title: Atmospheric pressure photoionization tandem mass spectrometry of androgens in prostate cancer.
abstract: Androgen deprivation therapy is the most common treatment option for advanced prostate cancer. Almost all prostate cancers recur during androgen deprivation therapy, and new evidence suggests that androgen receptor activation persists despite castrate levels of circulating androgens. Quantitation of tissue levels of androgens is critical to understanding the mechanism of recurrence of prostate cancer during androgen deprivation therapy. A liquid chromatography atmospheric pressure photoionization tandem mass spectrometric method was developed for quantitation of tissue levels of androgens. Quantitation of the saturated keto-steroids dihydrotestosterone and 5-alpha-androstanedione required detection of a novel parent ion, [M + 15](+). The nature of this parent ion was explored, and the method was applied to prostate tissue and cell culture with comparison to results achieved using electrospray ionization.
authors.affiliation: National Institute of Environmental Health Sciences/National Institutes of Health/Department of Health and Human Services, Research Triangle Park, North Carolina 27709-2233, USA.
authors.forename: Fred Bjørn
authors.initials: FB
authors.lastname: Lih
authors.forename: Mark A
authors.initials: MA
authors.lastname: Titus
authors.forename: James L
authors.initials: JL
authors.lastname: Mohler
authors.forename: Kenneth B
authors.initials: KB
authors.lastname: Tomer
mesh_terms: D000728:Androgens / Q000032:analysis*; D001274:Atmospheric Pressure; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D013196:Dihydrotestosterone / Q000032:analysis; D005043:Etiocholanolone / Q000031:analogs & derivatives / Q000032:analysis; D006801:Humans; D008297:Male; D011471:Prostatic Neoplasms / Q000628:therapy*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000728:Androgens; D013196:Dihydrotestosterone; C006576:androstane-3,17-dione; D005043:Etiocholanolone