Tamoxifen blocks chloride channels. A possible mechanism for cataract formation.

• DOI: 10.1172/jci117514
• Publication Date: 2008-02-29T14:48:05Z
• Authors: J J Zhang; T J Jacob; M A Valverde; S P Hardy; G M Mintenig; F V Sepúlveda; D R Gill; S C Hyde; A E Trezise; C F Higgins
• Keywords: Antiestrogen

Tamoxifen is an antiestrogen frequently used in the treatment of breast cancer and currently being assessed as a prophylactic for those at high risk developing tumors. We have found that tamoxifen its derivatives are high-affinity blockers specific chloride channels. This blockade appears to be independent interaction with estrogen receptor therefore reflects alternative cellular target. One clinical side effects impaired vision cataract. Chloride channels lens eye were shown essential maintaining normal hydration transmittance. These blocked by and, organ culture, led opacity associated cataracts clinically relevant concentrations. data suggest molecular mechanism which can cause cataract formation implications use related antiestrogens.