Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0033377 (prolapse)
 11,717 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pelvic organ prolapse (POP) is a common, debilitating disorder affecting millions of women. Uterosacral ligaments (USLs) are the main supportive structures of the uterus and vagina and are often attenuated in women with POP. Although the mechanical strength of USLs is known to be dependent on collagen synthesis and catabolism and the degradation protein MMP2 has been implicated in POP, the molecular mechanisms involved in the development of POP are currently unknown. Homeobox (HOX) genes are transcriptional regulators that orchestrate embryonic development of the urogenital tract. We demonstrated here that HOXA11 was essential for organogenesis of the USL by showing that USLs were absent in Hoxa11-null mice. We compared expression of HOXA11, collagen type I, collagen type III, MMP2, and MMP9 in USLs of women with and without POP. Expression of HOXA11 and both collagens was dramatically decreased while MMP2 was increased in women with POP. Constitutive expression of Hoxa11 in murine fibroblasts resulted in significantly increased expression of collagen type III and decreased expression of MMP2. These results identified HOXA11 as an essential gene for the development of the USL and suggested that women with POP might have weakened connective tissue due to changes in a signaling pathway involving HOXA11, collagen type III, and MMP2.
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PMID:HOXA11 is critical for development and maintenance of uterosacral ligaments and deficient in pelvic prolapse. 1827 72

The uterosacral ligaments (USLs) are key support structures of the uterus and upper vagina. Previously, we have shown that HOXA11 is necessary for the development of the USLs, is deficient in women with pelvic organ prolapse (POP) and regulates expression of extracellular matrix (ECM) proteins. Here we sought to determine if HOXA11 regulates cell proliferation in the USLs in women. Like others, we have found that, there is decreased cellularity in prolapsed USLs compared to USLs in women with normal pelvic support. We have also demonstrated that HOXA11 promotes cell proliferation in murine fibroblasts and primary human USL cells in vitro. These findings support a relationship between HOXA11 expression, rates of proliferation and phenotypic abnormalities in the USL. Based on these findings, we sought to determine if HOXA11 regulates p53, a tumor suppressor gene which controls progression through the cell cycle and regulates ECM genes. We have demonstrated that expression of HOXA11 represses expression of p53, suggesting a mechanism by which HOXA11 regulates of the morphology and integrity of the USLs. A better understanding of the influence of these genes on the homeostasis of the ECM and interactions with each other may prove beneficial in defining the underlying etiologies of the development of POP and aid in the development of new treatment options for women with this disorder.
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PMID:HOXA11 promotes fibroblast proliferation and regulates p53 in uterosacral ligaments. 1937 92

The pathophysiology of pelvic floor disorders still remains not well understood. Increasing age as well as vaginal multiparity are the main commonly accepted factors. The hypothesis of a defect of connective tissues of the pelvic floor with aging due to collagen deficiency and/or elastic fiber degradation is often highlighted. The issue of a potential protective role of HRT is also discussed although the recent results from the WHI would suggest a negative impact of HRT on urinary incontinence, especially when HRT is initiated in elderly women, far from the menopause. Nevertheless, environmental factors cannot explain the full pathogenesis of pelvic organ prolapse (POP) and the contribution of genetic factors to the development of pelvic floor disorders is widely recognized. Support for a genetic influence on POP derives from reports suggesting that heritability is a strong contributing factor and a familial history of POP is considered as a classical risk factor. However, the characterization of the underlying molecular mechanisms remains limited, since POP may be considered the end result of a multifactorial process leading to destruction of vaginal wall connective tissue. Experimental studies in mice with null mutations in the genes encoding different putative factors involved in elastic fibers remodeling and homeostasis are crucial in the understanding of the pathogenesis of POP. Mice with null mutation in the gene encoding lysyl oxidase-like 1 (LOXL1) or fibulin-5, demonstrate signs of elastinopathy including the development of a POP in the postpartum. Likewise, homeobox genes such as HOXA11, which are essential in the embryonic development of the urogenital tract might also be involved in the pathogenesis of POP. The better understanding of the underlying determinants of pelvic floor disorders with a special focus on genetic factors may offer new therapeutic strategies, in addition to or replacement of surgical procedures.
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PMID:[Connective tissue and prolapse genesis]. 2057 47

Homeobox (HOX) genes are evolutionarily conserved genes encoding transcription factors that regulate mammalian embryonic growth and development of the urogenital tract. In both humans and mice, HOXA11 persists in the adult reproductive tract and is thought to play an important role in maintaining tissue developmental plasticity by regulating the expression of genes involved in extracellular matrix metabolism in the reproductive organs. Previously, we have shown that HOXA11 is necessary for development of the uterosacral ligaments in mice and is deficient in women with pelvic organ prolapse. Therefore, we hypothesized that Hoxa11 regulates the synthesis and/or metabolism of collagens in the uterosacral ligaments and uterus, and tested this by establishing an in utero and peritoneal Hoxa11 gene knockdown system in C57/BL6 mice using vectors bearing Hoxa11 short hairpin RNA. Specific knockdown of Hoxa11 transcripts and protein levels were confirmed versus control vectors. Protein and mRNA expression of collagen types I and III exhibited significant decreases following Hoxa11 knockdown according to Western blot analysis and real-time PCR. Tissue inhibitor of matrix metalloproteinase 1 (MMP1) expression also exhibited a significant decrease. Gelatinase zymography confirmed increases in pro-MMP2 and MMP9, as well as activated MMP2, following Hoxa11 knockdown. These results reveal that Hoxa11 knockdown in the uterosacral ligaments and uterus increases extracellular matrix degradation. More importantly, it suggests a mechanism in the weakening of the pelvic floor support in women, because decreased HOXA11 gene expression has been reported to be associated with decreased collagen and increased MMP2 expression in the uterosacral ligaments of women with pelvic organ prolapse.
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PMID:Knockdown of Hoxa11 in vivo in the uterosacral ligament and uterus of mice results in altered collagen and matrix metalloproteinase activity. 2230 91

The balanced turnover of collagen is necessary to maintain the mechanical strength of pelvic supportive connective tissues. Homeobox (HOX) A11 is a key transcriptional factor that controls collagen metabolism and homoeostasis in the uterosacral ligaments (USLs), and the deficient HOXA11 signalling may contribute to alterations in the biochemical strength of the USLs, leading to pelvic organ prolapse (POP). However, it is unknown how HOXA11 transcripts are regulated in the USLs. In this study, we found that microRNA (miRNA)-30d and 181a were overexpressed in women with POP, and their expression was inversely correlated with HOXA11 mRNA levels. The overexpression of miR-30d or 181a suppressed HOXA11 mRNA and protein levels in 293T cells, whereas the knockdown of these miRNAs enhanced HOXA11 levels and collagen production. Cotransfection of a luciferase reporter plasmid containing the 3'-untranslated region of HOXA11 with miR-30d or 181a mimic resulted in decreased relative luciferase activity. Conversely, cotransfection with anti-miR-30d or 181a increased luciferase activity. Taken together, these results indicate that both miR-30d and 181a are important posttranscriptional regulators of HOXA11 in the USLs and could be a potential therapeutic target for POP.
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PMID:MicroRNA-30d and microRNA-181a regulate HOXA11 expression in the uterosacral ligaments and are overexpressed in pelvic organ prolapse. 2563 Sep 74