查看文章

The role of estrogen blockadein the treatment of certain neoplastic disorders has been of wide interest for a number of years. It has long been known that specific tumors, particularly breast cancer in women, can grow more rapidly in proportion to the surrounding levels of estrogen. 1 Recent advances in the areas of molecular and cellular biology have led to a more detailed understanding of es-trogen action. The estrogen receptor gene has been cloned, sequenced, and expressed. 2 The estrogen receptor protein seems to be composed of two nonoverlappingfunctional domains: the first domain has a high affinity for estrogen and the second has a high affinity for DNA. Upon binding of estrogen to the first domain, a conformational change is apparently triggered in the second domain, allowing it to productively interact with a specific sequence of DNA nucleotides known as a transcriptional enhancer region. The result …