Project description:Available evidence has suggested that integrin-linked kinase (ILK) underwent over-expression in ovarian cancer while specific gene silencing of ILK resulted in apoptosis of ovarian cancer cells. Here, potential mechanisms in which ILK induces cell apoptosis was explored from the perspective of microRNA (miRNA) expression.
Project description:Available evidence has suggested that integrin-linked kinase (ILK) underwent over-expression in ovarian cancer while specific gene silencing of ILK resulted in apoptosis of ovarian cancer cells. Here, potential mechanisms in which ILK induces cell apoptosis was explored from the perspective of microRNA (miRNA) expression. Alteration in global miRNA expression profile was detected by miRNA microarray technique after ILK shRNA expression lentivirus was transfected into A2780 cells (n = 3). Additionally, the A2780 cells infected by scrambled shRNA lentivirus were treated as negtive control (n = 3).
Project description:ILK is essential for proper development of hair follicles, and for epidermal integrity and repair after injury. To better understand the pathways modulated by ILK in the epidermis, we compared the transcriptomes of ILK-deficient and -expressing epidermis using microarray analyses. Ilktm1Star (with floxed Ilk alleles) and Tg(KRT14-cre)1Amc/J mice were bred, and the resulting mice were bred again with Ilktm1Star mice, to generate animals heterozygos for the KRT14-cre transgene and either heterozygous (ILK-expressing) or homozygous (ILK-deficient) for the floxed Ilk alleles. The epidermis of 3 day-old animals was harvested and used to prepare RNA for the microarrays. The animals used were littermates. RNA from the epidermis of five ILK-deficient and five ILK-expressing mice were used.
Project description:Invasion of leukocytes, including neutrophils, in response to injury or infection relies on the orchestrated activation of integrins. The neutrophil integrin lymphocyte function-associated antigen-1 (LFA-1) has been implicated in the regulation of leukocyte adhesion by binding to ICAM-1 expressed on activated endothelial cells. The activation-dependent conformational change of LFA-1 to the high affinity conformation (H+) requires kindlin-3 binding to the tail of the β2-integrin. How the integrin linked kinase (ILK) affects activation of β2-integrins in leukocytes is currently unknown. Here, utilizing in vitro microfluidic adhesion chambers with conformation specific antibodies for neutrophil-like HL-60 cells, we show that knockdown of ILK reduces the conformational change of β2-integrins to the H+ conformation. Consequently, ILK-deficient mice show defects of leukocyte adhesion and recruitment in a chemokine and integrin-dependent cremaster muscle model and in a clinically relevant model of renal-ischemia-reperfusion-injury. Absence of protein kinase C (PKC)-α, which is known to phosphorylate Kindlin-3, reproduces such phenotype in bone marrow chimeric mice. ILK is required for chemokine-induced upregulation of PKC-α activity. Mass spectrometry analysis and western blot analyses revealed a stimulation- and ILK-dependent phosphorylation of kindlin-3 upon activation. Our data thus show that ILK impacts kindlin-3-dependent conformational activation of LFA-1, thus contributing to an inflammatory response.
Project description:Neural crest defects lead to congenital heart disease involving outflow tract (OFT) malformation. Integrin-linked-Kinase (ILK) plays important roles in multiple cellular processes and embryogenesis. ILK is expressed in neural crest cells (NCC), but its role in NCC and OFT morphogenesis remains unknown. We used microarrays to detail the global programme of gene expression underlying the morphogenesis of the cardiac neural crest and outflow tract. The outflow tract of control and ILK mutant mouse embryos at E10.5 were dissected and dissociated. Neural crest cells were FACS sorted and used for RNA extraction and hybridization on Affymetrix microarrays.
Project description:Neural crest defects lead to congenital heart disease involving outflow tract (OFT) malformation. Integrin-linked-Kinase (ILK) plays important roles in multiple cellular processes and embryogenesis. ILK is expressed in neural crest cells (NCC), but its role in NCC and OFT morphogenesis remains unknown. We used microarrays to detail the global programme of gene expression underlying the morphogenesis of the cardiac neural crest and outflow tract.
Project description:ILK is essential for proper development of hair follicles, and for epidermal integrity and repair after injury. To better understand the pathways modulated by ILK in the epidermis, we compared the transcriptomes of ILK-deficient and -expressing epidermis using microarray analyses.
Project description:Insulin-like growth factor-binding protein 2 (IGFBP2) is increasingly recognized as a glioma oncogene, emerging as a target for therapeutic intervention. In this study, we used an integrative approach to characterizing the IGFBP2 network, combining transcriptional profiling of human glioma with validation in glial cells and the replication competent ASLV long terminal repeat with a splice acceptor/tv-a glioma mouse system. We demonstrated that IGFBP2 expression is closely linked to genes in the integrin and integrin-linked kinase (ILK) pathways and that these genes are associated with prognosis. We further showed that IGFBP2 activates integrin ?1 and down- stream invasion pathways, requires ILK to induce cell motility, and activates NF-?B. Most significantly, the IGFBP2/integrin/ILK/NF-?B network functions as a physiologically active signaling pathway in vivo by driving glioma progression; interfering with any point in the pathway markedly inhibits progression. The results of this study reveal a signaling pathway that is both targetable and highly relevant to improving the survival of glioma patients. We performed cDNA microarray analysis to compare two stably expressing cell lines originating from SNB19; two clones expressing a mutant form of IGFBP2 that cannot bind integrin (RGD ? RGE point mutation; referred to as RGE mutant); and two clones expressing wild-type IGFBP2. SNB19 clones transfected with empty vector were placed in the reference channel in each hybridization.
Project description:Insulin-like growth factor-binding protein 2 (IGFBP2) is increasingly recognized as a glioma oncogene, emerging as a target for therapeutic intervention. In this study, we used an integrative approach to characterizing the IGFBP2 network, combining transcriptional profiling of human glioma with validation in glial cells and the replication competent ASLV long terminal repeat with a splice acceptor/tv-a glioma mouse system. We demonstrated that IGFBP2 expression is closely linked to genes in the integrin and integrin-linked kinase (ILK) pathways and that these genes are associated with prognosis. We further showed that IGFBP2 activates integrin β1 and down- stream invasion pathways, requires ILK to induce cell motility, and activates NF-κB. Most significantly, the IGFBP2/integrin/ILK/NF-κB network functions as a physiologically active signaling pathway in vivo by driving glioma progression; interfering with any point in the pathway markedly inhibits progression. The results of this study reveal a signaling pathway that is both targetable and highly relevant to improving the survival of glioma patients.
Project description:Glioblastomas (GBM) are driven by malignant neural stem-like cells that display extensive heterogeneity and phenotypic plasticity, which drives tumour progression and therapeutic resistance. Here we show that the nodal extracellular matrix-cell adhesion protein integrin-linked kinase (ILK) is a key determinant of phenotypic plasticity and the mesenchymal-like, invasive cell state in mouse GBM stem cells. We found that an ILK-STAT3 signalling pathway is required for plasticity that enables the transition of GBM stem cells to an astrocyte-like state both in vitro andin vivo. GBM cells genetically depleted of ILK become predominantly stabilised in a transcriptionally-defined progenitor-like state that is characterised by lack of response to differentiation cues and constitutive proliferation. Loss of ILK or interference with STAT3 impairs differentiation potential, reducing phenotypic plasticity of tumour cell populations; additionally, ILK loss causes a mesenchymal- to epithelial-like morphological transition and suppression of malignancy-associated features. Our work defines ILK as a central regulator of multiple GBM phenotypes including phenotypic plasticity and mesenchymal state.