• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1165-1169
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• 2013

To elucidate the role of PKG isoforms in transcriptional control of cyclin D1, we employed a series of expression vectors of PKG $1{\alpha}$ and PKG $1{\beta}$ which encode HA-tagged wild type and constitutively active (SD and ${\Delta}N$) mutants. Our present study demonstrates that both the constitutively active mutants of PKG $1{\beta}$ downregulate the transcription of cyclin D1 when transiently transfected in NIH3T3 cells, whereas PKG $1{\alpha}$ mutants show weak inhibition. We further studied the transcriptional regulators of cyclin D1, such as, c-fos, NF-${\kappa}B$, and CRE by using the luciferase reporter assay. Constitutively active mutants of PKG $1{\beta}$ showed marked transcriptional downregulation of c-fos in NIH3T3 cells, whereas PKG $1{\alpha}$ downregulated c-fos to a lesser extent. We also found that the constitutively active mutants of PKG negatively regulated the activation of NF-${\kappa}B$ and CRE, suggesting their involvement in the regulation of cyclin D1.

• Radiation Oncology Journal
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• v.16 no.4
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• pp.377-388
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• 1998

Purpose : To evaluate changes in expression of cell cycle related genes during apoptosis induced in HL60 cells by X-irradiation to understand molecular biologic aspects in mechanism of radiation therapy. Material and Methods : HL-60 cell line (promyelocytic leukemia cell line) was grown in culture media and irradiated with 8 Gr by linear accelerator (6 MV X-ray). At various times after irradiation, ranging from 3 to 48 hours were analyzed apoptotic DNA fragmentation assay for apoptosis and by western blot analysis and semi-quantitative RT-PCR for expression of cell cycle related genes (cyclin A, cyclin B, cyclin C, cyclin Dl, cyclin E, cdc2, CDK2, CDK4, $p16^{INK4a}$, $p21^{WAF1}$, $p27^{KIP1}$, E2F, PCNA and Rb). Results : X-irradiation (8 Gy) induced apoptosis in HL-60 cell line. Cycline A protein increased after reaching its peak 48 h after radiation delivery and cyclin E, E2F, CDK2 and RB protein increased then decreased after radiation. Radiation induced up-regulation of the expression of E2F is due to mostly increase of Phosphorylated retinoblastoma proteins (ppRb). Cyclin Dl, PCNA, CDC2, CDK4 and $p16^{INK4a}$ protein underwent no significant change at any times after irradiation. There was not detected $p21^{WAF1}$ and $p27^{KIP1}$ protein. Cyclin A, B, C mRNA decreased immediately after radiation and then increased at 12 h after radiation. Cyclin Dl mRNA increased immediately and then decreased at 48 h after radiation. After radiation, cyclin E mRNA decreased with the lapse of time. CDK2 mRNA decreased at 3h and increased at eh after radiation. CDK4 mRNA rapidly increased at 6 to 12 h after radiation. There was no change of expression of $p16^{INK4a}$ and not detected in expressin of $p21^{WAF1}$ and $p27^{KIP1}$ mRNA. Conclusion : We suggest that entry into S phase may contribute to apoptosis of HL60 cells induced by irradiation. Increase of ppRb and decrease of pRb protein are related with radiation induced auoptosis of HL60 cells and tosis of HL60 cells induced by irradiation. Increase of ppRb and decrease of PRb protein are related with radiation induced apoptosis of HL60 cells and this may be associated with induction of E2F and cyclinE/CDK2. These results support that $p21^{WAF1}$ and $p27^{KIP1}$ are not related with radiation induced-apoptosis.

• Journal of Life Science
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• v.21 no.8
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• pp.1067-1075
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• 2011

Coiled-coil domain-containing protein 98 (CCDC98) plays a role in G2/M DNA damage checkpoint pathways by recruiting breast cancer 1 (BRCA1)-A complex to the DNA-damaged sites. However, the molecular mechanism of CCDC98 on the DNA damage-induced G2/M checkpoint pathways is unclear. In this study, we identifed Wilms tumor 1-associating protein (WTAP) as a novel CCDC98-binding protein, using tandem affinity purification. We confirmed the association between CCDC98 and WTAP using in vivo and in vitro binding assays. We demonstrated that CCDC98 regulates cyclin B1 expression by affecting WTAP protein stability. Based on these results, we suggest that CCDC98 may act as a novel cell cycle regulator by regulating the expression level of cyclin B1.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.931-936
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• 2003

We investigated inhibitory effects of Hericium erinaceus on the growth of cancer cells and the expression of cell cycle regulators, cyclins. Anticancer effects of Hericium erinaceus extract and fractions against cancer cell lines including HepG2 and HT29 were investigated. The methanol extract, the hexane fraction, the chloroform fraction and the ethylacetate fraction of Hericiu erinacew inhibited growth of cancer cells but they had no effect on the cytotoxicity of normal human liver cells under the same conditions. As shown by western blot analysis, the expression of cyclin B1 known as cell cycle regulator was markedly decreased after treatment with Hericium erinaceus extract in HepG2 cells. These results suggest that antiproliferative effect of Hericaum erinaceus extract is associated with markedly decreased expression of cyclin B1.

• Journal of Microbiology and Biotechnology
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• v.32 no.6
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• pp.718-729
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• 2022

Esophageal squamous cell carcinoma (ESCC) is the most common primary esophageal malignancy with poor prognosis. Here, due to the necessity for exploring potential therapies against ESCC, we obtained the gene expression data on ESCC from the TCGA and GEO databases. Venn diagram analysis was applied to identify common targets. The protein-protein interaction network was constructed by Cytoscape software, and the hub targets were extracted from the network via cytoHubba. The potential hub nodes as drug targets were found by pharmacophore-based virtual screening and molecular modeling, and the antitumor activity was evaluated through in vitro studies. A total of 364 differentially expressed genes (DEGs) in ESCC were identified. Pathway enrichment analyses suggested that most DEGs were mainly involved in the cell cycle. Three hub targets were retrieved, including CENPF, CCNA2 (cyclin A), and CCNB1 (cyclin B1), which were highly expressed in esophageal cancer and associated with prognosis. Moreover, amentoflavone, a promising drug candidate found by pharmacophore-based virtual screening, showed antiproliferative and proapoptotic effects and induced G1 in esophageal squamous carcinoma cells. Taken together, our findings suggested that amentoflavone could be a potential cell cycle inhibitor targeting cyclin B1, and is therefore expected to serve as a great therapeutic agent for treating esophageal squamous cell carcinoma.

• Laboraroty Animal Research
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• v.34 no.4
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• pp.264-269
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• 2018

Cell cycle dysfunction can cause severe diseases, including neurodegenerative disease and cancer. Mutations in cyclin-dependent kinase inhibitors controlling the G1 phase of the cell cycle are prevalent in various cancers. Mice lacking the tumor suppressors $p16^{Ink4a}$ (Cdkn2a, cyclin-dependent kinase inhibitor 2a), $p19^{Arf}$ (an alternative reading frame product of Cdkn2a,), and $p27^{Kip1}$ (Cdkn1b, cyclin-dependent kinase inhibitor 1b) result in malignant progression of epithelial cancers, sarcomas, and melanomas, respectively. Here, we generated knockout mouse models for each of these three cyclin-dependent kinase inhibitors using engineered nucleases. The $p16^{Ink4a}$ and $p19^{Arf}$ knockout mice were generated via transcription activator-like effector nucleases (TALENs), and $p27^{Kip1}$ knockout mice via clustered regularly interspaced short palindromic repeats/CRISPR-associated nuclease 9 (CRISPR/Cas9). These gene editing technologies were targeted to the first exon of each gene, to induce frameshifts producing premature termination codons. Unlike preexisting embryonic stem cell-based knockout mice, our mouse models are free from selectable markers or other external gene insertions, permitting more precise study of cell cycle-related diseases without confounding influences of foreign DNA.

• Journal of Life Science
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• v.16 no.5
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• pp.828-833
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• 2006

Maize (Zea mays L.) pistil cell death and stamen cell arrest are pivotal process on the sex determination, which diverges from bisexual state of floral meristem to unisexual state in staminate or pistillate floret. We investigated the temporal and spatial distribution of cell cycle gene expression during maize sex determination. The positive regulatory genes of cell cycle, cyclin A, cyclin B, cyclin dependent kinase (CDK) and Mad2 were highly expressed in the developing pistil and stamen but the expression was disappeared in the dying pistil and arresting stamens. In contrast, the negative regulatory genes of cell cycle, Wee1 and CDK inhibitor (CKI) were expressed in the arresting stamens in the wild-type ear and tasselseed2 mutant tassel, however, these genes were not detected in dying pistil although the cyclin B gene expression was disappeared. These results suggest that both the pistil cell death and stamen cell arrest process in maize sex determination are involved in cell cycle regulation, but the different expression patterns of negative regulatory cell cycle genes in the arresting stamens and aborting pistils suggest that the two processes may have distinctive modes of action.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.108-108
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• 2018

In this study, we evaluated the anti-cancer effect of extracts of leaves (ST-L) and branches (ST-B) from Sageretia theezans in human colorectal cancer cells. ST-L and ST-B significantly inhibited the proliferation of human colorectal cancer cells, SW480. ST-L and ST-B decreased cyclin D1 protein level through the induction of cyclin D1 proteasomal degradation via $GSK3{\beta}$-dependent threonine-286 phosphorylation of cyclin D1. In addition, ST-L and ST-B increased HO-1 protein through p38, ROS and $GSK3{\beta}$-dependent Nrf2 activation. These findings suggest that ST-L and ST-B may have great potential for the development of anti-cancer drug to treat human colorectal cancer.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.6
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• pp.507-513
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• 2000

ErbB3/HER3 is a cell surface receptor which belongs to the ErbB/HER subfamily of receptor protein tyrosine kinases. When expressed in NIH/3T3 cells, ErbB3 can form heterodimeric coreceptor with endogenous ErbB2. Among known intracellular effectors of the ErbB2/ErbB3 are mitogen-activated protein kinase (MAPK) and phosphoinositide (PI) 3-kinase. In the present study, we studied relative contributions of above two distinct signaling pathways to the heregulin-induced mitogenic response via activated ErbB3. For this, clonal NIH-3T3 cell lines expressing wild-type ErbB3 and ErbB3 mutants were stimulated with $heregulin{\beta}_1$. While cyclin D1 level was markedly high and further increased by treatment of heregulin in cells expressing wild-type ErbB3, the elimination of either Shc binding or PI 3-kinase binding lowered both levels. This result was supported by the reduction of cyclin $D_1$ expression by preteatment with MAPK kinase inhibitor or PI 3-kinase inhibitor before stimulation with heregulin. In accordance with the cyclin $D_1$ expression, elimination of either Shc binding or PI 3-kinase binding reduced the heregulin-induced DNA synthesis and cell growth rate. Our results obtained by the comparison of wild-type and ErbB3 mutants indicate that the full induction of the cell cycle progression through $G_1/S$ phase by ErbB3 activation is dependent on both Shc/MAPK and PI 3-kinase signal transduction pathways.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.43 no.5
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• pp.324-330
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• 2017

Objectives: There are only a limited number of studies on cyclin D1 and p63 expression in oral squamous cell carcinoma (OSCC) and leukoplakia. This study compared cyclin D1 and p63 expression in leukoplakia and OSCC to investigate the possible correlation of both markers with grade of dysplasia and histological grade of OSCC. Materials and Methods: The study included a total of 60 cases, of which 30 were diagnosed with OSCC and 30 with leukoplakia, that were evaluated immunohistochemically for p63 and cyclin D1 expression. Protein expression was correlated based on grades of dysplasia and OSCC. Results: Out of 30 cases of OSCC, 23 cases (76.7%) were cyclin D1 positive and 30 cases (100%) were p63 positive. Out of 30 cases of leukoplakia, 21 cases (70.0%) were cyclin D1 positive and 30 (100%) were p63 positive (P<0.05). Conclusion: The overall expression of cyclin D1 and p63 correlated with tumor differentiation, and increases were correlated with poor histological grades, from well-differentiated to poorly-differentiated SCC. Increased cyclin D1 and p63 expression was associated with the severity of leukoplakia. Based on these results cyclin D1 and p63 products can be a useful tool for improved leukoplakia prognosis.