Apoptosis-related proteins in the testes of infertile men with varicocele.
OBJECTIVE
To assess immunohistochemically the expression of apoptosis-related proteins in the testes of infertile men, to determine which of these proteins were related to hypospermatogenesis, as a previous report suggested that apoptosis was suppressed in infertile men with varicocele.


METHODS
The expression of Bcl-2, Bax, caspase-1 (ICE) and caspase-3 (CPP32) were examined in bilateral testicular specimens from 26 infertile men with varicocele and six normal testicular specimens, using the avidin-biotin-peroxidase complex method. Clinical variables were also assessed.


RESULTS
Bax, ICE, and CPP32 were expressed in germ cells, while Bcl-2 was not. Differences in staining in left or right testes were not significant. In both testes of infertile patients with varicocele, significantly fewer germ cells stained for CPP32 than in controls (P < 0.001). For Bax and ICE, total germ cell staining was similar between these groups. Staining was less frequent in infertile patients for both CPP32 and ICE when the analysis was restricted to spermatogonia. Serum luteinizing hormone levels correlated positively with CPP32 staining (P = 0.0457).


CONCLUSIONS
The reduced expression of CPP32 participates in regulating apoptosis in the testes of infertile men with varicocele.
Tanaka
Hiroyuki
H
Division of Urology, Department of Organs Therapeutics, Faculty of Medicine, Kobe University Graduate School of Medicine, Kobe, Japan.
Fujisawa
M
M
Tanaka
Hirokazu
H
Okada
H
H
Kamidono
S
S
D000328:Adult; D020170:Caspase 1 / Q000378:metabolism*; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism*; D005854:Germ Cells / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007248:Infertility, Male / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D013737:Testis / Q000378:metabolism*; D014646:Varicocele / Q000378:metabolism*; D051028:bcl-2-Associated X Protein
C494826:BAX protein, human; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases; D020170:Caspase 1