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1.
Midori Hosobuchi Martha R. Stampfer 《In vitro cellular & developmental biology. Plant》1989,25(8):705-713
Summary Normal human mammary epithelial cells (HMEC) from different individual reduction mammoplasty specimens were all growth inhibited,
and showed a flattened, elongated morphology in response to human recombinant transforming growth factor β1 (TGFβ). The degree
of growth inhibition varied among specimens, but none of the normal HMEC maintained growth in the continued presence of TGFβ.
The degree of growth inhibition also varied with cell age in vitro, cells closer to senescence being more sensitive. TGFβ
sensitivity was additionally assayed in two established cell lines derived from one of the reduction mammoplasty specimens
after exposure to benzo(a)pyrene. Although varying degrees of growth inhibition and morphologic changes were observed in the
cell lines, both lines contained populations that maintained active growth in the presence of TGFβ. Subclones of these lines
demonstrated a great plasticity in their growth response to TGFβ, with individual clones ranging from strongly growth inhibited
to nearly unaffected. These results suggest that multiple factors influence the extent of TGFβ-induced growth effects on both
normal and transformed mammary epithelial cells, and that some of these factors may act through epigenetic mechanisms.
This work was supported by CA24844 from the National Institutes of Health, Bethesda, MD, and the Office of Energy Research,
Office of Health and Environmental Research of the U.S. Department of Energy under contract DE-AC03-76SF00098. 相似文献
2.
Jeon JP Hong C Park EJ Jeon JH Cho NH Kim IG Choe H Muallem S Kim HJ So I 《The Journal of biological chemistry》2012,287(21):17029-17039
The ubiquitous transient receptor potential canonical (TRPC) channels function as non-selective, Ca(2+)-permeable channels and mediate numerous cellular functions. It is commonly assumed that TRPC channels are activated by stimulation of Gα(q)-PLC-coupled receptors. However, whether the Gα(q)-PLC pathway is the main regulator of TRPC4/5 channels and how other Gα proteins may regulate these channels are poorly understood. We previously reported that TRPC4/TRPC5 can be activated by Gα(i). In the current work, we found that Gα(i) subunits, rather than Gα(q), are the primary and direct activators of TRPC4 and TRPC5. We report a novel molecular mechanism in which TRPC4 is activated by several Gα(i) subunits, most prominently by Gα(i2), and TRPC5 is activated primarily by Gα(i3). Activation of Gα(i) by the muscarinic M2 receptors or expression of the constitutively active Gα(i) mutants equally and fully activates the channels. Moreover, both TRPC4 and TRPC5 are activated by direct interaction of their conserved C-terminal SESTD (SEC14-like and spectrin-type domains) with the Gα(i) subunits. Two amino acids (lysine 715 and arginine 716) of the TRPC4 C terminus were identified by structural modeling as mediating the interaction with Gα(i2). These findings indicate an essential role of Gα(i) proteins as novel activators for TRPC4/5 and reveal the molecular mechanism by which G-proteins activate the channels. 相似文献
3.
Åke Sjöholm 《Bioscience reports》1996,16(5):415-423
The insulin-producing pancreatic islet -cell, characterized by low proliferative potential, is normally not responsive to the polypeptide epidermal growth factor (EGF) or its homolog transforming growth factor (TGF-). Since EGF receptors in other tissues can be up-regulated by other growth factors and by cytokines, we have in this paper investigated whether such a -cell responsiveness to TGF-, or EGF, can be conferred by co-culture with interferon (IFN-), tumor necrosis factor (TNF-) or transforming growth factor (TGF-) in various combinations. To this end, fetal rat pancreatic islets enriched in -cells were isolated and cultured for 3 days with or without 200 pM or 20 nM TGF-. It was found that neither of these TGF- concentrations affected -cell mitogenesis, insulin content or insulin secretion. However, IFN- (1000 U/ml) evoked a modest stimulation of -cell replication, while suppressing insulin secretion and leaving the islet insulin content unaltered. TNF- (1000 U/ml), on the other hand, affected none of these parameters either alone or in any combination with TGF- or IFN-. However, when TNF- or IFN-, either alone or in combination, were combined with the cytokine interleukin-1, this resulted in islet disintegration, whereas the latter cytokine alone did not exert any gross necrotic changes evident by light microscopy. TGF- (500 pM) stimulated insulin secretion but did not influence islet insulin content or -cell mitogenesis either alone or in combination with TGF- (200 pM or 20 nM). In no instance could any mitogenic or secretory response to low or high concentrations of TGF- be conferred by IFN-, TNF- or TGF- whether used alone or in combinations. Hence, responsiveness to TGF- or EGF in the -cell obviously cannot be achieved by any of these peptides.Abbreviations EGF
epidermal growth factor
- IFN-
interferon
- TGF-
transforming growth factor
- TGF-
transforming growth factor
- TNF-
tumor necrosis factor 相似文献
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Nadine Sommer Martin Sattler Julia M. Weise Horst Wenck Stefan Gallinat Dr. Frank Fischer 《Biotechnology journal》2013,8(3):317-326
Numerous studies have shown that extracellular matrix (ECM)-based scaffolds are suitable for dermal constructs for the differentiation of various cell types in vitro and for constructive tissue remodeling after implantation in vivo. However, a shortcoming of these ECM materials is its limited elastogenesis. Elastic fibers constitute an essential component of mammalian connective tissue and the presence of elastic fibers is crucial for the proper function of the cardiovascular, pulmonary, and intestinal systems. Since it is still largely unknown how cells coordinate the molecular events of elastic-fiber assembly, understanding the ability to regenerate elastic fibers in tissues remains a significant challenge. For this reason, human neonatal dermal fibroblasts (HDFneo) were analyzed for their potential to serve as a cell culture model for elastic fiber assembly. Using optical technologies such as multiphoton laser-scanning microscopy (MPSLM) we demonstrate that HDFneo stimulated with transforming growth factor β1 (TGF-β1) are able to produce a distinct and complex elastic fiber system in vitro. As shown by the desmosine and isodesmosine content, crosslinked elastic fibers were formed within the 3D ECM-based scaffold. This tissue-engineered dermal construct may prove to be an effective template for the development of medicinal approaches in regenerative soft skin tissue reconstruction through TGF-β1 induction. 相似文献
8.
Allan M. Ramirez Cherry Wongtrakool Teresa Welch Andreas Steinmeyer Ulrich Zügel Jesse Roman 《The Journal of steroid biochemistry and molecular biology》2010,118(3):142-150
The mechanisms that control fibroproliferation and matrix deposition in lung fibrosis remain unclear. We speculate that vitamin D deficiency may contribute to pulmonary fibrosis since vitamin D deficiency has been implicated in several diseases. First, we confirmed the presence of vitamin D receptors (VDRs) in cultured NIH/3T3 and lung fibroblasts. Fibroblasts transfected with a vitamin D response element–reporter construct and exposed to the active vitamin D metabolite, 1,25(OH)2D3, showed increased promoter activity indicating VDR functionality in these cells. Testing the effects of 1,25(OH)2D3 on fibroblasts treated with transforming growth factor β1 (TGFβ1), considered a driver of many fibrotic disorders, we found that 1,25(OH)2D3 inhibited TGFβ1-induced fibroblast proliferation in a dose-dependent fashion. 1,25(OH)2D3 also inhibited TGFβ1 stimulation of α-smooth muscle actin expression and polymerization and prevented the upregulation of fibronectin and collagen in TGFβ1-treated fibroblasts. Finally, we examined how 1,25(OH)2D3 affects epithelial–mesenchymal transformation of lung epithelial cells upon exposure to TGFβ1. We showed that the TGFβ1-induced upregulation of mesenchymal cell markers and abnormal expression of epithelial cell markers were blunted by 1,25(OH)2D3. These observations suggest that under TGFβ1 stimulation, 1,25(OH)2D3 inhibits the pro-fibrotic phenotype of lung fibroblasts and epithelial cells. 相似文献
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This study was designed to localize transforming growth factor alpha (TGF-) and epidermal growth factor receptor (EGFR) expression in the developing human gastrointestinal tract and pancreas. Immunohistochemical techniques using specific antibodies against human TGF- and EGFR were performed on digestive tissues of fetuses from 9 to 10 to 24 weeks of gestation, children and adults. In fetuses, TGF- and EGFR proteins were expressed in all epithelial tissues studied with a good correlation and from an age as early as 9 to 10 weeks of gestation, except for TGF- in the esophagus. The strongest TGF- immunostaining was noted in the stomach and the proximal colon. Unexpectedly, immunoreactive gut endocrine cells were observed with the two antibodies used. Relatively numerous in fetuses, they decreased in number with age and were rare in adults particularly along the colon. Enteroglucagon-secreting cells were shown to express TGF- while some gastrin, somatostatin and pancreatic glucagon cells were immunostained with EGFR antibodies. The presence of TGF- and of its recetor in digestive tract epithelium and pancreatic tissues early in fetal life suggests a functional role for TGF- during the developmental process of the digestive system. We demonstrate that TGF- is also produced by endocrine cells and might have an additional mode of action other than paracrine, at least during fetal life. 相似文献
11.
Ding WY Ti Y Wang J Wang ZH Xie GL Shang YY Tang MX Zhang Y Zhang W Zhong M 《The international journal of biochemistry & cell biology》2012,44(6):1031-1039
Accumulation of collagen I and III in the myocardium is a prominent feature of interstitial fibrosis. Prostaglandin F(2α) (PGF(2α)) facilitates fibrosis by increasing collagen synthesis. However, the underlying mechanisms mediating the effect of PGF(2α) on collagen expression in cardiac fibroblasts are not yet fully elucidated. We measured the mRNA and protein levels of collagen I and III by quantitative real-time PCR and ELISA, respectively. Activation of signaling pathways was determined by western blot analysis. In primary rat cardiac fibroblasts, treatment with PGF(2α) stimulated both the mRNA and protein levels of collagen I and III, and pretreatment with the F-prostanoid (FP) receptor antagonist AL-8810, protein kinase C inhibitor LY-333531, and Rho kinase inhibitor Y-27632 significantly inhibited PGF(2α)-induced collagen I and III expression. FP receptor, protein kinase C, and Rho kinase were activated with PGF(2α) treatment. PGF(2α) may be an important regulator in the synthesis of collagen I and III via an FP receptor/protein kinase C/Rho kinase cascade in cardiac fibroblasts, which might be a new therapeutic target for myocardial fibrosis. 相似文献
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To determine the role of CD24 in breast cancer cells, we knocked down CD24 in MCF-7 human breast cancer cells by retroviral delivery of shRNA. MCF-7 cells with knocked down CD24 (MCF-7 hCD24 shRNA) exhibited decreased cell proliferation and cell adhesion as compared to control MCF-7 mCD24 shRNA cells. Decreased proliferation of MCF-7 hCD24 shRNA cells resulted from the inhibition of cell cycle progression from G1 to S phase. The specific inhibition of MEK/ERK signaling by CD24 ablation might be responsible for the inhibition of cell proliferation. Phosphorylation of Src/FAK and TGF-β1-mediated epithelial to mesenchymal transition was also down-regulated in MCF-7 hCD24 shRNA cells. Reduced Src/FAK activity was caused by a decrease in integrin β1 bound with CD24 and subsequent destabilization of integrin β1. Our results suggest that down-regulation of Raf/MEK/ERK signaling via Src/FAK may be dependent on integrin β1 function and that this mechanism is largely responsible for the CD24 ablation-induced decreases in cell proliferation and epithelial to mesenchymal transition. 相似文献
13.
《Comparative biochemistry and physiology. A, Comparative physiology》1991,98(2):473-476
- 1.1. The effect of TGF-β and bFGF on lipoprotein lipase activity in chicken adipocyte precursors was investigated.
- 2.2. Lipoprotein lipase activity was reduced by up to 80% by incubation with TGF-β whereas bFGF had no effect.
- 3.3. Contrary to that found with the 3T3-L1 preadipocyte cell line it was not necessary for TGF-β to be present prior to the start of differentiation in order to be effective.
- 4.4. Incubation of adipocyte precursors with actinomycin D abolished the effect of TGF-β suggesting that synthesis of a protein effector is required.
- 5.5. These results indicate differences in responsiveness to TGF-β and bFGF between primary chicken adipocyte precursors and some preadipocyte cell lines.
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《Theriogenology》1996,45(8):1463-1472
The mammalian ovarian cycle is a strictly regulated process that is dependent on the intimate interactions among the 3 cell types in the follicle — theca, granulosa, and oocyte. The cycle has been shown to be controlled by gonadotropins as well as locally produced peptide factors. In this study, an in vitro culture system was used to study the roles of 2 locally produced ovarian peptide factors, transforming growth factor-β1 (TGF-β1) and activin-A, on porcine granulosa cell steroidogenesis. Gonadotropin stimulated cultured porcine granulosa cells (from medium-sized follicles) were pretreated with 100 ng/ml follicle-stimulating hormone (FSH) for 48 h and then treated with 1 ng/ml TGF-β1, 100 ng/ml activin-A, TGF-β1 plus activin-A, or received no treatment (control) for 48 h, From our previous studies, the concentrations of the 2 growth factors were determined to produce maximal antisteroidogenic effects in porcine granulosa cells. Progesterone (P4) production, estradiol-17β (E2) production, and aromatase activity for gonadotropin-stimulated porcine granulosa cells treated with TGF-β1, activin-A, and TGF-β1 plus activin-A were significantly (P < 0.05) reduced fromthat of the control. The same procedures were conducted on basal steroidogenesis studies in which no pretreatment with FSH was performed. Both P4 and E2 production and aromatase activity for porcine granulosa cells treated with TGF-β1, activin-A and TGF-β1 plus activin-A were significantly (P < 0.05) inhibited compared with the control. Our results indicate that both TGF-β1 and activin-A can inhibit FSH-stimulated and basal steroidogeneses in porcine granulosa cells and, thus, may act as local atretic factors during follicular development. When the 2 growth factors were given in combination at concentrations that would produce maximal steroidogenic inhibition, they were not able to produce a synergistic effect. These results are consistent with the current theory that TGF-β1 and activin-A may act via the same messenger system, a serine-threonine kinase. 相似文献
16.
Young-Rak Cho Jin-Kyu Kim Jae Hyeon Kim Joa Sub Oh Dong-Wan Seo 《Genes & genomics.》2013,35(6):741-746
In the present study, we report the effect and molecular mechanism of Ligularia fischeri (LF) on proliferation and migration in human lung cancer cells. LF-mediated inhibition of cell proliferation in p53 wild-type A549 and p53-deficient H1299 cells is accompanied by reduced expression of cell cycle-related proteins such as cyclin-dependent kinases and cyclins, resulting in pRb hypophosphorylation and G1 phase cell cycle arrest. In contrast, LF inhibits cell migration in A549 cells, but not in H1299 cells. These regulatory effects of LF on cell proliferation and migration are associated with inactivation of mitogenic signaling pathways such as ERK, Akt and p70S6K, and down-regulation of epidermal growth factor receptor and integrin β1 expression. Collectively, these findings suggest further development and evaluation of LF for the prevention and treatment of lung cancer with mutated p53 as well as wild-type p53. 相似文献
17.
Shanlong Huang Delai Fu Ziyan Wan Min Li Hecheng Li Tie Chong 《Journal of cellular and molecular medicine》2021,25(18):8796-8808
Urethral stricture (US) is a common disorder of the lower urinary tract in men caused by fibrosis. The recurrence rate of US is high; however, there are no effective therapies to prevent or treat urethral fibrosis. The pathogenesis of urethral fibrosis involves myofibroblast activation and excessive extracellular matrix (ECM) deposition. The molecular mechanisms underlying this pathological activation are not completely understood. It has been demonstrated that Notch signalling contributes to the development of fibrosis and inflammation. However, whether this contributes to urethral fibrosis remains unclear. In this study, activation of Notch signalling was observed in patients with US. Additionally, it was noted that activation of Notch signalling promoted ECM production and myofibroblast activation in human urethral scar fibroblasts (HUSFs) treated with transforming growth factor (TGF) β1. However, the Notch inhibitor N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (DAPT) suppressed activation of Notch signalling as well as proliferation and migration of the TGFβ1-treated HUSFs. Additionally, DAPT ameliorated TGFβ1-induced urethral fibrosis in Sprague Dawley rats by suppressing ECM production, myofibroblast activation and the TGFβ signalling pathway. These findings demonstrate that Notch signalling may be a promising and potential target in the prevention or treatment of urethral fibrosis. 相似文献
18.
Xu Q Isaji T Lu Y Gu W Kondo M Fukuda T Du Y Gu J 《The Journal of biological chemistry》2012,287(20):16563-16574
The epithelial-to-mesenchymal transition (EMT) plays crucial roles in embryonic development, wound healing, tissue repair, and cancer progression. Results of this study show how transforming growth factor β1 (TGF-β1) down-regulates expression of N-acetylglucosaminyltransferase III (GnT-III) during EMT-like changes. Treatment with TGF-β1 resulted in a decrease in E-cadherin expression and GnT-III expression, as well as its product, the bisected N-glycans, which was confirmed by erythro-agglutinating phytohemagglutinin lectin blot and HPLC analysis in human MCF-10A and mouse GE11 cells. In contrast with GnT-III, the expression of N-acetylglucosaminyltransferase V was slightly enhanced by TGF-β1 treatment. Changes in the N-glycan patterns on α3β1 integrin, one of the target proteins for GnT-III, were also confirmed by lectin blot analysis. To understand the roles of GnT-III expression in EMT-like changes, the MCF-10A cell was stably transfected with GnT-III. It is of particular interest that overexpression of GnT-III influenced EMT-like changes induced by TGF-β1, which was confirmed by cell morphological changes of phase contrast, immunochemical staining patterns of E-cadherin, and actin. In addition, GnT-III modified E-cadherin, which served to prolong E-cadherin turnover on the cell surface examined by biotinylation and pulse-chase experiments. GnT-III expression consistently inhibited β-catenin translocation from cell-cell contact into the cytoplasm and nucleus. Furthermore, the transwell assay showed that GnT-III expression suppressed TGF-β1-induced cell motility. Taken together, these observations are the first to clearly demonstrate that GnT-III affects cell properties, which in turn influence EMT-like changes, and to explain a molecular mechanism for the inhibitory effects of GnT-III on cancer metastasis. 相似文献
19.
Felicia L. Cianciarulo Paul D. Phillips Vincent J. Cristofalo 《In vitro cellular & developmental biology. Animal》1993,29(8):656-660
Summary Tumor necrosis factor-α (TNF) and various interferons (IFN) have potent cytostatic or cytotoxic effects on a variety of human
tumor-derived cell lines. Their effects on normal cells are more controversial. We have examined the effects of TNF and IFN-β
on the proliferation of WI-38 cells in a serum-free, growth factor-supplemented medium and in serum-containing medium. These
cells respond to the combination of epidermal growth factor (EGF), insulin-like growth factor-I (IGF-I), and dexamethasone
by DNA synthesis at a rate and extent equivalent to serum-stimulated cells. TNF has no effect on this growth factor-stimulated
proliferation. However, it is stimulatory in serum-containing medium. IFN-β inhibits DNA synthesis 60 to 70% in both young
and senescent cells. TNF and IFN-β together have a synergistic effect and completely inhibit growth factor-stimulated DNA
synthesis in young cells. No synergism was observed with senescent cells. TNF stimulated an increase in the number of EGF
specific binding sites two- to threefold in 24 h in both young and senescent cells. This seems to result from a proportional
increase in a very high affinity binding site. IFN-β has little or no effect on EGF binding either alone or in combination
with TNF. 相似文献
20.
The transforming growth factor type III receptor (TβRIII), also known as β-glycan, is a multi-functional sensor that regulates growth, migration and apoptosis in most cancer cells. We hereby investigated the expression of TβRIII in clinical specimens of tongue squamous cell carcinoma (TSCC) and the underlying mechanism that TβRIII inhibits the growth of CAL-27 human oral squamous cells. The TSCC tissues showed a significant decrease in TβRIII protein expression as detected by immunohistochemistry (IHC) and western blot analysis. Transfection of TβRIII-containing plasmid DNA dramatically promoted TGF-β1 (10 ng/ml)-induced decrease in cell viability, apoptosis and cell arrest at the G0-/G1-phase. Moreover, transient overexpression of TβRIII enhanced the TGF-β1-induced cyclin-dependent kinase inhibitor 2b (CDKN2b) and p38 protein activity, but did not affect the activities of extracellular signal-regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase 1/2 (JNK1/2) in CAL-27 cells. These results suggest overexpression of TβRIII receptor restored TGF-β1 sensitivity in CAL-27 cells, which may provide some new insights on exploiting this molecule therapeutically. 相似文献