Identification of NAG-1 (Non-steroidal anti-inflammatory activated gene) Gene expression levels in nasal polyp tissue

Nasal polyposis is a chronic inflammatory disease of the nasal and paranasal sinus mucosa. Etiopathogenesis is still not understood exactly but chronic inflammation is accepted to be the most important factor in polyp development. Nasal polyposis is accepted to be the common result of different etiologic factors which make chronic inflammation.We investigated a different genetic pathway which may have a potential role in this chronic inflammation and we came up with NAG-1 gene which is known to have anti-cancerogen and anti-inflammatory effects. We hypothesised that down-regulation of this gene may result in nasal polyposis and so we compared the gene expression levels in polyp tissue and healthy nasal mucosa of the same patients.This is the first study showing NAG-1 gene expression with Real-time PCR in polyp tissue and the second one showing NAG-1 expression in healthy nasal mukosa. We saw a heterogenous gen expression levels as it was icreased in some patients and decreased in the others. We didn?t see any statistically significant difference in the expression levels of NAG-1 gene in polyp tissue compared with healthy nasal mukosa (p>0.05).In the patients with co-morbid asthma NAG-1 gene expression was at least two fold decreased and it was 1,5 fold increased in the others with no asthma co-morbidity. But these results were not significant statistically as a consequence of the lesser subjects in this sub-groups (p>0.05). At least these results have shown one more time that all the nasal polyposis cases can not be explained with the same etiopathogenesis.It is very clear that we can not postulate a relation with NAG-1 gene and nasal polyposis etiopathogenesis with only the results of this study. This NAG-1 gene expression difference between sub-groups, as it was at least two fold decreased in asthma group and 1,5 fold increased in the others with no asthma co-morbidity give us the idea that it may be responsible of polyp development in some nasal polyposis co-morbidities like asthma.In conclusion we think that NAG-1 gene with its well known anti-inflammatory effects, must be investigated more compherensively in the etiopathogenesis of nasal polyposis with other studies also including NAG-1 protein.