p53 Prevents Immature Escaping from Cell Cycle G2 Checkpoint Arrest through Inhibiting cdk2-dependent NF-Y Phosphorylation

Un-Jung Yun,박희동,신득용 대한암학회 2006 Cancer Research and Treatment Vol.38 No.4

Recent studies have suggested that p53 regulates the G2 checkpoint in the cell cycle and this function is required for the maintenance of genomic integrity. In this study, we addressed a role of p53 in escaping from cell cycle G2 arrest following DNA damage.Materials and Methods: Cell cycle checkpoint arrest in the human colon cancer cell line HCT116 and its derivatives carry p53 or p21 deletions, were examined by FACS analysis, immunoprecipitation, Western blot and IP-kinase assay.Results: While the cells with functional p53 were arrested at both the G1 and G2 checkpoints, the p53-deficient cells failed to arrest at G1, but they were arrested at G2. However, the p53-deficient cells failed to sustain G2 checkpoint arrest and they entered mitosis earlier than did the p53-positive cells and so this resulted in extensive cell death. Cdc2 kinase becomes reactivated in p53-deficient cells in association with entry into mitosis, but not in the p53-positive cells. Upon DNA damage, the p21-deficient cells, like the p53-negative cells, not only failed to repress cdk2- dependent NF-Y phosphorylation, but they also failed to repress the expression of such cell cycle G2-regulatory genes as cdc2, cyclin B, RNR-R2 and cdc25C, which have all been previously reported as targets of NF-Y transcription factor.Conclusion: p53 is essential to prevent immature escaping from cell cycle G2 checkpoint arrest through p21-mediated cdk2 inactivation, and this leads to inhibition of cdk2-dependent NF-Y phosphorylation and NF-Y dependent transcription of the cell cycle G2-rgulatory genes, including cdc2 and cyclin B. (Cancer Res Treat. 2006;38:224-228)

Cadmium Induces Cell Cycle Arrest and Change in Expression of Cell Cycle Related Proteins in Breast Cancer Cell Lines

Lee Young Joo,Kang Tae Seok,Kim Tae Sung,Moon Hyun Ju,Kang Il Hyun,Oh Ji Young,Kwon Hoonjeong,Han Soon Young Korean Society of ToxicologyKorea Environmental Mu 2005 Toxicological Research Vol.21 No.1

Cadmium is an environmental pollutant exposed from contaminated foods or cigarette smoking and known to cause oxidative damage in organs. We investigated the cadmium-induced apoptosis and cell arrest in human breast cancer cells, MCF-7 cells and MDA-MB-231 cells. Obvious apoptotic cell death was shown in CdCl₂ 100 μM treatment for 12 hr, which were determined by DAPI staining and flow cytometric analysis. In cell cycle analysis, MCF-7 cells and MDA-MB-231 cells were arrested in S phase and G2/M phase respectively. These could be explained by the induction of cell cycle inhibitory protein, p21/sup Waf1/Cip1/ and p27/sup Kip1/, expression and reduction of cyclin/Cdk complexes in both cell lines. The decreased expression of cyclin A and Cdk2 in MCF-7 cells and cyclin B1 and Cdc2 in MDA-MB-231 cells were consistent with the flow cytometric observation. p-ERK expression was increased dose-dependent manner in both cell lines. It suggests that ERK MAPK pathway are involved in cadmium-induced cell cycle arrest and apoptosis. Moreover, cotreatment of zinc (100 μM, 12 hr) recovered the cadmium-induced cell arrest in both cells, which shows cadmium-induced oxidative stress mediates apoptosis and cell cycle arrest in human breast cancer cells.

Detection of Mitotic Centromere-Associated Kinesin (MCAK) During Cell- Cycle Progression of Human Jurkat T Cells Using Polyclonal Antibody Raised Against Its N-Terminal Region Overexpressed in E. coli

( Do Youn Jun ),( Seok Woo Rue ),( Byung Woo Kim ),( Young Ho Kim ) 한국미생물생명공학회 2003 Journal of microbiology and biotechnology Vol.13 No.6

Ankyrin Repeat-Rich Membrane Spanning (ARMS)/Kidins220 Scaffold Protein Regulates Neuroblastoma Cell Proliferation through p21

Jung, Heekyung,Shin, Joo-Hyun,Park, Young-Seok,Chang, Mi-Sook Korean Society for Molecular and Cellular Biology 2014 Molecules and cells Vol.37 No.12

Cell proliferation is tightly controlled by the cell-cycle regulatory proteins, primarily by cyclins and cyclin-dependent kinases (CDKs) in the $G_1$ phase. The ankyrin repeat-rich membrane spanning (ARMS) scaffold protein, also known as kinase D-interacting substrate of 220 kDa (Kidins 220), has been previously identified as a prominent downstream target of neurotrophin and ephrin receptors. Many studies have reported that ARMS/Kidins220 acts as a major signaling platform in organizing the signaling complex to regulate various cellular responses in the nervous and vascular systems. However, the role of ARMS/Kidins220 in cell proliferation and cell-cycle progression has never been investigated. Here we report that knockdown of ARMS/Kidins220 inhibits mouse neuroblastoma cell proliferation by inducing slowdown of cell cycle in the $G_1$ phase. This effect is mediated by the upregulation of a CDK inhibitor p21, which causes the decrease in cyclin D1 and CDK4 protein levels and subsequent reduction of pRb hyperphosphorylation. Our results suggest a new role of ARMS/Kidins220 as a signaling platform to regulate tumor cell proliferation in response to the extracellular stimuli.

Induction of Cell Cycle Arrest, Apoptosis, and Reducing the Expression of MCM Proteins in Human Lung Carcinoma A549 Cells by Cedrol, Isolated from Juniperus chinensis

Yun Hee Jung,Jeoung Da Jeoung,Jin Soojung,Park Jung-ha,Lee Eun-Woo,Lee Hyun-Tai,Choi Yung Hyun,Kim Byung Woo,Kwon Hyun Ju 한국미생물·생명공학회 2022 Journal of microbiology and biotechnology Vol.32 No.7

Proteins related to DNA replication have been proposed as cancer biomarkers and targets for anticancer agents. Among them, minichromosome maintenance (MCM) proteins, often overexpressed in various cancer cells, are recognized both as notable biomarkers for cancer diagnosis and as targets for cancer treatment. Here, we investigated the activity of cedrol, a single compound isolated from Juniperus chinensis, in reducing the expression of MCM proteins in human lung carcinoma A549 cells. Remarkably, cedrol also strongly inhibited the expression of all other MCM protein family members in A549 cells. Moreover, cedrol treatment reduced cell viability in A549 cells, accompanied by cell cycle arrest at the G1 phase, and enhanced apoptosis. Taken together, this study broadens our understanding of how cedrol executes its anticancer activity while demonstrating that cedrol has potential application in the treatment of human lung cancer as an inhibitor of MCM proteins.

Cell-Cycle Checkpoints in a State Network

J. S. Lee,강병남,E. Oh 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.-

The sequence of cell-cycle activities can be seen as a dynamic flow in a state space (SS) that is composed of the Boolean states. Here, we propose a mathematical method to identify the checkpoint proteins through topological features of the network defined in SS. The checkpoint provides a cell with recovery time by arresting the cell-cycle process when any abnormal problem arises in the cell cycle. Therefore, the checkpoint proteins become active when the cell cycle has malfunctioned, whereas they remain inactive otherwise. Proceeding from this fact, we identify the checkpoint proteins by measuring the basin size of each node in SS and summing over the nodes in SS in which a specific protein is ON or OFF, respectively. The difference of these quantities in the ON or OFF state of a specific protein becomes extreme when the specific protein is associated with the checkpoint protein. This mathematical result indicates that indeed the checkpoints play the role of repairing machinery in the cell cycle.

ATM Signaling Pathway Is Implicated in the SMYD3-mediated Proliferation and Migration of Gastric Cancer Cells

Lei Wang,Qiu-Tong Wang,Yu-Peng Liu,Qing-Qing Dong,Hai-Jie Hu,Zhi Miao,Shuang Li,Yong Liu,Hao Zhou,Tong-Cun Zhang,Wen-Jian Ma,Xuegang Luo 대한위암학회 2017 Journal of gastric cancer Vol.17 No.4

Purpose: We previously found that the histone methyltransferase suppressor of variegation, enhancer of zeste, trithorax and myeloid-nervy-deformed epidermal autoregulatory factor-1 domain-containing protein 3 (SMYD3) is a potential independent predictive factor or prognostic factor for overall survival in gastric cancer patients, but its roles seem to differ from those in other cancers. Therefore, in this study, the detailed functions of SMYD3 in cell proliferation and migration in gastric cancer were examined. Materials and Methods: SMYD3 was overexpressed or suppressed by transfection with an expression plasmid or siRNA, and a wound healing migration assay and Transwell assay were performed to detect the migration and invasion ability of gastric cancer cells. Additionally, an MTT assay and clonogenic assay were performed to evaluate cell proliferation, and a cell cycle analysis was performed by propidium iodide staining. Furthermore, the expression of genes implicated in the ataxia telangiectasia mutated (ATM) pathway and proteins involved in cell cycle regulation were detected by polymerase chain reaction and western blot analyses. Results: Compared with control cells, gastric cancer cells transfected with si-SMYD3 showed lower migration and invasion abilities (P<0.05), and the absence of SMYD3 halted cells in G2/M phase and activated the ATM pathway. Furthermore, the opposite patterns were observed when SMYD3 was elevated in normal gastric cells. Conclusions: To the best of our knowledge, this study provides the first evidence that the absence of SMYD3 could inhibit the migration, invasion, and proliferation of gastric cancer cells and halt cells in G2/M phase via the ATM-CHK2/p53-Cdc25C pathway. These findings indicated that SMYD3 plays crucial roles in the proliferation, migration, and invasion of gastric cancer cells and may be a useful therapeutic target in human gastric carcinomas.

ATM Signaling Pathway Is Implicated in the SMYD3-mediated Proliferation and Migration of Gastric Cancer Cells

Wang, Lei,Wang, Qiu-Tong,Liu, Yu-Peng,Dong, Qing-Qing,Hu, Hai-Jie,Miao, Zhi,Li, Shuang,Liu, Yong,Zhou, Hao,Zhang, Tong-Cun,Ma, Wen-Jian,Luo, Xue-Gang The Korean Gastric Cancer Association 2017 Journal of gastric cancer Vol.17 No.4

Purpose: We previously found that the histone methyltransferase suppressor of variegation, enhancer of zeste, trithorax and myeloid-nervy-deformed epidermal autoregulatory factor-1 domain-containing protein 3 (SMYD3) is a potential independent predictive factor or prognostic factor for overall survival in gastric cancer patients, but its roles seem to differ from those in other cancers. Therefore, in this study, the detailed functions of SMYD3 in cell proliferation and migration in gastric cancer were examined. Materials and Methods: SMYD3 was overexpressed or suppressed by transfection with an expression plasmid or siRNA, and a wound healing migration assay and Transwell assay were performed to detect the migration and invasion ability of gastric cancer cells. Additionally, an MTT assay and clonogenic assay were performed to evaluate cell proliferation, and a cell cycle analysis was performed by propidium iodide staining. Furthermore, the expression of genes implicated in the ataxia telangiectasia mutated (ATM) pathway and proteins involved in cell cycle regulation were detected by polymerase chain reaction and western blot analyses. Results: Compared with control cells, gastric cancer cells transfected with si-SMYD3 showed lower migration and invasion abilities (P<0.05), and the absence of SMYD3 halted cells in G2/M phase and activated the ATM pathway. Furthermore, the opposite patterns were observed when SMYD3 was elevated in normal gastric cells. Conclusions: To the best of our knowledge, this study provides the first evidence that the absence of SMYD3 could inhibit the migration, invasion, and proliferation of gastric cancer cells and halt cells in G2/M phase via the ATM-CHK2/p53-Cdc25C pathway. These findings indicated that SMYD3 plays crucial roles in the proliferation, migration, and invasion of gastric cancer cells and may be a useful therapeutic target in human gastric carcinomas.

Piperlongumine decreases cell proliferation and the expression of cell cycle-associated proteins by inhibiting Akt pathway in human lung cancer cells

Seok, Jin Sil,Jeong, Chang Hee,Petriello, Michael C.,Seo, Han Geuk,Yoo, Hyunjin,Hong, Kwonho,Han, Sung Gu Elsevier 2018 Food and chemical toxicology Vol.111 No.-

<P><B>Abstract</B></P> <P>Piperlongumine (PL) is an alkaloid of a pepper plant found in Southeast Asia. PL is known to induce selective toxicity towards a variety of cancer cell types. To explore the possible anti-lung cancer effects of PL, A549 cells were treated with PL (0–40 μM) for 24 h. Alterations in the expression of cell cycle-associated proteins (cyclin D1, cyclin-dependent kinase 4 (CDK4), CDK6 and retinoblastoma (Rb)) and intracellular signaling molecules (extracellular signal receptor-activated kinase 1/2 (ERK1/2), Akt, p38 and nuclear factor-κB (NF-κB)) were examined in cells following treatment of PL using Western blot analysis. Results showed that proliferation of cells were significantly decreased by PL in a dose-dependent manner. Flow cytometry results demonstrated increased number of cells in G1 phase in PL (40 μM)-treated group. Reactive oxygen species was significantly increased in cells treated with PL at 20–40 μM. The expression of cyclin D1, CDK4, CDK6 and p-Rb were markedly decreased in cells treated with PL at 40 μM. Treatment of cells with PL suppressed phosphorylation of Akt but increased ERK1/2 phosphorylation. Treatment of PL significantly decreased nuclear translocation of NF-κB p65 in cells. These results suggest that PL possesses antiproliferative properties in A549 cells.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Piperlongumine decreases proliferation of A549 cells. </LI> <LI> The mechanism is through ROS generation and downregulated Akt pathway. </LI> <LI> Piperlongumine decreases protein expression of cycle-associated proteins. </LI> </UL> </P>

Effect of benzo(a)pyrene and mitomycine C on HeLa cell division cycle

Yu, Il-Je,Lim, Cheol-Hong,Kim, Hyo-Jung,Chung, Kyu-Hyuk,Song, Kyung-Seuk,Han, Jeong-Hee,Chung, Yong-Hyun Korean Environmental Mutagen Society 2001 한국환경성돌연변이·발암원학회지 Vol.21 No.2

Recently, there has been significant progress in understanding the control process of the cell division cycle. To investigate the influence of toxic substances on the cell cycle, the effect of benzo(a)pyrene (BAP) and mitomycine C (MMC) on synchronized HeLa cells was analyzed during the cell cycle. To synchronize the HeLa cells, 10$^{6}$ cells were grown for 1 day and then treated with 1 mM hydroxyurea for 14 h. The arrested cells were then allowed to proceed through their cell cycle by removing the hydroxyurea and resupplying a fresh medium. The arrested cells in the G1/S transition then proceeded to the S phase after 4 h, the G2/M phase after 8h, and the G1 phase after 12 h, subsequent to the resupply of a fresh medium. In the untreated HeLa cells, the p34$^{cdc2}$ kinase activity, measured using a p34$^{cdc2}$ specific peptide, peaked after 8h (G2/M) and then declined after 12 h (G1). However, treatment with 30 $\mu$M BAP delayed the peak of the p34$^{cdc2}$ kinase activity. The amount of p34$^{cdc2}$ remained unchanged in the untreated, BAP-, and MMC-treated cells throughout the cell cycle. The cyclin B level peaked after 8 h in the untreated cells, yet peaked after 10-12 h in the BAP-treated cells. There was no significant change in the cyclin B level in the MMC-treated cells.