Instructions: 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.
Input: Context: The aim of this study was to evaluate the expression of vascular endothelial growth factor (VEGF) in response to retinoic acid (RA) in human retinal pigment epithelial cells.', 'Expression of VEGF in human ARPE-19 cells was determined by a semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). mRNA stability was assessed after the administration of actinomycin D. The induction of the VEGF gene by various RAs was also determined by semiquantitative RT-PCR.', 'All-trans retinoic acid (atRA) time-dependently increased VEGF mRNA levels. The effect of atRA was dose-dependent in a range between 10(-7) M and 10(-6) M. Treatment with actinomycin D revealed that atRA induces the VEGF gene at the transcriptional level. Of the various RAs tested, atRA was the most potent inducer of the VEGF gene.
Answer: We demonstrated that atRA stimulates the induction of the VEGF gene in ARPE-19 cells, suggesting a novel pathway for the development of age-related macular degeneration.
Output:
Does retinoic acid induce VEGF gene expression in human retinal pigment epithelial cells ( ARPE-19 )?