title: Hyperthermia-induced micronucleus formation in a human keratinocyte cell line.
abstract: Elevated temperature can cause biological effects in vitro and in vivo. Many studies on effects of hypo- and hyperthermia have been conducted, but only few studies systematically investigated the formation of genomic damage in the micronucleus test in human cells in vitro as a consequence of different temperatures. In the present study, HaCaT human keratinocytes were exposed to different temperatures from 37°C to 42°C for 24h in a regular cell culture incubator. Micronucleus frequency as a marker of genomic damage was elevated in a temperature-dependent and statistically significant manner. Apoptosis occurred at temperatures of 39°C or higher. Cell proliferation was unaffected up to 40°C and decreased at 41°C and 42°C. Expression of the heat shock protein Hsp70 was elevated, particularly at temperatures of 40°C and higher. These findings are in agreement with several in vivo studies and some in vitro studies looking at single, specific temperatures, but a systematically investigated temperature-dependent increase of genomic damage in human keratinocytes in vitro is demonstrated for the first time here.
authors.affiliation: Universität Würzburg, Institut für Pharmakologie und Toxikologie, Würzburg, Germany.
authors.forename: Henning
authors.initials: H
authors.lastname: Hintzsche
authors.forename: Thorsten
authors.initials: T
authors.lastname: Riese
authors.forename: Helga
authors.initials: H
authors.lastname: Stopper
mesh_terms: D017209:Apoptosis; D002460:Cell Line; D004249:DNA Damage; D018840:HSP70 Heat-Shock Proteins / Q000096:biosynthesis; D006358:Hot Temperature; D006801:Humans; D006979:Hyperthermia, Induced; D015603:Keratinocytes / Q000378:metabolism; D048629:Micronuclei, Chromosome-Defective
chemical_list: D018840:HSP70 Heat-Shock Proteins