title: Analysis of estrogens and androgens in postmenopausal serum and plasma by liquid chromatography-mass spectrometry.
abstract: Liquid chromatography-selected reaction monitoring/mass spectrometry-based methodology has evolved to the point where accurate analyses of trace levels of estrogens and androgens in postmenopausal serum and plasma can be accomplished with high precision and accuracy. A suite of derivatization procedures has been developed, which together with modern mass spectrometry instrumentation provide investigators with robust and sensitive methodology. Pre-ionized derivatives are proving to be useful as they are not subject to suppression of the electrospray signal. Postmenopausal women with elevated plasma or serum estrogens are thought to be at increased risk for breast and endometrial cancer. Therefore, significant advances in risk assessment should be possible now that reliable methodology is available. It is also possible to conduct analyses of multiple estrogens in plasma or serum. Laboratories that are currently employing liquid chromatography/mass spectrometry methodology can now readily implement this strategy. This will help conserve important plasma and serum samples available in Biobanks, as it will be possible to conduct high sensitivity analyses using low initial sample volumes. Reported levels of both conjugated and non-conjugated estrogen metabolites are close to the limits of sensitivity of many assays to date, urging caution in the interpretation of these low values. The analysis of serum androgen precursors in postmenopausal women has not been conducted routinely in the past using liquid chromatography/mass spectrometry methodology. Integration of serum androgen levels into the panel of metabolites analyzed could provide additional information for assessing cancer risk and should be included in the future.
authors.affiliation: Centers of Excellence in Environmental Toxicology and Cancer Pharmacology, Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-4863, USA; Department of Pharmacology and Toxicology, Beijing Institute of Radiation Medicine, Beijing 100850, China.
authors.forename: Qingqing
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Centers of Excellence in Environmental Toxicology and Cancer Pharmacology, Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-4863, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: Bottalico
authors.affiliation: Centers of Excellence in Environmental Toxicology and Cancer Pharmacology, Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-4863, USA.
authors.forename: Clementina
authors.initials: C
authors.lastname: Mesaros
authors.affiliation: Centers of Excellence in Environmental Toxicology and Cancer Pharmacology, Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-4863, USA. Electronic address: ianblair@mail.med.upenn.edu.
authors.forename: Ian A
authors.initials: IA
authors.lastname: Blair
mesh_terms: D000728:Androgens / Q000097:blood*; D002853:Chromatography, Liquid / Q000379:methods*; D045166:Estradiol Congeners / Q000097:blood / Q000378:metabolism; D004967:Estrogens / Q000097:blood* / Q000378:metabolism; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006801:Humans; D057230:Limit of Detection; D017698:Postmenopause / Q000097:blood*; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000295:instrumentation / Q000379:methods*
chemical_list: D000728:Androgens; D045166:Estradiol Congeners; D004967:Estrogens
keywords: Androgens; Estrogens; Liquid chromatography/mass spectrometry; Pre-ionized derivatives; Stable isotope dilution