Inverse correlation between estrogen receptor content and peroxidase activity in human mammary tumors

Identification and characterization of cytoplasmic estrogen receptor gave a biochemical basis for mammary hormone dependence, nevertheless, hormone receptor determination is not enough to allow us a complete prediction of hormone dependence thus search for new biochemical markers is a goal for experimental oncologists. In the present communication we report an inverse correlation between peroxidase activity in the human breast tumor tissue and the percentage of positive estrogen receptor in a group of 50 patients. Thus preliminary interpretation can be done about the actual role of this enzyme in relation to hormone dependence.