title: Lentivirus-mediated RNA interference of E2F-1 suppresses Tca8113 cell             proliferation.
abstract: In most types of human cancer, inactivation of pRb/E2F complexes occurs, and released E2Fs initiate transcription of genes required for cell cycle progression. Evidence reveals that phosphorylated pRb deregulates E2F-1, and the levels of E2F-1 expression can accurately predict prognosis of oral squamous cell carcinoma (OSCC). Paradoxically, numerous reports indicate that E2F-1 is also capable of inducing apoptosis under certain cellular circumstances. In the present study, lentivirus-mediated shRNA was used to downregulate endogenous E2F-1 expression in order to study the function of E2F-1 in the pRb/E2F-1 pathway in the OSCC cell line Tca8113, and to investigate the alteration of Tca8113 cells in proliferation and apoptosis. The data from real-time quantitative RT-PCR and Western blot analysis showed that E2F-1-shRNA led to the inhibition of endogenous E2F-1 mRNA and protein expression, and E2F-1 may be associated with proliferation and apoptosis pathways. Growth kinetics data showed that Tca8113-E2F-1-shRNA cells presented more active proliferation properties than Tca8113-NC cells, and flow cytometry data demonstrated that the percentages of cells in the G1 phase, G2 phase and undergoing apoptosis differed between groups. In conclusion, silencing of E2F-1 inhibits proliferation and induces apoptosis. E2F-1 may also be involved in multi-level regulation networks; therefore, its role in OSCC requires further clarification.
authors.affiliation: Institute of Dental Research, Nanjing Medical University, Nanjing, Jiangsu 210029, PR China.
authors.forename: Hua
authors.initials: H
authors.lastname: Yuan
authors.forename: Fei
authors.initials: F
authors.lastname: Jiang
authors.forename: Ruixia
authors.initials: R
authors.lastname: Wang
authors.forename: Ming
authors.initials: M
authors.lastname: Shen
authors.forename: Ning
authors.initials: N
authors.lastname: Chen
mesh_terms: D017209:Apoptosis; D002294:Carcinoma, Squamous Cell / Q000378:metabolism / Q000473:pathology; D018797:Cell Cycle Proteins; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D050687:E2F1 Transcription Factor / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D016193:G1 Phase; D016195:G2 Phase; D006801:Humans; D016086:Lentivirus / Q000235:genetics*; D009062:Mouth Neoplasms / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering; D012097:Repressor Proteins / Q000378:metabolism; D014162:Transfection
chemical_list: D018797:Cell Cycle Proteins; D050687:E2F1 Transcription Factor; C493753:E2F1 protein, human; C416925:EID1 protein, human; D009687:Nuclear Proteins; D034741:RNA, Small Interfering; D012097:Repressor Proteins