Fibulin-5 initiates epithelial-mesenchymal transition (EMT) and enhances EMT induced by TGF- in mammary epithelial cells via a MMP-dependent mechanism

Department of Pharmacology, University of Colorado Health Sciences Center, Aurora, CO 80045, USA.
Carcinogenesis (Impact Factor: 5.33). 09/2008; 29(12):2243-51. DOI: 10.1093/carcin/bgn199
Source: PubMed


Epithelial-mesenchymal transition (EMT) is a normal physiological process that regulates tissue development, remodeling and repair; however, aberrant EMT also elicits disease development in humans, including lung fibrosis, rheumatoid arthritis and cancer cell metastasis. Transforming growth factor-beta (TGF-beta) is a master regulator of EMT in normal mammary epithelial cells (MECs), wherein this pleiotropic cytokine also functions as a potent suppressor of mammary tumorigenesis. In contrast, malignant MECs typically evolve resistance to TGF-beta-mediated cytostasis and develop the ability to proliferate, invade and metastasize when stimulated by TGF-beta. It therefore stands to reason that establishing how TGF-beta promotes EMT may offer new insights into targeting the oncogenic activities of TGF-beta in human breast cancers. By monitoring alterations in the actin cytoskeleton and various markers of EMT, we show here that the TGF-beta gene target, fibulin-5 (FBLN5), initiates EMT and enhances that induced by TGF-beta. Whereas normal MECs contain few FBLN5 transcripts, those induced to undergo EMT by TGF-beta show significant upregulation of FBLN5 messenger RNA, suggesting that EMT and the dedifferentiation of MECs override the repression of FBLN5 expression in polarized MECs. We also show that FBLN5 stimulated matrix metalloproteinase expression and activity, leading to MEC invasion and EMT, to elevated Twist expression and to reduced E-cadherin expression. Finally, FBLN5 promoted anchorage-independent growth in normal and malignant MECs, as well as enhanced the growth of 4T1 tumors in mice. Taken together, these findings identify a novel EMT and tumor-promoting function for FBLN5 in developing and progressing breast cancers.

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    • "The network through JnK as central regulator shows a probable mechanism of EMT through sequential regulation Snai2, Tgfbr3, Twist1, and Fbln5 which can directly interact with Loxl1 [21] (Fig. 2C). Fbln5 (Fibulin-5) has been shown to initiate and enhance EMT already induced by Tgf-β [22]. In all it is clear that the in vitro generated ILCs retain some mesenchymal characteristics as reported before in case of human islets expanded in vitro [23] [24]. "
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    ABSTRACT: We have earlier reported the generation of islet-like clusters (ILCs) from mesenchymal stromal cell (MSC)-like cells present in murine pancreas. Here we compare these ILCs to native primary islets by transcriptome screening. Genes were categorized into functional clusters and network analysis was done by Ingenuity Pathway Analysis (IPA). The fold changes for a selected panel of molecules were validated with quantitative real time PCR. A differential expression of 6516 genes (p-value≤0.05, 1.5 fold change) with upregulated expression of numerous inflammatory and 'Epithelial to Mesenchymal Transition' molecules (EMT) was seen. A significant increase in the early β-cell marker expression in the ILCs indicated their progenitor status. Although not fully mature, ILCs offer certain advantages including the large number of easily inducible initiator MSCs. These 'naïve' cells may aid to devise protocols for generating functional islet equivalents. Moreover their maturation upon transplantation under local microenvironmental niche is highly possible.
    Genomics 01/2015; DOI:10.1016/j.ygeno.2015.01.003. · 2.28 Impact Factor
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    • "Moreover, our data also suggest that Twist protein expression is positively associated with gelatinase expression in breast cancer. Lee et al (24) identified that EMT is induced by transforming growth factor (TGF)-β and Twist in mammary epithelial cells via a MMP-dependent mechanism. Yu et al (25) explored the functions of Twist in hypopharyngeal cancer tissue samples by IHC assays and the results indicated that alteration of Twist has an effect on EMT, c-fos and MMP-9 expression. "
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    ABSTRACT: Altered expression of Twist, matrix metalloproteinase (MMP)-2 and MMP-9 proteins has been identified in various types of human cancers. However, the correlation between Twist and these gelatinases in breast cancer remains unclear. In this study, immunohistochemical analysis of Twist, MMP-2 and MMP-9 expression was performed on tissue microarrays from 200 breast cancer cases. The association of Twist and gelatinase expression with clinicopathological factors and patient survival was analyzed. Altered expression of Twist, MMP-2 and MMP-9 proteins was observed in breast cancer tissue. The positive rates of Twist, MMP-2 and MMP-9 protein expression were 75.5, 97.0 and 96.0%, respectively. Increased expression of Twist was positively correlated with the status of axillary lymph node metastasis and higher tumor-node-metastasis (TNM) stage (P<0.01). Moreover, increased expression of Twist was correlated with poor overall survival (OS) and post-operative relapse-free survival (RFS), compared with those for the patients with reduced expression levels of Twist (P<0.05, P<0.01). The expression of MMP-2 and MMP-9 was positively correlated with Twist expression (P<0.001). Our results indicate that Twist may play an important role in the invasion, metastasis and prognosis of breast cancer. Additionally, our results suggest that Twist may be a regulator of gelatinases (MMP-2 and MMP-9).
    Experimental and therapeutic medicine 07/2013; 6(1):97-100. DOI:10.3892/etm.2013.1099 · 1.27 Impact Factor
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    • "Paraffin sections were stained with hematoxylin and eosin (H&E) (Sigma). For immunohistochemistry, immunostaining of E-cadherin and vimentin was carried out using a standard protocol [29]. The H&E sections were evaluated and photographed with a Nikon Eclipse 50i microscope controlled by the NIS-Elements software (version 3.22). "
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    ABSTRACT: Metastasis is the major cause of cancer related death and targeting the process of metastasis has been proposed as a strategy to combat cancer. Therefore, to develop candidate drugs that target the process of metastasis is very important. In the preliminary studies, we found that schisandrin B (Sch B), a naturally-occurring dibenzocyclooctadiene lignan with very low toxicity, could suppress cancer metastasis. BALB/c mice were inoculated subcutaneously or injected via tail vein with murine breast cancer 4T1 cells. Mice were divided into Sch B-treated and control groups. The primary tumor growth, local invasion, lung and bone metastasis, and survival time were monitored. Tumor biopsies were examined immuno- and histo-pathologically. The inhibitory activity of Sch B on TGF-β induced epithelial-mesenchymal transition (EMT) of 4T1 and primary human breast cancer cells was assayed. Sch B significantly suppressed the spontaneous lung and bone metastasis of 4T1 cells inoculated s.c. without significant effect on primary tumor growth and significantly extended the survival time of these mice. Sch B did not inhibit lung metastasis of 4T1 cells that were injected via tail vein. Delayed start of treatment with Sch B in mice with pre-existing tumors did not reduce lung metastasis. These results suggested that Sch B acted at the step of local invasion. Histopathological evidences demonstrated that the primary tumors in Sch B group were significantly less locally invasive than control tumors. In vitro assays demonstrated that Sch B could inhibit TGF-β induced EMT of 4T1 cells and of primary human breast cancer cells. Sch B significantly suppresses the lung and bone metastasis of 4T1 cells via inhibiting EMT, suggesting its potential application in targeting the process of cancer metastasis.
    PLoS ONE 07/2012; 7(7):e40480. DOI:10.1371/journal.pone.0040480 · 3.23 Impact Factor
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