Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Ex Input:
Context: With the advent of new and more efficient anti-androgen drugs targeting androgen receptor (AR) in breast cancer (BC) is becoming an increasingly important area of investigation. This would potentially be most useful in triple negative BC (TNBC), where better therapies are still needed. The assessment of AR status is generally performed on the primary tumor even if the tumor has already metastasized. Very little is known regarding discrepancies of AR status during tumor progression. To determine the prevalence of AR positivity, with emphasis on TNBCs, and to investigate AR status during tumor progression, we evaluated a large series of primary BCs and matching metastases and recurrences.', 'AR status was performed on 356 primary BCs, 135 matching metastases, and 12 recurrences using a next-generation Tissue Microarray (ngTMA). A commercially available AR antibody was used to determine AR-status by immunohistochemistry. AR positivity was defined as any nuclear staining in tumor cells 1 %. AR expression was correlated with pathological tumor features of the primary tumor. Additionally, the concordance rate of AR expression between the different tumor sites was determined.', 'AR status was positive in: 87 % (307/353) of primary tumors, 86.1 % (105/122) of metastases, and in 66.7 % (8/12) of recurrences. TNBC tested positive in 11.4 %, (4/35) of BCs. A discrepant result was seen in 4.3 % (5/117) of primary BC and matching lymph node (LN) metastases. Three AR negative primary BCs were positive in the matching LN metastasis, representing 17.6 % of all negative BCs with lymph node metastases (3/17). Two AR positive primary BCs were negative in the matching LN metastasis, representing 2.0 % of all AR positive BCs with LN metastases (2/100). No discrepancies were seen between primary BC and distant metastases or recurrence (n=17).
Answer: Most primary (87 %) and metastasized (86.1 %) BCs are AR positive including a significant fraction of TNBCs (11.4 %). Further, AR status is highly conserved during tumor progression and a change only occurs in a small fraction (4.1 %). Our study supports the notion that targeting AR could be effective for many BC patients and that re-testing of AR status in formerly negative or mixed type BC's is recommended.

Ex Output:
Is androgen receptor status highly conserved during tumor progression of breast cancer?

Ex Input:
Context: The blood-brain barrier (BBB) formed by brain endothelial cells interconnected by tight junctions is essential for the homeostasis of the central nervous system. Although studies have shown the importance of various signaling molecules in BBB formation during development, little is known about the molecular basis regulating the integrity of the adult BBB.', 'Using a mouse model with tamoxifen-inducible endothelial cell-restricted disruption of ctnnb1 (iCKO), we show here that endothelial -catenin signaling is essential for maintaining BBB integrity and central nervous system homeostasis in adult mice. The iCKO mice developed severe seizures accompanied by neuronal injury, multiple brain petechial hemorrhages, and central nervous system inflammation, and all had postictal death. Disruption of endothelial -catenin induced BBB breakdown and downregulation of the specific tight junction proteins claudin-1 and -3 in adult brain endothelial cells. The clinical relevance of the data is indicated by the observation of decreased expression of claudin-1 and nuclear -catenin in brain endothelial cells of hemorrhagic lesions of hemorrhagic stroke patients.
Answer: These results demonstrate the prerequisite role of endothelial -catenin in maintaining the integrity of adult BBB. The results suggest that BBB dysfunction secondary to defective -catenin transcription activity is a key pathogenic factor in hemorrhagic stroke, seizure activity, and central nervous system inflammation.

Ex Output:
Does endothelial -Catenin Signaling be Required for Maintaining Adult Blood-Brain Barrier Integrity and Central Nervous System Homeostasis?

Ex Input:
Context: To examine the relationship between cardiovascular fitness (VO(2)max) and abdominal obesity (waist circumference) and individual cardiovascular disease (CVD) risk factors, as well as a clustered risk factor profile, and to study the impact of gender, age and smoking on these relationships.', 'Cross-sectional.', 'Astrand Laboratory of Work Physiology, Swedish School of Sport and Health Sciences, Stockholm, Sweden.', 'Men (n = 781) and women (n = 890) from two random population-based samples of Swedish women and men aged 20 to 65 years.', 'Odds ratios.', 'Each unit of higher fitness was associated with a decrease in all individual risk factors ranging from 2% to 4% independent of waist circumference, each unit of higher waist circumference was associated with an increased risk ranging from 2% to 5% independent of fitness. For clustering of three or more of the risk factors, each unit of fitness was associated with a 5% decrease in risk and each unit of waist circumference with a 5% increase in risk. The clustered risk was higher in unfit participants who were older or smoked daily, regardless of waist circumference. Obese participants were at higher risk if they were men or older, regardless of fitness level. However, neither a higher fitness level nor lean status reduced the risk associated with smoking.
Answer: Higher fitness and lower waist circumference are each independently associated to a similar extent with a lower CVD risk. Simultaneous evaluation of both fitness and abdominal obesity status in clinical practice is important.

Ex Output:
Are fitness and abdominal obesity independently associated with cardiovascular risk?