scholarly journals G1 Cell Cycle Arrest and Extrinsic Apoptotic Mechanisms Underlying the Anti-Leukemic Activity of CDK7 Inhibitor BS-181

Cancers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3845
Author(s):  
Shin Young Park ◽  
Ki Yun Kim ◽  
Do Youn Jun ◽  
Su-Kyeong Hwang ◽  
Young Ho Kim
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Jurkat Cells ◽  
Parp Cleavage ◽  
Caspase 8 ◽  
Down Regulation ◽  
Blocking Antibody ◽  
Cycle Arrest ◽  
G1 Cell Cycle Arrest ◽  
Induced Apoptosis

In vitro antitumor activity of the CDK7 inhibitor BS-181 against human T-ALL Jurkat cells was determined. Treatment of Jurkat clones (JT/Neo) with BS-181 caused cytotoxicity and several apoptotic events, including TRAIL/DR4/DR5 upregulation, c-FLIP down-regulation, BID cleavage, BAK activation, ΔΨm loss, caspase-8/9/3 activation, and PARP cleavage. However, the BCL-2-overexpressing Jurkat clone (JT/BCL-2) abrogated these apoptotic responses. CDK7 catalyzed the activating phosphorylation of CDK1 (Thr161) and CDK2 (Thr160), and CDK-directed retinoblastoma phosphorylation was attenuated in both BS-181-treated Jurkat clones, whereas only JT/BCL-2 cells exhibited G1 cell cycle arrest. The G1-blocker hydroxyurea augmented BS-181-induced apoptosis by enhancing TRAIL/DR4/DR5 upregulation and c-FLIP down-regulation. BS-181-induced FITC–annexin V-positive apoptotic cells were mostly in the sub-G1 and G1 phases. BS-181-induced cytotoxicity and mitochondrial apoptotic events (BAK activation/ΔΨm loss/caspase-9 activation) in Jurkat clones I2.1 (FADD-deficient) and I9.2 (caspase-8-deficient) were significantly lower than in A3 (wild-type). Exogenously added recombinant TRAIL (rTRAIL) markedly synergized BS-181-induced apoptosis in A3 cells but not in normal peripheral T cells. The cotreatment cytotoxicity was significantly reduced by the DR5-blocking antibody but not by the DR4-blocking antibody. These results demonstrated that the BS-181 anti-leukemic activity is attributed to extrinsic TRAIL/DR5-dependent apoptosis preferentially induced in G1-arrested cells, and that BS-181 and rTRAIL in combination may hold promise for T-ALL treatment.

The Bioactive Polyphenol Curcumin (diferuloylmethane) In Human Apolipoprotein A-1 Nanodisks Enhances Apoptosis and G1 Cell Cycle Arrest In Mantle Cell Lymphoma Compared with Free Curcumin

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3934-3934
Author(s):  
Amareshwar T.K. Singh ◽  
Mistuni Ghosh ◽  
C. Shad Thaxton ◽  
Trudy M. Forte ◽  
Robert O. Ryan ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Drug Delivery ◽  
Cyclin D1 ◽  
Cell Cycle Arrest ◽  
Cell Lines ◽  
Cell Lymphoma ◽  
Parp Cleavage ◽  
Cycle Arrest ◽  
Mantle Cell ◽  
Induced Apoptosis

Abstract Abstract 3934 Background: Mantle cell lymphoma (MCL) is a pre–germinal center neoplasm characterized by cyclin D1 overexpression resulting from translocation of the cyclin D1 gene on 11q13 to the promoter of the immunoglobulin heavy chain locus on 14q32. Since MCL is incurable with standard lymphoma therapies, new treatment approaches are needed that target specific biologic pathways. The bioactive polyphenol curcumin (Curc), derived from the rhizome of Curcuma longa Linn, has been shown to have pleiotropic activities related to its complex chemistry and its influence on multiple signaling pathways including NF-kB, Akt, Nrf2 and pathways involved in metastasis and angiogenesis. Curc has been shown to cause growth arrest and apoptosis of BKS-2 immature B-cell lymphoma by downregulating growth and survival promoting genes (Clin Immunol 1999; 93:152). However, because of poor aqueous solubility Curc has had limited clinical utility, so investigators have explored nanoparticle drug delivery approaches (J Nanobiotech 2007, 5:3, MCT 2010; 9:2255). We reasoned that effective and targeted drug delivery by nanoparticles required appropriate receptors to facilitate binding. We therefore screened lymphoma cell lines for receptors that recognize apolipoprotein (apo) A-1. We hypothesized that a novel discoidal nanoparticle (ND) consisting of apoA-1, phospholipid and Curc (Curc ND) would bind to such receptors to facilitate drug delivery. Methods: We compared biologic activity of free Curc vs. Curc-ND in MCL cell lines expressing receptors for apoA-1. Cell lines were grown and maintained in culture, treated, and apoptosis and cell cycle progression was measured by flow cytometry. Relevant signaling intermediates and presence of apoA-1 receptors were measured by immunoblotting using specific antibodies. Results: Granta and Jeko cells (both MCL cell lines) expressed apoA-1 receptors including class B scavenger receptor (SR-B1) and the ATP-binding cassette transporter of the sub-family G1 (ABCG1). To compare the pro-apoptotic effect of free Curc and Curc-ND, Granta cells were incubated with free Curc, Curc-ND, empty ND, and medium alone (untreated). Compared to medium alone, empty ND had no effect while free Curc (20 μM) induced apoptosis. Curc-ND produced a dose-dependent increase in apoptosis, with ∼70% apoptosis at 20 μM. To investigate the mechanism of Curc-ND induced apoptosis, apoptosis-related proteins were studied in cultured Granta cells. A time-dependent decrease in caspase-9 levels was observed following incubation with Curc-ND or free Curc. The decrease in caspase-9 seen with Curc-ND, however, occurs much earlier (between 2–4 h of incubation) than for free-Curc. Caspase-3 was undetectable after 16 h with either treatment. Loss of this band implies activation of caspase-3, which was confirmed by PARP cleavage, wherein a decrease in the 116 kD band was accompanied by an increase in the 85 kD cleavage product. Unlike free Curc, Curc-ND induced PARP cleavage even at 16 h of incubation, suggesting sustained drug release. Curc-ND downregulated cyclin D1, decreased Akt phosphorylation and enhanced cleavage of caspases-9 and -3, and PARP. In addition, Curc-ND induced G1 cell cycle arrest to a greater extent than free Curc in Granta and Jeko cells (Granta: Control 34% G1, Curc 37% G1, Curc-ND 46% G1; Jeko: Control 39% G1, Curc 49% G1, Curc-ND 54% G1). Conclusion: We have shown that the MCL cell lines Granta and Jeko express apoA-1 receptors, making them likely targets for discoidal nanoscale delivery vehicles stabilized with Apo-A1. These nanodisks, when carrying the polyphenol Curc, can result in increased caspase -dependent apoptosis, cell cycle arrest, downregulation of cyclin-D1 and decreased p-Akt. These data suggest that the pleiotropic polyphenol Curc has cell killing/arrest activity in MCL and that Curc-ND may be a potential therapeutic with drug targeting ability. Disclosures: Forte: Lypro Biosciences: Employment.

scholarly journals Effects of annexin A1 on apoptosis and cell cycle arrest in human leukemic cell lines

2019 ◽  
Vol 69 (1) ◽  
pp. 75-86 ◽  
Author(s):  
Affidah Sabran ◽  
Endang Kumolosasi ◽  
Ibrahim Jantan
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Leukemic Cell ◽  
Jurkat Cells ◽  
G1 Phase ◽  
U937 Cells ◽  
Annexin A1 ◽  
Leukemic Cell Lines ◽  
Cycle Arrest ◽  
Induced Apoptosis

Abstract Recent studies suggest that annexin A1 (ANXA1) promotes apoptosis in cancerous cells. This study aims to investigate the effects of ANXA1 on apoptosis and cell cycle arrest in K562, Jurkat and U937 cells and peripheral blood mononu-clear cells (PBMC). Cells were treated with ANXA1 and cyclophosphamide prior to flow cytometry analysis for apoptosis and cell cycle arrest induction. At 2.5µM, ANXA1 induced significant apoptosis in K562 (p ≤ 0.001) and U937 (p ≤ 0.05) cells, with EC50 values of 3.6 and 3.8 µM, respectively. In Jurkat cells, induction was not significant (EC50, 17.0 µM). No significant apoptosis induction was observed in PBMC. ANXA1 caused cycle arrest in the G0/G1 phase in K562 and U937 cells with p ≤ 0.001 for both, and (p ≤ 0.01) for Jurkat cells. ANXA1 induced apoptosis and cycle arrest in the G0/G1 phase in K562 and U937 cells, causing only cell cycle arrest in Jurkat cells.

Induction of cell cycle arrest and apoptosis by BCG infection in cultured human bronchial airway epithelial cells

2007 ◽  
Vol 293 (2) ◽  
pp. L393-L401 ◽  
Author(s):  
Yi-Mu Lai ◽  
Kamal A. Mohammed ◽  
Najmunnisa Nasreen ◽  
Aidos Baumuratov ◽  
Brendan F. Bellew ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Caspase 3 ◽  
Airway Epithelial Cells ◽  
Caspase 8 ◽  
Airway Epithelial ◽  
Cycle Arrest ◽  
Fas L ◽  
Induced Apoptosis ◽  
Partial Blockade

Bronchial airway epithelial cells (BAEpC) are among the first cells to encounter M. tuberculosis following airborne infection. However, the response of BAEpC to M. tuberculosis infection has been little studied. This study investigates the response of a human BAEpC cell line (BEAS-2B) to infection with Mycobacterium bovis Bacille Calmette Guerin (BCG). Cultured human BEAS-2B cells were experimentally infected with BCG. Uninfected BEAS-2B cultures were included as controls. Following infection, BEAS-2B cells were evaluated by various methods at various time points up to 3 days. Cell proliferation was evaluated by cellular bioreduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Distribution of cells along the cell cycle was evaluated by FACS analysis of cellular DNA. Apoptotic cells were identified by cell death ELISA and the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling method. Eighty-four apoptosis-relevant genes were screened by PCR gene microarray. Translation of Fas, Fas ligand (Fas-L), and Fas-associated death domain (FADD) were evaluated quantitatively by real-time PCR. Expression of Fas and FADD proteins was evaluated by immunofluorescence and Western blot. Activity of caspase-3 and caspase-8 was evaluated by colorimetric assay of their enzymatic activity. BCG infection of BEAS-2B cells inhibits proliferation, induces cell cycle arrest at the G0/G1phase, causes apoptosis, modulates transcription of multiple apoptosis-relevant genes, promotes translation of Fas, Fas-L, and FADD, upregulates expression of Fas and FADD proteins, and increases activity of caspase-3 and caspase-8. Infection with BCG does not cause any significant change in the secretion of TGF-β. The roles of Fas and FADD as mediators of BCG-induced apoptosis in BEAS-2B cells were tested by partial blockade of Fas and FADD expression with silencing RNA. Partial blockade of Fas or FADD expression results in a decreased apoptotic response to BCG infection. In conclusion, BCG induces cell cycle arrest and apoptosis in BEAS-2B cells. BCG induced apoptosis of BEAS-2B cells via the Fas death receptor pathway.

Inhibition of ultraviolet B (UVB) induced apoptosis in A431 cells by mimosine is not dependent on cell cycle arrest

2002 ◽  
Vol 80 (7) ◽  
pp. 650-653
Author(s):  
D O Cliche ◽  
S Girouard ◽  
N Bissonnette ◽  
D J Hunting
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Rna Polymerase Ii ◽  
Ultraviolet B ◽  
Caspase Activation ◽  
A431 Cells ◽  
Cycle Arrest ◽  
Activation Assay ◽  
G1 Cell Cycle Arrest ◽  
Induced Apoptosis

Ultraviolet (UV) radiation is a strong apoptotic trigger in many cell types. We have previously reported that a plant amino acid, mimosine (beta-[N-(3-hydroxy-4-pyridone)]-alpha-aminopropionic acid), with a well-known reversible G1 cell cycle arrest activity can inhibit apoptosis induced by UV irradiation and RNA polymerase II blockage in human A431 cells. Here, apoptosis was measured with a fluorimetric caspase activation assay. Interestingly, the protective state was effective up to 24 h following removal of mimosine from the culture medium while cells were progressing in the cell cycle. Our results demonstrate that the protective effect of mimosine against UV-induced apoptosis can be dissociated from its G1 cell-cycle arrest activity.Key words: mimosine, apoptosis, cell cycle, A431 cells, caspase activation assay.

scholarly journals The pseudo-caspase FLIP(L) regulates cell fate following p53 activation

2020 ◽  
Vol 117 (30) ◽  
pp. 17808-17819 ◽  
Author(s):  
Andrea Lees ◽  
Alexander J. McIntyre ◽  
Nyree T. Crawford ◽  
Fiammetta Falcone ◽  
Christopher McCann ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Cell Fate ◽  
Target Genes ◽  
Caspase 8 ◽  
Cycle Arrest ◽  
P53 Activation ◽  
Induced Apoptosis

p53 is the most frequently mutated, well-studied tumor-suppressor gene, yet the molecular basis of the switch from p53-induced cell-cycle arrest to apoptosis remains poorly understood. Using a combination of transcriptomics and functional genomics, we unexpectedly identified a nodal role for the caspase-8 paralog and only human pseudo-caspase, FLIP(L), in regulating this switch. Moreover, we identify FLIP(L) as a direct p53 transcriptional target gene that is rapidly up-regulated in response to Nutlin-3A, an MDM2 inhibitor that potently activates p53. Genetically or pharmacologically inhibiting expression of FLIP(L) using siRNA or entinostat (a clinically relevant class-I HDAC inhibitor) efficiently promoted apoptosis in colorectal cancer cells in response to Nutlin-3A, which otherwise predominantly induced cell-cycle arrest. Enhanced apoptosis was also observed when entinostat was combined with clinically relevant, p53-activating chemotherapy in vitro, and this translated into enhanced in vivo efficacy. Mechanistically, FLIP(L) inhibited p53-induced apoptosis by blocking activation of caspase-8 by the TRAIL-R2/DR5 death receptor; notably, this activation was not dependent on receptor engagement by its ligand, TRAIL. In the absence of caspase-8, another of its paralogs, caspase-10 (also transcriptionally up-regulated by p53), induced apoptosis in Nutlin-3A-treated, FLIP(L)-depleted cells, albeit to a lesser extent than in caspase-8-proficient cells. FLIP(L) depletion also modulated transcription of canonical p53 target genes, suppressing p53-induced expression of the cell-cycle regulator p21 and enhancing p53-induced up-regulation of proapoptotic PUMA. Thus, even in the absence of caspase-8/10, FLIP(L) silencing promoted p53-induced apoptosis by enhancing PUMA expression. Thus, we report unexpected, therapeutically relevant roles for FLIP(L) in determining cell fate following p53 activation.

scholarly journals Loss of p21 disrupts p14ARF-induced G1 cell cycle arrest but augments p14ARF-induced apoptosis in human carcinoma cells

Oncogene ◽  
2005 ◽  
Vol 24 (25) ◽  
pp. 4114-4128 ◽  
Author(s):  
Philipp G Hemmati ◽  
Guillaume Normand ◽  
Berlinda Verdoodt ◽  
Clarissa von Haefen ◽  
Anne Hasenjäger ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Carcinoma Cells ◽  
Human Carcinoma ◽  
Cycle Arrest ◽  
G1 Cell Cycle Arrest ◽  
Induced Apoptosis

Anticancer efficacy of natural withanolides in triple-negative breast cancer through down regulation of BRCA1, cell-cycle arrest, and induction of apoptosis.

2011 ◽  
Vol 29 (27_suppl) ◽  
pp. 291-291
Author(s):  
X. Zhang ◽  
A. K. Samadi ◽  
R. Mukerji ◽  
B. N. Timmermann ◽  
M. S. Cohen
Keyword(s):  
Breast Cancer ◽  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Triple Negative Breast Cancer ◽  
Triple Negative ◽  
Down Regulation ◽  
Brca1 Protein ◽  
Protein Levels ◽  
Cycle Arrest ◽  
Induced Apoptosis

291 Background: Triple negative breast cancer is often chemoresistant creating the need for novel improved drugs for this disease. Naturally derived withanolides such as withaferin A (WA) have shown potent preclinical efficacy in breast cancers. The purpose of this study is to better define the anticancer activity of WA and novel analogs(X001 and X003) containing a 19-OH substitution, in triple negative MDA-MB-231cells where BRCA1 is important for cell survival. Methods: Cells were treated with increasing doses of WA, X001, or X003 for 24 h. MTS and trypan blue exclusion assays were used to examine cell proliferation and viability. Cell cycle was examined using propidium iodide (PI) staining on flow cytometry (FC). Annexin-V/PI co-staining on FC was used to detect apoptosis. Western analysis was used to evaluate BRCA1 protein levels as well as to confirm apoptosis by PARP cleavage and caspase-3 activation. Results: X003, WA, and X001 inhibited MDA-MB-231 cell viability (IC50=125, 500 and 1300nM respectively). IC50 level of WA induced G2/M phase cell cycle arrest while 2.5μM also induced apoptosis at 24 h as well as a significant decrease in both total and phospho-Akt protein levels. In addition, WA decreased BRCA1, heat shock factor 1, and mutant p53 protein levels in a dose-dependent manner. 2.5 μM of WA decreased BRCA1 protein levels by 75% compared to controls at 24 h (p<0.01) while its natural analogs X003 and X001 induced apoptosis associated with BRCA1 down-regulation at 200nM (1.5xIC50) and 6.5μM (5xIC50) and a G2/M cell cycle arrest at only 50nM (50%IC50) and 2μM (1.5xIC50) respectively after 24 hours. Conclusions: Natural withanolides such as WA and its potent analog X003 demonstrate anticancer effects on triple negative breast cancer cells through cell cycle arrest, apoptosis and down-regulation of BRCA1 protein expression. Targeting BRCA1 in triple negative breast cancer with natural withanolides represents a novel approach for future translational studies in this difficult disease.

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