TGF-β1 and IGF-1 Production and Recurrence of Crohn's Disease After Ileo-Colonic Resection

Background: Recurrence after surgery is a major problem in the treatment of Crohn's disease (CD). Alteration of healing processes may play a role in this phenomenon. Transforming growth factor beta (TGF-β) and insulin-like growth factor (IGF-1) have pro-fibrogenic properties and are involved in wound-healing mechanisms. The aim of this study was to assess their role in the CD recurrence after ileo-colonic resection. Patients and methods: Twenty patients with CD, who underwent ileo-colonic resection in the period between 1999 and 2005, were enrolled in this study. Tissue samples were obtained from macroscopically diseased and healthy ileum. The TGF-β1 and IGF-1 mRNAs were quantified by real-time polymerase chain reaction using glyceraldehyde 3-phosphate dehydrogenase as the housekeeping gene. Histological severity of the disease was assessed to quantify the ileal inflammation. Patients' follow-up was investigated. Comparisons and correlations were carried out with nonparametric tests and survival analysis was performed. Results: Histological inflammation was moderately severe in the diseased bowel, while it was absent in healthy segments (P <0.01). TGF-β1 production in healthy bowels showed a direct correlation with clinical CD recurrence (τ = 0.43, P = 0.04) and survival analysis showed that patients who expressed high TGF-β1 mRNA transcripts in healthy intestines had higher cumulative recurrence rates than those who expressed low TGF-β1 mRNA levels (P = 0.02). Conclusion: Our study suggests that the high levels of TGF-β1 in healthy bowels of patients who undergo ileo-colonic resection for CD are associated with early clinical disease recurrence, while there seems to be no association between IGF-1 and CD recurrence.