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.