Maspin is physically associated with 1 integrin regulating cell adhesion in mammary epithelial cells

Baylor College of Medicine, Department of Molecular and Cellular Biology, ALKEK Bldg., Rm. N630, One Baylor Plaza, Houston, Texas 77030, USA.
The FASEB Journal (Impact Factor: 5.04). 08/2006; 20(9):1510-2. DOI: 10.1096/fj.05-5500fje
Source: PubMed


Maspin is a tumor-suppressor serpin (serine protease inhibitor), which inhibits cell invasion and migration. Here, we analyzed maspin function in cell adhesion in nontransformed mammary epithelial cells and investigated the underlying mechanism involved in this process. We report that maspin acts in the early steps in the cell adhesion process. Addition of recombinant maspin rapidly increased MCF-10A cell adhesion to the endogenously deposited matrix, and conversely both an antimaspin antibody (Ab) and maspin knockdown by RNA interference resulted in decreased cell adhesion. Mutation analyses revealed that a region of 86 amino acids located between aa 139 and aa 225 was responsible for maspin effect on adhesion. In addition, we show that maspin is associated with detergent-insoluble cortical cytoskeleton elements. Collectively, these results suggest that maspin is part of the supramolecular structure of the adhesion plaque and it modulates cell adhesion via a beta1 integrin-dependent mechanism.

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Available from: Khatri Latha, Mar 17, 2014
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    • "Parasite strain and cell culture T. cruzi Y strain was used throughout and was grown and maintained as described by Andrews and Colli (1982). MCF- 10A human mammary cells (purchased from BCRJ/UFRJ) were cultivated as monolayers in Dulbecco's modified Eagle's medium (DMEM)/F12 (Life Technologies) containing 20 % donor horse serum, 20 ng/ml epidermal growth factor (EGF), 100 ng/ml cholera toxin, 10 ng/ml insulin, 500 ng/ml hydrocortisone , 50 U/ml penicillin, and 50 μg/ml streptomycin at 37 °C and 5 % CO 2 in a humidified air atmosphere (Cella et al. 2006). The membrane-enriched fraction was obtained by treatment of 5 × 10 7 MCF-10A cells with lysis buffer (20 mM Tris-HCl, pH 7.5, 2 mM EDTA, 10 mM EGTA, 0.25 mM sucrose, protease inhibitor cocktail (Sigma-Aldrich), and centrifugation at 100,000g for 40 min. "
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    Parasitology Research 10/2014; 114(1). DOI:10.1007/s00436-014-4172-6 · 2.10 Impact Factor
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    • "It is possible that extracellular maspin directly effects cell migration, adhesion and angiogenesis, while indirectly effecting tumour cell proliferation and apoptosis. Maspin has been reported to bind to integrin cell adhesion receptors (Cella et al., 2006; Bass et al., 2009) or to the ECM (Blacque, and Worrall, 2002). Intracellular maspin binding partners have been identified, including the transcription factor IRF-6 (Biliran and Sheng, 2001; Bailey et al., 2005), and histone deacetylase 1 influencing the Bcl-2/Bax signal axis (Li et al., 2005; Li et al., 2006). "
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    ABSTRACT: Cancer metastasis is a complex multistep process which allows cancer cells to establish new tumours in distant organs. The process of metastasis involves cell migration and invasion; it is what makes cancer a fatal disease. The efficiency of most cancer treatments depends on metastasis suppression. Maspin is a type II tumour metastasis suppressor which has multiple cellular effects. It has been described as a key regulatory protein in both the intracellular and extracellular environments. Maspin has been shown to reduce cell migration, invasion, proliferation and angiogenesis, and increase apoptosis and cell-cell adhesion in in vitro and in vivo experiments. The clinical data regarding the predictive effects of maspin expression are variable. To date, the whole cellular mechanisms that maspin uses to influence tumour cell behaviours have not been clearly defined. The diversity of the effects of maspin motivated us to develop an intelligent model to investigate its effects on cellular proliferation and migration. This paper reports a hybrid model of solid tumour growth in order to investigate the impact of maspin on the growth and evolutionary dynamics of the cancer cell. A feed-forward neural network was used to model the behaviours (proliferation, quiescence, apoptosis and/or movement) of each cell, which has been suggested as a suitable model of cell signalling pathways. Results show that maspin reduces migration by 10-40%, confirmed by published in vitro data. The model also shows a reduction in cell proliferation by 20-30% in the presence of maspin. So far, this is the first attempt to model the effect of maspin in a computational model to verify in vitro data. This will provide new insights into the tumour suppressive properties of maspin and inform the development of novel cancer therapies.
    Journal of Theoretical Biology 08/2013; 337. DOI:10.1016/j.jtbi.2013.08.016 · 2.12 Impact Factor
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    • "Therefore, we suspect maspin tyrosine phosphoforms are not efficiently immunoprecipitated by the commercially available maspin antibodies. Since maspin is present in multiple cellular compartments and it is also detected in the Triton X-100 insoluble cytoskeleton fraction [6], cells lysates were prepared in a strongly denaturing and chaotropic solution containing 8 M urea (see Section 2), to reassure that maspin associated with the different cellular components would be extracted . However, this extraction solution precludes the phosphatase treatment of the extract. "
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    FEBS Open Bio 12/2012; 2:93-7. DOI:10.1016/j.fob.2012.04.006 · 1.52 Impact Factor
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