CHAPTER 5 Estrogen , MSI and Lynch Syndrome-Associated Tumors

Estrogens play a major role in the biology of hormonally responsive tissues but also in the normal physiology of various non-typical hormone responsive tissues. In disease, estrogens have been associated with tumor development, in particular with tumors such as breast, endometrium, ovary and prostate. In this paper we will review the molecular mechanisms by which estrogens are involved in cancer development, with a special focus in Lynch syndromerelated tumors. Further, we discuss the role estrogens might have on cell proliferation and apoptosis, how estrogens metabolites can induce DNA damage, and we discuss a possible connection between estrogens and changes in DNA (hypoand hyper-) methylation. In this review we will also address the protective effect that high levels of estrogen have in MMRrelated neoplasias.