Mitogen-regulated protein/proliferin mRNA induction following single applications of tumor promoters to murine skin.
Mitogen-regulated protein/proliferin (mrp/plf) gene family transcripts rise in abundance as a response to diverse chemical and physical agents that promote morphological transformation in the murine C3H/10T1/2 cultured cell model of multi-step carcinogenesis. To determine if proliferin genes respond to tumor promoters in vivo, RNA was extracted from the whole skin of SENCAR mice after single applications of 2 or 20 microg 12-O-tetradecanoylphorbol-13-acetate (TPA); 3.2 or 32 nmole), 20 or 40 mg benzoyl peroxide (BPO; 83, 165 micromole), or acetone vehicle alone (2.72 mmole). RNA samples were prepared from treated skin areas, 2-48 h after painting. Mrp/plf-mRNA was not detected in Northern blot hybridizations, but large increases in mRNAs for ornithine decarboxylase gene and mRNA (odc), v-jun oncogene-related transcription factor gene and mRNA (junB), egr1 (early growth response protein gene and mRNA) were measured relative to beta 2 microglobulin gene and mRNA (b2m) mRNA in response to TPA. BPO induced small relative changes in these mRNAs. Reverse transcriptase (RT)-polymerase chain reactions (PCR) detected fully-processed MRP/plf-mRNA 16-48 h after TPA treatments in five of six animals, and in three of six BPO-treated animals. The MRP/plf-mRNA species expressed in the skin were predominantly plf1 and mrp3 as determined by gene-specific restriction enzyme sites within the RT-PCR products. Expression was either undetectable or found at low levels in acetone-painted controls and was not detected during the anagen phase of the normal hair growth cycle in unpainted animals. These results demonstrate that mrp/plf-mRNA is differentially expressed in murine skin in response to mechanistically distinct tumor promoters and has potential utility as a short-term biomarker for tumor promoting effects in chemical carcinogenesis.
Parfett
Craig L J
CL
Mutagenesis Section, Healthy Environments and Consumer Safety Branch, Health Canada, Environmental Health Centre, Tunney's Pasture, Ottawa, Ontario, Canada.
D000096:Acetone; D000818:Animals; D001585:Benzoyl Peroxide / Q000633:toxicity; D015152:Blotting, Northern; D002273:Carcinogens / Q000633:toxicity*; D002460:Cell Line; D020869:Gene Expression Profiling / Q000379:methods; D006023:Glycoproteins / Q000235:genetics*; D036341:Intercellular Signaling Peptides and Proteins; D007700:Kinetics; D051379:Mice; D008809:Mice, Inbred C3H; D011388:Prolactin; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics*; D012867:Skin / Q000187:drug effects / Q000473:pathology*; D013755:Tetradecanoylphorbol Acetate / Q000633:toxicity; D014158:Transcription, Genetic / Q000187:drug effects
D002273:Carcinogens; D006023:Glycoproteins; D036341:Intercellular Signaling Peptides and Proteins; C000634106:Prl2c2 protein, mouse; D012333:RNA, Messenger; D000096:Acetone; D011388:Prolactin; D013755:Tetradecanoylphorbol Acetate; D001585:Benzoyl Peroxide