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Atypical E2Fs: new players in the E2F transcription factor family.

ABSTRACT: As major regulators of the cell cycle, apoptosis and differentiation, E2F transcription factors have been studied extensively in a broad range of organisms. The recent identification of atypical E2F family members further expands our structural, functional and molecular view of the cellular E2F activity. Unlike other family members, atypical E2Fs have a duplicated DNA-binding domain and control gene expression without heterodimerization with dimerization partner proteins. Recently, knockout strategies in plants and mammals have pinpointed that atypical E2Fs have a crucial role in plant cell size control, endocycle regulation, proliferation and apoptotic response upon DNA stress. Their position at the crossroads of proliferation and DNA stress response marks these novel E2F proteins as interesting study objects in the field of tumor biology.

SUBMITTER: Lammens T

PROVIDER: S-EPMC2808192 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature

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Atypical E2Fs: new players in the E2F transcription factor family.

Lammens Tim T Li Jing J Leone Gustavo G De Veylder Lieven L

Trends in cell biology 20090207 3

As major regulators of the cell cycle, apoptosis and differentiation, E2F transcription factors have been studied extensively in a broad range of organisms. The recent identification of atypical E2F family members further expands our structural, functional and molecular view of the cellular E2F activity. Unlike other family members, atypical E2Fs have a duplicated DNA-binding domain and control gene expression without heterodimerization with dimerization partner proteins. Recently, knockout stra ...[more]

PMID: 19201609

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Atypical E2Fs inhibit tumor angiogenesis.

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E2F-5, a new E2F family member that interacts with p130 in vivo.

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| S-EPMC3771987 | biostudies-literature

Prognostic Value of E2F Transcription Factor Expression in Pancreatic Adenocarcinoma.

Project description:BACKGROUND Pancreatic adenocarcinoma (PAAD) is one of the deadliest types of cancer. In the early stages, patients often have atypical symptoms, making diagnosis difficult. The prognosis of diagnosed patients is very poor and treating PAAD is challenging. Therefore, determining reliable risk factors related to PAAD development is critical for improving patient prognosis. E2F family transcription factors (TFs) are essential regulators of DNA synthesis and cell cycle progression in eukaryotic cells, and they have been identified as prognostic biomarkers associated with multiple cancer types. However, further research is necessary to establish the prognostic relevance of these TFs in PAAD patients. MATERIAL AND METHODS We assessed PAAD patient transcriptional and outcome data using the TIMER, ONCOMINE, STRING, GEPIA, cBioPortal, Kaplan-Meier Plotter, GSCALite, and starBase databases. RESULTS PAAD tumor tissues exhibited increased expression of E2F1/3/5/7/8 relative to that in normal tissues, while the expression of E2F2/3/6/8 was associated with a more advanced tumor stage. Survival analyses indicated that PAAD patients expressing higher levels of E2F1/2/3/7/8 exhibited shorter overall survival (OS) and disease-free survival (DFS) than patients expressing lower levels of these TFs. In addition, E2F4 and E2F6 overexpression was associated with poorer DFS and OS, respectively. We also found that the expression of E2Fs was significantly correlated with immune infiltrates, including CD8+ T cells, CD4+ T cells, B cells, dendritic cells, neutrophils, and macrophages. CONCLUSIONS Our study may provide new insights into the optimal choice of immunotherapy and promising novel targets for therapeutic intervention in PAAD patients.

| S-EPMC8611937 | biostudies-literature

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