title: Regulatory roles of Oct proteins in the mammary gland.
abstract: The expression of Oct-1 and -2 and their binding to the octamer motif in the mammary gland are developmentally and hormonally regulated, consistent with the expression of milk proteins. Both of these transcription factors constitutively bind to the proximal promoter of the milk protein gene β-casein and might be involved in the inhibition or activation of promoter activity via interactions with other transcription factors or cofactors at different developmental stages. In particular, the lactogenic hormone prolactin and glucocorticoids induce Oct-1 and Oct-2 binding and interaction with both the signal transducer and activator of transcription 5 (STAT5) and the glucocorticoid receptor on the β-casein promoter to activate β-casein expression. In addition, increasing evidence has shown the involvement of another Oct factor, Oct-3/4, in mammary tumorigenesis, making Oct-3/4 an emerging prognostic marker of breast cancer and a molecular target for the gene-directed therapeutic intervention, prevention and treatment of breast cancer. This article is part of a Special Issue entitled: The Oct Transcription Factor Family, edited by Dr. Dean Tantin.
authors.affiliation: Laboratory of Lactation and Metabolic Physiology, Department of Animal and Veterinary Sciences, University of Vermont, Burlington, VT 05405, United States.
authors.forename: Xi
authors.initials: X
authors.lastname: Qian
authors.affiliation: Laboratory of Lactation and Metabolic Physiology, Department of Animal and Veterinary Sciences, University of Vermont, Burlington, VT 05405, United States. Electronic address: fzhao@uvm.edu.
authors.forename: Feng-Qi
authors.initials: FQ
authors.lastname: Zhao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D063646:Carcinogenesis / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007774:Lactation / Q000235:genetics; D042361:Mammary Glands, Human / Q000378:metabolism / Q000473:pathology; D008969:Molecular Sequence Data; D050811:Octamer Transcription Factor-1 / Q000235:genetics* / Q000378:metabolism; D050813:Octamer Transcription Factor-2 / Q000235:genetics* / Q000378:metabolism; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D015533:Transcriptional Activation
chemical_list: D050811:Octamer Transcription Factor-1; D050813:Octamer Transcription Factor-2; C494165:POU2F1 protein, human; D020033:Protein Isoforms
keywords: Breast cancer; Mammary gland; Milk protein; Oct protein; Transcriptional regulation