Molecular Mechanisms that Restrict Yeast Centrosome Duplication to One Event per Cell Cycle

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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Clinical Candidates Targeting the ATR–CHK1–WEE1 Axis in Cancer

Cancers ◽

10.3390/cancers13040795 ◽

2021 ◽

Vol 13 (4) ◽

pp. 795

Author(s):

Lukas Gorecki ◽

Martin Andrs ◽

Jan Korabecny

Keyword(s):

Cell Cycle ◽

Cancer Cells ◽

Molecular Mechanisms ◽

Patient Survival ◽

Current Status ◽

Future Perspectives ◽

Phase Ii Trials ◽

Anticancer Treatment ◽

Positive Outlook ◽

Insight Into

Selective killing of cancer cells while sparing healthy ones is the principle of the perfect cancer treatment and the primary aim of many oncologists, molecular biologists, and medicinal chemists. To achieve this goal, it is crucial to understand the molecular mechanisms that distinguish cancer cells from healthy ones. Accordingly, several clinical candidates that use particular mutations in cell-cycle progressions have been developed to kill cancer cells. As the majority of cancer cells have defects in G1 control, targeting the subsequent intra‑S or G2/M checkpoints has also been extensively pursued. This review focuses on clinical candidates that target the kinases involved in intra‑S and G2/M checkpoints, namely, ATR, CHK1, and WEE1 inhibitors. It provides insight into their current status and future perspectives for anticancer treatment. Overall, even though CHK1 inhibitors are still far from clinical establishment, promising accomplishments with ATR and WEE1 inhibitors in phase II trials present a positive outlook for patient survival.

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LMNB2 promotes the progression of colorectal cancer by silencing p21 expression

Cell Death and Disease ◽

10.1038/s41419-021-03602-1 ◽

2021 ◽

Vol 12 (4) ◽

Author(s):

Chen-Hua Dong ◽

Tao Jiang ◽

Hang Yin ◽

Hu Song ◽

Yi Zhang ◽

...

Keyword(s):

Colorectal Cancer ◽

Cell Cycle ◽

Cell Proliferation ◽

Cell Cycle Progression ◽

Molecular Mechanisms ◽

Gene Set Enrichment Analysis ◽

Molecular Therapy ◽

Cycle Progression ◽

Cancer Tissues

AbstractColorectal cancer is the second common cause of death worldwide. Lamin B2 (LMNB2) is involved in chromatin remodeling and the rupture and reorganization of nuclear membrane during mitosis, which is necessary for eukaryotic cell proliferation. However, the role of LMNB2 in colorectal cancer (CRC) is poorly understood. This study explored the biological functions of LMNB2 in the progression of colorectal cancer and explored the possible molecular mechanisms. We found that LMNB2 was significantly upregulated in primary colorectal cancer tissues and cell lines, compared with paired non-cancerous tissues and normal colorectal epithelium. The high expression of LMNB2 in colorectal cancer tissues is significantly related to the clinicopathological characteristics of the patients and the shorter overall and disease-free cumulative survival. Functional analysis, including CCK8 cell proliferation test, EdU proliferation test, colony formation analysis, nude mouse xenograft, cell cycle, and apoptosis analysis showed that LMNB2 significantly promotes cell proliferation by promoting cell cycle progression in vivo and in vitro. In addition, gene set enrichment analysis, luciferase report analysis, and CHIP analysis showed that LMNB2 promotes cell proliferation by regulating the p21 promoter, whereas LMNB2 has no effect on cell apoptosis. In summary, these findings not only indicate that LMNB2 promotes the proliferation of colorectal cancer by regulating p21-mediated cell cycle progression, but also suggest the potential value of LMNB2 as a clinical prognostic marker and molecular therapy target.

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COXIBs and 2,5-dimethylcelecoxib counteract the hyperactivated Wnt/β-catenin pathway and COX-2/PGE2/EP4 signaling in glioblastoma cells

BMC Cancer ◽

10.1186/s12885-021-08164-1 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Aleksandra Majchrzak-Celińska ◽

Julia O. Misiorek ◽

Nastassia Kruhlenia ◽

Lukasz Przybyl ◽

Robert Kleszcz ◽

...

Keyword(s):

Cell Cycle ◽

Cell Viability ◽

Methylation Level ◽

Molecular Mechanisms ◽

Methylation Status ◽

Receptor Expression ◽

Cell Cycle Distribution ◽

Ep4 Receptor ◽

Cox 2 ◽

The Impact

Abstract Background Glioblastoma (GBM) is the deadliest and the most common primary brain tumor in adults. The invasiveness and proliferation of GBM cells can be decreased through the inhibition of Wnt/β-catenin pathway. In this regard, celecoxib is a promising agent, but other COXIBs and 2,5-dimethylcelecoxib (2,5-DMC) await elucidation. Thus, the aim of this study was to analyze the impact of celecoxib, 2,5-DMC, etori-, rofe-, and valdecoxib on GBM cell viability and the activity of Wnt/β-catenin pathway. In addition, the combination of the compounds with temozolomide (TMZ) was also evaluated. Cell cycle distribution and apoptosis, MGMT methylation level, COX-2 and PGE2 EP4 protein levels were also determined in order to better understand the molecular mechanisms exerted by these compounds and to find out which of them can serve best in GBM therapy. Methods Celecoxib, 2,5-DMC, etori-, rofe- and valdecoxib were evaluated using three commercially available and two patient-derived GBM cell lines. Cell viability was analyzed using MTT assay, whereas alterations in MGMT methylation level were determined using MS-HRM method. The impact of COXIBs, in the presence and absence of TMZ, on Wnt pathway was measured on the basis of the expression of β-catenin target genes. Cell cycle distribution and apoptosis analysis were performed using flow cytometry. COX-2 and PGE2 EP4 receptor expression were evaluated using Western blot analysis. Results Wnt/β-catenin pathway was attenuated by COXIBs and 2,5-DMC irrespective of the COX-2 expression profile of the treated cells, their MGMT methylation status, or radio/chemoresistance. Celecoxib and 2,5-DMC were the most cytotoxic. Cell cycle distribution was altered, and apoptosis was induced after the treatment with celecoxib, 2,5-DMC, etori- and valdecoxib in T98G cell line. COXIBs and 2,5-DMC did not influence MGMT methylation status, but inhibited COX-2/PGE2/EP4 pathway. Conclusions Not only celecoxib, but also 2,5-DMC, etori-, rofe- and valdecoxib should be further investigated as potential good anti-GBM therapeutics.

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MODEL-BASED IDENTIFICATION AND ADAPTIVE CONTROL OF THE CORE MODULE IN A TYPICAL CELL CYCLE PATHWAY VIA NETWORK AND SYSTEM CONTROL THEORIES

Advances in Complex Systems ◽

10.1142/s0219525909002076 ◽

2009 ◽

Vol 12 (01) ◽

pp. 21-43 ◽

Cited By ~ 4

Author(s):

BINHUA TANG ◽

LI HE ◽

QING JING ◽

BAIRONG SHEN

Keyword(s):

Cell Cycle ◽

Adaptive Control ◽

Molecular Mechanisms ◽

Cell Cycle Control ◽

System Control ◽

Core Module ◽

Typical Cell ◽

And Performance ◽

Control Theories

The loss of cell cycle control is often associated with cancers and other different diseases. With the accumulation of omics data, the network for molecule interactions in the cell cycle process will become much clearer. The identification of the crucial modules in a giant network and investigation of inherent control relations are very important to the understanding of the molecular mechanisms of diseases for new drug design. The paper proposes novel techniques in analyzing such core regulatory modules based on network and system control theories. We initially define the degree of participation (DOP) and the rate of activity (ROA) for indentifying core module components, and then the diverse contribution elasticity functions for quantifying pairwise regulatory or control activities between those components, thus facilitating the decomposition of expanded core modules and the formation of feedback loops within the control schema. Motivated by the inherent regulatory mechanisms, we expound a kind of multiphase nonlinear adaptive control algorithm in repelling abnormal genetic mutations, which directly and indirectly impact cancer development in biological cells and organs. Experimental predictions are also elucidated within the work, helping those in vivo design, verification and performance evaluation.

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S-Phase Cell Cycle Arrest, Apoptosis, and Molecular Mechanisms of Aplasia Ras homolog Member I–Induced Human Ovarian Cancer SKOV3 Cell Lines

International Journal of Gynecological Cancer ◽

10.1097/igc.0000000000000105 ◽

2014 ◽

Vol 24 (4) ◽

pp. 629-634 ◽

Cited By ~ 10

Author(s):

Qiaoying Zhu ◽

Jianming Hu ◽

Huijuan Meng ◽

Yufei Shen ◽

Jinhua Zhou ◽

...

Keyword(s):

Cell Cycle ◽

Ovarian Cancer ◽

Molecular Mechanisms ◽

Significant Inhibition ◽

S Phase ◽

Phase Cell ◽

Cell Cycle Distribution ◽

Human Ovarian Cancer ◽

Skov3 Cell ◽

Skov3 Cells

ObjectiveAplasia Ras homolog member I (ARHI) is associated with human ovarian cancer (HOC) growth and proliferation; however, the mechanisms are unclear. The purpose of this study was to investigateARHIeffects in HOC SKOV3 cells.MethodsWe transfected SKOV3 cells with PIRES2-EGFP-ARHI and measured growth inhibition rates, cell cycle distribution, apoptosis rates, and expression of P-STAT3 (phosphorylated signal transduction and activators of transcription 3) and P-ERK (phosphorylated extracellular signal regulated protein kinase).ResultsOur data showed significant inhibition of growth, significantly increased S-phase arrest and apoptosis rates, and reduction of P-STAT3 and P-ERK1/2 expression levels.ConclusionsWe propose the mechanism may involveARHI-induced phosphorylation of ERK1/2 and STAT3 protein kinases, thereby blocking proliferation signaling pathways, to induce HOC SKOV3 apoptosis.

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Phosphorylation of Centrin during the Cell Cycle and Its Role in Centriole Separation Preceding Centrosome Duplication

Journal of Biological Chemistry ◽

10.1074/jbc.m101324200 ◽

2001 ◽

Vol 276 (23) ◽

pp. 20774-20780 ◽

Cited By ~ 79

Author(s):

Ward Lutz ◽

Wilma L. Lingle ◽

Daniel McCormick ◽

Tammy M. Greenwood ◽

Jeffrey L. Salisbury

Keyword(s):

Cell Cycle ◽

Centrosome Duplication

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mTOR function in skeletal muscle hypertrophy: increased ribosomal RNA via cell cycle regulators

AJP Cell Physiology ◽

10.1152/ajpcell.00165.2005 ◽

2005 ◽

Vol 289 (6) ◽

pp. C1457-C1465 ◽

Cited By ~ 104

Author(s):

Gustavo A. Nader ◽

Thomas J. McLoughlin ◽

Karyn A. Esser

Keyword(s):

Cell Cycle ◽

Protein Expression ◽

Cyclin D1 ◽

Ribosomal Rna ◽

Molecular Mechanisms ◽

D1 Protein ◽

Rna Content ◽

Cyclin D1 Protein ◽

Rb Phosphorylation ◽

Myotube Hypertrophy

The purpose of this study was to identify the potential downstream functions associated with mammalian target of rapamycin (mTOR) signaling during myotube hypertrophy. Terminally differentiated myotubes were serum stimulated for 3, 6, 12, 24, and 48 h. This treatment resulted in significant myotube hypertrophy (protein/DNA) and increased RNA content (RNA/DNA) with no changes in DNA content or indices of cell proliferation. During myotube hypertrophy, the increase in RNA content was accompanied by an increase in tumor suppressor protein retinoblastoma (Rb) phosphorylation and a corresponding increase in the availability of the ribosomal DNA transcription factor upstream binding factor (UBF). Serum stimulation also induced an increase in cyclin D1 protein expression in the differentiated myotubes with a concomitant increase in cyclin D1-dependent cyclin-dependent kinase (CDK)-4 activity toward Rb. The increases in myotube hypertrophy and RNA content were blocked by rapamycin treatment, which also prevented the increase in cyclin D1 protein expression, CDK-4 activity, Rb phosphorylation, and the increase in UBF availability. Our findings demonstrate that activation of mTOR is necessary for myotube hypertrophy and suggest that the role of mTOR is in part to modulate cyclin D1-dependent CDK-4 activity in the regulation of Rb and ribosomal RNA synthesis. On the basis of these results, we propose that common molecular mechanisms contribute to the regulation of myotube hypertrophy and growth during the G1 phase of the cell cycle.

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