Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.11.22 (cdc2)
 8,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although aberrant expression of several cell-cycle regulators has been reported in endometrial carcinoma, correlations among these factors and their prognostic significance have not fully been elucidated. In the present study, expression of cyclins (D1, E, A, and B1), cyclin-dependent kinases (cdk2, cdk4, and cdc2), and tumor-suppressor gene products (p53, p21, and p27) were systematically examined by immunohistochemistry in 82 cases of endometrial carcinoma and 20 normal endometria. Results were compared with the expression of Ki-67, sex steroid receptor status, clinicopathological parameters, and patient outcomes. Positive staining for cyclin D1, cyclin E, cyclin A, cyclin B1, cdk2, cdk4, cdc2, p53, p21, and p27 was observed in 63%, 66%, 31%, 32%, 51%, 77%, 71%, 43%, 35%, and 60% of the 82 carcinomas, respectively. Among these factors, positive staining for cyclin D1, cdk4, and p53 was significantly frequent in advanced-stage tumors, and that for cyclin D1, cyclin A, cdk4, p21, and p53 was more frequent in higher-grade tumors. High correlation was found between cyclin A and p53 expression, between cyclin D1 and cdk4 expression, between cdk4 and Ki-67 expression, and between p21 and Ki-67 expression. Multivariate analysis showed that the factors for poor prognosis were advanced stage and cyclin A positivity. These findings suggest that various cell-cycle regulators are involved in activated cell growth of endometrial carcinoma, and that positive staining for cyclin A could be a useful marker for unfavorable patient prognosis.
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PMID:Immunohistochemical expression of cyclins, cyclin-dependent kinases, tumor-suppressor gene products, Ki-67, and sex steroid receptors in endometrial carcinoma: positive staining for cyclin A as a poor prognostic indicator. 1279 21

Expression of cell cycle-regulating genes was studied in human myeloid leukemia cell lines ML-1, ML-2 and ML-3 during induction of differentiation in vitro. Myelomonocytic differentiation was induced by phorbol ester (12-o-Tetradecanoyl-phorbol-13-acetate, TPA), tumor necrosis factor alpha (TNFalpha) or interferon gamma (INFgamma), or their combination. Differentiation (with the exception of TNFalpha alone) was accompanied by inhibition of DNA synthesis and cell cycle arrest. Inhibition of proliferation was associated with a decrease in the expression of cdc25A and cdc25B, cdk6 and Ki-67 genes, and with increased p21(Waf1/Cip1) gene expression, as measured by comparative RT-PCR. Expression of the following genes was not changed after induction of differentiation: cyclin A1, cyclin D3, cyclin E1 and p27(Kip1). Surprisingly, cyclin D1 expression was upregulated after induction by TPA, TNFalpha with IFNgamma or BA. Cyclin D2 was upregulated only after induction by BA. The results of the expression of the tested genes obtained by comparative RT-PCR were confirmed by quantitative real-time (RQ) RT-PCR and Western blotting. Quantitative RT-PCR showed as much as a 288-fold increase of cyclin D1 specific mRNA after a 24h induction by TPA. The upregulation of cyclin D1 in differentiating cells seems to be compensated by the upregulation of p21(Waf1/Cip1). These results, besides others, point to a strong correlation between the expression of cyclin D1 and p21(Waf1/Cip1) on the one hand and differentiation on the other hand in human myeloid leukemic cells and reflect a rather complicated network regulating proliferation and differentiation of leukemic cells.
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PMID:Relationship between cyclin D1 and p21(Waf1/Cip1) during differentiation of human myeloid leukemia cell lines. 1292 50

Previous studies have demonstrated that the G2-M modulators contribute to the progression of human neoplasms. In this study, we investigated the expression of these modulators, cyclin-dependent kinase 1 (cdc2), and G2 cyclins, cyclin A and cyclin B1, in primary thyroid lymphoma. Cdc2 immunoexpression was observed in 51.0% of the 49 cases examined and was related to grade of malignancy, high Ki-67 labeling index, and aberrant p53 expression. The incidences of immunoexpression of cyclin A and cyclin B1 were 63.3% and 40.9%, respectively, and they were also related to the above three parameters. Furthermore, a correlation was found between the immunoexpression of cdc2 and G2 cyclins. These findings suggest that the cdc2 and G2 cyclins play an important role in the progression of thyroid malignant lymphoma.
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PMID:Cdc2 expression in primary thyroid lymphoma: its relationship with biological aggressiveness and G2 cyclins. 1453 37

p14 activates p53 by inhibiting MDM2 expression and arrests the cell cycle in G1 and G2/M. Abnormal p14 expression has been reported in various human cancers. This study investigated p14 expression in endometrioid adenocarcinoma of the uterine corpus in an attempt to clarify its correlation with other cell cycle-regulators and clinicopathologic parameters. The specimen studied consisted of 124 endometrioid adenocarcinomas, 20 normal endometria, and 20 endometrial hyperplasias. Immunohistochemical staining of formalin-fixed and paraffin-embedded tissues was performed using a Catalyzed Signal Amplification System. Cells with >5% positive staining were classified as positive for p14. A staining score of 1 was adopted when the percentage of positive nuclei was <5%, a score of 2 when it was 5 to 50%, and a score of 3 when it was >50%. In normal endometrium, the frequency of positive staining in the proliferative phase and secretory phase was 50% (4/8) and 58.3% (7/12), with staining scores of 1.8+/-0.9 and 1.6+/-0.5, respectively. The frequency of staining in simple hyperplasia (SH), complex hyperplasia (CH), and complex atypical hyperplasia (CAH) was 88.9% (8/9), 25% (1/4), and 42.9% (3/7), respectively; the staining scores were 1.9+/-0.3, 1.3+/-0.5, and 1.4+/-0.5, respectively. Among endometrioid adenocarcinomas, the frequency of staining of well-differentiated (G1), moderately differentiated (G2), and poorly differentiated (G3) adenocarcinomas was 69% (49/71), 64% (16/25), and 42.9% (12/28) respectively, with staining scores of 2.1+/-0.8, 2+/-0.9, and 1.8+/-1, respectively. Thus expression levels of p14 were higher in G1 tumors than in normal endometria or endometrial hyperplasias, and the frequency of its staining in endometrioid carcinomas was inversely correlated with histologic grade. The staining score for endometrioid adenocarcinomas also was inversely correlated with the labeling index (LI) of Ki-67, but not with that of cyclin A, cyclin D1, cyclin E, cdk2, p27, p53, or other clinicopathologic parameters. In conclusion, p14 expression correlated with histologic grade and Ki-67, but not other prognostic factors in endometrioid adenocarcinoma. Long-term follow-up studies are needed to analyze the significance of p14 expression in these tumors.
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PMID:Expression of tumor suppressor gene product p14ARF in endometrioid adenocarcinoma of the uterine corpus. 1521 99

To elucidate carcinogenesis in the endometrium, we investigated cyclin D1 immunoreactivities in 20 normal endometria, 20 endometrial hyperplasias and 141 endometrioid-type endometrial adenocarcinoma. We also evaluated the correlation of cyclin D1 expression with Ki-67, cyclin E, cyclin A, cdk2, p27 and p53, and clinicopathological parameters and prognosis. Cyclin D1 expression increased significantly with histological grade, and the labeling index (LI) for cyclin D1 was 121 +/- 23.4% in G1, 12.7 +/- 23.7% in G2 and 15.7 +/- 18.5% in G3. The LIs were significantly correlated with those for cyclin E, cyclin A and Ki-67, but not with the LIs of cdk2, p27 or p53. In contrast, high cyclin D1 expression was significantly correlated with low p53 expression. Cyclin D1 expression was not significantly correlated with any of the clinicopathological parameters except histological grade. Cyclin D1 expression was significantly correlated with histological grade and proliferative activity, but not clinicopathological parameters and prognosis in endometrial adenocarcinoma.
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PMID:Cyclin D1 expression in endometrioid-type endometrial adenocarcinoma is correlated with histological grade and proliferative activity, but not with prognosis. 1533 Jan 59

Melanoma accounts for only about 4% of all skin cancer cases but most of skin cancer-related deaths. Standard systemic therapies such as interferon (IFN) have not been adequately effective in the management of melanoma. Therefore, novel approaches are needed for prevention and treatment of this disease. Chemoprevention by naturally occurring agents present in food and beverages has shown benefits in certain cancers including nonmelanoma skin cancers. Here, employing 2 human melanoma cell lines (A-375 amelanotic malignant melanoma and Hs-294T metastatic melanoma) and normal human epidermal melanocytes (NHEM), we studied the antiproliferative effects of epigallocatechin-3-gallate (EGCG), the major polyphenolic antioxidant present in green tea. EGCG treatment was found to result in a dose-dependent decrease in the viability and growth of both melanoma cell lines. Interestingly, at similar EGCG concentrations, the normal melanocytes were not affected. EGCG treatment of the melanoma cell lines resulted in decreased cell proliferation (as assessed by Ki-67 and PCNA protein levels) and induction of apoptosis (as assessed cleavage of PARP, TUNEL assay and JC-1 assay). EGCG also significantly inhibited the colony formation ability of the melanoma cells studied. EGCG treatment of melanoma cells resulted in a downmodulation of anti-apoptotic protein Bcl2, upregulation of proapoptotic Bax and activation of caspases -3, -7 and -9. Furthermore, our data demonstrated that EGCG treatment resulted in a significant, dose-dependent decrease in cyclin D1 and cdk2 protein levels and induction of cyclin kinase inhibitors (ckis) p16INK4a, p21WAF1/CIP1 and p27KIP1. Our data suggest that EGCG causes significant induction of cell cycle arrest and apoptosis of melanoma cells that is mediated via modulations in the cki-cyclin-cdk network and Bcl2 family proteins. Thus, EGCG, alone or in conjunction with current therapies, could be useful for the management of melanoma.
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PMID:Anti-proliferative and proapoptotic effects of (-)-epigallocatechin-3-gallate on human melanoma: possible implications for the chemoprevention of melanoma. 1560 35

Bcl-2 phosphorylation is a normal physiological process occurring at mitosis or during mitotic arrest induced by microtubule damaging agents. The consequences of Bcl-2 phosphorylation on its function are still controversial. To better understand the role of Bcl-2 phosphorylation in mitosis, we studied the subcellular localization of phosphorylated forms of Bcl-2. Immunofluorescence experiments performed in synchronized HeLa cells indicate for the first time that mitotic phosphorylated forms of Bcl-2 can be detected in nuclear structures in prophase cells together with nucleolin and Ki-67. In later mitotic stages, as previously described, phosphorylated forms of Bcl-2 are localized on mitotic chromosomes. In addition, we demonstrate that Bcl-2 in these structures is at least in part phosphorylated on the T56 residue. Then, coimmunoprecipitation experiments reveal that, in cells synchronized at the onset of mitosis, Bcl-2 is present in a complex with nucleolin, cdc2 kinase and PP1 phosphatase. Taken together, these data further support the idea that Bcl-2 could have a new function at mitosis.
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PMID:Localization of phosphorylated forms of Bcl-2 in mitosis: co-localization with Ki-67 and nucleolin in nuclear structures and on mitotic chromosomes. 1587 60

The developmental processes of the oligodendrocyte progenitor cell (OPC) lineage that are targeted by interferon-gamma (IFN-gamma) were studied in primary rat OPC cultures. Under conditions of thyroid hormone-mediated oligodendrocyte differentiation, IFN-gamma produced a dose-dependent apoptotic response in OPCs. The lowest dose tested (15 ng/ml or 75 U/ml) was nonapoptotic, but activated detectable STAT1 DNA-binding. At this dose, IFN-gamma reduced the percentage of mature O1+ cells and increased the percentage of immature A2B5+ OPCs. This was observed without significant change in total cell number and cytotoxicity, and was accompanied by an increase in BrdU-labeled A2B5+ and O4+ cells. FACS analysis confirmed a lack of apoptotic sub-G1 cells and revealed a greater percentage of S- and G2/M-phase OPCs with IFN-gamma treatment. Dual immunostaining with Ki-67 and Olig2 showed a smaller percentage of Olig2+ cells in G0 phase in IFN-gamma-treated OPCs, indicating loss of G1 control. Instead, increased levels and phosphorylation of the checkpoint protein p34cdc2 by IFN- suggested increased partial arrest in G2. IFN-gamma not only sustained expression of PCNA and the G1-S regulators retinoblastoma protein, cyclin D1, cyclin E, and cdk2, but also decreased p27 levels. In addition to changes in cell proliferation and differentiation, IFN-gamma attenuated myelin basic protein (MBP) expression significantly, which was associated with decreased expression of both MBP and Sox10 RNAs. These findings indicate that IFN-gamma not only maintains cell cycle activity that could predispose OPCs to apoptosis, but also overrides G1-G0 signals leading to thyroid hormone-mediated terminal differentiation and myelin gene expression.
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PMID:Interferon-gamma inhibits cell cycle exit in differentiating oligodendrocyte progenitor cells. 1592 Jul 31

Gastrointestinal stromal tumors (GISTs) have a wide spectrum of biologic behavior ranging from benign to malignant. Risk grading based on tumor size and mitotic counts has been proposed in an effort to predict the adverse outcome of GIST in the literature so far. Recent molecular studies have reported the prognostic values of several parameters, including alteration of cell-cycle regulators. The aim of this study was to elucidate the prognostic values of risk grade and alterations of cell-cycle-related proteins, including Ki-67, cyclin A, cyclin B1, cyclin D1, cyclin E, p16, p21, p27, p53, cdc2, and cdk2, in addition to the conventional factors. Eighty cases of primary c-kit-positive GISTs were classified into 2 cases of very-low-risk grade, 20 cases of low-risk grade, 25 cases of intermediate-risk grade, and 33 cases of high-risk grade. The risk grade was correlated with the presence of metastases and/or recurrence. A high level of Ki-67 and cyclin A expression was correlated with risk grade (P = .0027 and .0441, respectively). Overexpression of G2-M regulators, such as cyclin A, cyclin B1, and cdc2, was associated with the Ki-67 labeling index (LI) (P = .0007, .0475, and .0040, respectively). According to univariate analysis, tumor grade (high risk), tumor size (> or =5 cm), mitotic counts (> or =5/50 high-power fields), Ki-67 LI (> or =4.92%), cyclin A LI (> or =1.61%), and cdc2 LI (> or =1.25%) were all found to be significantly associated with a shorter period of disease-free survival (P = .0001, .0270, .0004, .0001, .0001, and .0011, respectively). According to multivariate analysis, both high Ki-67 LI and high-risk grade were found to be significantly associated with a shorter period of disease-free survival (P = .0083 and .0246, respectively). In conclusion, our results strongly support the hypothesis that Ki-67 LI and risk grade are useful for predicting the aggressive biologic behavior of GISTs. Furthermore, alteration of G2-M regulators, such as cyclin A, cyclin B1, and cdc2, is also a useful marker for predicting aggressive behavior and play an important role, at least in part, in the cell proliferation of GIST.
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PMID:Prognostic significance of expressions of cell-cycle regulatory proteins in gastrointestinal stromal tumor and the relevance of the risk grade. 1608 54

We describe the immunohistochemical profile of rare primary squamous carcinoma of the clitoris metastasizing to the bilateral inguinal lymph nodes. Several antigens were assessed immunohistochemically (pRb1, p16INK4A, cyclin D1, cdk4, estrogen receptor (ER), progesterone receptor (PR), androgen receptor (AR), p53, Ki-67, p27KIP1, PTEN, hMLh1, phospho-AKT, collagen IV, leptin and CD90) in both tumors. All the antibodies applied revealed a staining pattern that is typical of primary and metastatic carcinomas. Cyclin D1-cdk4 complex was overexpressed, whereas there was no p16INK4A immunostaining. Moreover, both tumors expressed positivity for p53 protein, but were negative for estrogen and progesterone receptors. The proliferative activity of cancer, assessed by MIB-1 Proliferative Index, amounted to 25% either for primary or for metastatic tumors. As a conclusion, immunohistochemical assessment of various cell-cycle-associated molecules yield clues as to their possible function during the process of spread of rare neoplasm originating from the clitoris.
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PMID:The immunohistochemical profile of the primary and metastatic carcinoma of the clitoris: a case report. 1616 59


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