Differential gene expression in uterosacral ligament and full thickness anterior vaginal tissues from patients with recurrent and primary pelvic organ prolapse

Pelvic organ prolapse (POP) represents a gynecologic disease affecting many women. The lifetime risk, to age 80, of women undergoing surgery for prolapse or urinary incontinence is approximately 11%. This disease is known to be multifactorial and numerous studies looking at this issue have preceded ours. The objective of this study was to profile differential gene expression in three distinct patient groups. Our groups consisted of women with recurrent POP, women with primary POP and women without POP. We looked at whole human genome DNA using microarray analysis technology. The tissue evaluated was anterior vaginal wall tissue and uterosacral ligament (USL) tissues. We identified in USL tissue 10 genes of interest. Eight genes were over expressed and two genes were under expressed. Confirmation of degree of gene expression for these ten genes was performed by using the technique of real-time RT-PCR. The vaginal tissues contributed no genes of interest. Of the genes found to be over expressed in USL tissue, we found that five of the eight genes which were over expressed functioned in the task of distribution, metabolism or deposition of adipose tissue. The two genes of greatest interest that were under expressed in USL tissue were the HOXA genes D10 and D11. These two genes have been identified in earlier microarray studies as being under expressed in patients with POP. We hypothesis that the differentially expressed genes found to be over expressed in USL tissues suggest that the pelvic support tissue, USL's, are being transformed over time in this patient group leading to their increased occurrence of recurrent POP.