Modulation of STAT3 Signaling, Cell Redox Defenses and Cell Cycle Checkpoints by β-Caryophyllene in Cholangiocarcinoma Cells: Possible Mechanisms Accounting for Doxorubicin Chemosensitization and Chemoprevention

Cholangiocarcinoma (CCA) is an aggressive group of biliary tract cancers, characterized by late diagnosis, low effective chemotherapies, multidrug resistance, and poor outcomes. In the attempt to identify new therapeutic strategies for CCA, we studied the antiproliferative activity of a combination between doxorubicin and the natural sesquiterpene β-caryophyllene in cholangiocarcinoma Mz-ChA-1 cells and nonmalignant H69 cholangiocytes, under both long-term and metronomic schedules. The modulation of STAT3 signaling, oxidative stress, DNA damage response, cell cycle progression and apoptosis was investigated as possible mechanisms of action. β-caryophyllene was able to synergize the cytotoxicity of low dose doxorubicin in Mz-ChA-1 cells, while producing cytoprotective effects in H69 cholangiocytes, mainly after a long-term exposure of 24 h. The mechanistic analysis highlighted that the sesquiterpene induced a cell cycle arrest in G2/M phase along with the doxorubicin-induced accumulation in S phase, reduced the γH2AX and GSH levels without affecting GSSG. ROS amount was partly lowered by the combination in Mz-ChA-1 cells, while increased in H69 cells. A lowered expression of doxorubicin-induced STAT3 activation was found in the presence of β-caryophyllene in both cancer and normal cholangiocytes. These networking effects resulted in an increased apoptosis rate in Mz-ChA-1 cells, despite a lowering in H69 cholangiocytes. This evidence highlighted a possible role of STAT3 as a final effector of a complex network regulated by β-caryophyllene, which leads to an enhanced doxorubicin-sensitivity of cholangiocarcinoma cells and a lowered chemotherapy toxicity in nonmalignant cholangiocytes, thus strengthening the interest for this natural sesquiterpene as a dual-acting chemosensitizing and chemopreventive agent.

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Antiproliferative Effect of Dihydroxyacetone on Trypanosoma brucei Bloodstream Forms: Cell Cycle Progression, Subcellular Alterations, and Cell Death

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00423-07 ◽

2007 ◽

Vol 51 (11) ◽

pp. 3960-3968 ◽

Cited By ~ 27

Author(s):

Néstor L. Uzcátegui ◽

Didac Carmona-Gutiérrez ◽

Viola Denninger ◽

Caroline Schoenfeld ◽

Florian Lang ◽

...

Keyword(s):

Energy Source ◽

Cell Cycle ◽

Trypanosoma Brucei ◽

Rational Design ◽

Cell Cycle Progression ◽

Cell Types ◽

Cycle Arrest ◽

Starting Point ◽

M Phase ◽

Different Cell Types

ABSTRACT We evaluated the effects of dihydroxyacetone (DHA) on Trypanosoma brucei bloodstream forms. DHA is considered an energy source for many different cell types. T. brucei takes up DHA readily due to the presence of aquaglyceroporins. However, the parasite is unable to use it as a carbon source because of the absence of DHA kinase (DHAK). We could not find a homolog of the relevant gene in the genomic database of T. brucei and have been unable to detect DHAK activity in cell lysates of the parasite, and the parasite died quickly if DHA was the sole energy source in the medium. In addition, during trypanosome cultivation, DHA induced growth inhibition with a 50% inhibitory concentration of about 1 mM, a concentration that is completely innocuous to mammals. DHA caused cell cycle arrest in the G2/M phase of up to 70% at a concentration of 2 mM. Also, DHA-treated parasites showed profound ultrastructural alterations, including an increase of vesicular structures within the cytosol and the presence of multivesicular bodies, myelin-like structures, and autophagy-like vacuoles, as well as a marked disorder of the characteristic mitochondrion structure. Based on the toxicity of DHA for trypanosomes compared with mammals, we consider DHA a starting point for a rational design of new trypanocidal drugs.

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Ddb1 Is Essential for the Expansion of CD4+ Helper T Cells by Regulating Cell Cycle Progression and Cell Death

Frontiers in Immunology ◽

10.3389/fimmu.2021.722273 ◽

2021 ◽

Vol 12 ◽

Author(s):

Lingtao Yang ◽

Wei Chen ◽

Li Li ◽

Yueyue Xiao ◽

Shilin Fan ◽

...

Keyword(s):

Cell Cycle ◽

T Cells ◽

Cell Death ◽

Cell Cycle Progression ◽

Helper T Cells ◽

Genome Maintenance ◽

Cycle Arrest ◽

Follicular Helper ◽

Acute Viral Infection ◽

M Phase

Follicular helper T (TFH) cells are specialized CD4+ helper T cells that provide help to B cells in humoral immunity. However, the molecular mechanism underlying generation of TFH cells is incompletely understood. Here, we reported that Damage-specific DNA binding protein 1 (Ddb1) was required for expansion of CD4+ helper T cells including TFH and Th1 cells, germinal center response, and antibody response to acute viral infection. Ddb1 deficiency in activated CD4+ T cells resulted in cell cycle arrest at G2-M phase and increased cell death, due to accumulation of DNA damage and hyperactivation of ATM/ATR-Chk1 signaling. Moreover, mice with deletion of both Cul4a and Cul4b in activated CD4+ T cells phenocopied Ddb1-deficient mice, suggesting that E3 ligase-dependent function of Ddb1 was crucial for genome maintenance and helper T-cell generation. Therefore, our results indicate that Ddb1 is an essential positive regulator in the expansion of CD4+ helper T cells.

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Energy Starvation Induces a Cell Cycle Arrest in Escherichia coli by Triggering Degradation of the DnaA Initiator Protein

Frontiers in Molecular Biosciences ◽

10.3389/fmolb.2021.629953 ◽

2021 ◽

Vol 8 ◽

Author(s):

Godefroid Charbon ◽

Belén Mendoza-Chamizo ◽

Christopher Campion ◽

Xiaobo Li ◽

Peter Ruhdal Jensen ◽

...

Keyword(s):

Escherichia Coli ◽

Cell Cycle ◽

Growth Conditions ◽

Chromosome Replication ◽

Replication Initiation ◽

Atp Depletion ◽

Initiator Protein ◽

Cycle Arrest ◽

A Cell

During steady-state Escherichia coli growth, the amount and activity of the initiator protein, DnaA, controls chromosome replication tightly so that initiation only takes place once per origin in each cell cycle, regardless of growth conditions. However, little is known about the mechanisms involved during transitions from one environmental condition to another or during starvation stress. ATP depletion is one of the consequences of long-term carbon starvation. Here we show that DnaA is degraded in ATP-depleted cells. A chromosome replication initiation block is apparent in such cells as no new rounds of DNA replication are initiated while replication events that have already started proceed to completion.

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Histone supply regulates S phase timing and cell cycle progression

eLife ◽

10.7554/elife.02443 ◽

2014 ◽

Vol 3 ◽

Cited By ~ 33

Author(s):

Ufuk Günesdogan ◽

Herbert Jäckle ◽

Alf Herzig

Keyword(s):

Cell Cycle ◽

Cell Cycle Progression ◽

De Novo ◽

S Phase ◽

Histone Genes ◽

Nucleosome Assembly ◽

Cycle Progression ◽

Cycle Arrest ◽

A Cell ◽

Surveillance Mechanism

Eukaryotes package DNA into nucleosomes that contain a core of histone proteins. During DNA replication, nucleosomes are disrupted and re-assembled with newly synthesized histones and DNA. Despite much progress, it is still unclear why higher eukaryotes contain multiple core histone genes, how chromatin assembly is controlled, and how these processes are coordinated with cell cycle progression. We used a histone null mutation of Drosophila melanogaster to show that histone supply levels, provided by a defined number of transgenic histone genes, regulate the length of S phase during the cell cycle. Lack of de novo histone supply not only extends S phase, but also causes a cell cycle arrest during G2 phase, and thus prevents cells from entering mitosis. Our results suggest a novel cell cycle surveillance mechanism that monitors nucleosome assembly without involving the DNA repair pathways and exerts its effect via suppression of CDC25 phosphatase String expression.

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Synthesis of 2,6-Diamino-Substituted Purine Derivatives and Evaluation of Cell Cycle Arrest in Breast and Colorectal Cancer Cells

Molecules ◽

10.3390/molecules23081996 ◽

2018 ◽

Vol 23 (8) ◽

pp. 1996 ◽

Cited By ~ 3

Author(s):

Bartolomeo Bosco ◽

Andrea Defant ◽

Andrea Messina ◽

Tania Incitti ◽

Denise Sighel ◽

...

Keyword(s):

Colorectal Cancer ◽

Cell Cycle ◽

Cell Cycle Arrest ◽

Cancer Cells ◽

Cell Lines ◽

Cancer Cell ◽

Density Functional ◽

Cell Cycle Progression ◽

Cycle Arrest ◽

M Phase

Reversine is a potent antitumor 2,6-diamino-substituted purine acting as an Aurora kinases inhibitor and interfering with cancer cell cycle progression. In this study we describe three reversine-related molecules, designed by docking calculation, that present structural modifications in the diamino units at positions 2 and 6. We investigated the conformations of the most stable prototropic tautomers of one of these molecules, the N6-cyclohexyl-N6-methyl-N2-phenyl-7H-purine-2,6-diamine (3), by Density Functional Theory (DFT) calculation in the gas phase, water and chloroform, the last solvent considered to give insights into the detection of broad signals in NMR analysis. In all cases the HN(9) tautomer resulted more stable than the HN(7) form, but the most stable conformations changed in different solvents. Molecules 1–3 were evaluated on MCF-7 breast and HCT116 colorectal cancer cell lines showing that, while being less cytotoxic than reversine, they still caused cell cycle arrest in G2/M phase and polyploidy. Unlike reversine, which produced a pronounced cell cycle arrest in G2/M phase in all the cell lines used, similar concentrations of 1–3 were effective only in cells where p53 was deleted or down-regulated. Therefore, our findings support a potential selective role of these structurally simplified, reversine-related molecules in p53-defective cancer cells.

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CRISPR/Cas9 treatment causes extended TP53-dependent cell cycle arrest in human cells

Nucleic Acids Research ◽

10.1093/nar/gkaa603 ◽

2020 ◽

Vol 48 (16) ◽

pp. 9067-9081

Author(s):

Jonathan M Geisinger ◽

Tim Stearns

Keyword(s):

Cell Cycle ◽

Cell Cycle Arrest ◽

Cell Lines ◽

Cell Cycle Progression ◽

Target Sequence ◽

Wild Type ◽

Cycle Progression ◽

Cycle Arrest ◽

Dependent Cell ◽

A Cell

Abstract While the mechanism of CRISPR/Cas9 cleavage is understood, the basis for the large variation in mutant recovery for a given target sequence between cell lines is much less clear. We hypothesized that this variation may be due to differences in how the DNA damage response affects cell cycle progression. We used incorporation of EdU as a marker of cell cycle progression to analyze the response of several human cell lines to CRISPR/Cas9 treatment with a single guide directed to a unique locus. Cell lines with functionally wild-type TP53 exhibited higher levels of cell cycle arrest compared to lines without. Chemical inhibition of TP53 protein combined with TP53 and RB1 transcript silencing alleviated induced arrest in TP53+/+ cells. Using dCas9, we determined this arrest is driven in part by Cas9 binding to DNA. Additionally, wild-type Cas9 induced fewer 53BP1 foci in TP53+/+ cells compared to TP53−/− cells and DD-Cas9, suggesting that differences in break sensing are responsible for cell cycle arrest variation. We conclude that CRISPR/Cas9 treatment induces a cell cycle arrest dependent on functional TP53 as well as Cas9 DNA binding and cleavage. Our findings suggest that transient inhibition of TP53 may increase genome editing recovery in primary and TP53+/+ cell lines.

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Selenium supplementation protects against oxidative stress-induced cardiomyocyte cell cycle arrest through activation of PI3K/AKT

Metallomics ◽

10.1039/d0mt00225a ◽

2020 ◽

Author(s):

Wenjuan Sun ◽

Jiawei Zhu ◽

Shuang Li ◽

Chaohua Tang ◽

Qingyu Zhao ◽

...

Keyword(s):

Oxidative Stress ◽

Cell Cycle ◽

Cell Cycle Arrest ◽

Cell Cycle Progression ◽

Inhibitory System ◽

Cycle Progression ◽

Cycle Arrest ◽

System P ◽

M Phase ◽

Promote Cell Cycle Progression

Selenium alleviates oxidative stress-induced cell cycle arrest in cardiomyocytes mediated by antioxidant capacity of selenoproteins, thus activating PI3K/AKT pathways, which promote cell cycle progression by targeting the G2/M phase inhibitory system.

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Cyclization of flavokawain B reduces its activity against human colon cancer cells

Human & Experimental Toxicology ◽

10.1177/0960327119882986 ◽

2019 ◽

Vol 39 (3) ◽

pp. 262-275 ◽

Cited By ~ 3

Author(s):

A Palko-Łabuz ◽

E Kostrzewa-Susłow ◽

T Janeczko ◽

K Środa-Pomianek ◽

A Poła ◽

...

Keyword(s):

Cell Cycle ◽

Cancer Cells ◽

Cell Cycle Progression ◽

Structural Parameters ◽

Human Colon ◽

Human Colon Cancer ◽

Cycle Arrest ◽

Biological Studies ◽

M Phase ◽

Induced Apoptosis

Chalcones are naturally occurring compounds exhibiting biological activity through multiple mechanisms. Flavokawain B is one of chalcones found in kava plant. In our studies, we focused on the anticancer activity of flavokawain B in colorectal cancer cells LoVo and its resistant to doxorubicin subline—LoVo/Dx. Strong cytotoxic activity of flavokawain B and its ability to inhibit the proliferation in both cell lines was detected. These effects accompanied with induction cell cycle arrest in G2/M phase and the presence of SubG1 fraction. Flavokawain B at low concentration led to increase of caspase-3 activity. The chalcone-induced apoptosis was also confirmed by DNA fragmentation. In our work, the conversion of flavokawain B to corresponding flavanone—5,7-dimetoxyflavanone—was shown to be more extensive in cancer than in non-cancer cells. We found that the cyclization of the chalcone was related to the significant decrease in the cytotoxicity. Cell proliferation and cell cycle progression were not impaired significantly in the studied cancer cells incubated with 5,7-dimethoxyflavanone. We did not observe apoptosis in the cells incubated with flavanone. The results from biological studies agreed with the theoretical activity that emerges from structural parameters.

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BmFoxO Gene Regulation of the Cell Cycle Induced by 20-Hydroxyecdysone in BmN-SWU1 Cells

Insects ◽

10.3390/insects11100700 ◽

2020 ◽

Vol 11 (10) ◽

pp. 700

Author(s):

Qian Zhang ◽

Jigui Yang ◽

Peng Chen ◽

Taihang Liu ◽

Qin Xiao ◽

...

Keyword(s):

Cell Cycle ◽

Dna Replication ◽

Cell Cycle Progression ◽

Nuclear Translocation ◽

G1 Phase ◽

Ecdysone Receptor ◽

Cycle Progression ◽

Cycle Arrest ◽

Cell Accumulation ◽

M Phase

Ecdysteroid titer determines the state of the cell cycle in silkworm (Bombyxmori) metamorphosis. However, the mechanism of this process is unclear. In this study, we demonstrated that the BmFoxO gene participates in the regulation of the cell cycle induced by 20-Hydroxyecdysone (20E) in BmN-SWU1 cells. The 20E blocks the cell cycle in the G2/M phase through the ecdysone receptor (EcR) and inhibits DNA replication. The 20E can promote BmFoxO gene expression. Immunofluorescence and Western blot results indicated that 20E can induce BmFoxO nuclear translocation in BmN-SWU1 cells. Overexpression of the BmFoxO gene affects cell cycle progression, which results in cell cycle arrest in the G0/G1 phase as well as inhibition of DNA replication. Knockdown of the BmFoxO gene led to cell accumulation at the G2/M phase. The effect of 20E was attenuated after BmFoxO gene knockdown. These findings increase our understanding of the function of 20E in the regulation of the cell cycle in B. mori.

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The Checkpoint Protein Rad24 of Saccharomyces cerevisiae Is Involved in Processing Double-Strand Break Ends and in Recombination Partner Choice

Molecular and Cellular Biology ◽

10.1128/mcb.23.18.6585-6596.2003 ◽

2003 ◽

Vol 23 (18) ◽

pp. 6585-6596 ◽

Cited By ~ 41

Author(s):

Yael Aylon ◽

Martin Kupiec

Keyword(s):

Cell Cycle ◽

Cell Cycle Progression ◽

Strand Break ◽

Double Strand Break ◽

Partner Choice ◽

Checkpoint Response ◽

Checkpoint Protein ◽

Cycle Arrest ◽

M Phase ◽

Kinetics Of

ABSTRACT Upon chromosomal damage, cells activate a checkpoint response that includes cell cycle arrest and a stimulation of DNA repair. The checkpoint protein Rad24 is key to the survival of a single, repairable double-strand break (DSB). However, the low survival of rad24 cells is not due to their inability to arrest cell cycle progression. In rad24 mutants, processing of the broken ends is delayed and protracted, resulting in extended kinetics of DSB repair and in cell death. The limited resection of rad24 mutants also affects recombination partner choice by a mechanism dependent on the length of the interacting homologous donor sequences. Unexpectedly, rad24 cells with a DSB eventually accumulate and die at the G2/M phase of the cell cycle. This arrest depends on the spindle checkpoint protein Mad2.

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