| First Author | Ishii H | Year | 2005 |
| Journal | DNA Cell Biol | Volume | 24 |
| Issue | 3 | Pages | 173-9 |
| PubMed ID | 15767783 | Mgi Jnum | J:97842 |
| Mgi Id | MGI:3576519 | Doi | 10.1089/dna.2005.24.173 |
| Citation | Ishii H, et al. (2005) Differential Roles of E-Type Cyclins During Transformation of Murine E2F-1-Deficient Cells. DNA Cell Biol 24(3):173-9 |
| abstractText | Deregulation of retinoblastoma gene product (pRB) is a hallmark of cancer, which acts as a transcriptional repressor by targeting E2F transcription factors. A transcription factor E2F-1 is not only important for S phase entry of cell cycle, but also stimulates gene expression of pro-apoptotic molecules. To investigate roles of E2F-1 and its target genes in cellular transformation, we studied murine E2F-1-deficient embryonic fibroblasts. Compared with control wild-type cells, E2F-1-deficient cells at early passages were less sensitive to exposure to gamma-radiation and showed an increase of colony formation, while their growth was slow. After sequential passages, the growth of E2F-1-deficient cells reached closely to that of wild-type cells. Immunoblot study of E2F target genes showed that multiple passages of E2F-1-deficient cells resulted in preferential increase of cyclin E2 expression. Furthermore, carcinogenicity study using N-nitrosomethylbenzylamine demonstrated that, compared to wild-type mice, fore-stomach tumors in E2F-1-deficient mice expressed an increased amount of cyclin E2, but not cyclin E1. Taken together, the present study shows that differential roles of E-type cyclins are involved at least partially in the process of cellular transformation, supporting the concept of important roles of the E2F regulatory pathway in carcinogenesis. |
