Lim1/LIM1 is expressed in developing and adult mouse and human endometrium.

Lim1 encodes a homeodomain transcription factor required for head, kidney and female reproductive tract development in the murine embryo. Recently, Lim1 expression was documented in several adult murine and human organs. In the developing female reproductive tract, Lim1 expression was first detected in the Müllerian ducts. Using immunofluorescence, we detected LIM1 expression in a developmental model of human female reproductive tract which was established by recombination of neonatal uterine mesenchyme with human embryonic stem cells. In addition, we report a dynamic expression of Lim1/LIM1 in neonatal and adult mouse, and adult human endometrial epithelium and stroma as revealed by immunofluorescence and quantitative real-time polymerase chain reaction. LIM1 expression was also observed in several endometrial epithelial cancer cell lines (ECC-1, Ishikawa, and HEC1A). Furthermore, we found that Activin A significantly upregulated LIM1 mRNA expression in ECC-1 cells. These studies demonstrate previously unreported Lim1/LIM1 expression in neonatal, adult mouse and human endometrium suggesting Lim1/LIM1 may have a role in endometrial development and remodelling.