title: Treatment with the cancer drugs decitabine and doxorubicin induces human skin keratinocytes to express Oct4 and the OCT4 regulator mir-145.
abstract: Previously, we showed that transient transfection with OCT4 not only produced high expression of Oct4 in skin keratinocytes, but also caused a generalized demethylation of keratinocyte DNA. We hypothesized that DNA demethylation alone might allow expression of endogenous OCT4. Here, we report that treatment with the cancer drug decitabine results in generalized DNA demethylation in skin keratinocytes, and by 48 h after treatment, 96% of keratinocytes show expression of the endogenous Oct4 protein and the OCT4 repressor mir-145. This is true for keratinocytes only, as skin fibroblasts treated similarly show no OCT4 or mir-145 expression. Decitabine-treated keratinocytes also show increased mir-302c and proliferation similar to other Oct4(+) cells. Treatment with doxorubicin, another cancer drug, induces expression of mir-145 only in cells that already express OCT4, suggesting that Oct4 regulates its own repressor. Co-treatment with decitabine and doxorubicin results first in increased OCT4 and mir-145, then a decrease in both, suggesting that OCT4 and mir-145 regulate each other. The novel strategy presented here provides a regulatable system to produce Oct4(+) cells for transformation studies and provides a unique method to study the effects of endogenous Oct4 in cancer cells and the surrounding somatic cells.
authors.affiliation: Department of Anatomy and Cell Biology, The University of Iowa Carver College of Medicine, Iowa City, Iowa, USA.
authors.forename: Sathivel
authors.initials: S
authors.lastname: Chinnathambi
authors.forename: Susan
authors.initials: S
authors.lastname: Wiechert
authors.forename: Ann
authors.initials: A
authors.lastname: Tomanek-Chalkley
authors.forename: Michael C
authors.initials: MC
authors.lastname: Winter
authors.forename: Jackie R
authors.initials: JR
authors.lastname: Bickenbach
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology; D001374:Azacitidine / Q000031:analogs & derivatives* / Q000494:pharmacology; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D019175:DNA Methylation; D000077209:Decitabine; D004317:Doxorubicin / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D050814:Octamer Transcription Factor-3 / Q000235:genetics / Q000378:metabolism*; D012867:Skin / Q000166:cytology / Q000187:drug effects / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; C541010:MIRN145 microRNA, human; C532169:MIRN302A microRNA, human; D035683:MicroRNAs; D050814:Octamer Transcription Factor-3; C494173:POU5F1 protein, human; D000077209:Decitabine; D004317:Doxorubicin; D001374:Azacitidine