Analysis of gene expression profiles of normal human nasal mucosa and nasal polyp tissues by SAGE

Background: A systemic determination of gene expression profiles in nasal polyp compared with normal nasal mucosa would contribute considerably to the investigation of the disease marker in various rhinopathy and general knowledge on the formation of human nasal polyp. Objective: The aim of this study was to identify the transcriptome of the normal human nasal mucosa and nasal polyp by the serial analysis of gene expression. Methods: mRNA was extracted from normal inferior turbinate mucosa and nasal polyp. Short sequences (tags), each one usually corresponding to a distinct transcript, was isolated and concatemerized into long DNA molecules, which were cloned and sequenced. Results: We detected 65,305 tags for normal nasal mucosa and 55,829 tags for nasal polyp, representing 20,629 and 17,636 potential transcripts species, respectively. Of the unique tags encountered more than once, 92% (normal nasal mucosa) and 90% (nasal polyp) matched known genes or expressed sequence tags, whereas the remainder did not match any GenBank sequences. Therefore, 504 and 539 novel transcripts were identified in normal nasal mucosa and nasal polyp, respectively. Although the expression levels of most transcripts in both libraries were similar, 114 transcripts were differentially expressed at a statistically significant level (P < .05)-that is, 65 and 49 transcripts among them were expressed at a higher level in normal nasal mucosa and nasal polyp, respectively. Conclusion: This information should be very useful for basic knowledge as well as for future studies on pathophysiological conditions of human nasal mucosa, providing some clues to evaluate the altered factors in a variety of rhinopathies. Clinical implications: The results of this study might contribute to general knowledge on the formation of human nasal polyp.