WEE1 is an important factor for histone transcription, chromosome condensation and regulation of cell cycle progression. WEE1 kinase can phosphorylate Cdc2 and down-regulate Cdc2 kinase activity. It can regulate G2 to M phase transition and cell mitosis. It plays a key role in chromosome condensation delay and histone synthesis, suggesting the important functions of WEE1 in the occurrence and development in cancer. At present, a multiple WEE1 inhibitors have been discovered. A great progress has been made in combination of WEE1 inhibitors with DNA damage treatment (chemotherapy or radiotherapy), which makes WEE1 an important target in cancer treatment.
CDC2 Protein Kinase ; metabolism ; Cell Cycle ; Cell Cycle Proteins ; metabolism ; DNA Damage ; Histones ; metabolism ; Humans ; Neoplasms ; metabolism ; Nuclear Proteins ; metabolism ; Phosphorylation ; Protein-Tyrosine Kinases ; metabolism

OBJECTIVE: To investigate the expression of eIF3P170, cdc2, cyclinB1 and cyclinD1 in developing cardiac myocytes, and the correlation between eIF3P170 with cdc2, cyclin D1, and cyclin B1 in mice. METHODS: Mouse cardiac myocytes were obtained at different time points. RT-PCR was employed to detect the expression of eIF3P170, cdc2, cyclin D1 and cyclin B1 mRNA. RESULTS: Expressions of eIF3P170, cdc2, cyclinD1 and cyclinB1 mRNA were higher in the embryonic Day 13, 15, 18 and postnatal Day 1, 2, 3, 5. Expressions at postnatal Day 5 reached the highest (all P values<0.05 vs other time points), and then the expressions of these genes gradually decreased to the weakest at postnatal Day 30 (all P values<0.05 vs other time points). The mRNA expression of eIF3P170 was positively correlated with cdc2, cyclin D1 and cyclin B1 mRNA expression respectively. CONCLUSION The mRNA expressions of eIF3 P170, cdc2, cyclin D1 and cyclin B1 in the embryo and the early life after birth are high. They reach the maximum at postnatal Day 5, then gradually decreased.
Animals ; CDC2 Protein Kinase ; metabolism ; Cell Cycle ; Cyclin B1 ; metabolism ; Cyclin D1 ; metabolism ; Eukaryotic Initiation Factor-3 ; metabolism ; Mice ; Myocytes, Cardiac ; cytology ; metabolism ; RNA, Messenger

In an oxygen-depleted environment, endothelial cells initiate an adaptive pattern of synthesis, which may enable them to survive hypoxic crises. Using high-resolution two-dimensional gel electrophoresis in conjunction with mass spectroscopy, we obtained a 24 differential display of proteins in the pancreatic endothelial cell line, MS-1, at four time points following induction of hypoxia. The induction of Wee1 under hypoxia was confirmed both at the mRNA and protein levels. The phosphorylation of cell division cycle 2, which is downstream of Wee1, was also increased after hypoxic exposure. In addition, pre-exposure to hypoxia attenuated a decrease in hydrogen peroxide-induced cell number. The induction of bax (a pro-apoptotic protein) and reduction of bcl (an anti-apoptotic protein) after hypoxia stimulus were also attenuated by hypoxic pre-exposure. Moreover, hydrogen peroxide-induced morphologic damage did not appear in the wild-type Wee1-expressing cells. Taken together, our results suggest that Wee1 may have important role in hypoxia-induced pathophysiological situations in endothelial cells.
Animals ; CDC2 Protein Kinase/metabolism ; Cell Cycle Proteins/*genetics/metabolism ; Cell Hypoxia ; Cell Line ; Cell Survival ; Endothelial Cells/cytology/*metabolism ; *Gene Expression Regulation ; Hydrogen Peroxide/*metabolism ; Mice ; Nuclear Proteins/*genetics/metabolism ; Pancreas/cytology ; Phosphorylation ; Protein-Tyrosine Kinases/*genetics/metabolism

PURPOSE: Cell cycle progression is regulated by interactions of specific cyclins and cyclin dependent kinases (CDKs) at the G1-S and G2-M checkpoints and cell cycle deregulation plays a major role in carcinogenesis of human cancers. PATIENTS AND METHODS: To investigate the role of cell cycle regulators in the pathogenesis and progression of human gastric cancers, 23 cases of gastric carcinomas were examined for the expression of cyclin B1, p34cdc2, p27(Kip1) and p53 by immunohistochemical methods, and gene expression was correlated with various clinicopathologic findings. RESULTS: Out of 23 cases studied, cyclin B1 was diffusely expressed in 20 cases (87.0%), p34cdc2 in 14 cases (60.9%) and p53 in 12 cases (52.2%), whereas in normal gastric tissues, cyclin B1 and p34cdc2 were weakly expressed and p53 was not expressed. In contrast, p27(Kip1) was expressed in only 8.7% of gastric carcinomas compared with 78.3% of normal gastric tissues. There was correlation between the expression of cyclin B1 and expression of p34cdc2 (p=0.002), between the expression of cyclin B1 and loss of p27(Kip1) (p=0.025), and between the expression of p34cdc2 and loss of p27(Kip1) (p=0.065). In addition, expression of cyclin B1 was correlated with regional lymph node metastasis (p=0.032). CONCLUSION: Our results indicate that cyclin B1 and p34cdc2 are involved in the genesis or progression of gastric cancers. Furthermore, overexpression of cyclin B1 may play an important role in lymph node metastatic potential of gastric cancer. Thus, abnormal expression of cyclin B1 and CDKs, overexpression of p53 and loss of p27(Kip1) expression may play important roles in human gastric carcinogenesis.
Adult ; Aged ; CDC2 Protein Kinase/*metabolism ; Cyclin B/*metabolism ; Female ; Humans ; Intracellular Signaling Peptides and Proteins/*metabolism ; Male ; Middle Aged ; Prognosis ; Stomach Neoplasms/*diagnosis/metabolism ; Tumor Suppressor Protein p53/*metabolism

The human Gadd45 protein family plays critical roles in DNA repair, negative growth control, genomic stability, cell cycle checkpoints and apoptosis. Here we report the crystal structure of human Gadd45γ [corrected], revealing a unique dimer formed via a bundle of four parallel helices, involving the most conserved residues among the Gadd45 isoforms. Mutational analysis of human Gadd45γ [corrected] identified a conserved, highly acidic patch in the central region of the dimer for interaction with the proliferating cell nuclear antigen (PCNA), p21 and cdc2, suggesting that the parallel dimer is the active form for the interaction. Cellular assays indicate that: (1) dimerization of Gadd45γ [corrected] is necessary for apoptosis as well as growth inhibition, and that cell growth inhibition is caused by both cell cycle arrest and apoptosis; (2) a conserved and highly acidic patch on the dimer surface, including the important residues Glu87 and Asp89, is a putative interface for binding proteins related to the cell cycle, DNA repair and apoptosis. These results reveal the mechanism of self-association by Gadd45 proteins and the importance of this self-association for their biological function.
Amino Acid Motifs ; Animals ; Apoptosis ; radiation effects ; CDC2 Protein Kinase ; Cell Cycle ; Cell Survival ; Crystallography, X-Ray ; Cyclin B ; metabolism ; Cyclin-Dependent Kinase Inhibitor p21 ; metabolism ; Cyclin-Dependent Kinases ; HeLa Cells ; Humans ; Intracellular Signaling Peptides and Proteins ; chemistry ; genetics ; metabolism ; Mice ; Mutagenesis, Site-Directed ; Mutation, Missense ; Proliferating Cell Nuclear Antigen ; metabolism ; Protein Binding ; Protein Interaction Domains and Motifs ; Protein Multimerization ; Protein Structure, Quaternary ; Ultraviolet Rays

Acute Lung Injury ; chemically induced ; metabolism ; pathology ; Animals ; CDC2 Protein Kinase ; genetics ; metabolism ; Cell Cycle ; drug effects ; Checkpoint Kinase 1 ; Female ; Lung ; metabolism ; pathology ; ultrastructure ; Male ; Malondialdehyde ; metabolism ; Microscopy, Electron, Transmission ; Organometallic Compounds ; toxicity ; Oxidative Stress ; Protein Kinases ; genetics ; metabolism ; RNA, Messenger ; metabolism ; Rats ; Rats, Sprague-Dawley

Sphingosine kinase 1 (SphK1) plays critical roles in cell biological functions. Here we investigated the effects of SphK1 inhibitor SKI II on hepatoma HepG2 cell cycle progression and invasion. Cell survival was determined by SRB assay, cell cycle progression was assayed by flow cytometry, the ability of cell invasion was measured by Matrigel-Transwell assay and protein expression was detected by Western blotting. The results showed that SKI II markedly inhibited HepG2 cell survival in a dose-dependent manner, induced G1 phase arrest in HepG2 cell and inhibited cell invasion. SKI II markedly decreased the expressions of G1-phase-related proteins CDK2, CDK4 and Cdc2 and the levels of cell invasion-associated proteins MMP2 and MMP9. The results showed that SKI II inhibited cell cycle progression and cell invasion, implying SphK1 as a potential target for hepatoma treatment.
CDC2 Protein Kinase ; Cell Movement ; drug effects ; Cell Survival ; drug effects ; Cyclin-Dependent Kinase 2 ; metabolism ; Cyclin-Dependent Kinase 4 ; metabolism ; Cyclin-Dependent Kinases ; metabolism ; G1 Phase ; drug effects ; Hep G2 Cells ; Humans ; Matrix Metalloproteinase 2 ; metabolism ; Matrix Metalloproteinase 9 ; metabolism ; Phosphotransferases (Alcohol Group Acceptor) ; antagonists & inhibitors ; Thiazoles ; pharmacology

In the present study, a newly synthesized benzofuran lignan 4-formyl-2-(4-hydroxy-3methoxyphenyl)-5-(2-methoxycarbonyethyl)-7-methoxy-benzo [b] furan (ERJT-12) was tested for its antiproliferative activity on human tumor cells. The related mechanisms were also investigated. In vitro growth inhibitory effects of ERJT-12 on various cancer cell lines were determined by MTT assay. Cell cycle distribution and apoptosis were detected by flow cytometry. The integrity of DNA was assessed by agarose gel electrophoresis. Activation of Caspase-3/7 and Caspase-6 was measured by colorimetric assay. The expressions of cell cycle proteins cell divide cycle 25c (Cdc25c), cyclin dependent kinase 1 (CDK1), CyclinB1 and apoptosis-related proteins Bax and Bcl-2 were detected by Western blotting. MTT assay showed that ERJT-12 inhibited the proliferation of several cancer cell lines including multidrug resistant cells. MCF-7 cells were markedly arrested at gap2/mitosis (G2/M) phase after treatment with ERJT-12 and progressed into apoptosis. The increased activities of Caspase-3/7 and Caspase-6 in MCF-7 cells were observed. The expression of CyclinB1 was down-regulated. The activities of Cdc25c and CDK1 protein were suppressed and Bcl-2 protein was phosphorylated. ERJT-12 displays potent antiproliferative activity towards cancer cells through suppressing cell cycle proteins, arresting cell cycle at G2/M phase and inducing apoptosis. It might be a novel candidate for cancer therapy.
Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Benzofurans ; pharmacology ; CDC2 Protein Kinase ; metabolism ; Caspase 3 ; metabolism ; Caspase 6 ; metabolism ; Caspase 7 ; metabolism ; Cell Cycle Proteins ; metabolism ; Cell Division ; drug effects ; Cell Line, Tumor ; Cyclin B ; metabolism ; Cyclin B1 ; G2 Phase ; drug effects ; Humans ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; bcl-2-Associated X Protein ; metabolism ; cdc25 Phosphatases ; metabolism

OBJECTIVETo explore the influence of different nutritional support routes on the intestinal mucosal epithelial cell cycle in burned rats.

METHODSSixty-six Wistar rats inflicted with 30% TBSA III degree burns on the back were employed as the model and were randomly divided into enteral feeding group (EF) and intravenously parenteral nutrition group (PN). Equal volume of nutritional support fluid containing predetermined equal amount of calories and nitrogen was applied via feeding or intravenously infusion through external jugular vein. The indices were observed on 6, 12, 24, 48 and 72 postburn hours (PBHs) with the reference to those in 6 normal rats. The intestinal epithelial cell cycle in jejunal and ileal mucous membrane was analyzed by flow cytometry. Western blotting method was employed in the examination of the expression of cyclin D1, E and that of cyclin dependent kinase (CDK)2 and CDK4.

RESULTS(1) lntestinal mucosal epithelial G0/G1 ratio in jejunum in EF group was significantly lower than that in PN group at 72 PBHs (P < 0.05). While the ratio in ileum in EF was obviously higher than that in PN groups at 6, 12, 48 and 72 PBHs (P < 0.05). (2) The cell percentage of S phase in EF group was evidently higher than that in PN group (P < 0.05 - 0.01) at 48 and 72 PBHs. (3) Intestinal mucosal cyclin D1 expression increased significantly in EF group at 24 PBHs and in PN group at 48 PBHs (P < 0.05) and which in EF group was obviously higher than that in PN group at 72 PBHs (P < 0.05). (4) The expression of the intestinal mucosal cyclin E in EF group at 72 PBHs was evidently higher than the control value and that in PN group (P < 0.05). (5) The expression of CDK2 exhibited no obvious difference among PN,EF and control group (P < 0.05). The CDK4 expression in EF group increased obviously at 72 PBHs (P < 0.05).

CONCLUSIONEarly postburn enteral feeding was beneficial to the progression of intestinal mucosal epithelial cell cycle and to the repairing and renovation of injured intestinal mucosal membrane. Cyclin and CDK might be important in the modulation of the intestinal mucosal epithelial cell cycle.

Animals ; Burns ; metabolism ; pathology ; CDC2-CDC28 Kinases ; Cell Cycle ; physiology ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase 2 ; Cyclin-Dependent Kinase 4 ; Cyclin-Dependent Kinases ; metabolism ; Disease Models, Animal ; Enteral Nutrition ; Female ; G1 Phase ; physiology ; Intestinal Mucosa ; metabolism ; pathology ; Male ; Protein-Serine-Threonine Kinases ; metabolism ; Proto-Oncogene Proteins ; Rats ; Rats, Wistar ; Resting Phase, Cell Cycle ; physiology ; S Phase ; physiology

OBJECTIVETo elucidate the cytotoxicity and mechanism of 23-O-acetylcimigenol-3-O-beta-D-xylopyranoside isolated from C. dahurica on HepG2 cells and to find the leading compound for new drug development.

METHODMTT, AO/EB staining observation, flow cytometry and western blot methods were used to study the cytotoxicity, morphological changes, cell cycle distribution and protein expression profile of 23-O-acetylcimigenol-3-O-beta-D-xylopyranoside on HepG2 cells.

RESULT23-O-acetylcimigenol-3-O-beta-D-xylopyranoside could inhibit the proliferation of HepG2 cells with IC50 at 16 micromol x L(-1), and could also induce apoptosis and G2-M cell cycle arrest. Further study demonstrated that the compound could cleavage PARP, regulate protein expression of bcl-2 family and decrease the expression of cdc 2 and cyclin B.

CONCLUSION23-O-acetylcimigenol-3-O-beta-D-xylopyranoside exerts its cytotoxicity on HepG2 cells via apoptosis and G2-M arrest. In addition, caspases family activation, regulation of protein expression of bcl-2 family and down regulation of cdc 2 and cyclin B were involved in apoptosis and G2-M arrest induced by it.

Apoptosis ; drug effects ; CDC2 Protein Kinase ; metabolism ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cimicifuga ; chemistry ; Cyclin B ; metabolism ; Glycosides ; isolation & purification ; pharmacology ; Humans ; Liver Neoplasms ; metabolism ; pathology ; Plants, Medicinal ; chemistry ; Poly(ADP-ribose) Polymerases ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Triterpenes ; isolation & purification ; pharmacology ; bcl-2-Associated X Protein ; metabolism