title: Transforming growth factor β1 signaling coincides with epithelial-mesenchymal transition and fibroblast-to-myofibroblast transdifferentiation in the development of adenomyosis in mice.
abstract: OBJECTIVE
  Do platelets have any role in the development of adenomyosis?
  
  
  CONCLUSIONS
  Activated platelets coincide with the release of transforming growth factor (TGF)-β1 and induction of the TGF-β/Smad signaling pathway as well as evidence of epithelial-mesenchymal transition (EMT) and fibroblast-to-myofibroblast transdifferentiation (FMT) in a mouse model of adenomyosis, resulting ultimately in fibrosis, as in adenomyosis.
  
  
  BACKGROUND
  Both EMT and FMT are known to play vital roles in fibrogenesis in general and in endometriosis in particular. EMT has been implicated in the development of adenomyosis, but this was based primarily on cross-sectional observation. It is unclear as to whether adenomyotic lesions and their microenvironment have the machinery to promote EMT and FMT, resulting ultimately in fibrosis. There has not been any published study on the role of platelets in the development of adenomyosis, even though adenomyotic lesions undergo repeated cycles of tissue injury and repair, which implicates the involvement of platelets and constitutes an environment conducive for fibrogenesis.
  
  
  METHODS
  Adenomyosis was induced in 28 female ICR mice by neonatal dosing of tamoxifen. Another 32 were neonatally dosed without tamoxifen. These mice were sacrificed serially and their tissue samples were subsequently evaluated.
  
  
  METHODS
  Female ICR mice with and without induced adenomyosis were sacrificed in batch at 5, 10, 15, 42 and 60 days of age. The depth of myometrial infiltration of endometrial tissues was assessed and immunohistochemistry analysis of biomarkers of EMT and FMT, as well as TGF-β1, phosphorylated Smad3 (p-Smad3) and markers of proliferation, angiogenesis and extracellular matrix (ECM) deposits was performed in ectopic (for adenomyotic mice) and eutopic (controls) endometrial tissue samples. Masson trichrome and Van Gieson stainings were performed to quantify the extent of fibrosis in lesions. Progesterone receptor isoform B (PR-B) staining also was performed.
  
  
  RESULTS
  While TGF-β1 immunoreactivity was consistently low in control endometrium, its level was increased dramatically starting from Day 10, along with the extent of platelet aggregation. Staining for TGF-β1 and p-Smad3 increased progressively as adenomyosis progressed, along with markers for proliferation, angiogenesis and ECM deposits. Consistently, staining of vimentin (a marker for stromal or mesenchymal cells) was also increased while that of E-cadherin (a marker for epithelial cells) was reduced. PR-B staining also decreased progressively. Starting from Day 42, α-SMA staining, a marker for myofibroblasts, was elevated in lesions, while in control endometrium, it was negative. Concomitantly, the extent of fibrosis also was increased.
  
  
  CONCLUSIONS
  This study is limited by the use of histochemistry and immunohistochemistry analyses only and the lack of intervention.
  
  
  CONCLUSIONS
  Like their endometriotic counterpart, adenomyotic lesions and their microenvironment may contain all the necessary molecular machinery to promote fibrogenesis. Platelet-induced activation of the TGF-β/Smad signaling pathway may be a driving force in EMT and FMT in the development of adenomyosis, leading to fibrosis. This study provides the first piece of evidence that adenomyotic lesions are wounds that undergo repeated injury and healing, and as such, platelets play critical roles in the development of adenomyosis. It suggests the potential for the use of anti-platelet therapy in the treatment of adenomyosis, and also opens a new venue for developing novel biomarkers for diagnostic or prognostic purposes.
  
  
  BACKGROUND
  Support for data collection and analysis was provided by grants from the National Science Foundation of China. None of the authors has anything to disclose.
authors.affiliation: Shanghai Obstetrics/Gynecology Hospital, Fudan University, 419 Fangxie Road, Shanghai 200011, China.
authors.forename: Minhong
authors.initials: M
authors.lastname: Shen
authors.affiliation: Shanghai Obstetrics/Gynecology Hospital, Fudan University, 419 Fangxie Road, Shanghai 200011, China Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, Fudan University, Shanghai 200011, China.
authors.forename: Xishi
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Anatomy, Histology and Embryology, Shanghai Medical Collage, Fudan University, Shanghai 200032, China.
authors.forename: Hongqi
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Shanghai Obstetrics/Gynecology Hospital, Fudan University, 419 Fangxie Road, Shanghai 200011, China Shanghai Key Laboratory of Female Reproductive Endocrine-Related Diseases, Fudan University, Shanghai 200011, China hoxa10@outlook.com.
authors.forename: Sun-Wei
authors.initials: SW
authors.lastname: Guo
mesh_terms: D062788:Adenomyosis / Q000139:chemically induced / Q000473:pathology*; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D015820:Cadherins / Q000378:metabolism; D049109:Cell Proliferation; D054338:Cell Transdifferentiation; D004717:Endometrium / Q000378:metabolism / Q000473:pathology; D058750:Epithelial-Mesenchymal Transition; D005260:Female; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D007150:Immunohistochemistry; D051379:Mice; D008813:Mice, Inbred ICR; D058628:Myofibroblasts / Q000166:cytology / Q000378:metabolism; D009389:Neovascularization, Pathologic / Q000378:metabolism; D010974:Platelet Aggregation; D011980:Receptors, Progesterone / Q000378:metabolism; D015398:Signal Transduction; D051900:Smad3 Protein / Q000378:metabolism; D053773:Transforming Growth Factor beta1; D014746:Vimentin / Q000378:metabolism
chemical_list: D015415:Biomarkers; D015820:Cadherins; D011980:Receptors, Progesterone; D051900:Smad3 Protein; C497791:Smad3 protein, mouse; D053773:Transforming Growth Factor beta1; D014746:Vimentin; C097314:progesterone receptor B
keywords: TGF-β1; adenomyosis; epithelial–mesenchymal transition; fibroblast-to-myofibroblast transdifferentiation; fibrosis; mouse; platelet