Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0677930 (primary tumor)
20,210 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Normal, nontumorous cells express cyclin proteins in an orderly, scheduled fashion, at a given phase of the cell cycle. Thus, cyclin B1 is synthesized during G2 and abruptly degraded during mitosis. The onset of cyclin E synthesis takes place in mid-G1, its maximal expression is at the time of cell entrance to S, and its degradation occurs during cell progression through S phase. In the present study, multiparameter flow cytometry was used to correlate expression of cyclin B1 or cyclin E with cell cycle position (estimated by cellular DNA content) in normal human proliferating lymphocytes as well as in T-cell MOLT-4 leukemia; promyelocytic HL-60 leukemia; histiocytic U937 lymphoma; MCF-7, T-47D, and Hs 587T breast carcinoma; Colo 320DM colon carcinoma; and the T-24 transitional cell carcinoma cell line. The scheduled expression of both cyclins, namely of cyclin B1 restricted to G2 + M cells and of cyclin E restricted to late G1 and early S cells, was observed only in normal lymphocytes and MOLT-4 cells. The cells of HL-60, U937, T-47D, and Hs 587T lines expressed both cyclins in an unscheduled ("ectopic") fashion, i.e., unrelated to cell cycle position. Colo 320DM cells showed unscheduled expression of cyclin E (i.e., during G2) but expression of cyclin B1 in this line was generally restricted to G2 + M cells. There were relatively few (10-12%) cells in MCF-7 and T-24 cell lines that expressed cyclin B1 or E in an unscheduled manner. It may be expected that the unscheduled expression of cyclins in tumor cells may lead to a loss of the regulatory mechanisms of cell cycle progression and that such feature of the tumor may be of prognostic value. There is a need, therefore, to conduct similar studies in primary tumor cells.
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PMID:Unscheduled expression of cyclin B1 and cyclin E in several leukemic and solid tumor cell lines. 804 72

The cell cycle is controlled by positive and negative regulators. Gene abnormalities and aberrant expressions of various cyclins/CDKs and CDK inhibitors may play a pivotal role in stomach carcinogenesis. To clarify the role of cyclin E, CDK inhibitor p27Kip1 and their target molecule, E2F-1 in tumor metastasis, we examined immunohistochemically the expression of cyclin E, p27Kip1 and E2F-1 in 23 gastric carcinomas and metastatic tumors of the lymph node. Most of gastric carcinomas with lymph node metastasis showed reduced p27Kip1 expression. p27Kip1 was negative in 39% (9/23) of primary tumors, while it was so in 52% (12/23) of lymph node metastases. By comparison of p27Kip1 expression in primary and metastatic tumors in individual cases, metastatic tumor cells in the lymph nodes were expressed at weaker levels than in those in primary tumors in 43% (10/23) of the cases. On the other hand, over 70% (17/23) and 50% (12/23) of the cases expressed cyclin E and E2F-1 at nearly the same levels in both primary tumor and lymph node metastasis, respectively. These results suggest that tumor cells with reduced p27Kip1 expression may selectively metastasize to lymph node or distant organs.
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PMID:Expression of p27Kip1, cyclin E and E2F-1 in primary and metastatic tumors of gastric carcinoma. 1042 91

The investigation of molecular and genetic changes in gastric cancer has brought new insights into the pathogenesis of the disease. Knowledge of the genetic abnormalities and altered molecules could be used for differential diagnosis in case of an unknown primary tumor, allows their evaluation as prognostic factors, and could open novel avenues for more specific clinical interventions. Clinically relevant molecules whose expression or structure is altered include the plasminogen activator and its inhibitor plasminogen activator inhibitor type 1, the cell cycle regulator cyclin E, epidermal growth factor, the apoptosis inhibitor bcl-2, the cell adhesion molecule E-cadherin, and the multifunctional protein beta-Catenin. In addition, genetic instability is commonly seen. Gene amplification and protein overexpression of the growth factor receptors c-erbB2 and K-sam may be prognostic factors for intestinal- and diffuse-type gastric cancer, respectively. There has long been evidence for a genetic predisposition to gastric cancer by epidemiological studies and case reports. Very recently, germ line mutations of E-cadherin have been identified that are responsible for a dominantly inherited from of diffuse-type gastric cancer and could be used to identify individuals that are at high risk. The clinical implications of the recent findings for diagnosis, prognosis, therapy, and risk assessment are discussed.
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PMID:The use of molecular biology in diagnosis and prognosis of gastric cancer. 1152 6

The eukaryotic cell cycle is regulated by a family of serine/threonine protein kinases known as cyclin-dependent kinases (CDKs). The activation of a CDK is dependent on its association with a cyclin regulatory subunit. The formation of distinct cyclin-CDK complexes controls the progression through the first gap phase (G(1)) and initiation of DNA synthesis (S phase). These complexes are in turn regulated by protein phosphorylation and cyclin-dependent kinase inhibitors (CKIs). Cyclin E2 has emerged as the second member of the E-type cyclin family. Cyclin E2-associated kinase activity is regulated in a cell cycle dependent manner with peak activity at the G(1) to S transition. Ectopic expression of cyclin E2 in human cells accelerates G(1), suggesting that cyclin E2 is rate limiting for G(1) progression. Although the pattern and level of cyclin E2 expression in some primary tumor and normal tissue RNAs are distinct from cyclin E1, both E-type cyclins appear to have inherent functional redundancies. This functional redundancy has facilitated the rapid characterization of cyclin E2 and uncovered unique features associated with each E-type cyclin.
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PMID:Cyclin E2, the cycle continues. 1185 29

To account for the accumulation of genomic alterations required for tumor progression, it has been suggested that the genomes of cancer cells are unstable and that this instability results from defective mutators (the "mutator phenotype" theory). To examine the hypothesis that abnormal cell-cycle regulators act as the mutators contributing to genomic instability, the present study, based on primary tumor tissues from 71 patients with breast cancer, was performed to determine whether there was an association between aberrant expression of cell-cycle regulators (cyclin A, cyclin D1, cyclin E, RB1, p21, and p27) and chromosomal instability. Comparative genomic hybridization was used to measure chromosomal changes, reflecting genomic instability in individual tumors, whereas immunohistochemistry was used to detect aberrant expression of cell-cycle regulators. Overexpression of cyclin D1 was found to be significantly correlated with increased chromosomal instability (defined as harboring more than 7 chromosomal changes), with 63% of tumors overexpressing and 27% of tumors not overexpressing, with cyclin D1 showing chromosomal instability (P < 0.05). Interestingly, this relationship was independent of cell outgrowth (as detected by the proliferation marker Ki-67) and was particularly significant in tumors not expressing p27 or in tumors with detectable RB1. These results suggest that cyclin D1 plays an alternative role in the regulation of genomic stability.
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PMID:Aberrant expression of cell-cycle regulator cyclin D1 in breast cancer is related to chromosomal genomic instability. 1200 88

The aim of the present study was to examine the prognostic significance of p27(Kip1) and cyclin E expression in patients with spindle-cell soft tissue sarcomas. In 46 cases of spindle-cell sarcoma including 17 pre-operative biopsy materials, the expression of p27(Kip1) and cyclin E was immunohistochemically examined. The expression of p27(Kip1) decreased in the nuclei of metastatic primary tumor cells (stage IV), whereas the expression of cyclin E increased in those lesions. On univariate analysis, when the expression of p27(Kip1) and cyclin E was analyzed together, patients with spindle-cell sarcoma exhibiting low expression of p27(Kip1) and high expression of cyclin E showed lower distant-metastasis-free survival (DMFS) and overall survival (OS) than those with other combinations of the two parameters (both P < 0.0001). Multivariate analysis revealed that patients with low p27(Kip1) and high cyclin E expression also showed a decrease in DMFS (P = 0.0007, relative risk = 21.3) and OS (P = 0.005, relative risk = 20.8). These results suggest that the combination analysis of p27(Kip1) and cyclin E expression even in biopsy specimens allows the prediction of the clinical behavior of spindle-cell sarcoma.
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PMID:The prognosis in spindle-cell sarcoma depends on the expression of cyclin-dependent kinase inhibitor p27(Kip1) and cyclin E. 1282 85

Although tumor growth is controlled by growth rate and cell cycle, it is also likely that the proliferative activity of tumor cells can influence the growth rate of the primary cancer and account for their aggressiveness. Variations in growth rate, cell cycle control and proliferative activity could, in part, explain differences in invasive and metastatic properties among non-small cell lung carcinomas (NSLC). The purpose of this report is to: (1) evaluate growth rate by using growth- and cell cycle-regulating markers (mitotic count, nuclear star volume, AgNOR, and Ki-67) as reflections of growth rate and (2) compare the indices of primary NSLC with the indices of their metastasis in a series of patients with advanced disease. Thirty-three patients with non-small cell lung cancer and hematogenous metastases were retrospectively studied by histochemical, immunohistochemical, and morphometrical investigations. Clinical variables were examined for differences in the frequency of histological subtypes, nuclear star volume, mitotic index, AgNOR area, and Ki-67 immunohistochemistry indices of expression in subgroups of patients stratified by primary tumor and hematogenic metastasis. The impact of these factors on overall follow-up was analyzed. In the samples available in this study, consisting of primary-met paired tumors, which are unique and rarely available for studies of lung cancer, we found that nuclear star volume and mitotic index in metastatic tumors were significantly higher than in the primary tumors. Although there was no significant difference between the Ki-67 index of metastatic and primary tumors, the Ki-67 index in metastatic brain tumors was significantly higher than in the corresponding primary tumors. Examination of Kaplan-Meier survival curves demonstrated that patients with metastatic tumors showing AgNOR area higher than 10.82 microm2 and nuclear star volume lower than 559.50 microm3 had approximately the same odds ratio (log rank of 4.16 and 3.25, p = 0.04 and 0.01, respectively) for survival with a median survival time equal to 17 months for both groups. Analysis of the remaining marker correlation had no impact on survival. We conclude that these results offer future possibilities for more complex studies, including the results of additional immunohistochemical analysis using molecular markers that are known to be important in regulating cell proliferation, e.g., cyclin D1, p27, and cyclin E. These would influence clinical decisions or different therapeutic approaches in advanced stage disease of non-small cell lung cancer.
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PMID:Nuclear markers (star volume, mitotic index, AgNOR and Ki-67) of the primary tumor and its metastasis in non-small cell lung carcinomas. 1515 46

A mammary tumor cell line, designated MTCL, was successfully established from a mouse primary mammary tumor (MTP). The MTCL cells retain cytokeratin and both estrogen receptor (ER) and progesterone receptor (PR) in vitro. In vitro exposure of MTCL cells to progesterone causes a decrease in the cellular (3)H-thymidine uptake, indicating an inhibition by progesterone on MTCL cellular deoxyribonucleic acid synthesis, whereas exposure of the cells to a high dose of estrogen (15 pg/ml) for 48 h causes an increase of (3)H-thymidine uptake. We inoculated both MTP or MTCL tumor cells into normal cycling female C(3)HeB/FeJ mice and demonstrated that the post-resection metastatic recurrence of MTCL tumors, like the original MTP tumors, depends on the time of tumor resection within the mouse estrous-cycle stage. Both MTCL and MTP tumors have similar histological appearances with the exception of less extensive tumor necrosis and higher vascularity in MTCL tumors. Equivalent levels of sex hormone receptors (ER alpha, ER beta, and PR), epithelial growth hormone receptors (Her2/neu, EGFR1), tumor suppressors (BRCA1, P53), and cell apoptosis-relevant protein (bcl-xl) were found in these in vivo tumors by immunohistochemistry. Cyclin E protein, however, was significantly higher in MTP tumors compared with MTCL tumors. Our results indicate that MTCL cells retain many of the biologic features of the original MTP primary tumor cells, and to our knowledge, it is the first in vitro cell line that has been shown to maintain the estrous-cycle dependence of in vivo cancer metastasis.
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PMID:Creation of a stable mammary tumor cell line that maintains fertility-cycle tumor biology of the parent tumor. 1516 41

The genetic mechanisms that control proliferation of childhood musculoskeletal malignancies, notably Ewing's tumor (ET) and rhabdomyosarcoma (RMS), remain largely unknown. Most human cancers appear to overexpress at least one of the G1 cyclins (cyclins D1, D2, D3, E1, and E2) to bypass normal regulation of cell cycle G1 progression. We compared the gene expression profiles of 7 ET and 13 RMS primary tumor samples and found overexpression of cyclin D1 in all 7 ET samples. In contrast, RMS samples expressed higher levels of cyclin D2, cyclin D3, and cyclin E1. This was confirmed by quantitative reverse transcription-polymerase chain reaction and Western blot. The relative roles of RAS-extracellular signal-regulated kinase 1/2 and phosphatidylinositol 3'-kinase (PI3K)-AKT pathways in the regulation of D-type cyclin expression in these tumors were then assessed. Inhibition of either pathway reduced expression of cyclins D1, D2, and D3 in RMS lines, whereas only PI3K inhibitors blocked cyclin D1, D2, and D3 expression in ET lines. Furthermore, PI3K-AKT appeared to regulate D-type cyclin transcription in RMS lines through FKHR and FKHRL1. Finally, the role of the ET-associated EWS-FLI1 fusion gene in regulating D cyclin expression was studied. Inhibition of EWS-FLI1 expression in the TC71 ET line decreased cyclin D1 levels but increased cyclin D3 levels. In contrast, induction of EWS-FLI1 expression in the RD RMS cell line increased cyclin D1 expression but decreased cyclin D3 expression. Our results demonstrate distinct regulation of D-type cyclins in ET and RMS and indicate that EWS-FLI1 can modulate the expression of D-type cyclins independent of cellular backgrounds.
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PMID:Selective usage of D-Type cyclins by Ewing's tumors and rhabdomyosarcomas. 1534 83

The identification of genetic and epigenetic alterations from primary tumor cells has become a common method to identify genes critical to the development and progression of cancer. We seek to identify those genetic and epigenetic aberrations that have the most impact on gene function within the tumor. First, we perform a bioinformatic analysis of copy number variation (CNV) and DNA methylation covering the genetic landscape of ovarian cancer tumor cells. We separately examined CNV and DNA methylation for 42 primary serous ovarian cancer samples using MOMA-ROMA assays and 379 tumor samples analyzed by The Cancer Genome Atlas. We have identified 346 genes with significant deletions or amplifications among the tumor samples. Utilizing associated gene expression data we predict 156 genes with altered copy number and correlated changes in expression. Among these genes CCNE1, POP4, UQCRB, PHF20L1 and C19orf2 were identified within both data sets. We were specifically interested in copy number variation as our base genomic property in the prediction of tumor suppressors and oncogenes in the altered ovarian tumor. We therefore identify changes in DNA methylation and expression for all amplified and deleted genes. We statistically define tumor suppressor and oncogenic features for these modalities and perform a correlation analysis with expression. We predicted 611 potential oncogenes and tumor suppressors candidates by integrating these data types. Genes with a strong correlation for methylation dependent expression changes exhibited at varying copy number aberrations include CDCA8, ATAD2, CDKN2A, RAB25, AURKA, BOP1 and EIF2C3. We provide copy number variation and DNA methylation analysis for over 11,500 individual genes covering the genetic landscape of ovarian cancer tumors. We show the extent of genomic and epigenetic alterations for known tumor suppressors and oncogenes and also use these defined features to identify potential ovarian cancer gene candidates.
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PMID:Identification of tumor suppressors and oncogenes from genomic and epigenetic features in ovarian cancer. 2217 24


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