PET Imaging of Estrogen Metabolism in Breast Cancer
Abstract
It is well known that many breast tumors associate with estrogen and the presence of catecholestrogens in breast tumors cause changes in the DNA which may lead to uncontrolled cell growth. Catecholestrogens are broken down by an enzyme called catechol-O- methyltransferase (COMT). COMT is known to be elevated in malignant breast tumors, and abnormal COMT genetics have recently been found in individuals with breast cancer. We have developed LSFro4I%o96o, the first radiotracer for visualizing COMT with positron emission tomography (PET). The hypothesis that IsFro41%o96o can map COMT in vivo was demonstrated in baboon and mouse. A complementary ex vivo approach in which we correlated the radiotracer uptake with COMT activities in rodents further demonstrated the ability of'%Fro4l-0960 in mapping COMT activity in vivo. Recently, we have adapted our COMT enzyme assay method and performed studies in breast tumor tissue samples from cancer patients undergoing surgery. COMT activities in normal and abnormal human breast tissues from the same patient were compared. Though COMT activities varied among subjects, preliminary results showed elevated COMT activities in the breast tumor tissues of all patients studied; the difference can be as high as 26 fold increase. This novel approach to an extremely important medical problem goes beyond diagnosis in that it seeks to delineate the fundamental biochemical properties and molecular signatures of tumor cells. PET imaging studies on breast cancer patients are underway.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 2000
- Accession Number
- ADA392378
Entities
People
- Yu-shin Ding
Organizations
- Brookhaven National Laboratory