| Abstract: | OBJECTIVE: To study the expression of COX-1 and COX-2 in the remodeled lung in systemic
sclerosis (SSc) and idiopathic pulmonary fibrosis (IPF) patients,
correlating that expression with patient survival. METHODS: We examined open lung biopsy specimens from 24 SSc patients and 30 IPF
patients, using normal lung tissue as a control. The histological patterns
included fibrotic nonspecific interstitial pneumonia (NSIP) in SSc patients
and usual interstitial pneumonia (UIP) in IPF patients. We used
immunohistochemistry and histomorphometry to evaluate the expression of
COX-1 and COX-2 in alveolar septa, vessels, and bronchioles. We then
correlated that expression with pulmonary function test results and
evaluated its impact on patient survival. RESULTS: The expression of COX-1 and COX-2 in alveolar septa was significantly higher
in IPF-UIP and SSc-NSIP lung tissue than in the control tissue. No
difference was found between IPF-UIP and SSc-NSIP tissue regarding COX-1 and
COX-2 expression. Multivariate analysis based on the Cox regression model
showed that the factors associated with a low risk of death were younger
age, high DLCO/alveolar volume, IPF, and high COX-1 expression in alveolar
septa, whereas those associated with a high risk of death were advanced age,
low DLCO/alveolar volume, SSc (with NSIP), and low COX-1 expression in
alveolar septa. CONCLUSIONS: Our findings suggest that strategies aimed at preventing low COX-1 synthesis
will have a greater impact on SSc, whereas those aimed at preventing high
COX-2 synthesis will have a greater impact on IPF. However, prospective
randomized clinical trials are needed in order to confirm that. |
