here the evidence that AaCdtB causes DNA damage that leads to nonapoptotic death in yeast and the first mutation that confers resistance to CdtB.

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Silencing Sirtuin5 induces DNA damage by suppressing the pentose phosphate pathway in a demalonylation-dependent manner: A possible target for anticancer therapy in CRC

10.21203/rs.3.rs-276003/v1 ◽

2021 ◽

Author(s):

Hao-Lian Wang ◽

Yan Chen ◽

Yun-Qian Wang ◽

En-Wei Tao ◽

Juan Tan ◽

...

Keyword(s):

Cell Cycle ◽

Dna Damage ◽

Cell Cycle Arrest ◽

Pentose Phosphate Pathway ◽

Pentose Phosphate ◽

Dependent Manner ◽

Class Iii ◽

Nucleotide Synthesis ◽

Cycle Arrest

Abstract A previous study by our research group showed that sirtuin5 (SIRT5), a member of the class III NAD＋-dependent deacetylase family, is highly expressed in colorectal cancer (CRC). The present study showed that deletion of SIRT5 induced cell cycle arrest and apoptosis as a result of continuous and irreparable DNA damage in CRC cells, a consequence of the impaired production of ribose-5-phosphate (R5P) which is essential for nucleotide synthesis. Consistently, the cell cycle arrest and apoptosis induced by SIRT5 silencing could be reversed by supplementation with four nucleotides. Moreover, metabolic profiling revealed that silencing of SIRT5 could inhibit the non-oxidative pentose phosphate pathway (PPP), which produces R5P, required for base ribosylation. Notably, SIRT5 activates transketolase (TKT), the key enzyme in the cellular non-oxidative PPP, by mediating its lysine demalonylation through the interaction between SIRT5 and TKT. Furthermore, the results demonstrated that TKT is essential for the SIRT5-induced malignant phenotypes of CRC, both in vivo and in vitro. These results therefore revealed that the increased lysine malonylation levels of TKT caused by silencing SIRT5 suppresses non-oxidative pentose phosphate metabolism, leading to a low-nucleotide pool. This in turn induces DNA damage in tumor cells and inhibits proliferation, suggesting that SIRT5 may serve as a potential anticancer target.

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Pisosterol Induces G2/M Cell Cycle Arrest and Apoptosis via the ATM/ATR Signaling Pathway in Human Glioma Cells

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520620666200203160117 ◽

2020 ◽

Vol 20 (6) ◽

pp. 734-750

Author(s):

Wallax A.S. Ferreira ◽

Rommel R. Burbano ◽

Claudia do Ó. Pessoa ◽

Maria L. Harada ◽

Bárbara do Nascimento Borges ◽

...

Keyword(s):

Cell Cycle ◽

Cell Cycle Arrest ◽

Signaling Pathway ◽

Glioma Cell ◽

Molecular Mechanisms ◽

Glioma Cells ◽

Dependent Manner ◽

M Cell ◽

Trypan Blue Exclusion ◽

Cycle Arrest

Background: Pisosterol, a triterpene derived from Pisolithus tinctorius, exhibits potential antitumor activity in various malignancies. However, the molecular mechanisms that mediate the pisosterol-specific effects on glioma cells remain unknown. Objective: This study aimed to evaluate the antitumoral effects of pisosterol on glioma cell lines. Methods: The 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and trypan blue exclusion assays were used to evaluate the effect of pisosterol on cell proliferation and viability in glioma cells. The effect of pisosterol on the distribution of the cells in the cell cycle was performed by flow cytometry. The expression and methylation pattern of the promoter region of MYC, ATM, BCL2, BMI1, CASP3, CDK1, CDKN1A, CDKN2A, CDKN2B, CHEK1, MDM2, p14ARF and TP53 was analyzed by RT-qPCR, western blotting and bisulfite sequencing PCR (BSP-PCR). Results: Here, it has been reported that pisosterol markedly induced G2/M arrest and apoptosis and decreased the cell viability and proliferation potential of glioma cells in a dose-dependent manner by increasing the expression of ATM, CASP3, CDK1, CDKN1A, CDKN2A, CDKN2B, CHEK1, p14ARF and TP53 and decreasing the expression of MYC, BCL2, BMI1 and MDM2. Pisosterol also triggered both caspase-independent and caspase-dependent apoptotic pathways by regulating the expression of Bcl-2 and activating caspase-3 and p53. Conclusions: It has been, for the first time, confirmed that the ATM/ATR signaling pathway is a critical mechanism for G2/M arrest in pisosterol-induced glioma cell cycle arrest and suggests that this compound might be a promising anticancer candidate for further investigation.

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Design, Synthesis and Pharmacological Evaluation of Three Novel Dehydroabietyl Piperazine Dithiocarbamate Ruthenium (II) Polypyridyl Complexes as Potential Antitumor Agents: DNA Damage, Cell Cycle Arrest and Apoptosis Induction

Molecules ◽

10.3390/molecules26051453 ◽

2021 ◽

Vol 26 (5) ◽

pp. 1453

Author(s):

Haoran Wang ◽

Jianhua Wei ◽

Hong Jiang ◽

Ye Zhang ◽

Caina Jiang ◽

...

Keyword(s):

Cell Cycle ◽

Dna Damage ◽

Cell Cycle Arrest ◽

Antitumor Agents ◽

Mechanistic Study ◽

Ros Generation ◽

Polypyridyl Complexes ◽

Expression Levels ◽

Cycle Arrest ◽

Study Results

The use of cisplatin is severely limited by its toxic side-effects, which has spurred chemists to employ different strategies in the development of new metal-based anticancer agents. Here, three novel dehydroabietyl piperazine dithiocarbamate ruthenium (II) polypyridyl complexes (6a–6c) were synthesized as antitumor agents. Compounds 6a and 6c exhibited better in vitro antiproliferative activity against seven tumor cell lines than cisplatin, they displayed no evident resistance in the cisplatin-resistant cell line A549/DPP. Importantly, 6a effectively inhibited tumor growth in the T-24 xenograft mouse model in comparison with cisplatin. Gel electrophoresis assay indicated that DNA was the potential targets of 6a and 6c, and the upregulation of p-H2AX confirmed this result. Cell cycle arrest studies demonstrated that 6a and 6c arrested the cell cycle at G1 phase, accompanied by the upregulation of the expression levels of the antioncogene p27 and the down-regulation of the expression levels of cyclin E. In addition, 6a and 6c caused the apoptosis of tumor cells along with the upregulation of the expression of Bax, caspase-9, cytochrome c, intracellular Ca2+ release, reactive oxygen species (ROS) generation and the downregulation of Bcl-2. These mechanistic study results suggested that 6a and 6c exerted their antitumor activity by inducing DNA damage, and consequently causing G1 stage arrest and the induction of apoptosis.

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