title: Immunohistochemical expression of SOX9 protein in immature, mature, and neoplastic canine Sertoli cells.
abstract: Sex-determining region Y box9 gene (SOX9) protein plays a pivotal role in male sexual development. It regulates the transcription of the anti-Müllerian hormone gene promoting development of testis cords, multiplication, and maturation of Sertoli cells (SCs) and maintenance of spermatogenesis in adult testis. The immunohistochemical expression of SOX9 in normal testes has been reported in humans, mice, and rats. The present study aimed to investigate the expression of SOX9 in canine SCs during testicular maturation and neoplastic transformation. Canine testicular samples derived from three fetuses, four newborns, four prepubertal puppies, five adult dogs, 31 Sertoli cell tumors (SCTs) (one metastasizing), and five Leydig cell tumors (LCTs) were selected from departmental archive and tested immunohistochemically with a polyclonal antibody against SOX9 (1:150). All SCs from fetal, neonatal, and adult testes had a strong and exclusively nuclear labeling for SOX9. In SCs from prepubertal testes, SOX9 staining was highly variable with one negative sample (one of four), two samples with exclusively nuclear staining (two of four), and one with both nuclear and cytoplasmic labeling (one of four). Leydig cells (LCs) and LCTs were always negative. All 31 SCTs were positive for SOX9. The expression of SOX9 was nuclear, nuclear and cytoplasmic, and exclusively cytoplasmic in 18 of 31, 11 of 31, and two of 31 SCTs, respectively. This first report on the immunohistochemical expression of SOX9 in canine testes reports that in normal SCs from fetal, neonatal, and adult testes SOX9 labeled the nucleus, as in humans and laboratory animals. The cytoplasmic labeling observed in one prepubertal pairs of testes and in 11 SCTs could reflect SC immaturity or dedifferentiation, paralleling results observed in rat testes. The expression of SOX9 in SCs and SCTs and its absence in LCs and LCTs suggests that SOX9 is a reliable diagnostic marker for both normal and neoplastic SCs.
authors.affiliation: Department of Veterinary Science and Public Health, Università degli Studi di Milano, Milano, Italy.
authors.forename: Barbara
authors.initials: B
authors.lastname: Banco
authors.affiliation: School of Veterinary Science, The University of Queensland, Gatton Campus, Gatton, Queensland, Australia.
authors.forename: Chiara
authors.initials: C
authors.lastname: Palmieri
authors.affiliation: Department of Veterinary Science and Public Health, Università degli Studi di Milano, Milano, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Sironi
authors.affiliation: Department of Veterinary Science and Public Health, Università degli Studi di Milano, Milano, Italy.
authors.forename: Eleonora
authors.initials: E
authors.lastname: Fantinato
authors.affiliation: Department of Health, Animal Science, and Food Safety, Università degli Studi di Milano, Milano, Italy.
authors.forename: Maria C
authors.initials: MC
authors.lastname: Veronesi
authors.affiliation: Department of Veterinary Science and Public Health, Università degli Studi di Milano, Milano, Italy.
authors.forename: Debora
authors.initials: D
authors.lastname: Groppetti
authors.affiliation: Department of Veterinary Science and Public Health, Università degli Studi di Milano, Milano, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Giudice
authors.affiliation: Veterinary Ambulatory Martignoni, Rho (Milano), Italy.
authors.forename: Benedetta
authors.initials: B
authors.lastname: Martignoni
authors.affiliation: Department of Veterinary Science and Public Health, Università degli Studi di Milano, Milano, Italy. Electronic address: valeria.grieco@unimi.it.
authors.forename: Valeria
authors.initials: V
authors.lastname: Grieco
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor / Q000378:metabolism; D004285:Dogs / Q000378:metabolism*; D007150:Immunohistochemistry; D008297:Male; D055758:SOX9 Transcription Factor / Q000032:analysis / Q000378:metabolism*; D012708:Sertoli Cells / Q000378:metabolism* / Q000473:pathology; D013736:Testicular Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary; D013737:Testis / Q000254:growth & development / Q000378:metabolism / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; D055758:SOX9 Transcription Factor
keywords: Dog; Immunohistochemistry; SOX9; Sertoli cells; Testis