Expression of forkhead transcription factors in human granulosa cells.

Members of the forkhead box O1 (FOXO) family of transcription factors are expressed in granulosa cells during various stages of follicle development, and evidence from rodent and other model systems suggests that they may be involved in regulating follicular activation and oocyte maturation. In this report, we show that FOXO1, FOXO3, and FOXO4 are expressed in human luteinized mural granulosa cells, which may suggest that these transcription factors are also involved in human folliculogenesis and luteinization.