Laboratory of Molecular Technology, National Cancer Institute-Frederick, Frederick, MD 21702, USA.
Proc Natl Acad Sci U S A. 2010 Feb 16;107(7):3001-5. doi: 10.1073/pnas.0906067107. Epub 2010 Jan 26.
Recent genomewide association studies have found multiple genetic variants on chromosome 8q24 that are significantly associated with an increased susceptibility to prostate, colorectal, and breast cancer. These risk loci are located in a "gene desert," a few hundred kilobases telomeric to the Myc gene. To date, the biological mechanism(s) underlying these associations remain unclear. It has been speculated that these 8q24 genetic variant(s) might affect Myc expression by altering its regulation or amplification status. Here, we show that multiple enhancer elements are present within this region and that they can regulate transcription of Myc. We also demonstrate that one such enhancer element physically interacts with the Myc promoter via transcription factor Tcf-4 binding and acts in an allele specific manner to regulate Myc expression.
最近的全基因组关联研究发现,8q24 染色体上的多个遗传变异与前列腺癌、结直肠癌和乳腺癌的易感性增加显著相关。这些风险位点位于“基因荒漠”中,距 Myc 基因几百千碱基对的端粒位置。迄今为止,这些关联的生物学机制尚不清楚。据推测,这些 8q24 遗传变异可能通过改变 Myc 的调控或扩增状态来影响 Myc 的表达。在这里,我们表明该区域内存在多个增强子元件,它们可以调节 Myc 的转录。我们还证明,这样一个增强子元件通过转录因子 Tcf-4 结合与 Myc 启动子物理相互作用,并以等位基因特异性方式作用以调节 Myc 的表达。