Renal expression of epidermal growth factor and transforming growth factor-beta1 in children with congenital hydronephrosis.

OBJECTIVES: To study the potential role of pelviureteral junction obstruction (PUJO) in causing progressive renal damage in children through the renal expression of epidermal growth factor (EGF) and transforming growth factor-beta1 (TGF-beta1).
METHODS: The expression of EGF and TGF-beta1 was evaluated in the renal tissues of 25 children with congenital hydronephrosis by immunohistochemistry, in situ hybridization, and reverse transcriptase polymerase chain reaction techniques.
RESULTS: Children with PUJO had a significant increase in TGF-beta1 and a marked reduction in EGF expression compared with controls. The TGF-beta1/glyceraldehyde phosphate dehydrogenase ratio in the hydronephrotic kidney and normal kidney was 0.53 +/- 0.13 and 0.24 +/- 0.10 respectively, and the difference was significant (P = 0.000). The EGF/glyceraldehyde phosphate dehydrogenase ratio in the hydronephrotic kidney and normal kidney was 0.15 +/- 0.06 and 0.55 +/- 0.13, respectively, and the difference was also significant (P = 0.0001). Positive correlations were found between the TGF-beta1 gene and the drainage clearance half-time (r = 0.47; P = 0.018), TGF-beta1 protein and drainage clearance half-time (r = 0.44; P = 0.028), TGF-beta1 gene and histologic grade (r = 0.53; P = 0.006), and TGF-beta1 protein and histologic grade (r = 0.76; P = 0.000). Negative correlations were found between the EGF gene and drainage clearance half-time (r = -0.59; P = 0.002), EGF protein and drainage clearance half-time (r = -0.61; P = 0.001), EGF gene and histologic grade (r = -0.58; P = 0.003), and EGF protein and histologic grade (r = -0.47; P = 0.019).
CONCLUSIONS: TGF-beta1 expression was increased and EGF expression was decreased in the renal tissue after clinical PUJO. The alterations of TGF-beta1 and EGF may play a potential role in the pathogenesis of renal damage in PUJO.