Identification of Cell Cycle Models by Flow Cytometry

1994 ◽  
Vol 27 (1) ◽  
pp. 421-422
Author(s):  
Lorenzo Cazzador ◽  
Luigi Mariani
Keyword(s):  
Cell Cycle ◽  
Flow Cytometry ◽  
Cell Cycle Models

A Novel Camptothecin Derivative 3j Inhibits Nsclc Proliferation Via Induction of Cell Cycle Arrest By Topo I-Mediated DNA Damage

2019 ◽  
Vol 19 (3) ◽  
pp. 365-374 ◽  
Author(s):  
Yang Liu ◽  
Jingyin Zhang ◽  
Shuyun Feng ◽  
Tingli Zhao ◽  
Zhengzheng Li ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Flow Cytometry ◽  
Dna Damage ◽  
Cyclin D ◽  
Dna Relaxation ◽  
Cycle Arrest ◽  
H460 Cell ◽  
H1975 Cell

Objective: The aim of this study is to investigate the inhibitory effect of camptothecin derivative 3j on Non-Small Cell Lung Cancer (NSCLCs) cells and the potential anti-tumor mechanisms. Background: Camptothecin compounds are considered as the third largest natural drugs which are widely investigated in the world and they suffered restriction because of serious toxicity, such as hemorrhagic cystitis and bone marrow suppression. Methods: Using cell proliferation assay and S180 tumor mice model, a series of 20(S)-O-substituted benzoyl 7- ethylcamptothecin compounds were screened and evaluated the antitumor activities in vitro and in vivo. Camptothecin derivative 3j was selected for further study using flow cytometry in NSCLCs cells. Cell cycle related protein cyclin A2, CDK2, cyclin D and cyclin E were detected by Western Blot. Then, computer molecular docking was used to confirm the interaction between 3j and Topo I. Also, DNA relaxation assay and alkaline comet assay were used to investigate the mechanism of 3j on DNA damage. Results: Our results demonstrated that camptothecin derivative 3j showed a greater antitumor effect in eleven 20(S)-O-substituted benzoyl 7-ethylcamptothecin compounds in vitro and in vivo. The IC50 of 3j was 1.54± 0.41 µM lower than irinotecan with an IC50 of 13.86±0.80 µM in NCI-H460 cell, which was reduced by 8 fold. In NCI-H1975 cell, the IC50 of 3j was 1.87±0.23 µM lower than irinotecan (IC50±SD, 5.35±0.38 µM), dropped by 1.8 fold. Flow cytometry analysis revealed that 3j induced significant accumulation in a dose-dependent manner. After 24h of 3j (10 µM) treatment, the percentage of NCI-H460 cell in S-phase significantly increased (to 93.54 ± 4.4%) compared with control cells (31.67 ± 3.4%). Similarly, the percentage of NCI-H1975 cell in Sphase significantly increased (to 83.99 ± 2.4%) compared with control cells (34.45 ± 3.9%) after treatment with 10µM of 3j. Moreover, increased levels of cyclin A2, CDK2, and decreased levels of cyclin D, cyclin E further confirmed that cell cycle arrest was induced by 3j. Furthermore, molecular docking studies suggested that 3j interacted with Topo I-DNA and DNA-relaxation assay simultaneously confirmed that 3j suppressed the activity of Topo I. Research on the mechanism showed that 3j exhibited anti-tumour activity via activating the DNA damage response pathway and suppressing the repair pathway in NSCLC cells. Conclusion: Novel camptothecin derivative 3j has been demonstrated as a promising antitumor agent and remains to be assessed in further studies.

Cell Cycle-specific Measurement of γH2AX and Apoptosis After Genotoxic Stress by Flow Cytometry

10.3791/59968 ◽  
2019 ◽  
Author(s):  
Ramon Lopez Perez ◽  
Franziska Münz ◽  
Jonas Kroschke ◽  
Jannek Brauer ◽  
Nils H. Nicolay ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Flow Cytometry ◽  
Genotoxic Stress ◽  
Specific Measurement

scholarly journals Costunolide Induces Apoptosis via the Reactive Oxygen Species and Protein Kinase B Pathway in Oral Cancer Cells

2021 ◽  
Vol 22 (14) ◽  
pp. 7509
Author(s):  
Hai Huang ◽  
Jun-Koo Yi ◽  
Su-Geun Lim ◽  
Sijun Park ◽  
Haibo Zhang ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Cell Cycle ◽  
Flow Cytometry ◽  
Oral Cancer ◽  
Cancer Cells ◽  
Reactive Oxygen ◽  
Migration And Invasion ◽  
Oxygen Species ◽  
Oral Cancer Cells

Oral cancer (OC) has been attracted research attention in recent years as result of its high morbidity and mortality. Costunolide (CTD) possesses potential anticancer and bioactive abilities that have been confirmed in several types of cancers. However, its effects on oral cancer remain unclear. This study investigated the potential anticancer ability and underlying mechanisms of CTD in OC in vivo and in vitro. Cell viability and anchorage-independent colony formation assays were performed to examine the antigrowth effects of CTD on OC cells; assessments for migration and invasion of OC cells were conducted by transwell; Cell cycle and apoptosis were investigated by flow cytometry and verified by immunoblotting. The results revealed that CTD suppressed the proliferation, migration and invasion of oral cancer cells effectively and induced cell cycle arrest and apoptosis; regarding the mechanism, CTD bound to AKT directly by binding assay and repressed AKT activities through kinase assay, which thereby downregulating the downstream of AKT. Furthermore, CTD remarkably promotes the generation of reactive oxygen species by flow cytometry assay, leading to cell apoptosis. Notably, CTD strongly suppresses cell-derived xenograft OC tumor growth in an in vivo mouse model. In conclusion, our results suggested that costunolide might prevent progression of OC and promise to be a novel AKT inhibitor.

scholarly journals Effect of Placental Extract on Omentum Mesenchymal Stem Cells Differentiation in NMRI Mice

2017 ◽  
Vol 7 (1) ◽  
pp. 176
Author(s):  
Maryam Sadat Nezhadfazel ◽  
Kazem Parivar ◽  
Nasim Hayati Roodbari ◽  
Mitra Heydari Nasrabadi
Keyword(s):  
Cell Cycle ◽  
Stem Cells ◽  
Flow Cytometry ◽  
Endothelial Cells ◽  
Mesenchymal Stem Cells ◽  
Control Group ◽  
Fat Cell ◽  
Nmri Mice ◽  
Differentiated Cells ◽  
Placental Extract

Omentum mesenchymal stem cells (OMSCs) could be induced to differentiate into cell varieties under certain conditions. We studied differentiation of OMSCs induced by using placenta extract in NMRI mice. Mesenchymal stem cells (MSCs) were isolated from omentum and cultured with mice placenta extract. MSCs, were assessed after three passages by flow cytometry for CD90, CD44, CD73, CD105, CD34 markers and were recognized their ability to differentiate into bone and fat cell lines. Placenta extract dose was determined with IC50 test then OMSCs were cultured in DMEM and 20% placenta extract.The cell cycle was checked. OMSCs were assayed on 21 days after culture and differentiated cells were determined by flow cytometry and again processed for flow cytometry. CD90, CD44, CD73, CD105 markers were not expressed, only CD34 was their marker. OMSCs were morphologically observed. Differentiated cells are similar to the endothelial cells. Therefore, to identify differentiated cells, CD31 and FLK1 expression were measured. This was confirmed by its expression. G1 phase of the cell cycle shows that OMSCs compared to the control group, were in the differentiation phase. The reason for the differentiation of MSCs into endothelial cells was the sign of presence of VEGF factor in the medium too high value of as a VEGF secreting source.

scholarly journals Alantolactone pyrazoline analogue inhibits cancer cell proliferation and induces apoptosis in non-small cell lung carcinoma cells

2015 ◽  
Vol 10 (2) ◽  
pp. 409 ◽  
Author(s):  
Jing Lv ◽  
Ming-Qin Cao ◽  
Jian-Chun Yu
Keyword(s):  
Cell Cycle ◽  
Flow Cytometry ◽  
Cell Cycle Arrest ◽  
Chromatin Condensation ◽  
Small Cell ◽  
Small Cell Lung ◽  
Cell Lung Carcinoma ◽  
Cycle Arrest ◽  
H460 Cells ◽  
Dose Dependent

<p>The aim of the current study was to evaluate the anticancer and apoptotic effects of alantolactone pyrazoline analogue in human non-small cell lung cancer (NCI-H460) cells. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetra-zolium bromide) assay was used to evaluate the cell viability while as fluorescence microscopy was used to assess the effect on apoptosis, cellular and nuclear morphology. Flow cytometry evaluated the effect of APA on cell cycle arrest in these cells. The results revealed that APA induced potent, time and dose-dependent cytotoxic effects on the growth of NCI-H460 cells. It also inhibited colony forming tendency as well as cell invasion capability of these cancer cells. APA induced dose-dependent nuclear and cellular morphological effects including chromatin condensation and DNA fragmentation. Flow cytometry revealed that the anticancer effects of APA might be due to its cell cycle arrest inducing tendency in G0/G1 phase of the cell cycle.</p>

scholarly journals Finding the Binding Site of Peloruside A and its Secondary Effects in Saccharomyces Cerevisiae using a  Chemical Genetics Approach

2021 ◽  
Author(s):  
◽  
Reem Hanna
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
Amino Acids ◽  
Flow Cytometry ◽  
Binding Site ◽  
Mammalian Cells ◽  
Site Directed Mutagenesis ◽  
Directed Mutagenesis ◽  
Peloruside A ◽  
Microtubule Function

<p>Peloruside A, a natural product isolated from the marine sponge Mycale hentscheli, is a microtubule-stabilising agent that has a similar mechanism of action to the anticancer drug paclitaxel and is cytotoxic to cultured mammalian cells. Peloruside appears to bind to a distinct site on mammalian tubulin that is different from that of the taxoid-site drugs. Because of the high sequence homology between yeast and mammalian tubulin, Saccharomyces cerevisiae (S. cerevisiae) was used as a model organism to characterise the peloruside-binding site with the aim of advancing our understanding about this site on mammalian tubulin. Wild type S. cerevisiae (BY4741) was sensitive to peloruside at uM concentrations; however, a strain that lacks the mad2 (Mitotic Arrest Deficient 2) gene showed increased sensitivity to the drug at much lower uM concentrations. This gene is a component of the spindle-assembly checkpoint complex that delays the onset of anaphase in cells with defects in mitotic spindle assembly. The main aims of this project were to define the binding site of peloruside A using yeast tubulin to see if microtubule function and/or morphology is altered in yeast by peloruside, and to identify any secondary drug targets "friends of the target" through chemical genetic interactions profiling (Homozygous deletion profiling microarray). Site-directed mutagenesis was used to mutate two conserved amino acids (A296T; R306H) known to confer resistance to peloruside in mammalian cells. Based on a published computer model of the peloruside binding site on mammalian tubulin, we also mutated three other amino acids, two that were predicted to affect peloruside binding (Q291M and N337L), and one that was predicted to affect laulimalide binding but have little affect on peloruside binding (V333W). We also included a negative control that was predicted to have no effect on peloruside binding (R282Q) and would affect epothilone binding. We found that of the six point mutations, only Q291M failed to confer resistance in yeast and instead it increased the inhibition to the drug. Using a bud index assay, confocal microscopy, and flow cytometry, 40-50 uM peloruside was shown to block cells in G2/M of the cell cycle, confirming a direct action of the drug on microtubule function. Homozygous profiling (HOP) microarray analysis of a deletion mutant set of yeast genes was also carried out to identify gene products that interact with peloruside in order to link the drug to specific networks or biochemical pathways in the cells. From site-directed mutagenesis, we concluded that peloruside binds to yeast B-tubulin in the region predicted by the published model of the binding site, and therefore mapping the site on yeast tubulin could provide useful information about the mammalian binding site for peloruside. The bud index, flow cytometry, and confocal microscopy experiments provided further evidence that peloruside interacts with yeast tubulin. From HOP we found that peloruside has roles in the cell cycle, as expected, and has effects on protein transport, secretion, cell wall synthesis, and steroid biosynthesis pathways.</p>

scholarly journals Radiation-induced cell cycle perturbations: a computational tool validated with flow-cytometry data

2020 ◽  
Author(s):  
Leonardo Lonati ◽  
Sofia Barbieri ◽  
Isabella Guardamagna ◽  
Andrea Ottolenghi ◽  
Giorgio Baiocco
Keyword(s):  
Cell Cycle ◽  
Flow Cytometry ◽  
Ionizing Radiation ◽  
Radiation Exposure ◽  
Cell Cycle Progression ◽  
Model Parameters ◽  
Clinical Use ◽  
Transition Rates ◽  
Computational Tool ◽  
Cycle Progression

AbstractCell cycle progression can be studied with computational models that allow to describe and predict its perturbation by agents as ionizing radiation or drugs. Such models can then be integrated in tools for pre-clinical/clinical use, e.g. to optimize kinetically-based administration protocols of radiation therapy and chemotherapy.We present a deterministic compartmental model, specifically reproducing how cells that survive radiation exposure are distributed in the cell cycle as a function of dose and time after exposure. Model compartments represent the four cell-cycle phases, as a fuction of DNA content and time. A system of differential equations, whose parameters represent transition rates, division rate and DNA synthesis rate, describes the temporal evolution. Initial model inputs are data from unexposed cells in exponential growth. Perturbation is implemented as an alteration of model parameters that allows to best reproduce cell-cycle profiles post-irradiation. The model is validated with dedicated in vitro measurements on human lung fibroblasts (IMR90). Cells were irradiated with 2 and 5 Gy with a Varian 6 MV Clinac at IRCCS Maugeri. Flow cytometry analysis was performed at the RadBioPhys Laboratory (University of Pavia), obtaining cell percentages in each of the four phases in all studied conditions up to 72 hours post-irradiation.Cells show early G2-phase block (increasing in duration as dose increases) and later G1-phase accumulation. For each condition, we identified the best sets of model parameters that lead to a good agreement between model and experimental data, varying transition rates from G1- to S- and from G2- to M-phase.This work offers a proof-of-concept validation of the new computational tool, opening to its future development and, in perspective, to its integration in a wider framework for clinical use.Author summaryWe implemented a computational model able to describe how the progression in the cell cycle is perturbed when cells are exposed to ionizing radiation. It is known that radiation causes delays or arrest in cell cycle progression, and also that cells that are in different phases of the cycle at the time of exposure show different sensitivity to radiation. Chemotherapeutic drugs also affect cell cycle, and their action can be phase-specific. These findings can be exploited to find the optimal protocol of a combined radiotherapy/chemotherapy cancer treatment: to this aim, we need to know not only the effectiveness of an agent (dose/drug) in terms of cell killing, but also how surviving cells are distributed in the cell cycle. With the model we present, this information can be reproduced as a function of dose and time after radiation exposure. To test the model performance we measured distributions of cells in different phases of the cycle (using flow-cytometry) for human healthy fibroblast cells exposed to X-rays. The results of this work constitute a first step for further development of our model and its future integration in a tool for pre-clinical/clinical use.

scholarly journals METTL3-mediated M6a Modification Regulates Cell Cycle Progression of Dental Pulp Stem Cells

2021 ◽  
Author(s):  
Haiyun Luo ◽  
Wenjing Liu ◽  
Yanli Zhang ◽  
Xiao Jiang ◽  
Shiqing Wu ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Tissue Engineering ◽  
Stem Cells ◽  
Flow Cytometry ◽  
Differentially Expressed Genes ◽  
Dental Pulp ◽  
Cell Cycle Control ◽  
Dental Pulp Stem Cells ◽  
Differentially Expressed ◽  
Expression Level

Abstract Background: Dental pulp stem cells (DPSCs) exhibited self-renewal, pluripotency capacity and served as promising cells source in endodontic regeneration and tissue engineering. Meanwhile, the regenerative capacity of DPSCs is limited and reduced in long lifespan. N6-methyladenosine (m6A) is the most prevalent, reversible internal modification in RNAs. The methyltransferases complex and demethylases mediated m6A methylation and cooperated to impact various biological processes associated with stem cell fate determination. However, the biological effect of m6A methylation in DPSCs remained unclear. Methods: Cell surface markers and differentiation potential of primary DPSCs were identified and m6A immunoprecipitation with deep sequencing (m6A RIP-seq) was used to uncover characteristics of m6A modifications in DPSCs transcriptome. Expression level of m6A-related genes were evaluated in immature/mature pulp tissues and cells. Lentiviral vectors were constructed to knockdown or overexpress methyltransferase like 3 (METTL3). Cell morphology, viability, senescence and apoptosis were further analyzed by β-galactosidase, TUNEL staining and flow cytometry. Bioinformatic analysis combing m6A RIP and shMETTL3 RNA-seq was used to functionally enrich overlapped genes and screen target of METTL3. Cell cycle distributions were assayed by flow cytometry and m6A RIP-qPCR was used to confirm METTL3 mediated m6A methylation in DPSCs. Results: Here, m6A peaks distribution, binding area and motif in DPSCs were first revealed by m6A RIP-seq. We also found a relative high expression level of METTL3 in immature DPSCs with superior regenerative potential and METTL3 knockdown induced cell apoptosis and senescence. Furthermore, Conjoint analysis of m6A RIP and RNA-sequencing showed differentially expressed genes affected by METTL3 depletion was mainly enriched in cell cycle, mitosis and alteration of METTL3 expression resulted in cell cycle arrest which indicated METTL3 make essential effect in cell cycle control. To further investigate underlying mechanisms, we explored proteins interaction network of differentially expressed genes and Polo-like Kinase 1 (PLK1), a critical cycle modulator was identified as target of METTL3-mediated m6A methylation in DPSCs. Conclusions: These results revealed m6A methylated hallmarks in DPSCs and a regulatory role of METTL3 in cell cycle control. Our study shed light on therapeutic approaches in vital pulp therapy and serve new insight in stem cells based tissue engineering.

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