Aurora B expression in normal testis and seminomas.
Aurora/Ipl1-related kinases are a conserved family of proteins that have multiple functions during mitotic progression. High levels of Aurora kinases are characteristic of rapidly dividing cells and tumours. Aurora B encodes a protein that associates with condensing chromatin, concentrates at centromeres, and then relocates onto the central spindle at anaphase. In this study the expression and the localisation of Aurora B throughout germinal epithelial progression in normal testis and its neoplastic counterpart were analysed. Immunocytochemistry and RT-PCR analysis of mouse germinal epithelium cells showed the presence of Aurora B in spermatogonia and occasionally in spermatocytes. Western blot analysis revealed the typical Aurora B isoform ( approximately 41 kDa) in the same cellular types. A similar distribution was observed in human testis by immunohistochemistry. Moreover, the distribution and the expression of Aurora B were investigated in neoplasms derived from germ cells. Surgical samples of seminomas were analysed, and a high percentage of Aurora B positive cells (51%) was detected; the expression of Aurora B was significantly related to the MIB-1 proliferation marker (R=0.816). The data presented here demonstrate that Aurora B expression occurs in spermatogonial division. Furthermore, our results indicate that the expression of Aurora B is a consistent feature of human seminomas.
Chieffi
P
P
Dipartimento di Medicina Sperimentale, II Università di Napoli, Naples, Italy. Paolo.Chieffi@unina2.it
Troncone
G
G
Caleo
A
A
Libertini
S
S
Linardopoulos
S
S
Tramontano
D
D
Portella
G
G
D000818:Animals; D064107:Aurora Kinase B; D064127:Aurora Kinases; D015415:Biomarkers / Q000032:analysis; D002455:Cell Division; D007150:Immunohistochemistry / Q000379:methods; D007527:Isoenzymes / Q000032:analysis* / Q000235:genetics; D019394:Ki-67 Antigen / Q000032:analysis; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D017346:Protein Serine-Threonine Kinases / Q000032:analysis* / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018239:Seminoma / Q000201:enzymology*; D013090:Spermatocytes / Q000201:enzymology; D013093:Spermatogonia / Q000201:enzymology; D013094:Spermatozoa / Q000201:enzymology*; D013736:Testicular Neoplasms / Q000201:enzymology*; D013737:Testis / Q000201:enzymology*
D015415:Biomarkers; D007527:Isoenzymes; D019394:Ki-67 Antigen; D012333:RNA, Messenger; C576921:AURKB protein, human; C576924:Aurkb protein, mouse; D064107:Aurora Kinase B; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases