2 resultados para biological equivalent dose
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo
Resumo:
NEWEST (Neoadjuvant Endocrine Therapy for Women with Estrogen-Sensitive Tumors) is the first study to compare biological and clinical activity of fulvestrant 500 versus 250 mg in the neoadjuvant breast cancer setting. We hypothesized that fulvestrant 500 mg may be superior to 250 mg in blocking estrogen receptor (ER) signaling and growth. A multicenter, randomized, open-label, Phase II study was performed to compare fulvestrant 500 mg (500 mg/month plus 500 mg on day 14 of month 1) versus fulvestrant 250 mg/month for 16 weeks prior to surgery in postmenopausal women with ER+ locally advanced breast cancer. Core biopsies at baseline, week 4, and surgery were assessed for biomarker changes. Primary endpoint: change in Ki67 labeling index (LI) from baseline to week 4 determined by automated computer imaging system (ACIS). Secondary endpoints: ER protein expression and function; progesterone receptor (PgR) expression; tumor response; tolerability. ER and PgR were examined retrospectively using the H score method. A total of 211 patients were randomized (fulvestrant 500 mg: n = 109; 250 mg: n = 102). At week 4, fulvestrant 500 mg resulted in greater reduction of Ki67 LI and ER expression versus 250 mg (-78.8 vs. -47.4% [p < 0.0001] and -25.0 vs. -13.5% [p = 0.0002], respectively [ACIS]); PgR suppression was not significantly different (-22.7 vs. -17.6; p = 0.5677). However, H score detected even greater suppression of ER (-50.3 vs. -13.7%; p < 0.0001) and greater PgR suppression (-80.5 vs. -46.3%; p = 0.0018) for fulvestrant 500 versus 250 mg. At week 16, tumor response rates were 22.9 and 20.6% for fulvestrant 500 and 250 mg, respectively, with considerable decline in all markers by both ACIS and H score. No detrimental effects on endometrial thickness or bone markers and no new safety concerns were identified. This provides the first evidence of greater biological activity for fulvestrant 500 versus 250 mg in depleting ER expression, function, and growth.
Resumo:
Objective: To investigate, in male Wistar rats, the effects of long-term moderate red wine (RW) consumption (equivalent to similar to 0.15 mg% resveratrol RS), or RS in low (L, 0.15 mg%) or high (H, 400 mg%) doses in chow. Background: Both RW and RS exhibit cardioprotection. RS extends lifespan in obese rats. It is unclear whether RW consumption or low-dose RS delay vascular aging and prolong life span in the absence of overt risk factors. Methods: Endpoints were aerobic performance, exercise capacity, aging biomarkers (p53,p16,p21, telomere length and telomerase activity in aortic homogenates), vascular reactivity. Data were compared with controls (C) given regular chow. Results: Expressions of p53 decreased similar to 50% similar to with RW and LRS (p < 0.05 vs. C), p16 by similar to 29% with RW (p < 0.05 vs. C) and p21 was unaltered. RW and LRS increased telomere length >6.5-fold vs. C, and telomerase activity increased with LRS and HRS. All treatments increased aerobic capacity (C 32.5 +/- 1.2, RW 38.7 + 1.7, LRS 38.5 + 1.6, HRS 38.3 + 1.8 mlO2 min(-1) kg(-1)), and RW or LRS also improved time of exercise tolerance vs. C (p < 0.05). Endothelium-dependent relaxation improved with all treatments vs. C. Life span, however, was unaltered with each treatment vs. C = 673 +/- 30 days, p = NS. Conclusions: RW and LRS can preserve vascular function indexes in normal rats, although not extending life span. These effects were translated into better aerobic performance and exercise capacity. (c) 2012 Elsevier Ireland Ltd. All rights reserved.