Identification and testing of a gene expression signature of invasive carcinoma cells within primary mammary tumors

Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
Cancer Research (Impact Factor: 9.33). 01/2005; 64(23):8585-94. DOI: 10.1158/0008-5472.CAN-04-1136
Source: PubMed


We subjected cells collected using an in vivo invasion assay to cDNA microarray analysis to identify the gene expression profile of invasive carcinoma cells in primary mammary tumors. Expression of genes involved in cell division, survival, and cell motility were most dramatically changed in invasive cells indicating a population that is neither dividing nor apoptotic but intensely motile. In particular, the genes coding for the minimum motility machine that regulates beta-actin polymerization at the leading edge and, therefore, the motility and chemotaxis of carcinoma cells, were dramatically up-regulated. However, ZBP1, which restricts the localization of beta-actin, the substrate for the minimum motility machine, was down-regulated. This pattern of expression implicated ZBP1 as a suppressor of invasion. Reexpression of ZBP1 in metastatic cells with otherwise low levels of ZBP1 reestablished normal patterns of beta-actin mRNA targeting and suppressed chemotaxis and invasion in primary tumors. ZBP1 reexpression also inhibited metastasis from tumors. These experiments support the involvement in metastasis of the pathways identified in invasive cells, which are regulated by ZBP1.

Download full-text


Available from: Sumanta Goswami,
23 Reads
  • Source
    • "Thus, to facilitate analysis of the mechanism of Mena INV dependent growth factor sensitization, we used human cell lines that ectopically express GFP- Mena, GFP-Mena INV , or GFP alone. Mena was found to be upregulated approximately 10-fold at the RNA level in invasive tumor cells collected from primary xenograft tumors, therefore we engineered our cells to express levels roughly comparable to those seen in invasive cells from primary tumors (Wang et al., 2004) (Fig S1). As expected, Mena INV -expressing cells invaded further into 3D collagen gels (Fig 1A). "
    [Show abstract] [Hide abstract]
    ABSTRACT: During breast cancer progression, alternative mRNA splicing produces functionally distinct isoforms of Mena, an actin regulator with roles in cell migration and metastasis. Aggressive tumor cell subpopulations express Mena(INV), which promotes tumor cell invasion by potentiating EGF responses. However, the mechanism by which this occurs remains unknown. Here, we report that Mena associates constitutively with the tyrosine phosphatase PTP1B and mediates a novel negative feedback mechanism that attenuates receptor tyrosine kinase signaling. On EGF stimulation, complexes containing Mena and PTP1B are recruited to the EGFR, causing receptor dephosphorylation and leading to decreased motility responses. Mena also interacts with the 5' inositol phosphatase SHIP2, which is important for the recruitment of the Mena-PTP1B complex to EGFR. When Mena(INV) is expressed, PTP1B recruitment to EGFR is impaired, providing a mechanism for growth factor sensitization to EGF, as well as HGF and IGF, and increased resistance to EGFR and Met inhibitors in signaling and motility assays. In sum, we demonstrate that Mena plays an important role in regulating growth factor-induced signaling. Disruption of this attenuation by Mena(INV) sensitizes tumor cells to low growth factor concentrations, thereby increasing the migration and invasion responses that contribute to aggressive, malignant cell phenotypes. © 2015 by The American Society for Cell Biology.
    Molecular biology of the cell 09/2015; DOI:10.1091/mbc.E15-06-0442 · 4.47 Impact Factor
  • Source
    • "However, there are still promising candidates such as MT1-MMP (Chen et al., 1994; Chen, 1996; Sabeh et al., 2009). In addition, upstream players that induce invadopodia formation such as Mena INV , Arg, IL-6, EGFR, and faciogenital dysplasia protein Fgd1, are known to have increased expression levels in various cancers (Ayala et al., 2009; Clark et al., 2009; Li et al., 2010b; Wang et al., 2004, 2007; Gil-Henn et al., 2013). Thus both upstream regulators and structural components of invadopodia present vital opportunities for diagnosis and therapy. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The leading cause of death in cancer patients is metastasis. Invasion is an integral part of metastasis and is carried out by proteolytic structures called invadopodia at the cellular level. In this introductory review, we start by evaluating the definition of invadopodia. While presenting the upstream signaling events involved, we integrate current models on invadopodia. In addition, we discuss the significance of invadopodia in 2D and 3D and in vivo. We finally point out technical challenges and conclude with open questions in the field.
    Turkish Journal of Biology 11/2014; 38(6):740-747. DOI:10.3906/biy-1404-110 · 1.34 Impact Factor
  • Source
    • "Several actin binding proteins are deregulated in cancer cell lines [28], [52], among them Profilin (PfnI), which was proposed as a tumor suppressor protein [27], [30]. PfnI expression levels are significantly down-regulated in various types of adenocarcinoma cells. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Cellular motility is the basis for cancer cell invasion and metastasis. In the case of breast cancer, the most common type of cancer among women, metastasis represents the most devastating stage of the disease. The central role of cellular motility in cancer development emphasizes the importance of understanding the specific mechanisms involved in this process. In this context, tumor development and metastasis would be the consequence of a loss or defect of the mechanisms that control cytoskeletal remodeling. Profilin I belongs to a family of small actin binding proteins that are thought to assist in actin filament elongation at the leading edge of migrating cells. Traditionally, Profilin I has been considered to be an essential control element for actin polymerization and cell migration. Expression of Profilin I is down-regulated in breast and various other cancer cells. In MDA-MB-231 cells, a breast cancer cell line, further inhibition of Profilin I expression promotes hypermotility and metastatic spread, a finding that contrasts with the proposed role of Profilin in enhancing polymerization. In this report, we have taken advantage of the fluorescence recovery after photobleaching (FRAP) of GFP-actin to quantify and compare actin dynamics at the leading edge level in both cancer and non-cancer cell models. Our results suggest that (i) a high level of actin dynamics (i.e., a large mobile fraction of actin filaments and a fast turnover) is a common characteristic of some cancer cells; (ii) actin polymerization shows a high degree of independence from the presence of extracellular growth factors; and (iii) our results also corroborate the role of Profilin I in regulating actin polymerization, as raising the intracellular levels of Profilin I decreased the mobile fraction ratio of actin filaments and slowed their polymerization rate; furthermore, increased Profilin levels also led to reduced individual cell velocity and directionality.
    PLoS ONE 01/2014; 9(1):e85817. DOI:10.1371/journal.pone.0085817 · 3.23 Impact Factor
Show more