Project description:Mechanical forces generated through adhesive interaction of endothelial cells (EC) influence nuclear envelope and thereby gene transcription. Alteration in EC mechanical forces may trigger aberrant gene transcription leading to lethal vascular diseases including acute lung injury (ALI). The intrinsic pathways that instruct EC nuclear-mechanotransduction and thereby maintains vascular homeostasis remain elusive. We have identified focal adhesion kinase (FAK)-mediated mechanotransduction at the nuclear envelope in instructing transcription of EC-barrier protective genes. We show that loss of EC-FAK increases intracellular tension, which in turn activates nuclear envelop protein emerin, and DNA methyltransferase 3a (DNMT3a). Methylation of transcription factor KLF2 promoter by DNMT3a impaired KLF2 synthesis and transcription of the crucial barrier-maintaining gene, S1PR1. Restoring KLF2 or S1PR1 expression or impairing emerin or DNMT3a activity rescued vascular homeostasis in lungs with FAK-deficient or WT-damaged endothelium. Thus, FAK protects against tension-induced aberrant DNA methylation in EC and is a promising target to prevent ALI.
Project description:We report that loss of CCM3/PDCD10 in fibroblasts induces FAK/Src-paxillin signalling driving actomyosin-dependent mechanotransduction leading to YAP/TAZ signalling. In vivo, loss of CCM3 in fibroblasts drives excessive tissue remodelling leading to the dissemination of breast cancer cells to distant organs.
Project description:Endothelial cell (EC) attachment to the matrix and adjacent cells generates a mechanical environment that maintains a restrictive barrier against the uncontrolled influx of circulating protein and immune cells. Mechanisms that mediate the transition from restrictive to leaky endothelium, a hallmark of tissue injury exemplified by acute lung injury (ALI), remain elusive. Here, we show that FAK sensing and transmission of mechanical tension to the EC nucleus governs cell fate. In FAK-deleted EC, increased EC tension activated DNMT3a, which induced methylation of the KLF2 promoter leading to impaired synthesis of KLF2 and restrictive EC transcriptome, including S1PR1. FAK suppressed DNMT3a activity by restricting the tyrosine phosphorylation of nuclear envelope protein, emerin at Y74/Y95, and its localization in a nuclear cap. Inhibiting emerin phosphorylation or DNMT3a activity in damaged lungs enabled KLF2 transcription of S1PR1, rescuing the restrictive EC phenotype. Our works reveal a paradigm whereby FAK sensing of tension transmission to the nucleus maintains restrictive EC transcriptome and lung homeostasis.
Project description:Chronic allodynia stemming from peripheral stump neuromas can persist for extended periods, significantly compromising patients’ quality of life. Conventional managements for nerve stumps have demonstrated limited effectiveness in ensuring their orderly termination. In this study, we present a spatially confined conduit strategy, designed to enhance the self-organization of regenerating nerves after truncation. This innovative approach elegantly enables the autonomous slowing of axonal outgrowth in response to the gradually constricting space, concurrently suppressing neuroinflammation through YAP-mediated mechanotransduction activation. Meanwhile, the decelerating axons exhibit excellent alignment and remyelination, thereby helping to prevent failure modes in nerve self-organization, such as axonal twisting in congested regions and overgrowth beyond the conduit's capacity.
Project description:Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that plays an important role in proliferation, motility, adhesion, invasion, angiogenesis, and survival signaling. Focal adhesion kinase has been shown to be overexpressed in many types of tumors, including breast cancer at early stages of tumorigenesis. To study the biological role of FAK in breast tumorigenesis, we used FAKsiRNA to down-regulate FAK in MCF-7 cell lines.
Project description:Gene copy number changes, cancer stem cell (CSC) increases, and platinum chemotherapy resistance contribute to poor prognosis in patients with recurrent high grade serous ovarian cancer (HGSOC). CSC phenotypes involving Wnt-b-catenin and aldehyde dehydrogenase activities, platinum resistance, and tumor initiating frequency are here associated with spontaneous genetic gains, including genes encoding KRAS, MYC and FAK, in a new murine model of ovarian cancer (KMF). Noncanonical FAK signaling was sufficient to sustain human and KMF tumorsphere proliferation, CSC survival, and platinum resistance. Increased FAK tyrosine phosphorylation occurred in HGSOC patient tumors surviving neo-adjuvant platinum and paclitaxel chemotherapy and platinum resistant tumorspheres acquired FAK dependence for growth. Importantly, combining a pharmacologic FAK inhibitor with platinum overcame chemoresistance and triggered apoptosis in vitro and in vivo. Knockout, rescue, genomic and transcriptomic analyses collectively identified more than 400 genes regulated along a FAK/b-catenin/Myc axis impacting stemness and DNA repair in HGSOC, with 66 genes gained in a majority of Cancer Genome Atlas samples. Together, these results support combinatorial testing of FAK inhibitors for the treatment of recurrent ovarian cancer.
Project description:Purpose: The goals of this study are to compare the effect of FFSS, FAK inhibitor, and FAK gene deletion on gene expression of NGS-derived RNA-sequencing.
Project description:Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that plays an important role in proliferation, motility, adhesion, invasion, angiogenesis, and survival signaling. Focal adhesion kinase has been shown to be overexpressed in many types of tumors, including breast cancer at early stages of tumorigenesis. To study the biological role of FAK in breast tumorigenesis, we used FAKsiRNA to down-regulate FAK in MCF-7 cell lines. Experiment Overall Design: Eight samples were analyzed in MCF-7, MCF-7-Vector, MCF-7 control (luciferase) siRNA and FAKsiRNA#1, FAKsiRNA#2