title: Truncation of inhibitor of growth family protein 5 effectively induces senescence, but not apoptosis in human tongue squamous cell carcinoma cell line.
abstract: In these studies, inhibitor of growth protein 5 (ING5) and various fragments of it were overexpressed in the human tongue squamous cell carcinoma cell line, HSC-3. The roles of ING5 in HSC-3 cells were then identified in vitro. Our results indicate that intact ING5 can inhibit proliferation and induce apoptosis in HSC-3 cells. Moreover, two truncated fragments of ING5 (aa 1-184 and aa 107-226) can induce cellular senescence. To analyze the signaling pathway involved, western blotting was performed. In these assays, two truncated fragments of ING5 were found to inhibit the cyclin E and CDK2 expression. These results are consistent with the S phase arrest observed with the overexpression of truncated ING5. However, the mechanisms of ING5-induced cellular senescence remain unclear, and extensive investigations are required in future studies.
authors.affiliation: Department of Orthodontics, School of Stomatology, China Medical University, Shenyang, Liaoning, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Qi
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D045744:Cell Line, Tumor; D016922:Cellular Senescence / Q000187:drug effects*; D019927:Cyclin E / Q000037:antagonists & inhibitors / Q000235:genetics; D051357:Cyclin-Dependent Kinase 2 / Q000037:antagonists & inhibitors / Q000235:genetics; D006801:Humans; D010446:Peptide Fragments / Q000494:pharmacology*; D014062:Tongue Neoplasms / Q000473:pathology*; D014157:Transcription Factors / Q000494:pharmacology*; D025521:Tumor Suppressor Proteins / Q000494:pharmacology*
chemical_list: D019927:Cyclin E; C508131:ING5 protein, human; D010446:Peptide Fragments; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; C495894:CDK2 protein, human; D051357:Cyclin-Dependent Kinase 2