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Partha Roy - One of the best experts on this subject based on the ideXlab platform.
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Abstract 4941: Profilin-1 is a key determinant for tumorigenic potential of breast cancer cells
Molecular and Cellular Biology, 2015Co-Authors: Chang Jiang, Zhijie Ding, Marion Joy, Laura L. Vollmer, David Gau, Su Hyeong Kim, Shivendra V. Singh, Andreas Vogt, Partha RoyAbstract:A hallmark of oncogenic transformation is disruption of the actin cytoskeleton, which is partly attributed to altered expression and/or activity of proteins that bind to and regulate the state of polymerization of actin in cells. Profilin-1 (Pfn1) is a key regulator of actin polymerization that is downregulated in human breast cancer, and reduced Pfn1 levels were shown to facilitate dissemination-promoting activities of certain types of breast cancer cells. The objective of the present study was to investigate whether Pfn1 modulation affects tumor initiating capacity of breast cancer cells. Using a MMTV-PyMT transgenic mouse model, we demonstrated that mice engineered for conditional Cre-mediated homozygous deletion of Pfn1 (Pfn1−/−) in the mammary gland develop fewer spontaneous mammary tumors and exhibit longer survival than either wild-type or heterozygous Pfn1-knockout littermates. Haplo-insufficiency of Pfn1 (Pfn1+/−) causes the expected ∼50% downregulation of Pfn1 expression in tumors; however, mammary tumors isolated from Pfn1−/− mice exhibit residual Pfn1 expression that is at least comparable to the level found in tumors derived from Pfn1+/− mice. This scenario is consistent with a competitive disadvantage of Pfn1-null tumor cells for autonomous growth and/or survival, allowing selective outgrowth of tumor cell populations that have incomplete Cre-mediated gene excision of Pfn1, likely resulting from mosaic activation of Cre-driving MMTV-promoter in mammary gland. Acute deletion of floxed-Pfn1 alleles in normal mouse mammary epithelial cells by Cre-adenovirus transduction dramatically impairs their ability to outgrow when seeded sparsely on 3D matrigel. Likewise, human breast cancer cells exhibit retarded outgrowth on 3D matrigel upon stable silencing of Pfn1 expression even though their proliferation on 2D tissue-culture substrate was not affected. Correlated with these phenotypic changes, Pfn1 knockdown suppresses stem-cell-like behavior of breast cancer cells as marked by a significant reduction in both aldehyde dehydrogenase activity and mammosphere forming ability. Collectively, these findings suggest that a minimum level of Pfn1 is essential for tumor initiation of breast cancer cells. Interestingly, the outgrowth-deficient phenotype of Pfn1-depleted breast cancer cells on 3D-matrigel can be fully rescued by addition of collagen-I which suggests that alteration in cell-matrix adhesion and downstream signaling underlies the growth-related phenotypic changes induced by loss of Pfn1. Finally, the outgrowth-deficient phenotype of breast cancer cells can also be elicited in vitro and in vivo by Pfn1 overexpression, further suggesting that an optimum range of Pfn1 expression is conducive for tumor-initiating capacity of breast cancer cells. Based on these results, we conclude that Pfn1 expression level is a major determinant for tumorigenic potential of breast cancer cells. Citation Format: Chang Jiang, Zhijie Ding, Marion Joy, Laura Vollmer, Dave Gau, Su Hyeong Kim, Shivendra Singh, Andreas Vogt, Partha Roy. Profilin-1 is a key determinant for tumorigenic potential of breast cancer cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4941. doi:10.1158/1538-7445.AM2015-4941
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Abstract 1325: Profilin-1 overexpression downregulates phosphorylation of p27kip1 leading to its nuclear accumulation in breast cancer cells
Molecular and Cellular Biology, 2014Co-Authors: Chang Jiang, William Veon, Partha RoyAbstract:Profilin-1 is a ubiquitously expressed actin-binding protein that is downregulated in human breast cancer. Overexpression of Profilin-1 in human breast cancer cells suppresses their tumorigenic potential. We had previously shown that Profilin-1 overexpression elevates the expression level of p27kip1 leading to cell-cycle arrest in G1 phase. In the present work, we explore the underlying mechanism. Our studies showed that Profilin-1-induced accumulation of p27kip1 in breast cancer cells occurs most dramatically in the nuclear compartment and this is due to impaired protein degradation. Consistent with these observations, we found that phosphorylation of p27kip1 at T187 (a prerequisite for p27kip1 degradation by SCF-Skp2 complex in the nucleus) and S10 (a post-translational event that promotes nuclear export of p27kip1) residues are both significantly inhibited by Profilin-1 overexpression. Elevating Profilin-1 level suppresses AKT activation, and hyper-activating AKT through overexpression of a constitutively active mutant relieves Profilin-1-induced inhibition of T187 phosphorylation and elevation of p27kip1. These data demonstrate that Profilin-1 can control the cellular level of p27kip1 in breast cancer cells through affecting its post-translational modification in an AKT-dependent pathway. These findings may provide mechanistic insights underlying the tumor-suppressive action of Profilin-1. Citation Format: Chang Jiang, William Veon, Partha Roy. Profilin-1 overexpression downregulates phosphorylation of p27kip1 leading to its nuclear accumulation in breast cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1325. doi:10.1158/1538-7445.AM2014-1325
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Profilin-1 versus Profilin-2: two faces of the same coin?
Breast cancer research : BCR, 2013Co-Authors: Zhijie Ding, Partha RoyAbstract:Proteins belonging to the Profilin family of actin-binding proteins are considered to be important control elements for actin polymerization and have been linked to a broad spectrum of cellular functions, including cell migration. An intriguing paper recently published in Cancer Cell unveils differential effects of Profilin-1 and Profilin-2, the two major isoforms of Profilin, on actin cytoskeletal regulation, motility, and invasion of breast cancer cells, and further establishes a mechanism underlying Profilin-2's suppressive effect on breast cancer cell migration. This viewpoint discusses the implications of these findings in the context of how Profilins might regulate breast cancer cell motility.
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Molecular insights on context-specific role of Profilin-1 in cell migration
Cell adhesion & migration, 2012Co-Authors: Zhijie Ding, Yongho Bae, Partha RoyAbstract:Profilin-1 (Pfn1) is a ubiquitously expressed actin-monomer binding protein that has been linked to many cellular activities ranging from control of actin polymerization to gene transcription. Traditionally, Pfn1 has been considered to be an essential control element for actin polymerization and cell migration. Seemingly contrasting this view, a few recent studies have shown evidence of an inhibitory action of Pfn1 on motility of certain types of carcinoma cells. In this review, we summarize biochemistry and functional aspects of Pfn1 in normal cells and bring in newly emerged action of Pfn1 in cancer cells that may explain its context-specific role in cell migration.
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Profilin 1 overexpression inhibits proliferation of mda mb 231 breast cancer cells partly through p27kip1 upregulation
Journal of Cellular Physiology, 2010Co-Authors: Li Zou, Zhijie Ding, Partha RoyAbstract:Profilin-1 (Pfn1), a ubiquitously expressed actin-binding protein, has gained interest in epithelial-derived cancer because of its downregulation in expression in various adenocarcinoma. Pfn1 overexpression impairs tumorigenic ability of human breast cancer xenografts thus suggesting that Pfn1 could be a tumor-suppressor protein. The objective of the present study was to determine how Pfn1 overexpression affects cell-cycle progression of breast cancer cells. We show that Pfn1 overexpression in MDA-MB-231 breast cancer cells causes cell-cycle arrest in G1 phase and dramatically reduced proliferation in culture. Pfn1 overexpression results in increased protein stability of p27(kip1) (p27-a major cyclin-dependent kinase inhibitor) and marked elevation in the overall cellular level of p27. Proliferation defect of Pfn1 overexpressers can be partly rescued by silencing p27 expression thus suggesting a critical role of p27 in Pfn1-induced growth inhibition of MDA-MB-231 cells. Finally, Pfn1 overexpression was found to sensitize MDA-MB-231 cells to apoptosis in response to cytotoxic stimulus thus suggesting for the first time that survival of breast cancer cells can also be negatively influenced by Pfn1 upregulation. These findings may provide novel insights underlying Pfn1's tumor-suppressive action.
Andrius Kazlauskas - One of the best experts on this subject based on the ideXlab platform.
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Profilin-1 Is Expressed in Human Atherosclerotic Plaques and Induces Atherogenic Effects on Vascular Smooth Muscle Cells
PloS one, 2010Co-Authors: Evren Caglayan, Giulio R. Romeo, Kai Kappert, Margarete Odenthal, Michael Sudkamp, Simon C Body, Stanton K Shernan, Daniel Hackbusch, Marius Vantler, Andrius KazlauskasAbstract:Background Profilin-1 is an ubiquitous actin binding protein. Under pathological conditions such as diabetes, Profilin-1 levels are increased in the vascular endothelium. We recently demonstrated that Profilin-1 overexpression triggers indicators of endothelial dysfunction downstream of LDL signaling, and that attenuated expression of Profilin-1 confers protection from atherosclerosis in vivo. Methodology Here we monitored Profilin-1 expression in human atherosclerotic plaques by immunofluorescent staining. The effects of recombinant Profilin-1 on atherogenic signaling pathways and cellular responses such as DNA synthesis (BrdU-incorporation) and chemotaxis (modified Boyden-chamber) were evaluated in cultured rat aortic and human coronary vascular smooth muscle cells (VSMCs). Furthermore, the correlation between Profilin-1 serum levels and the degree of atherosclerosis was assessed in humans. Principal Findings In coronary arteries from patients with coronary heart disease, we found markedly enhanced Profilin expression in atherosclerotic plaques compared to the normal vessel wall. Stimulation of rat aortic and human coronary VSMCs with recombinant Profilin-1 (10−6 M) in vitro led to activation of intracellular signaling cascades such as phosphorylation of Erk1/2, p70S6 kinase and PI3K/Akt within 10 minutes. Furthermore, Profilin-1 concentration-dependently induced DNA-synthesis and migration of both rat and human VSMCs, respectively. Inhibition of PI3K (Wortmannin, LY294002) or Src-family kinases (SU6656, PP2), but not PLCγ (U73122), completely abolished Profilin-induced cell cycle progression, whereas PI3K inhibition partially reduced the chemotactic response. Finally, we found that Profilin-1 serum levels were significantly elevated in patients with severe atherosclerosis in humans (p
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Profilin 1 is expressed in human atherosclerotic plaques and induces atherogenic effects on vascular smooth muscle cells
PLOS ONE, 2010Co-Authors: Evren Caglayan, Giulio R. Romeo, Kai Kappert, Margarete Odenthal, Michael Sudkamp, Simon C Body, Stanton K Shernan, Daniel Hackbusch, Marius Vantler, Andrius KazlauskasAbstract:Background Profilin-1 is an ubiquitous actin binding protein. Under pathological conditions such as diabetes, Profilin-1 levels are increased in the vascular endothelium. We recently demonstrated that Profilin-1 overexpression triggers indicators of endothelial dysfunction downstream of LDL signaling, and that attenuated expression of Profilin-1 confers protection from atherosclerosis in vivo. Methodology Here we monitored Profilin-1 expression in human atherosclerotic plaques by immunofluorescent staining. The effects of recombinant Profilin-1 on atherogenic signaling pathways and cellular responses such as DNA synthesis (BrdU-incorporation) and chemotaxis (modified Boyden-chamber) were evaluated in cultured rat aortic and human coronary vascular smooth muscle cells (VSMCs). Furthermore, the correlation between Profilin-1 serum levels and the degree of atherosclerosis was assessed in humans. Principal Findings In coronary arteries from patients with coronary heart disease, we found markedly enhanced Profilin expression in atherosclerotic plaques compared to the normal vessel wall. Stimulation of rat aortic and human coronary VSMCs with recombinant Profilin-1 (10−6 M) in vitro led to activation of intracellular signaling cascades such as phosphorylation of Erk1/2, p70S6 kinase and PI3K/Akt within 10 minutes. Furthermore, Profilin-1 concentration-dependently induced DNA-synthesis and migration of both rat and human VSMCs, respectively. Inhibition of PI3K (Wortmannin, LY294002) or Src-family kinases (SU6656, PP2), but not PLCγ (U73122), completely abolished Profilin-induced cell cycle progression, whereas PI3K inhibition partially reduced the chemotactic response. Finally, we found that Profilin-1 serum levels were significantly elevated in patients with severe atherosclerosis in humans (p<0.001 vs. no atherosclerosis or control group). Conclusions Profilin-1 expression is significantly enhanced in human atherosclerotic plaques compared to the normal vessel wall, and the serum levels of Profilin-1 correlate with the degree of atherosclerosis in humans. The atherogenic effects exerted by Profilin-1 on VSMCs suggest an auto-/paracrine role within the plaque. These data indicate that Profilin-1 might critically contribute to atherogenesis and may represent a novel therapeutic target.
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Oxysterol and diabetes activate STAT3 and control endothelial expression of Profilin-1 via OSBP1.
The Journal of biological chemistry, 2008Co-Authors: Giulio R. Romeo, Andrius KazlauskasAbstract:Endothelial dysfunction plays a central role in diabetic vascular disease, but its molecular bases are not completely defined. We showed previously that the actin-binding protein proflin-1 was increased in the diabetic endothelium and that attenuated expression of Profilin-1 protected against atherosclerosis. Also 7-ketocholesterol up-regulated Profilin-1 in endothelial cells via transcriptional mechanisms. The present study addressed the pathways responsible for Profilin-1 gene expression in 7-ketocholesterol-stimulated endothelial cells and in the diabetic aorta. In luciferase reporter assays, the response to 7-ketocholesterol within the 5'-flanking region of Profilin-1 was dependent on a single STAT response element. In aortic endothelial cells, 7-ketocholesterol enhanced STAT3 activation, which required JAK2 and tyrosine 394 phosphorylation of oxysterol-binding protein-1. These changes were recapitulated in the aorta of diabetic rats. Also 7-ketocholesterol in cultured endothelial cells and diabetes in the aorta elicited the recruitment of STAT3 and relevant coregulatory factors to the oxysterol-responsive region of the Profilin-1 promoter. These events were required for Profilin-1 up-regulation. These studies identify a previously unrecognized oxysterol-binding protein-mediated mode of activation of STAT3 that controls the expression of the proatherogenic protein Profilin-1 in response to 7-ketocholesterol and the diabetic milieu.
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attenuated expression of Profilin 1 confers protection from atherosclerosis in the ldl receptor null mouse
Circulation Research, 2007Co-Authors: Giulio R. Romeo, Karen S. Moulton, Andrius KazlauskasAbstract:Atherosclerosis-related events are a major cause of morbidity and death worldwide, but the mechanisms underlying atherogenesis are not fully understood. We showed in previous studies that the actin-binding protein Profilin-1 (pfn) was upregulated in atherosclerotic plaques and in endothelial cells (ECs) treated with oxidized low-density lipoproteins (oxLDL). The present study addressed the role of pfn in atheroma formation. To this end, mice with heterozygous deficiency of pfn, Pfn+/−, were crossed with Ldlr−/− mice. After 2 months under a 1.25% cholesterol atherogenic diet, Pfn+/−Ldlr−/− (PfnHet) exhibited a significant reduction in lesion burden compared with Ldlr−/− control mice (PfnWT), whereas total cholesterol and triglyceride levels were similar in the 2 groups. Relevant atheroprotective changes were identified in PfnHet. When compared with PfnWT, aortas from PfnHet mice showed preserved endothelial nitric oxide synthase (eNOS) activation and nitric oxide (NO)-dependent signaling, and reduced vascu...
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Attenuated Expression of Profilin-1 Confers Protection From Atherosclerosis in the LDL Receptor–Null Mouse
Circulation research, 2007Co-Authors: Giulio R. Romeo, Karen S. Moulton, Andrius KazlauskasAbstract:Atherosclerosis-related events are a major cause of morbidity and death worldwide, but the mechanisms underlying atherogenesis are not fully understood. We showed in previous studies that the actin-binding protein Profilin-1 (pfn) was upregulated in atherosclerotic plaques and in endothelial cells (ECs) treated with oxidized low-density lipoproteins (oxLDL). The present study addressed the role of pfn in atheroma formation. To this end, mice with heterozygous deficiency of pfn, Pfn+/−, were crossed with Ldlr−/− mice. After 2 months under a 1.25% cholesterol atherogenic diet, Pfn+/−Ldlr−/− (PfnHet) exhibited a significant reduction in lesion burden compared with Ldlr−/− control mice (PfnWT), whereas total cholesterol and triglyceride levels were similar in the 2 groups. Relevant atheroprotective changes were identified in PfnHet. When compared with PfnWT, aortas from PfnHet mice showed preserved endothelial nitric oxide synthase (eNOS) activation and nitric oxide (NO)-dependent signaling, and reduced vascu...
Zhijie Ding - One of the best experts on this subject based on the ideXlab platform.
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Abstract 4941: Profilin-1 is a key determinant for tumorigenic potential of breast cancer cells
Molecular and Cellular Biology, 2015Co-Authors: Chang Jiang, Zhijie Ding, Marion Joy, Laura L. Vollmer, David Gau, Su Hyeong Kim, Shivendra V. Singh, Andreas Vogt, Partha RoyAbstract:A hallmark of oncogenic transformation is disruption of the actin cytoskeleton, which is partly attributed to altered expression and/or activity of proteins that bind to and regulate the state of polymerization of actin in cells. Profilin-1 (Pfn1) is a key regulator of actin polymerization that is downregulated in human breast cancer, and reduced Pfn1 levels were shown to facilitate dissemination-promoting activities of certain types of breast cancer cells. The objective of the present study was to investigate whether Pfn1 modulation affects tumor initiating capacity of breast cancer cells. Using a MMTV-PyMT transgenic mouse model, we demonstrated that mice engineered for conditional Cre-mediated homozygous deletion of Pfn1 (Pfn1−/−) in the mammary gland develop fewer spontaneous mammary tumors and exhibit longer survival than either wild-type or heterozygous Pfn1-knockout littermates. Haplo-insufficiency of Pfn1 (Pfn1+/−) causes the expected ∼50% downregulation of Pfn1 expression in tumors; however, mammary tumors isolated from Pfn1−/− mice exhibit residual Pfn1 expression that is at least comparable to the level found in tumors derived from Pfn1+/− mice. This scenario is consistent with a competitive disadvantage of Pfn1-null tumor cells for autonomous growth and/or survival, allowing selective outgrowth of tumor cell populations that have incomplete Cre-mediated gene excision of Pfn1, likely resulting from mosaic activation of Cre-driving MMTV-promoter in mammary gland. Acute deletion of floxed-Pfn1 alleles in normal mouse mammary epithelial cells by Cre-adenovirus transduction dramatically impairs their ability to outgrow when seeded sparsely on 3D matrigel. Likewise, human breast cancer cells exhibit retarded outgrowth on 3D matrigel upon stable silencing of Pfn1 expression even though their proliferation on 2D tissue-culture substrate was not affected. Correlated with these phenotypic changes, Pfn1 knockdown suppresses stem-cell-like behavior of breast cancer cells as marked by a significant reduction in both aldehyde dehydrogenase activity and mammosphere forming ability. Collectively, these findings suggest that a minimum level of Pfn1 is essential for tumor initiation of breast cancer cells. Interestingly, the outgrowth-deficient phenotype of Pfn1-depleted breast cancer cells on 3D-matrigel can be fully rescued by addition of collagen-I which suggests that alteration in cell-matrix adhesion and downstream signaling underlies the growth-related phenotypic changes induced by loss of Pfn1. Finally, the outgrowth-deficient phenotype of breast cancer cells can also be elicited in vitro and in vivo by Pfn1 overexpression, further suggesting that an optimum range of Pfn1 expression is conducive for tumor-initiating capacity of breast cancer cells. Based on these results, we conclude that Pfn1 expression level is a major determinant for tumorigenic potential of breast cancer cells. Citation Format: Chang Jiang, Zhijie Ding, Marion Joy, Laura Vollmer, Dave Gau, Su Hyeong Kim, Shivendra Singh, Andreas Vogt, Partha Roy. Profilin-1 is a key determinant for tumorigenic potential of breast cancer cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4941. doi:10.1158/1538-7445.AM2015-4941
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Profilin-1 versus Profilin-2: two faces of the same coin?
Breast cancer research : BCR, 2013Co-Authors: Zhijie Ding, Partha RoyAbstract:Proteins belonging to the Profilin family of actin-binding proteins are considered to be important control elements for actin polymerization and have been linked to a broad spectrum of cellular functions, including cell migration. An intriguing paper recently published in Cancer Cell unveils differential effects of Profilin-1 and Profilin-2, the two major isoforms of Profilin, on actin cytoskeletal regulation, motility, and invasion of breast cancer cells, and further establishes a mechanism underlying Profilin-2's suppressive effect on breast cancer cell migration. This viewpoint discusses the implications of these findings in the context of how Profilins might regulate breast cancer cell motility.
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Molecular insights on context-specific role of Profilin-1 in cell migration
Cell adhesion & migration, 2012Co-Authors: Zhijie Ding, Yongho Bae, Partha RoyAbstract:Profilin-1 (Pfn1) is a ubiquitously expressed actin-monomer binding protein that has been linked to many cellular activities ranging from control of actin polymerization to gene transcription. Traditionally, Pfn1 has been considered to be an essential control element for actin polymerization and cell migration. Seemingly contrasting this view, a few recent studies have shown evidence of an inhibitory action of Pfn1 on motility of certain types of carcinoma cells. In this review, we summarize biochemistry and functional aspects of Pfn1 in normal cells and bring in newly emerged action of Pfn1 in cancer cells that may explain its context-specific role in cell migration.
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Profilin 1 overexpression inhibits proliferation of mda mb 231 breast cancer cells partly through p27kip1 upregulation
Journal of Cellular Physiology, 2010Co-Authors: Li Zou, Zhijie Ding, Partha RoyAbstract:Profilin-1 (Pfn1), a ubiquitously expressed actin-binding protein, has gained interest in epithelial-derived cancer because of its downregulation in expression in various adenocarcinoma. Pfn1 overexpression impairs tumorigenic ability of human breast cancer xenografts thus suggesting that Pfn1 could be a tumor-suppressor protein. The objective of the present study was to determine how Pfn1 overexpression affects cell-cycle progression of breast cancer cells. We show that Pfn1 overexpression in MDA-MB-231 breast cancer cells causes cell-cycle arrest in G1 phase and dramatically reduced proliferation in culture. Pfn1 overexpression results in increased protein stability of p27(kip1) (p27-a major cyclin-dependent kinase inhibitor) and marked elevation in the overall cellular level of p27. Proliferation defect of Pfn1 overexpressers can be partly rescued by silencing p27 expression thus suggesting a critical role of p27 in Pfn1-induced growth inhibition of MDA-MB-231 cells. Finally, Pfn1 overexpression was found to sensitize MDA-MB-231 cells to apoptosis in response to cytotoxic stimulus thus suggesting for the first time that survival of breast cancer cells can also be negatively influenced by Pfn1 upregulation. These findings may provide novel insights underlying Pfn1's tumor-suppressive action.
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Profilin-1 IN CAPILLARY MORPHOGENESIS OF VASCULAR ENDOTHELIAL CELLS
2009Co-Authors: Zhijie DingAbstract:Vascular endothelial cells (VEC) assemble into capillary-like structures during angiogenesis, and this neovascularization process plays an important role in a wide range of physiological and pathological scenarios. Based on significant upregulation of its expression in VEC during capillary morphogenesis, Profilin-1 (Pfn1 - a ubiquitously expressed actin-binding protein) was previously implicated in capillary morphogenesis of VEC. The overall objective of the present study was to investigate whether and how loss of Pfn1 function affects a) the various cellular functions that are important for capillary morphogenesis such as VEC migration, invasion and proliferation, and b) the overall capillary forming ability of VEC. Loss of Pfn1 function in VEC was achieved either by suppressing the overall expression of Pfn1 by RNA interference method or selectively abrogating specific ligand-interactions (actin, proline-rich ligands) of Pfn1 by expressing various point-mutants of Pfn1 in a near-null endogenous Pfn1 background (knockdown and knock-in approach). Loss of Pfn1 expression causes a major change in actin cytoskeleton in VEC. Particularly, there is a significant depletion of actin filaments and focal adhesions in VEC when Pfn1 expression was silenced. Silencing of Pfn1 expression also significantly impairs the migratory ability of VEC. Analyses of leading edge dynamics revealed that Pfn1 depletion results in decreased velocity and frequency of lamellipodial protrusion. Further experiments with point-mutants of Pfn1 showed that both actin and polyproline interactions of Pfn1 are required for efficient lamellipodial protrusion and overall migration of VEC. Loss of Pfn1 expression is associated with reduced dynamics of VE-cadherin dependent cell-cell adhesion, which was also found to be correlated with increased nuclear accumulation of p27 Kip1 (a major cell-cycle inhibitor) and reduced VEC proliferation. Finally, we found that loss of overall expression of Pfn1 significantly impairs collagen gel invasion and three-dimensional (3-D) capillary morphogenesis of VEC. Abolishing either of actin or polyproline interactions of Pfn1 also leads to a dramatic inhibition of capillary mophogenesis of VEC. Taken together, these results demonstrate that Pfn1 plays a critical role in capillary morphogenesis of VEC through its interactions with both actin and polyproline ligands. This study may further imply that Pfn1 could be a novel angiogenesis target.
Tian-lun Yang - One of the best experts on this subject based on the ideXlab platform.
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Downregulation of Profilin-1 Expression Attenuates Cardiomyocytes Hypertrophy and Apoptosis Induced by Advanced Glycation End Products in H9c2 Cells.
BioMed research international, 2017Co-Authors: Dafeng Yang, Tian-lun Yang, Ya Wang, Minna Jiang, Xu Deng, Zhi-fang Pei, Ke Xia, Lingyan Zhu, Mei-fang ChenAbstract:Cardiomyocytes hypertrophy and apoptosis induced by advanced glycation end products (AGEs) is the crucial pathological foundation contributing to the onset and development of diabetic cardiomyopathy (DCM). However, the mechanism remains poorly understood. Here, we report that Profilin-1 (PFN-1), a well-known actin-binding protein, serves as a potent regulator in AGEs-induced cardiomyocytes hypertrophy and apoptosis. PFN-1 was upregulated in AGEs-treated H9c2 cells, which was associated with increased cardiomyocytes hypertrophy and apoptosis. Silencing PFN-1 expression remarkably attenuated AGEs-induced H9c2 cell hypertrophy and apoptosis. Mechanistically, AGEs increased PFN-1 expression through elevating ROS production and RhoA and ROCK2 expression. Consequently, elevated PFN-1 promoted actin cytoskeleton disorganization. When either ROS production/ROCK activation was blocked or cells were treated with Cytochalasin D (actin depolymerizer), H9c2 cells were protected against AGEs-induced cardiac myocyte abnormalities, concomitantly with downregulated expression of PFN-1 and improved actin cytoskeleton alteration. Collectively, these data suggest that PFN-1 may play an important role in AGEs-induced hypertrophy and apoptosis in H9c2 cells.
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Profilin 1 contributes to cardiac injury induced by advanced glycation end products in rats
Molecular Medicine Reports, 2017Co-Authors: Dafeng Yang, Tian-lun Yang, Weiwei Liu, Ya Wang, Minna Jiang, Xu Deng, Fang Huang, Mei-fang ChenAbstract:Cardiac injury, including hypertrophy and fibrosis, induced by advanced glycation end products (AGEs) has an important function in the onset and development of diabetic cardiomyopathy. Profilin-1, a ubiquitously expressed and multifunctional actin-binding protein, has been reported to be an important mediator in cardiac hypertrophy and fibrosis. However, whether Profilin-1 is involved in AGE-induced cardiac hypertrophy and fibrosis remains to be determined. Therefore, the present study aimed to investigate the function of Profilin-1 in cardiac injury induced by AGEs. The model of cardiac injury was established by chronic tail vein injection of AGEs (50 mg/kg/day for 8 weeks) in Sprague-Dawley rats. Rats were randomly assigned to control, AGEs, AGEs + Profilin-1 shRNA adenovirus vectors (AGEs + S)or AGEs + control adenovirus vectors (AGEs + V) groups. Profilin-1 shRNA adenovirus vectors were injected via the tail vein to knockdown Profilin-1 expression at a dose of 3×109 plaque forming units every 4 weeks. Echocardiography was performed to measure cardiac contractile function. Cardiac tissues were stained with Masson's trichrome stain to evaluate ventricular remodeling. The serum levels of procollagen type III N-terminal peptide were detected by ELISA. The expression of Profilin-1, receptor for AGEs (RAGE), Rho, p65, atrial natriuretic peptide, β-myosin heavy chain, matrix metalloproteinase (MMP)-2 and MMP-9 were determined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and/or western blot analysis and immunohistochemistry staining. The results demonstrated that chronic injection of exogenous AGEs led to cardiac dysfunction, hypertrophy and fibrosis, as determined by echocardiography, Masson trichrome staining and the expression of associated genes. The expression of Profilin-1 was markedly increased in heart tissue at the mRNA and protein level following AGE administration, as determined by RT-qPCR and western blotting, which was further confirmed by immunohistochemistry staining. Furthermore, the expression of RAGE, Rho and p65 was also increased at the protein level. Notably, knockdown of Profilin-1 expression ameliorated AGE-induced cardiac injury and reduced the expression of RAGE, Rho and p65. These results indicate an important role for Profilin-1 in AGE-induced cardiac injury, which may provide a novel therapeutic target for patients with diabetic heart failure.
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Profilin‑1 contributes to cardiac injury induced by advanced glycation end‑products in rats.
Molecular medicine reports, 2017Co-Authors: Dafeng Yang, Tian-lun Yang, Weiwei Liu, Ya Wang, Minna Jiang, Xu Deng, Fang Huang, Mei-fang ChenAbstract:Cardiac injury, including hypertrophy and fibrosis, induced by advanced glycation end products (AGEs) has an important function in the onset and development of diabetic cardiomyopathy. Profilin-1, a ubiquitously expressed and multifunctional actin-binding protein, has been reported to be an important mediator in cardiac hypertrophy and fibrosis. However, whether Profilin-1 is involved in AGE-induced cardiac hypertrophy and fibrosis remains to be determined. Therefore, the present study aimed to investigate the function of Profilin-1 in cardiac injury induced by AGEs. The model of cardiac injury was established by chronic tail vein injection of AGEs (50 mg/kg/day for 8 weeks) in Sprague-Dawley rats. Rats were randomly assigned to control, AGEs, AGEs + Profilin-1 shRNA adenovirus vectors (AGEs + S)or AGEs + control adenovirus vectors (AGEs + V) groups. Profilin-1 shRNA adenovirus vectors were injected via the tail vein to knockdown Profilin-1 expression at a dose of 3×109 plaque forming units every 4 weeks. Echocardiography was performed to measure cardiac contractile function. Cardiac tissues were stained with Masson's trichrome stain to evaluate ventricular remodeling. The serum levels of procollagen type III N-terminal peptide were detected by ELISA. The expression of Profilin-1, receptor for AGEs (RAGE), Rho, p65, atrial natriuretic peptide, β-myosin heavy chain, matrix metalloproteinase (MMP)-2 and MMP-9 were determined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and/or western blot analysis and immunohistochemistry staining. The results demonstrated that chronic injection of exogenous AGEs led to cardiac dysfunction, hypertrophy and fibrosis, as determined by echocardiography, Masson trichrome staining and the expression of associated genes. The expression of Profilin-1 was markedly increased in heart tissue at the mRNA and protein level following AGE administration, as determined by RT-qPCR and western blotting, which was further confirmed by immunohistochemistry staining. Furthermore, the expression of RAGE, Rho and p65 was also increased at the protein level. Notably, knockdown of Profilin-1 expression ameliorated AGE-induced cardiac injury and reduced the expression of RAGE, Rho and p65. These results indicate an important role for Profilin-1 in AGE-induced cardiac injury, which may provide a novel therapeutic target for patients with diabetic heart failure.
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The role of Profilin-1 in endothelial cell injury induced by advanced glycation end products (AGEs).
Cardiovascular diabetology, 2013Co-Authors: Qiaoqing Zhong, Tian-lun Yang, Xiu-mei Xie, Mei-fang ChenAbstract:Background Accumulation of advanced glycation end products (AGEs) in the vasculature triggers a series of morphological and functional changes contributing to endothelial hyperpermeability. The reorganisation and redistribution of the cytoskeleton regulated by Profilin-1 mediates endothelial cell contraction, which results in vascular hyperpermeability. This study aimed to investigate the pivotal role of Profilin-1 in the process of endothelial cell damage induced by AGEs.
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Involvement of Profilin-1 in angiotensin II-induced vascular smooth muscle cell proliferation.
Vascular pharmacology, 2011Co-Authors: Jin-fang Cheng, Mei-fang Chen, Yong-jin Wang, Chang-lu Wang, Qiong Yuan, Rui-zheng Shi, Tian-lun YangAbstract:Profilin-1, a regulator of actin polymerization, has recently been linked to vascular hypertrophy and remodeling. Whether Profilin-1 is involved in angiotensin (Ang) II-induced proliferation of vascular smooth muscle cells leading to vascular remodeling in hypertension remains unclear. The present study was designed to analyze the correlation of Profilin-1 and vascular remodeling during hypertension and to evaluate the role of Profilin-1 in proliferation of vascular smooth muscle cells and the underlying mechanisms. The vascular morphology and the expression of Profilin-1 in arterial tissues of spontaneously hypertensive rats and Wistar-Kyoto rats were assessed. The Profilin-1 expression was significantly increased concomitantly with definite vascular remodeling by evaluating the media thickness, lumen diameter, media thickness-to-lumen diameter ratio and mean nuclear area in artery media in spontaneously hypertensive rats, which was inhibited by treatment with losartan. In cultured rat aortic smooth muscle cells (RASMCs), Ang II induced Profilin-1 expression in a dose- and time-dependent manner. Knockdown of Profilin-1 using small hairpin RNA inhibited Ang II-induced proliferation of RASMCs. Moreover, blockade of JAK2/STAT3 signaling pathway also inhibited Ang II-induced proliferation of RASMCs and Profilin-1 expression. These results suggest that Profilin-1 mediates the proliferation of RASMCs induced by Ang II via activation of Ang II type 1 receptor/JAK2/STAT3 signaling pathway, which may contribute to vascular remodeling in hypertension.
Giulio R. Romeo - One of the best experts on this subject based on the ideXlab platform.
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The multifaceted role of Profilin-1 in adipose tissue inflammation and glucose homeostasis
Adipocyte, 2013Co-Authors: Munkyong Pae, Giulio R. RomeoAbstract:Profilin-1 (pfn) is a small ubiquitous protein that can bind to: (1) G-actin, (2) phosphatidylinositol 4,5-bisphosphate, and (3) a heterogeneous group of proteins harboring poly-l-proline stretches. Through these interactions, pfn integrates signaling from a diverse array of extracellular cues with actin cytoskeleton dynamics. Cumulating evidence indicates that changes in pfn levels are associated and may play a pathogenic role in such inflammatory diseases as atherosclerosis and glomerulonephritis. We recently demonstrated that high fat diet (HFD) increases pfn expression in the white adipose tissue (WAT), but not in the liver or the muscle. Pfn heterozygote mice (PfnHet) were protected against HFD-induced glucose intolerance, and WAT and systemic inflammation, when compared to pfn wild-type mice. In addition to blunted accumulation of macrophages and reduced "pro-inflammatory" cytokines, the WAT of PfnHet exhibited preserved frequency of regulatory T cells. These findings suggest that pfn levels in WAT-both adipocytes and hematopoietic-derived cells-can modulate immune homeostasis within the WAT and glucose tolerance systemically. Here, we review the interaction of pfn with his diverse array of binding partners and discuss mechanisms that may underlie the effects of pfn dosage on insulin sensitivity and metabolic inflammation.
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Profilin-1 Haploinsufficiency Protects Against Obesity-Associated Glucose Intolerance and Preserves Adipose Tissue Immune Homeostasis
Diabetes, 2013Co-Authors: Giulio R. Romeo, Munkyong Pae, Delphine Eberlé, Jongsoon Lee, Steven E. ShoelsonAbstract:Metabolic inflammation may contribute to the pathogenesis of obesity and its comorbidities, including type 2 diabetes and cardiovascular disease. Previously, we showed that the actin-binding protein Profilin-1 (pfn) plays a role in atherogenesis because pfn heterozygote mice (PfnHet) exhibited a significant reduction in atherosclerotic lesion burden and vascular inflammation. In the current study, we tested whether pfn haploinsufficiency would also limit diet-induced adipose tissue inflammation and insulin resistance (IR). First, we found that a high-fat diet (HFD) upregulated pfn expression in epididymal and subcutaneous white adipose tissue (WAT) but not in the liver or muscle of C57BL/6 mice compared with normal chow. Pfn expression in WAT correlated with F4/80, an established marker for mature macrophages. Of note, HFD elevated pfn protein levels in both stromal vascular cells and adipocytes of WAT. We also found that PfnHet were significantly protected from HFD-induced glucose intolerance observed in pfn wild-type mice. With HFD, PfnHet displayed blunted expression of systemic and WAT proinflammatory cytokines and decreased accumulation of adipose tissue macrophages, which were also preferentially biased toward an M2-like phenotype; this correlated with preserved frequency of regulatory T cells. Taken together, the findings indicate that pfn haploinsufficiency protects against diet-induced IR and inflammation by modulating WAT immune homeostasis.
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Profilin 1 is expressed in human atherosclerotic plaques and induces atherogenic effects on vascular smooth muscle cells
PLOS ONE, 2010Co-Authors: Evren Caglayan, Giulio R. Romeo, Kai Kappert, Margarete Odenthal, Michael Sudkamp, Simon C Body, Stanton K Shernan, Daniel Hackbusch, Marius Vantler, Andrius KazlauskasAbstract:Background Profilin-1 is an ubiquitous actin binding protein. Under pathological conditions such as diabetes, Profilin-1 levels are increased in the vascular endothelium. We recently demonstrated that Profilin-1 overexpression triggers indicators of endothelial dysfunction downstream of LDL signaling, and that attenuated expression of Profilin-1 confers protection from atherosclerosis in vivo. Methodology Here we monitored Profilin-1 expression in human atherosclerotic plaques by immunofluorescent staining. The effects of recombinant Profilin-1 on atherogenic signaling pathways and cellular responses such as DNA synthesis (BrdU-incorporation) and chemotaxis (modified Boyden-chamber) were evaluated in cultured rat aortic and human coronary vascular smooth muscle cells (VSMCs). Furthermore, the correlation between Profilin-1 serum levels and the degree of atherosclerosis was assessed in humans. Principal Findings In coronary arteries from patients with coronary heart disease, we found markedly enhanced Profilin expression in atherosclerotic plaques compared to the normal vessel wall. Stimulation of rat aortic and human coronary VSMCs with recombinant Profilin-1 (10−6 M) in vitro led to activation of intracellular signaling cascades such as phosphorylation of Erk1/2, p70S6 kinase and PI3K/Akt within 10 minutes. Furthermore, Profilin-1 concentration-dependently induced DNA-synthesis and migration of both rat and human VSMCs, respectively. Inhibition of PI3K (Wortmannin, LY294002) or Src-family kinases (SU6656, PP2), but not PLCγ (U73122), completely abolished Profilin-induced cell cycle progression, whereas PI3K inhibition partially reduced the chemotactic response. Finally, we found that Profilin-1 serum levels were significantly elevated in patients with severe atherosclerosis in humans (p<0.001 vs. no atherosclerosis or control group). Conclusions Profilin-1 expression is significantly enhanced in human atherosclerotic plaques compared to the normal vessel wall, and the serum levels of Profilin-1 correlate with the degree of atherosclerosis in humans. The atherogenic effects exerted by Profilin-1 on VSMCs suggest an auto-/paracrine role within the plaque. These data indicate that Profilin-1 might critically contribute to atherogenesis and may represent a novel therapeutic target.
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Profilin-1 Is Expressed in Human Atherosclerotic Plaques and Induces Atherogenic Effects on Vascular Smooth Muscle Cells
PloS one, 2010Co-Authors: Evren Caglayan, Giulio R. Romeo, Kai Kappert, Margarete Odenthal, Michael Sudkamp, Simon C Body, Stanton K Shernan, Daniel Hackbusch, Marius Vantler, Andrius KazlauskasAbstract:Background Profilin-1 is an ubiquitous actin binding protein. Under pathological conditions such as diabetes, Profilin-1 levels are increased in the vascular endothelium. We recently demonstrated that Profilin-1 overexpression triggers indicators of endothelial dysfunction downstream of LDL signaling, and that attenuated expression of Profilin-1 confers protection from atherosclerosis in vivo. Methodology Here we monitored Profilin-1 expression in human atherosclerotic plaques by immunofluorescent staining. The effects of recombinant Profilin-1 on atherogenic signaling pathways and cellular responses such as DNA synthesis (BrdU-incorporation) and chemotaxis (modified Boyden-chamber) were evaluated in cultured rat aortic and human coronary vascular smooth muscle cells (VSMCs). Furthermore, the correlation between Profilin-1 serum levels and the degree of atherosclerosis was assessed in humans. Principal Findings In coronary arteries from patients with coronary heart disease, we found markedly enhanced Profilin expression in atherosclerotic plaques compared to the normal vessel wall. Stimulation of rat aortic and human coronary VSMCs with recombinant Profilin-1 (10−6 M) in vitro led to activation of intracellular signaling cascades such as phosphorylation of Erk1/2, p70S6 kinase and PI3K/Akt within 10 minutes. Furthermore, Profilin-1 concentration-dependently induced DNA-synthesis and migration of both rat and human VSMCs, respectively. Inhibition of PI3K (Wortmannin, LY294002) or Src-family kinases (SU6656, PP2), but not PLCγ (U73122), completely abolished Profilin-induced cell cycle progression, whereas PI3K inhibition partially reduced the chemotactic response. Finally, we found that Profilin-1 serum levels were significantly elevated in patients with severe atherosclerosis in humans (p
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Oxysterol and diabetes activate STAT3 and control endothelial expression of Profilin-1 via OSBP1.
The Journal of biological chemistry, 2008Co-Authors: Giulio R. Romeo, Andrius KazlauskasAbstract:Endothelial dysfunction plays a central role in diabetic vascular disease, but its molecular bases are not completely defined. We showed previously that the actin-binding protein proflin-1 was increased in the diabetic endothelium and that attenuated expression of Profilin-1 protected against atherosclerosis. Also 7-ketocholesterol up-regulated Profilin-1 in endothelial cells via transcriptional mechanisms. The present study addressed the pathways responsible for Profilin-1 gene expression in 7-ketocholesterol-stimulated endothelial cells and in the diabetic aorta. In luciferase reporter assays, the response to 7-ketocholesterol within the 5'-flanking region of Profilin-1 was dependent on a single STAT response element. In aortic endothelial cells, 7-ketocholesterol enhanced STAT3 activation, which required JAK2 and tyrosine 394 phosphorylation of oxysterol-binding protein-1. These changes were recapitulated in the aorta of diabetic rats. Also 7-ketocholesterol in cultured endothelial cells and diabetes in the aorta elicited the recruitment of STAT3 and relevant coregulatory factors to the oxysterol-responsive region of the Profilin-1 promoter. These events were required for Profilin-1 up-regulation. These studies identify a previously unrecognized oxysterol-binding protein-mediated mode of activation of STAT3 that controls the expression of the proatherogenic protein Profilin-1 in response to 7-ketocholesterol and the diabetic milieu.
