Coiled Body Heterogeneity Induced by G1 Arrest with Amiloride + Bumetanide

2002 ◽  
Vol 279 (1) ◽  
pp. 111-117 ◽  
Author(s):  
M Alliegro
Keyword(s):  
G1 Arrest ◽  
Coiled Body

Nuclear coiled bodies and the nucleolus

1994 ◽  
Vol 52 ◽  
pp. 20-21
Author(s):  
K. Brasch ◽  
J. Williams ◽  
D. Gallo ◽  
T. Lee ◽  
R. L. Ochs
Keyword(s):  
Mouse Liver ◽  
Nuclear Body ◽  
Nuclear Bodies ◽  
Model Systems ◽  
Coiled Body ◽  
Rrna Processing ◽  
Malignant Cells ◽  
Sm Proteins ◽  
Coiled Bodies ◽  
Unique Protein

Though first described in 1903 by Ramon-y-Cajal as silver-staining “accessory bodies” to nucleoli, nuclear bodies were subsequently rediscovered by electron microscopy about 30 years ago. Nuclear bodies are ubiquitous, but seem most abundant in hyperactive and malignant cells. The best studied type of nuclear body is the coiled body (CB), so termed due to characteristic morphology and content of a unique protein, p80-coilin (Fig.1). While no specific functions have as yet been assigned to CBs, they contain spliceosome snRNAs and proteins, and also the nucleolar protein fibrillarin. In addition, there is mounting evidence that CBs arise from or are generated near the nucleolus and then migrate into the nucleoplasm. This suggests that as yet undefined links may exist, between nucleolar pre-rRNA processing events and the spliceosome-associated Sm proteins in CBs.We are examining CB and nucleolar changes in three diverse model systems: (1) estrogen stimulated chick liver, (2) normal and neoplastic cells, and (3) polyploid mouse liver.

New Hybrid Scaffolds Based on Carbazole-Chalcones as Potent Anticancer Agents

2020 ◽  
Vol 20 ◽  
Author(s):  
Faisal Rashid ◽  
Sumera Zaib ◽  
Aliya Ibrar ◽  
Syeda Abida Ejaz ◽  
Aamer Saeed ◽  
...  
Keyword(s):  
Lactate Dehydrogenase ◽  
Hela Cells ◽  
Cervical Adenocarcinoma ◽  
G1 Arrest ◽  
Human Breast ◽  
Caspase 9 ◽  
Flow Cytometric ◽  
Pharmacodynamic Profile ◽  
Microscopic Studies ◽  
Mcf 7

Background and Objectives: Despite various technological advances for the treatment of cancer, the identification of new chemical entities with potent anticancer effects remain an indispensable requirement of the time due to multi-drug resistance exhibited by previously developed anticancer drugs. Particularly, the hybrid drugs incorporating two individual bioactive pharmacophores present medicinally important structural leads, thus improving the pharmacodynamic profile of the drug molecules. The antiproliferative and pro-apoptotic activity of the carbazole-chalcone hybrids on human breast and cervical cancer cells will be examined. Materials and Methods: To overcome such complications, in the current study, we evaluated the cytotoxic effects of carbazole-chalcone hybrids on human breast adenocarcinoma (MCF-7), cervical adenocarcinoma (HeLa) cells and normal cells i.e., baby hamster kidney cells (BHK-21) using MTT (dimethyl-2-thiazolyl-2,5-diphenyl-2H-tetrazolium bromide) assay. The mechanistic studies were performed on potent compound 4g by fluorescent microscopic studies, release of lactate dehydrogenase (LDH) and mitochondrial membrane potential, activation of caspase-9 and -3 and flow cytometric analysis. Results: As revealed by MTT assay, compound 4g was identified as the most potent derivative among the tested series with IC50 values of 5.64 and 29.15 μM against HeLa and MCF-7 cells, respectively. The results were compared with cisplatin. Fluorescent microscopic studies using 4′,6-diamidino-2-phenylindole (DAPI) and propidium iodide (PI) staining confirmed the occurrence of apoptosis in HeLa cells treated with the most active compound 4g. Moreover, compound 4g also triggered the release of lactate dehydrogenase (LDH) in treated HeLa and MCF-7 cells while a luminescence assay displayed a remarkable increase in the activity of caspase-9 and -3. Moreover, flow cytometric results revealed that compound 4g caused G0/G1 arrest in the treated HeLa cells. Conclusion: Our results demonstrated that the compound 4g possesses chemotherapeutic properties against breast cancer and cervical adenocarcinoma cells, thus warranting further research to test the anticancer efficacy of this compound at clinical level.

scholarly journals Repositioning Trimebutine Maleate as a Cancer Treatment Targeting Ovarian Cancer Stem Cells

Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 918
Author(s):  
Heejin Lee ◽  
Oh-Bin Kwon ◽  
Jae-Eon Lee ◽  
Yong-Hyun Jeon ◽  
Dong-Seok Lee ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Stem Cells ◽  
Drug Resistance ◽  
Cancer Stem Cells ◽  
Ovarian Cancer Cells ◽  
Therapeutic Drug ◽  
G1 Arrest ◽  
Dead Cell ◽  
Trimebutine Maleate ◽  
Simultaneous Inhibition

The overall five-year survival rate for late-stage patients of ovarian cancer is below 29% due to disease recurrence and drug resistance. Cancer stem cells (CSCs) are known as a major contributor to drug resistance and recurrence. Accordingly, therapies targeting ovarian CSCs are needed to overcome the limitations of present treatments. This study evaluated the effect of trimebutine maleate (TM) targeting ovarian CSCs, using A2780-SP cells acquired by a sphere culture of A2780 epithelial ovarian cancer cells. TM is indicated as a gastrointestinal motility modulator and is known to as a peripheral opioid receptor agonist and a blocker for various channels. The GI50 of TM was approximately 0.4 µM in A2780-SP cells but over 100 µM in A2780 cells, demonstrating CSCs specific growth inhibition. TM induced G0/G1 arrest and increased the AV+/PI+ dead cell population in the A2780-SP samples. Furthermore, TM treatment significantly reduced tumor growth in A2780-SP xenograft mice. Voltage gated calcium channels (VGCC) and calcium-activated potassium channels (BKCa) were overexpressed on ovarian CSCs and targeted by TM; inhibition of both channels reduced A2780-SP cells viability. TM reduced stemness-related protein expression; this tendency was reproduced by the simultaneous inhibition of VGCC and BKCa compared to single channel inhibition. In addition, TM suppressed the Wnt/β-catenin, Notch, and Hedgehog pathways which contribute to many CSCs characteristics. Specifically, further suppression of the Wnt/β-catenin pathway by simultaneous inhibition of BKCa and VGCC is necessary for the effective and selective action of TM. Taken together, TM is a potential therapeutic drug for preventing ovarian cancer recurrence and drug resistance.

scholarly journals Cytostatic Action of Novel Histone Deacetylase Inhibitors in Androgen Receptor-Null Prostate Cancer Cells

2021 ◽  
Vol 14 (2) ◽  
pp. 103
Author(s):  
Zohaib Rana ◽  
Joel D. A. Tyndall ◽  
Muhammad Hanif ◽  
Christian G. Hartinger ◽  
Rhonda J. Rosengren
Keyword(s):  
Prostate Cancer ◽  
Androgen Receptor ◽  
Cancer Cells ◽  
Hdac Inhibitors ◽  
G1 Arrest ◽  
Prostate Cancer Cells ◽  
Prostate Tumors ◽  
Normal Prostate ◽  
Pc3 Cells ◽  
Du145 Cells

Androgen receptor (AR)-null prostate tumors have been observed in 11–24% of patients. Histone deacetylases (HDACs) are overexpressed in prostate tumors. Therefore, HDAC inhibitors (Jazz90 and Jazz167) were examined in AR-null prostate cancer cell lines (PC3 and DU145). Both Jazz90 and Jazz167 inhibited the growth of PC3 and DU145 cells. Jazz90 and Jazz167 were more active in PC3 cells and DU145 cells in comparison to normal prostate cells (PNT1A) and showed a 2.45- and 1.30-fold selectivity and higher cytotoxicity toward DU145 cells, respectively. Jazz90 and Jazz167 reduced HDAC activity by ~60% at 50 nM in PC3 lysates. At 4 μM, Jazz90 and Jazz167 increased acetylation in PC3 cells by 6- to 8-fold. Flow cytometry studies on the cell phase distribution demonstrated that Jazz90 causes a G0/G1 arrest in AR-null cells, whereas Jazz167 leads to a G0/G1 arrest in DU145 cells. However, apoptosis only occurred at a maximum of 7% of the total cell population following compound treatments in PC3 and DU145 cells. There was a reduction in cyclin D1 and no significant changes in bcl-2 in DU145 and PC3 cells. Overall, the results showed that Jazz90 and Jazz167 function as cytostatic HDAC inhibitors in AR-null prostate cancer cells.

scholarly journals Slm9, a Novel Nuclear Protein Involved in Mitotic Control in Fission Yeast

Genetics ◽  
2000 ◽  
Vol 155 (2) ◽  
pp. 623-631
Author(s):  
Junko Kanoh ◽  
Paul Russell
Keyword(s):  
Cell Cycle ◽  
Fission Yeast ◽  
Cell Elongation ◽  
Nuclear Protein ◽  
G1 Arrest ◽  
Permissive Temperature ◽  
Cdc2 Kinase ◽  
Synthetic Lethal ◽  
Cycle Arrest ◽  
Novel Protein

Abstract In the fission yeast Schizosaccharomyces pombe, as in other eukaryotic cells, Cdc2/cyclin B complex is the key regulator of mitosis. Perhaps the most important regulation of Cdc2 is the inhibitory phosphorylation of tyrosine-15 that is catalyzed by Wee1 and Mik1. Cdc25 and Pyp3 phosphatases dephosphorylate tyrosine-15 and activate Cdc2. To isolate novel activators of Cdc2 kinase, we screened synthetic lethal mutants in a cdc25-22 background at the permissive temperature (25°). One of the genes, slm9, encodes a novel protein of 807 amino acids. Slm9 is most similar to Hir2, the histone gene regulator in budding yeast. Slm9 protein level is constant and Slm9 is localized to the nucleus throughout the cell cycle. The slm9 disruptant is delayed at the G2-M transition as indicated by cell elongation and analysis of DNA content. Inactivation of Wee1 fully suppressed the cell elongation phenotype caused by the slm9 mutation. The slm9 mutant is defective in recovery from G1 arrest after nitrogen starvation. The slm9 mutant is also UV sensitive, showing a defect in recovery from the cell cycle arrest after UV irradiation.

scholarly journals Discovery of vanoxerine dihydrochloride as a CDK2/4/6 triple-inhibitor for the treatment of human hepatocellular carcinoma

2021 ◽  
Vol 27 (1) ◽  
Author(s):  
Ying Zhu ◽  
Kun-Bin Ke ◽  
Zhong-Kun Xia ◽  
Hong-Jian Li ◽  
Rong Su ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Cycle Progression ◽  
G1 Arrest ◽  
Huh7 Cells ◽  
Synergistic Cytotoxicity ◽  
Combination Study ◽  
Experimental Approaches ◽  
Induced Apoptosis

Abstract Background Cyclin-dependent kinases 2/4/6 (CDK2/4/6) play critical roles in cell cycle progression, and their deregulations are hallmarks of hepatocellular carcinoma (HCC). Methods We used the combination of computational and experimental approaches to discover a CDK2/4/6 triple-inhibitor from FDA approved small-molecule drugs for the treatment of HCC. Results We identified vanoxerine dihydrochloride as a new CDK2/4/6 inhibitor, and a strong cytotoxicdrugin human HCC QGY7703 and Huh7 cells (IC50: 3.79 μM for QGY7703and 4.04 μM for Huh7 cells). In QGY7703 and Huh7 cells, vanoxerine dihydrochloride treatment caused G1-arrest, induced apoptosis, and reduced the expressions of CDK2/4/6, cyclin D/E, retinoblastoma protein (Rb), as well as the phosphorylation of CDK2/4/6 and Rb. Drug combination study indicated that vanoxerine dihydrochloride and 5-Fu produced synergistic cytotoxicity in vitro in Huh7 cells. Finally, in vivo study in BALB/C nude mice subcutaneously xenografted with Huh7 cells, vanoxerine dihydrochloride (40 mg/kg, i.p.) injection for 21 days produced significant anti-tumor activity (p < 0.05), which was comparable to that achieved by 5-Fu (10 mg/kg, i.p.), with the combination treatment resulted in synergistic effect. Immunohistochemistry staining of the tumor tissues also revealed significantly reduced expressions of Rb and CDK2/4/6in vanoxerinedihydrochloride treatment group. Conclusions The present study isthe first report identifying a new CDK2/4/6 triple inhibitor vanoxerine dihydrochloride, and demonstrated that this drug represents a novel therapeutic strategy for HCC treatment.

scholarly journals p53-dependent G1 arrest involves pRB-related proteins and is disrupted by the human papillomavirus 16 E7 oncoprotein.

1994 ◽  
Vol 91 (12) ◽  
pp. 5320-5324 ◽  
Author(s):  
R. J. Slebos ◽  
M. H. Lee ◽  
B. S. Plunkett ◽  
T. D. Kessis ◽  
B. O. Williams ◽  
...  
Keyword(s):  
Human Papillomavirus ◽  
G1 Arrest ◽  
Human Papillomavirus 16 ◽  
E7 Oncoprotein ◽  
Related Proteins
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