title: Contrasting effects of Krüppel-like factor 4 on X-ray-induced double-strand and single-strand DNA breaks in mouse astrocytes.
abstract: Astrocytes, the most common cell type in the brain, play a principal role in the repair of damaged brain tissues during external radiotherapy of brain tumours. As a downstream gene of p53, the effects of Krüppel-like factor 4 (KLF4) in response to X-ray-induced DNA damage in astrocytes are unclear. In the present study, KLF4 expression was upregulated after the exposure of astrocytes isolated from the murine brain. Inhibition of KLF4 expression using lentiviral transduction produced less double-strand DNA breaks (DSB) determined by a neutral comet assay and flow cytometric analysis of phosphorylated histone family 2A variant and more single-strand DNA breaks (SSB) determined by a basic comet assay when the astrocytes were exposed to 4 Gy of X-ray radiation. These data suggest that radiation exposure of the tissues around brain tumour during radiation therapy causes KLF4 overexpression in astrocytes, which induces more DSB and reduces SSB. This causes the adverse effects of radiation therapy in the treatment of brain tumours.
authors.affiliation: The second affiliated hospital of Soochow University, Suzhou, China.
authors.forename: Ji
authors.initials: J
authors.lastname: Zhang
authors.forename: Fengmei
authors.initials: F
authors.lastname: Cui
authors.forename: Lei
authors.initials: L
authors.lastname: Li
authors.forename: Jiangtao
authors.initials: J
authors.lastname: Yang
authors.forename: Liyuan
authors.initials: L
authors.lastname: Zhang
authors.forename: Qiu
authors.initials: Q
authors.lastname: Chen
authors.forename: Ye
authors.initials: Y
authors.lastname: Tian
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000378:metabolism / Q000528:radiation effects*; D053903:DNA Breaks, Double-Stranded / Q000528:radiation effects*; D053904:DNA Breaks, Single-Stranded / Q000528:radiation effects; D053938:DNA Fragmentation / Q000528:radiation effects; D006657:Histones / Q000378:metabolism; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL
chemical_list: D006657:Histones; C000715468:Klf4 protein, mouse; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors
keywords: KLF4; astrocytes; double-strand DNA breaks; single-strand DNA breaks