instruction:
In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
question:
Context: Progress in the management of patients with medically intractable epilepsy is impeded because we do not fully understand why pharmacoresistance happens and how it can be predicted. The presence of multiple seizures prior to medical treatment has been suggested as a potential predictor of poor outcome. In the present study, we used an animal model of temporal lobe epilepsy to investigate whether pharmacoresistant rats differ in seizure frequency from pharmacoresponsive animals.', 'Epilepsy with spontaneous recurrent seizures (SRS) was induced by status epilepticus. Frequency of SRS was determined by video/EEG (electroencephalography) monitoring in a total of 33 epileptic rats before onset of treatment with phenobarbital (PB).', 'Thirteen (39%) rats did not respond to treatment with PB. Before treatment with PB, average seizure frequency in PB nonresponders was significantly higher than seizure frequency in responders, which, however, was due to six nonresponders that exhibited > 3 seizures per day. Such high seizure frequency was not observed in responders, demonstrating that high seizure frequency predicts pharmacoresistance in this model, but does not occur in all nonresponders.\Question: Is high seizure frequency prior to antiepileptic treatment a predictor of pharmacoresistant epilepsy in a rat model of temporal lobe epilepsy?
answer:
The data from this study are in line with clinical experience that the frequency of seizures in the early phase of epilepsy is a dominant risk factor that predicts refractoriness. However, resistance to treatment also occurred in rats that did not differ in seizure frequency from responders, indicating that disease severity alone is not sufficient to explain antiepileptic drug (AED) resistance. These data provide further evidence that epilepsy models are useful in the search for predictors and mechanisms of pharmacoresistance.


question:
Context: Breast cancer is a hormone-dependent cancer, and the presence of estrogen receptor alpha (ER-alpha) in tumors is used clinically to predict the likelihood of response to hormonal therapies. The clinical value of the second recently identified ER isoform, called ER-beta, is less clear, and there is currently conflicting data concerning its potential role as a prognostic or predictive factor.', 'To assess whether ER-beta expression is associated with clinical outcome, protein levels were measured by immunoblot analysis of a retrospective bank of tumor cell lysates from 305 axillary node-positive patients. A total of 119 received no adjuvant therapy, and 186 were treated with tamoxifen only. The median follow-up time was 65 months. Univariate and multivariate Cox regression modeling was done to assess the prognostic and predictive significance of ER-beta expression.', 'Expression of ER-beta protein did not correlate significantly with any other clinical variables, including ER and progesterone levels (as measured ligand binding assay), tumor size, age, or axillary nodal status. In the untreated population, those patients whose tumors who expressed both receptor isoforms exhibited the most favorable outcome as compared with those patients who had lost ER-alpha expression. However, there was no association between ER-beta levels alone and either disease-free or overall survival in the untreated patient population. In contrast, in both univariate and multivariate analyses, high levels of ER-beta predicted an improved disease-free and overall survival in patients treated with adjuvant tamoxifen therapy.\Question: Do low levels of estrogen receptor beta protein predict resistance to tamoxifen therapy in breast cancer?
answer:
These findings provide evidence that ER-beta may be an independent predictor of response to tamoxifen in breast cancer. Furthermore, these results suggest that ER-beta may influence tumor progression in ways different from those mediated by the ER-alpha isoform.


question:
Context: Fulvestrant is a pure anti-estrogen hormoal agent formally lacking any estrogen-agonist activity. We analyze the effect(s) of fulvestrant treatment on estrogen target systems in hormoe-sensitive advanced breast cancer patients.', 'Patients received a median of five fulvestrant injections (range 3-19). We observed a partial response in one patient, disease stability in 21 and disease progression in 29 patients with a clinical benefit of 43.2% and a median time to progression of 5 [range 3-20] mo. Total cholesterol levels significantly decreased during treatment (219.8 +/- 45.3 vs. 201.4 +/- 42.1 mg/dl; p = 0.0054) together with LDL-cholesterol (129.7 +/- 41.39 vs. 112.3 +/- 37.1 mg/dl; p = 0.018). HDL-cholesterol and triglycerides did not show significant changes. Reduction of total and LDL-cholesterol was independent from last hormoal treatment or treatment duration. All coagulation indices and mean endometrial mucosa thickness value did not vary.', 'Fifty-one patients [median age 65 (range 48-82) y] were enrolled. All patients received previous hormoal treatments, with 90.2% receiving > or =2 courses. Last hormoal treatment was exemestane, letrozole, anastrozole and other in 30-10-7-4/51 patients respectively. Median withdrawal time was 18 d (range 3-1456). Complete fasting lipid blood profile and coagulation indices were assessed before fulvestrant administration, every 3 mo and at discontinuation time. Endometrial mucosa thickness was evaluated before fulvestrant administration and at end-study time.\Question: Is fulvestrant treatment associated with cholesterol plasma level reduction in hormone-receptor-positive metastatic breast cancer patients?
answer:

We observed a lipid lowering effect of fulvestrant possibly related to an influence on lipid metabolism by a mechanism in which a role could be played by progesterone receptor.