Hypertrophic scar (HTS) formation is characterized by exuberant fibroproliferation for reasons that remain poorly understood1. One important but often overlooked component of wound repair is mechanical force, which regulates reciprocal cell-matrix interactions through focal adhesion components including focal adhesion kinase (FAK)1,2. Here we report that FAK is activated following cutaneous injury and that this activation is potentiated by mechanical loading. Transgenic mice lacking fibroblast-specific FAK exhibit significantly less fibrosis in a preclinical model of HTS formation. Inflammatory pathways involving monocyte chemoattractant protein-1 (MCP-1), a chemokine highly implicated in human skin fibrosis3, are triggered following FAK activation, mechanistically linking physical force to fibrosis. Further, small molecule inhibition of FAK effectively abrogates fibroproliferative mechanisms in human cells and significantly reduces scar formation in vivo. Collectively, these findings establish a molecular basis for HTS formation based on the mechanical activation of fibroblast-specific FAK and demonstrate the therapeutic potential of targeted mechanomodulatory strategies.
Focal adhesion kinase links mechanical force to skin fibrosis via inflammatory signaling.
Sex, Specimen part
View SamplesLung cancer remains the leading cause of cancer death. Genome sequencing of lung tumors from patients with Squamous Cell Carcinoma has identified SMAD4 to be frequently mutated. Here we used a novel mouse model to determine the molecular mechanisms regulated by loss of Smad4 which lead to lung cancer progression. Mice with ablation of Pten and Smad4 in airway epithelium developed metastatic adenosquamous tumors. Comparative transcriptomic and in vivo cistromic analyses determined that loss of PTEN and SMAD4 resulted in activation of the ELF3 and the ErbB2 pathway due to decreased ERRFI1s expression, a negative regulator of ERBB2 in mice and human cells. The combinatorial inhibition of ErbB2 and Akt signaling attenuated tumor progression and cell invasion, respectively. Expression profiles analysis of human lung tumors substantiated the importance of the ErbB2/Akt/ELF3 signaling pathway as both prognostic biomarkers and therapeutic drug targets for treating lung cancer.
ErbB2 Pathway Activation upon Smad4 Loss Promotes Lung Tumor Growth and Metastasis.
Age, Specimen part
View SamplesLung cancer is the leading cause of cancer related death in both men and women in the United States. Recently, Smad4 was discovered to be common somatic alteration in human squamous cell lung cancer. Our goal was to delineate the role of Smad4 in lung cancer. We have shown for the first time that the ablation of Pten and Smad4 in the murine airway epithelium harbors a metastatic proximal adeno-squamous lung cancer.
ErbB2 Pathway Activation upon Smad4 Loss Promotes Lung Tumor Growth and Metastasis.
Specimen part, Disease, Disease stage
View SamplesImbalances in glucose and energy homeostasis are at the core of the worldwide epidemic of obesity and diabetes. Here, we illustrate an important role of the TGF-beta/Smad3 signaling pathway in regulating glucose and energy homeostasis. Smad3 deficient mice are protected from diet-induced obesity and diabetes. Interestingly, the metabolic protection is accompanied by Smad3-/- white adipose tissue acquiring the bioenergetic and gene expression profile of brown fat/skeletal muscle. Smad3-/- adipocytes demonstrate a marked increase in mitochondrial biogenesis, with a corresponding increase in basal respiration, and Smad3 acts as a repressor of PGC-alpha1 expression. We observe significant correlation between TGF-beta1 levels and adiposity in rodents and humans. Further, systemic blockade of TGF-beta1 signaling protects mice from obesity, diabetes and hepatic steatosis. Together, these results demonstrate that TGF-beta signaling regulates glucose tolerance and energy homeostasis and suggest that modulation of TGF-beta1 activity might be an effective treatment strategy for obesity and diabetes.
Protection from obesity and diabetes by blockade of TGF-β/Smad3 signaling.
Treatment
View SamplesIdentification of genes differentially regulated after treatment of zebrafish embryos from 50% epiboly to 24hpf with 6.5uM leflunomide A six chip study comparing expression levels of zebrafish embryos treated with leflunomide 6.5uM
DHODH modulates transcriptional elongation in the neural crest and melanoma.
Specimen part, Treatment, Subject
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