The expression of
EGF and
TGF-beta 1 was evaluated in tissue specimens in 25 children with PUJ obstruction and 15 controls with normal PUJs by immunohistochemistry, in situ hybridization, and
reverse transcriptase polymerase chain reaction (RT-PCR) techniques. All the signals of
mRNA products were normalized to the
mRNA levels of
glyceraldehyde-3-phosphate dehydrogenase (GAPDH) a housekeeping gene, as a ratio.
RESULTS: On RT-PCR study, the amount of
TGF-beta 1 mRNA in stenotic tissue was higher than in controls, in addition,
EGF gene expression in the obstructed junction was significantly lower than in normal junctions. The
TGF-beta 1 to GAPDH ratio was 0.57 +/- 0.26 and 0.36 +/- 0.19 in the stenotic tissue and the normal ureter, respectively (P =.012). The
EGF to GAPDH ratio was 0.17 +/- 0.08 and 0.37 +/- 0.14 in the stenotic tissue and the normal ureter, respectively (P =.0001). Furthermore, the positive correlations were found between
TGF-beta1 gene and
protein expression (r = 0.601; P =.001),
TGF-beta 1 gene and drainage clearance half-time (T1/2) (r = 0.474; P =.017),
TGF-beta 1 protein expression, and T1/2 (r = 0.516; P =.008). A negative correlation was found between
EGF gene and T1/2 (r = -0.448; P =.025). On immunolabeling and in situ hybridization labeling, the expression of
TGF-beta 1 protein was strongly positive and confined to the muscle cells, spindle cells, and
collagen fibers in the stenotic tissue; the expression of
TGF-beta 1 mRNA was moderately positive and mainly distributed in the
collagen of the stenotic segment, both the expression of
EGF protein and
mRNA were negative in the normal ureter.
CONCLUSIONS: