22 research outputs found
Measuring Seven Endogenous Ketolic Estrogens Simultaneously in Human Urine by High-Performance Liquid Chromatography-Mass Spectrometry
A rapid, sensitive, and specific high-performance liquid chromatography-electrospray ionization-multistage mass spectrometry (MS) method for measuring endogenous ketolic estrogen metabolites in human urine has been developed. The method requires a single hydrolysis/extraction/derivatization step and only 2.5 mL of urine, yet is able to simultaneously quantify estrone and its 2-methoxy and 2-, 4-, and 16alpha-hydroxy derivatives, 16-ketoestradiol, and 2-hydroxyestrone-3-methyl ether metabolites. The combination of a simple hydrazone derivatization step with multistage MS greatly enhances the sensitivity and specificity of the analysis of endogenous estrogen within human urine. Standard curves are linear over a 100-fold concentration range with linear regression correlation coefficients typically greater than 0.99. The lower limit of quantitation for each ketolic estrogen is 0.2 ng/2.5-mL urine sample (10 pg on column), with an accuracy of 93-103% and an overall precision, including the hydrolysis, extraction, and derivatization steps, of 1-13% relative standard derivation (RSD) for samples prepared concurrently and 8-16% RSD for samples prepared in separate batches. This method also allows for the identification of 2-hydroxyestrone-3-methyl ether in urine obtained from both pre- and postmenopausal women. This potentially protective estrogen metabolite has been previously reported only in the urine of pregnant women. Since individual patterns of estrogen metabolism may influence the risk of breast cancer, accurate and specific measurement of estrogen metabolites in biological matrixes will facilitate future research on breast cancer prevention, screening, and treatment
Recommended from our members
Safety and Efficacy Results of a Phase I, Open-Label Study of Concurrent and Delayed Nivolumab in Combination With nab-Paclitaxel and Carboplatin in Advanced Non-small Cell Lung Cancer.
Introduction: Multicenter, phase I study of concurrent and delayed nivolumab plus nab-paclitaxel/carboplatin in advanced non-small cell lung cancer (NSCLC). Methods: Chemotherapy-naive patients with advanced NSCLC (ineligible for potentially curative radiation or surgery) received nab-paclitaxel 100 mg/m2 (days 1, 8, 15) and carboplatin area under the curve 6 (day 1) intravenously every 21 days (first 4 cycles); nivolumab 5 mg/kg was administered intravenously (day 15) beginning in cycle 1 (concurrent) or cycle 3 (delayed) in separate cohorts and continued beyond the 4 chemotherapy cycles. The primary objective was to assess safety. Secondary objectives were to assess tolerability and explore antitumor activity. Results: All 32 patients received chemotherapy; 20 of 22 and 6 of 10 patients also received concurrent or delayed nivolumab, respectively. No dose-limiting toxicities were reported in the concurrent cohort; 1 dose-limiting toxicity was reported in the delayed cohort. In the concurrent cohort, 20 patients (91%) had ≥1 grade 3/4 treatment-emergent adverse event (TEAE), and 7 (32%) discontinued treatment due to TEAEs. In the delayed cohort, all patients had ≥1 grade 3/4 TEAE, and 2 (20%) discontinued due to TEAEs. The median progression-free and overall survival, respectively, were 10.5 and 29.3 months in the concurrent cohort and 4.1 and 8.2 months in the delayed cohort. Conclusions: The safety profile of the combination was consistent with that of individual agents and generally similar in the 2 cohorts. Efficacy outcomes in the concurrent cohort, but not in the delayed cohort, were encouraging and support the rationale for concurrent administration of nivolumab with nab-paclitaxel/carboplatin for the treatment of advanced NSCLC. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT02309177
Recommended from our members
Safety and Efficacy Results of a Phase I, Open-Label Study of Concurrent and Delayed Nivolumab in Combination With nab-Paclitaxel and Carboplatin in Advanced Non-small Cell Lung Cancer.
Introduction: Multicenter, phase I study of concurrent and delayed nivolumab plus nab-paclitaxel/carboplatin in advanced non-small cell lung cancer (NSCLC). Methods: Chemotherapy-naive patients with advanced NSCLC (ineligible for potentially curative radiation or surgery) received nab-paclitaxel 100 mg/m2 (days 1, 8, 15) and carboplatin area under the curve 6 (day 1) intravenously every 21 days (first 4 cycles); nivolumab 5 mg/kg was administered intravenously (day 15) beginning in cycle 1 (concurrent) or cycle 3 (delayed) in separate cohorts and continued beyond the 4 chemotherapy cycles. The primary objective was to assess safety. Secondary objectives were to assess tolerability and explore antitumor activity. Results: All 32 patients received chemotherapy; 20 of 22 and 6 of 10 patients also received concurrent or delayed nivolumab, respectively. No dose-limiting toxicities were reported in the concurrent cohort; 1 dose-limiting toxicity was reported in the delayed cohort. In the concurrent cohort, 20 patients (91%) had ≥1 grade 3/4 treatment-emergent adverse event (TEAE), and 7 (32%) discontinued treatment due to TEAEs. In the delayed cohort, all patients had ≥1 grade 3/4 TEAE, and 2 (20%) discontinued due to TEAEs. The median progression-free and overall survival, respectively, were 10.5 and 29.3 months in the concurrent cohort and 4.1 and 8.2 months in the delayed cohort. Conclusions: The safety profile of the combination was consistent with that of individual agents and generally similar in the 2 cohorts. Efficacy outcomes in the concurrent cohort, but not in the delayed cohort, were encouraging and support the rationale for concurrent administration of nivolumab with nab-paclitaxel/carboplatin for the treatment of advanced NSCLC. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT02309177