Non-invasive IGFBP1, IGFBP2 biomarkers as predictors and outcomes of usual interstitial pneumonia (UIP) therapeutic response

Background Usual interstitial pneumonia (UIP) is a fatal disease that is associated with poor prognosis and survival. Several growth factors such as IGFs (insulin-like growth factors) and IGFBPs (insulin-like growth factor binding proteins) seem to take part to this pathogenesis. Pirfenidone is an immunosuppressant drug that is thought to have anti-inflammatory and anti-fibrotic effects both in vitro and in vivo. Objective To assess IGFBP1 and IGFBP2 as non-invasive biomarkers for prediction and outcomes of UIP clinical activity and therapeutic response to the anti-fibrotic pirfenidone. Results Serum levels of IGFBP1 and IGFBP2 were significantly higher in the UIP group than in the healthy subjects ( p ≤ 0.005). After 6 months therapy, UIP patients were divided into 2 groups according to improvement in MRC dyspnea grading into clinically improved and non-improved groups. 6MWT and SPaO2 were significantly improved in the clinically improved group compared to the non-improved one with no differences as regards other parameters ( p < 0.0001). Both IGFBP1 and IGFBP2 were significantly decreased in serum while only IGFBP2 was decreased in BAL of all UIP after completing 12 months therapy. Conclusion IGFBP1 and IGFBP2 were increased in active UIP patients and reduced after 12 months anti-fibrosing therapy. IGFBPs may be promising biomarkers and predictors of response to therapy in UIP.