Decreased mRNA transcripts of M-phase promoting factor and its regulators in the testes of infertile men

Abstract

M-phase promoting factor (MPF), which is comprised of Cyclin B and a catalytic subunit, Cdc2, is a key enzyme required for cells to enter M phase in both mitosis and meiosis. MPF activity is controlled by the stimulatory dephosphorylation of the Cdc25 family and the inhibitory phosphorylation of Wee1. We determined the levels of mRNA transcripts of MPF and its regulators in the testes of infertile men, and evaluated the relationship between the transcript levels and patients' testicular phenotypes and sperm retrieval results. The mRNA transcript levels of CDC2, CCNB1, CCNB2, CDC25A, CDC25B, CDC25C and WEE1 in the testes of 37 azoospermic patients were examined by quantitative real-time polymerase chain reaction. Significant decreases in CDC2, CCNB1, CCNB2, CDC25A, CDC25C and WEE1 mRNA transcript levels were detected in patients with spermatogenic failure. CDC2 mRNA transcript levels correlated significantly with those of CCNB1 and CCNB2 mRNA. Significantly higher CDC2, CCNB1, CCNB2, CDC25C and WEE1 mRNA transcript levels were detected in 18 patients with successful sperm retrieval than in 11 patients with failed sperm retrieval. We suggest that the decreased mRNA transcripts of MPF and its regulators play important roles in human spermatogenesis.