Qian Xi, Zhao Feng-Qi
Laboratory of Lactation and Metabolic Physiology, Department of Animal and Veterinary Sciences, University of Vermont, Burlington, VT 05405, United States.
Laboratory of Lactation and Metabolic Physiology, Department of Animal and Veterinary Sciences, University of Vermont, Burlington, VT 05405, United States.
Biochim Biophys Acta. 2016 Jun;1859(6):812-9. doi: 10.1016/j.bbagrm.2016.03.015. Epub 2016 Mar 31.
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.
Oct-1和Oct-2在乳腺中的表达及其与八聚体基序的结合受发育和激素调控，这与乳蛋白的表达一致。这两种转录因子均持续结合于乳蛋白基因β-酪蛋白的近端启动子，并且可能在不同发育阶段通过与其他转录因子或辅因子相互作用而参与启动子活性的抑制或激活。特别地，促乳素和糖皮质激素可诱导Oct-1和Oct-2与β-酪蛋白启动子上的信号转导及转录激活因子5（STAT5）和糖皮质激素受体结合并相互作用，从而激活β-酪蛋白的表达。此外，越来越多的证据表明另一种Oct因子Oct-3/4参与乳腺肿瘤发生，这使得Oct-3/4成为乳腺癌一种新出现的预后标志物以及基因导向性治疗干预、预防和治疗乳腺癌的分子靶点。本文是由Dean Tantin博士编辑的名为《Oct转录因子家族》特刊的一部分。
