Mouse Anti-Estrone monoclonal antibody, clone E1

Because of its assumed role in breast cancer etiology, estrogen biotransformation (and interaction of compounds therewith) has been investigated in human biospecimens for decades. However, little attention has been paid to the well-known fact that large inter-individual variations exist in the proportion of breast glandular (GLT) and adipose (ADT) tissues and less to adequate tissue characterization. To assess the relevance of this, the present study compares estrogen biotransformation in GLT and ADT. GLT and ADT were isolated from 47 reduction mammoplasty specimens derived from women without breast cancer and were characterized histologically and by their percentages of oil. Levels of 12 unconjugated and five conjugated estrogens were analyzed by GC- and UHPLC-MS/MS, respectively, and levels of 27 transcripts encoding proteins involved in estrogen biotransformation by Taqman (R) probe-based PCR. Unexpectedly, one-third of specimens provided neat GLT only after cryosection. Whereas 17 beta-estradiol, estrone, and estrone-3-sulfate were detected in both tissues, estrone-3-glucuronide and 2-methoxy-estrone were detected predominately in GLT and ADT, respectively. Estrogen levels as well as ratios 17 beta-estradiol/estrone and estrone-3-sulfate/estrone differed significantly between GLT and ADT, yet less than between individuals. Furthermore, estrogen levels in GLT and ADT correlated significantly with each other. In contrast, levels of most transcripts encoding enzymes involved in biotransformation differed more than between individuals and did not correlate between ADT and GLT. Thus, mixed breast tissues (and plasma) will not provide meaningful information on local estrogen biotransformation (and interaction of compounds therewith) whereas relative changes in 17 beta-estradiol levels may be investigated in the more abundant ADT.

Qualitative and quantitative analysis of estrogens content in natural water is a difficult task. An important problem in the analysis of hormones in water is the quantitative determination of their individual species. Low detection limits and instability of estrogen derivatives are the main challenges. Magnetic molecularly imprinted polymers (mag-MIPs) in combination with Flowing Atmospheric-Pressure Afterglow Mass Spectrometry (FAPA-MS) were successfully used for analysis of estrogen hormones in water samples. The aim of the study was to obtain mag-MIPs selective to estrone (E1) and beta-estradiol (E2) for solid phase extraction and pre-concentration of estrogens. Due to their superior analyte binding properties at low concentrations (0.03 g in 1 g of polymer structure) and possibility of magnetic separation, mag-MIPs were proven to be very convenient and efficient adsorbent materials. In addition, MS analyses were performed using two ionization sources: ESI- and FAPA-MS. For both estrogens, LOD was significantly lower for FAPA-MS analysis (0.135 mu g L-1 for E1 and E2) than for ESI-MS analysis (27 mu g L-1 for E1 and 13.6 mu g L-1 for E2). The total estrogen concentration in the environmental water sample was determined as: cE1 = 0.271 mu g L-1 and cE2 = 0.275 mu g L-1.