Cyclin E is a G1 cyclin essential for G1 to S-phase transition of the cell cycle with a profound role in oncogenesis. In tumor cells and tissues, cyclin E is overexpressed and present in its lower molecular weight (LMW) isoforms, and it can be used as a prognosticator for poor patient outcome. In this study, we have examined differences in the processing of cyclin E between normal mammary epith...

Cyclin E is a G1 cyclin that has been shown to be one of the key regulators of the G1-S transition and could consequently be a deregulated molecule in tumors. In the present study, we have characterized cyclin E expression by immunohistochemistry in 217 resected non-small cell lung cancers (NSCLCs) and found large variations in cyclin E expression among tumors. High-level cyclin E expression (a...

Cyclin E is a G1 cyclin essential for G1 to S-phase transition of the cell cycle with a profound role in oncogenesis. In tumor cells and tissues, cyclin E is overexpressed and present in its lower molecular weight (LMW) isoforms, and it can be used as a prognosticator for poor patient outcome. In this study, we have examined differences in the processing of cyclin E between normal mammary epith...

Early cell cycles of Xenopus laevis embryos are characterized by rapid oscillations in the activity of two cyclin-dependent kinases. Cdk1 activity peaks at mitosis, driven by periodic degradation of cyclins A and B. In contrast, Cdk2 activity oscillates twice per cell cycle, despite a constant level of its partner, cyclin E. Cyclin E degrades at a fixed time after fertilization, normally corres...

The SCF(FBW7) ubiquitin ligase degrades proteins involved in cell division, growth, and differentiation and is commonly mutated in cancers. The Fbw7 locus encodes three protein isoforms that occupy distinct subcellular localizations, suggesting that each has unique functions. We used gene targeting to create isoform-specific Fbw7-null mutations in human cells and found that the nucleoplasmic Fb...

A large number of biological factors that seem to have important prognostic significance have been identified in non-small cell lung cancers (NSCLCs). In the present study, we have characterized expression of cyclin D1 and cyclin E in a cohort of 217 resected NSCLCs from a single institution by immunohistochemistry to analyze their expression in relation to the growth fraction determined by Ki-...

Cyclin D1 and cyclin E are the mammalian G1 cydins that are both required and rate limiting for entry into S phase. Alterations in cell cycle regulators and subsequent deregulation of the cell cycle are frequently involved in tumorigenesis and/or tumor progression. We investigated the expression of cyclin D1 and cyclin E protein in 84 gastric carcinoma by immunohistochemical staining and also t...

The small ubiquitin-like modifier (SUMO) pathway is essential for the maintenance of genome stability. We investigated its possible involvement in the control of DNA replication during S phase by using the Xenopus cell-free system. Here we show that the SUMO pathway is critical to limit the number and, thus, the density of replication origins that are activated in early S phase. We identified c...

The p300 and CREB binding protein (CBP) transcriptional coactivators interact with a variety of transcription factors and regulate their activity. Among the interactions that have been described, the COOH-terminal region of p300 binds to cyclin E-cyclin-dependent kinase 2 (cyclin E-Cdk2) and TFIIB, as well as to the E1A gene products of adenovirus. Inhibition of Cdk activity by Cdk inhibitors, ...

We have found that CDK2 and cyclin E, but not cyclin A, accumulates within Cajal bodies (CBs) in a cell cycle-dependent fashion. In the absence of cyclin E, CDK2 is not enriched in the CB compartment, suggesting that the translocation of CDK2 to CBs is dependent on cyclin E. CDK2 and cyclin E could be recruited to CBs as a functional complex or CBs may serve as 'docking stations' for CDK2-cycli...