Author
Agnieszka E. Gorska
Other affiliations: Vanderbilt University Medical Center
Bio: Agnieszka E. Gorska is an academic researcher from Vanderbilt University. The author has contributed to research in topics: Transforming growth factor & Transforming growth factor beta. The author has an hindex of 29, co-authored 45 publications receiving 5927 citations. Previous affiliations of Agnieszka E. Gorska include Vanderbilt University Medical Center.
Papers
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TL;DR: TGF-β signaling in fibroblasts modulates the growth and oncogenic potential of adjacent epithelia in selected tissues and is associated with intraepithelial neoplasia in prostate and invasive squamous cell carcinoma of the forestomach.
Abstract: Stromal cells can have a significant impact on the carcinogenic process in adjacent epithelia. The role of transforming growth factor-beta (TGF-beta) signaling in such epithelial-mesenchymal interactions was determined by conditional inactivation of the TGF-beta type II receptor gene in mouse fibroblasts (Tgfbr2fspKO). The loss of TGF-beta responsiveness in fibroblasts resulted in intraepithelial neoplasia in prostate and invasive squamous cell carcinoma of the forestomach, both associated with an increased abundance of stromal cells. Activation of paracrine hepatocyte growth factor (HGF) signaling was identified as one possible mechanism for stimulation of epithelial proliferation. Thus, TGF-beta signaling in fibroblasts modulates the growth and oncogenic potential of adjacent epithelia in selected tissues.
1,332 citations
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TL;DR: It is demonstrated that Gr-1+CD11b+ myeloid cells are recruited into mammary carcinomas with type II TGF beta receptor gene (Tgfbr2) deletion and directly promote tumor metastasis.
881 citations
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TL;DR: The data show that blockade of TGF-beta signaling and activated Ras signaling cooperate to promote PDAC progression, which indicated a haploinsufficiency of T GF- beta signaling in this genetic context.
Abstract: Pancreatic ductal adenocarcinoma (PDAC) is an almost uniformly lethal disease in humans. Transforming growth factor-β (TGF-β) signaling plays an important role in PDAC progression, as indicated by the fact that Smad4, which encodes a central signal mediator downstream from TGF-β, is deleted or mutated in 55% and the type II TGF-β receptor (Tgfbr2) gene is altered in a smaller subset of human PDAC. Pancreas-specific Tgfbr2 knockout mice have been generated, alone or in the context of active Kras (KrasG12D) expression, using the Cre-loxP system driven by the endogenous Ptf1a (pancreatic transcription factor-1a) locus. Pancreas-selective Tgfbr2 knockout alone gave no discernable phenotype in 1.5 yr. Pancreas-specific KrasG12D activation alone essentially generated only intraepithelial neoplasia within 1 yr. In contrast, the Tgfbr2 knockout combined with KrasG12D expression developed well-differentiated PDAC with 100% penetrance and a median survival of 59 d. Heterozygous deletion of Tgfbr2 with KrasG12D expression also developed PDAC, which indicated a haploinsufficiency of TGF-β signaling in this genetic context. The clinical and histopathological manifestations of the combined KrasG12D expression and Tgfbr2 knockout mice recapitulated human PDAC. The data show that blockade of TGF-β signaling and activated Ras signaling cooperate to promote PDAC progression.
349 citations
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TL;DR: Inhibition of Gr-1+CD11b+ cells could normalize the premetastatic lung environment, improve host immunosurveillance, and inhibit tumor metastasis.
Abstract: The mechanisms by which a primary tumor affects a selected distant organ before tumor cell arrival remain to be elucidated. This report shows that Gr-1+CD11b+ cells are significantly increased in lungs of mice bearing mammary adenocarcinomas before tumor cell arrival. In the premetastatic lungs, these immature myeloid cells significantly decrease IFN-gamma production and increase proinflammatory cytokines. In addition, they produce large quantities of matrix metalloproteinase 9 (MMP9) and promote vascular remodeling. Deletion of MMP9 normalizes aberrant vasculature in the premetastatic lung and diminishes lung metastasis. The production and activity of MMP9 is selectively restricted to lungs and organs with a large number of Gr-1+CD11b+ cells. Our work reveals a novel protumor mechanism for Gr-1+CD11b+ cells that changes the premetastatic lung into an inflammatory and proliferative environment, diminishes immune protection, and promotes metastasis through aberrant vasculature formation. Thus, inhibition of Gr-1+CD11b+ cells could normalize the premetastatic lung environment, improve host immunosurveillance, and inhibit tumor metastasis.
319 citations
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TL;DR: It is demonstrated that overexpression of TGF-alpha 1 in vivo can markedly suppress mammary tumor development and that MMTV-TGF-beta 1 transgenic mice are resistant to 7,12-dimethylbenz[a]anthracene-induced mammary tumors.
Abstract: In cell culture, type alpha transforming growth factor (TGF-alpha) stimulates epithelial cell growth, whereas TGF-beta 1 overrides this stimulatory effect and is growth inhibitory. Transgenic mice that overexpress TGF-alpha under control of the mouse mammary tumor virus (MMTV) promoter/enhancer exhibit mammary ductal hyperplasia and stochastic development of mammary carcinomas, a process that can be accelerated by administration of the chemical carcinogen 7,12-dimethylbenz[a]anthracene. MMTV-TGF-beta 1 transgenic mice display mammary ductal hypoplasia and do not develop mammary tumors. We report that in crossbreeding experiments involving the production of mice carrying both the MMTV-TGF-beta 1 and MMTV-TGF-alpha transgenes, there is marked suppression of mammary tumor formation and that MMTV-TGF-beta 1 transgenic mice are resistant to 7,12-dimethylbenz[a]anthracene-induced mammary tumor formation. These data demonstrate that overexpression of TGF-beta 1 in vivo can markedly suppress mammary tumor development.
293 citations
Cited by
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TL;DR: The principal mechanisms that govern the effects of inflammation and immunity on tumor development are outlined and attractive new targets for cancer therapy and prevention are discussed.
8,664 citations
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TL;DR: The origin, mechanisms of expansion and suppressive functions of MDSCs, as well as the potential to target these cells for therapeutic benefit are discussed.
Abstract: Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of cells that expand during cancer, inflammation and infection, and that have a remarkable ability to suppress T-cell responses. These cells constitute a unique component of the immune system that regulates immune responses in healthy individuals and in the context of various diseases. In this Review, we discuss the origin, mechanisms of expansion and suppressive functions of MDSCs, as well as the potential to target these cells for therapeutic benefit.
5,811 citations
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TL;DR: Fibroblasts are a key determinant in the malignant progression of cancer and represent an important target for cancer therapies.
Abstract: Tumours are known as wounds that do not heal - this implies that cells that are involved in angiogenesis and the response to injury, such as endothelial cells and fibroblasts, have a prominent role in the progression, growth and spread of cancers. Fibroblasts are associated with cancer cells at all stages of cancer progression, and their structural and functional contributions to this process are beginning to emerge. Their production of growth factors, chemokines and extracellular matrix facilitates the angiogenic recruitment of endothelial cells and pericytes. Fibroblasts are therefore a key determinant in the malignant progression of cancer and represent an important target for cancer therapies.
4,232 citations
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TL;DR: Understanding of the origins and nature of cancer metastasis and the selection of traits that are advantageous to cancer cells is promoted.
3,863 citations
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TL;DR: Current understanding of the cellular and molecular mechanisms of fibrogenesis is explored and components of the renin–angiotensin–aldosterone system (ANG II) have been identified as important regulators of fibrosis and are being investigated as potential targets of antifibrotic drugs.
Abstract: Fibrosis is defined by the overgrowth, hardening, and/or scarring of various tissues and is attributed to excess deposition of extracellular matrix components including collagen. Fibrosis is the end result of chronic inflammatory reactions induced by a variety of stimuli including persistent infections, autoimmune reactions, allergic responses, chemical insults, radiation, and tissue injury. Although current treatments for fibrotic diseases such as idiopathic pulmonary fibrosis, liver cirrhosis, systemic sclerosis, progressive kidney disease, and cardiovascular fibrosis typically target the inflammatory response, there is accumulating evidence that the mechanisms driving fibrogenesis are distinct from those regulating inflammation. In fact, some studies have suggested that ongoing inflammation is needed to reverse established and progressive fibrosis. The key cellular mediator of fibrosis is the myofibroblast, which when activated serves as the primary collagen-producing cell. Myofibroblasts are generated from a variety of sources including resident mesenchymal cells, epithelial and endothelial cells in processes termed epithelial/endothelial-mesenchymal (EMT/EndMT) transition, as well as from circulating fibroblast-like cells called fibrocytes that are derived from bone-marrow stem cells. Myofibroblasts are activated by a variety of mechanisms, including paracrine signals derived from lymphocytes and macrophages, autocrine factors secreted by myofibroblasts, and pathogen-associated molecular patterns (PAMPS) produced by pathogenic organisms that interact with pattern recognition receptors (i.e. TLRs) on fibroblasts. Cytokines (IL-13, IL-21, TGF-beta1), chemokines (MCP-1, MIP-1beta), angiogenic factors (VEGF), growth factors (PDGF), peroxisome proliferator-activated receptors (PPARs), acute phase proteins (SAP), caspases, and components of the renin-angiotensin-aldosterone system (ANG II) have been identified as important regulators of fibrosis and are being investigated as potential targets of antifibrotic drugs. This review explores our current understanding of the cellular and molecular mechanisms of fibrogenesis.
3,390 citations