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Zhongguo Shi Yan Xue Ye Xue Za Zhi Apr 2009This study was purposed to investigate the biological effect of vinblastine (VLS), usually known as inductor of mitotic arrest, on MOLT-4 of ALL cells and to evaluate...
This study was purposed to investigate the biological effect of vinblastine (VLS), usually known as inductor of mitotic arrest, on MOLT-4 of ALL cells and to evaluate its significance. The cell arrest in M phase and/or cell apoptosis were induced by treatment of MOLT-4 cells with 0.05 microg/ml VLS for 0 - 12 hours; the DNA histogram was detected by flow cytometry; the morphological changes of cells were observed by confocal microscopy; the cell cycle distribution, cell apoptosis and morphological changes of cells before and after arrest were analyzed by using arrest increasing rate (AIR), arrest efficiency (AE), apoptosis rate (AR) and morphologic parameters respectively. The results indicated that the cell arrest did not accompanied by significant increase of apoptosis rate; the DNA histogram of cell arrest showed dynamic change of cell cycle in time-dependent manner; the arrest efficiency could be quantified. The cell arrest at M phase was accompanied by cell stack in S phase, the cell proliferation rate dropped after cell arrest occurred. The cells arrested at M phase possessed of characteristic morphologic features in cell mitosis. It is concluded that the vinblastine can solely induce arrest of MOLT-4 cells at M phase. This study provides experimental basis for further investigating the relation of cell cycle arrest to apoptosis, mechanism of checkpoint and development of new anticancer drugs.
Topics: Apoptosis; Cell Cycle; Cell Division; Flow Cytometry; Humans; Tumor Cells, Cultured; Vinblastine
PubMed: 19379566
DOI: No ID Found -
Molecular and Cellular Endocrinology Aug 2007Among the group of bioactive sphingolipids, sphingosylphosphorylcholine (SPC) has been known to induce both antiproliferative and proliferative effects depending on cell...
Among the group of bioactive sphingolipids, sphingosylphosphorylcholine (SPC) has been known to induce both antiproliferative and proliferative effects depending on cell type. In the present investigation we show that SPC (1-10 microM) reduced the proliferation of FRO cells (an anaplastic thyroid carcinoma cell line) in a concentration dependent manner. The effect was pertussis toxin insensitive, and independent of phospholipase C, protein kinase C, p38 kinase, or jun kinase. In addition to inhibiting the migration of FRO cells, application of SPC induced a rapid (<10 min) rounding of the cells, which was dependent on extracellular sodium. However, DAPI staining and caspase-3 analysis could not reveal any apoptotic effects of SPC. Furthermore, when cells treated with SPC for 24h were washed and replated, they continued to grow, albeit somewhat slower than control cells. Flow cytometry analysis revealed a significant increase in the population of cells in the G2-M phase, and a reduction in S phase. SPC reduced the phosphorylation of Akt with about 50% and evoked a substantial decrease in the amount of phosphorylated mitogen-activated protein (MAP) kinase. In cells treated with the PI3 kinase inhibitor wortmannin, both migration and proliferation were inhibited, as well as the amount of phosphorylated MAP kinase. Treatment of the cells with either SPC or wortmannin increased the levels of p21, but decreased that of cyclin B1 and Cdc2. Taken together, SPC is an effective suppressor of thyroid cancer cell proliferation and migration, and this effect is, in part, mediated by inhibition of both the PI3K-Akt and the MAP kinase signalling pathways.
Topics: Animals; Antineoplastic Agents; Cell Adhesion; Cell Division; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cell Shape; G2 Phase; Humans; Phosphatidylinositol 3-Kinases; Phosphorylcholine; Proto-Oncogene Proteins c-akt; Signal Transduction; Sphingosine; Thyroid Neoplasms
PubMed: 17606321
DOI: 10.1016/j.mce.2007.05.016 -
Biochemical and Biophysical Research... Oct 1994Flavonoids are pigments of edible plants. We have recently reported that most flavonoids induce G1 arrest in human cancer cells, and that genistein (an isoflavone)...
Flavonoids are pigments of edible plants. We have recently reported that most flavonoids induce G1 arrest in human cancer cells, and that genistein (an isoflavone) specifically inhibits their cell cycle at G2-M phase. In the present study, apigenin (a flavone) was found to inhibit the proliferation of B104 rat neuronal cells, and flow-cytometric analysis showed that apigenin arrested their cell cycle at G2-M phase. This effect was dose-dependent and reversible when apigenin was removed from the culture medium. Microscopic observation showed that apigenin did not significantly increase the mitotic index compared with the control. Further, apigenin induced morphological differentiation, that is, elongation and arborization of neurites in B104 cells. This is the first report to show that apigenin inhibited the proliferation of malignant tumor cells by G2-M arrest and induced morphological differentiation.
Topics: Animals; Cell Differentiation; Cell Division; Cell Line; Chamomile; Flavonoids; G2 Phase; Mitosis; Mitotic Index; Neurons; Oils, Volatile; Plants, Medicinal; Rats
PubMed: 7980517
DOI: 10.1006/bbrc.1994.2498 -
Clinical Science (London, England :... Feb 1995
Review
Topics: Biomarkers; Cell Count; Cell Division; Cells; Cytological Techniques; Flow Cytometry; Humans; Mitosis; S Phase
PubMed: 7720335
DOI: 10.1042/cs0880119 -
Nature Oct 1960
Topics: Cell Division; Mitosis; Neurospora
PubMed: 13724138
DOI: 10.1038/188338a0 -
The Journal of Pharmacology and... Nov 2001Proliferation and maturation of neurons has been demonstrated to occur at a significant rate in discrete regions of adult brain, including the hippocampus and... (Review)
Review
Proliferation and maturation of neurons has been demonstrated to occur at a significant rate in discrete regions of adult brain, including the hippocampus and subventricular zone. Moreover, adult neurogenesis is an extremely dynamic process that is regulated in both a positive and negative manner by neuronal activity and environmental factors. It has been suggested to play a role in several important neuronal functions, including learning, memory, and response to novelty. In addition, exposure to psychotropic drugs or stress regulates the rate of neurogenesis in adult brain, suggesting a possible role for neurogenesis in the pathophysiology and treatment of neurobiological illnesses such as depression, post-traumatic stress disorder, and drug abuse. As the mechanisms that control adult neurogenesis continue to be identified, the exciting prospect of developing pharmacological agents that specifically regulate the proliferation and maturation of neurons in the adult brain could be fulfilled.
Topics: Adult; Animals; Cell Division; Humans; Mitosis; Neurons; Psychotropic Drugs; Stress, Physiological
PubMed: 11602648
DOI: No ID Found -
The Journal of Eukaryotic Microbiology Jan 2018The flagellated protist Tritrichomonas foetus is a parasite that causes bovine trichomonosis, a major sexually transmitted disease in cattle. Cell division has been...
The flagellated protist Tritrichomonas foetus is a parasite that causes bovine trichomonosis, a major sexually transmitted disease in cattle. Cell division has been described as a key player in controlling cell survival in other cells, including parasites but there is no information on the regulation of this process in T. foetus. The regulation of cytokinetic abscission, the final stage of cell division, is mediated by members of the ESCRT (endosomal sorting complex required for transport) machinery. VPS32 is a subunit within the ESCRTIII complex and here, we report that TfVPS32 is localized on cytoplasmic vesicles and a redistribution of the protein to the midbody is observed during the cellular division. In concordance with its localization, deletion of TfVPS32 C-terminal alpha helices (α5 helix and/or α4-5 helix) leads to abnormal T. foetus growth, an increase in the percentage of multinucleated parasites and cell cycle arrest at G2/M phase. Together, these results indicate a role of this protein in controlling normal cell division.
Topics: Cell Division; Cytokinesis; Protozoan Proteins; Tritrichomonas foetus
PubMed: 28477402
DOI: 10.1111/jeu.12424 -
FASEB Journal : Official Publication of... Nov 1994A few years after the identification of cyclin B-cdc2 kinase as the universal factor that controls onset of M-phase in eukaryotic cells, MPF (M-phase promoting factor),... (Review)
Review
A few years after the identification of cyclin B-cdc2 kinase as the universal factor that controls onset of M-phase in eukaryotic cells, MPF (M-phase promoting factor), it became evident that all transitions of the cell cycle are controlled through phosphorylation of specific targets due to changes in the activity of a variety of cyclin-dependent kinases (cdks). These transitions include conversion of quiescent cells to a state of active proliferation, commitment to DNA replication, initiation of DNA replication, and entry into and exit from mitosis. Changes in the activity of cdks along the cell cycle depend not only on their association with a variety of cyclins (including G1/S and G2/M cyclins) and on posttranslational modifications by phosphorylation-dephosphorylation reactions, but also on specific protein inhibitors and on protein degradation.
Topics: Animals; Cell Division; Cyclin-Dependent Kinases; DNA Replication; Humans; Mitosis
PubMed: 7958616
DOI: 10.1096/fasebj.8.14.7958616 -
Cell cycle-dependent Cu uptake explained the heterogenous responses of Chlamydomonas to Cu exposure.Environmental Pollution (Barking, Essex... Feb 2023Growing evidence suggested that microorganisms exhibited heterogeneous sensitivity to toxicants, but their underlying mechanisms remain largely unknown. The asynchronous...
Growing evidence suggested that microorganisms exhibited heterogeneous sensitivity to toxicants, but their underlying mechanisms remain largely unknown. The asynchronous cell cycle progression in natural population implies the connection between cell cycle and heterogeneity. Here, the heterogenous responses of Chlamydomonas reinhardtii upon Cu stress were confirmed with the aid of a fluorometric probe for imaging Cu(I), implying the connection with cell cycle. Our results further indicated that the increase of labile Cu(I) was related to the cell division, leading to the fluctuation of labile Cu(I) with diurnal cycle and cell cycle, respectively. However, lack of Cu mainly influenced the cell division. We demonstrated that G2/M phase was the critical stage requiring high Cu quota during cell division. Specifically, algae at G2/M phase required 10-fold of Cu quota compared with that at G1 phase, which was related to the mitochondrial replication. Eventually, the heterogeneous Cu uptake ability of algae at different cell phases led to the heterogeneous responses to Cu exposure. Overall, Cu could influence the cell cycle through mediating the cell division, and in turn algae at different cell phases exhibited different Cu sensitivities. This study firstly uncovered the underlying mechanisms of heterogeneous Cu sensitivity for phytoplankton, which could help to evaluate the potential ecological risks of Cu.
Topics: Chlamydomonas; Cell Cycle; Cell Division; Biological Transport; Chlamydomonas reinhardtii
PubMed: 36608730
DOI: 10.1016/j.envpol.2023.121013 -
Cancer Letters Dec 2004The cytotoxic mechanism of protein-bound polysaccharide isolated from Phellinus linteus (PL, Mesima) has been investigated. PL inhibited the proliferation and colony...
The cytotoxic mechanism of protein-bound polysaccharide isolated from Phellinus linteus (PL, Mesima) has been investigated. PL inhibited the proliferation and colony formation of SW480 human colon cancer cells. Flow cytometry analysis showed that PL increased the populations of both apoptotic sub-G1 and G2/M phase. The result obtained from TUNEL assay corroborated apoptosis which was shown in flow cytometry. Western blot analysis suggested that PL-induced apoptosis and growth inhibition were associated with decrease in Bcl-2, increase of the release of cytochrome c, and reduced expression of cyclin B1. These results suggest that PL has a direct antitumor effect through apoptosis and cell cycle blockade in certain cancer cells.
Topics: Antineoplastic Agents; Apoptosis; Basidiomycota; Cell Cycle; Cell Division; Cell Line, Tumor; Cell Proliferation; G2 Phase; Humans; Immunologic Factors; Polysaccharides
PubMed: 15533593
DOI: 10.1016/j.canlet.2004.07.014