Ectopic expression of Sonic Hedgehog in a cryptorchid man with azoospermia: a case report.

A 30-year-old man presented with a left undescended testis, right testicular deficiency and azoospermia. Testicular biopsy revealed an absence of spermatocytes and increased numbers of Leydig cells in the undescended testis. Additional comparative analyses were undertaken to explore Sonic Hedgehog (Shh) immunostaining in the testis of juvenile and adult mice, in the testis of the patient with cryptorchidism, and in archival testicular tissue from a patient with obstructive azoospermia and a patient with prostate cancer. Shh immunostaining was demonstrated in spermatocytes in juvenile and adult mouse testis and in the patients with obstructive azoospermia and prostate cancer, suggesting that Shh signalling is involved in normal spermatogenesis. In the patient with cryptorchidism, Shh immunostaining was localized to the Leydig cells, which suggests that Shh might be involved in the abnormal expansion of the Leydig cell population in the testis. These preliminary data on the appearance of Shh protein during normal spermatogenesis might provide the basis for further investigations to clarify the role of Shh signalling in spermatogenesis during normal and pathogenic testis development.