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Background and Purpose: Atherosclerotic vascular disease is the leading cause of mortality and morbidity worldwide. Our previous study uncovered that endothelium‐specific knockdown of YAP suppresses atherogenesis, suggesting that YAP is a promising therapeutic target against atherosclerotic vascular disease. We established a drug screening platform, which aimed to identify new YAP inhibitors for anti‐atherosclerotic treatment. Experimental Approach: Drug screening was performed by a luciferase reporter gene assay. RNA sequencing was performed to acquire the transcriptomic profile of CBL0137‐treated endothelial cells. We assessed and validated the inhibitory effect of CBL0137 on YAP activity and inflammatory response in HUVECs and HAECs. We evaluated the vasoprotective effect of CBL0137 in vivo against plaque formation in ApoE−/− mice, using both disturbed flow‐induced and chronic western diet‐induced atherosclerotic models. Key Results: We identified CBL0137 as a novel YAP inhibitor from an FDA drug library. CBL0137 inhibited YAP activity by restraining its phosphorylation at Y357. CBL0137 inhibited YAP activity to repress endothelial inflammation. Mechanistically, CBL0137 suppressed YAP phosphorylation at Y357 via the tyrosine‐protein kinase Src. Furthermore, administration of CBL0137 ameliorated endothelial inflammation and the atherogenesis induced by disturbed flow and consumption of an atherogenic diet in ApoE−/− mice. Conclusion and Implications: To our knowledge, this is the first study to identify CBL0137 as a novel YAP inhibitor. We have demonstrated that pharmacologically targeting YAP by CBL0137 inhibits atherogenesis. The present results suggest that CBL0137 holds promise as a new drug for the treatment of atherosclerotic vascular disease. [ABSTRACT FROM AUTHOR]

Transfection processes and cDNA clones from an ovarian carcinoma cell line help detect a human oncogene TC21 that belongs to the RAS gene superfamily. Single point mutation and replacement of leucine with glutamine stimulates transforming activities in the oncogene. Unlike the cDNA clone, the ovarian tumor genomic DNA expressing TC21 allele mutations do not stimulate transforming activities.

Background and Purpose Experimental Approach Key Results Conclusion and Implications Previous studies have shown that Src can regulate inflammation and tumour progression. However, the mechanisms by which Src regulates the inflammatory response of vascular endothelium and atherogenesis are currently poorly understood. This study aimed to investigate the role of Src in endothelial inflammation and atherogenesis, as well as the underlying mechanisms.Real‐time quantitative PCR was used to measure the mRNA levels of inflammatory genes. The phosphorylation and localization of proteins were examined using western blotting and immunofluorescence, respectively. The level of p‐Src Y416 in mouse endothelium was directly determined using en face staining. Endothelial‐specific knockdown of Src was achieved by tail vein injection of AAV‐sgSrc in ApoE−/−; Cas9LSL/LSL; Cdh5‐cre mice. Atherosclerosis was induced by partial ligation of the carotid artery.Oscillatory shear stress (OSS) promotes the phosphorylation of Src at Y416 in endothelial cells, and Piezo1 is required for this regulatory process. Overexpression of constitutively active Src promotes endothelial inflammation, as well as phosphorylation of Stat3 (at Y705) and its nuclear translocation. Endothelial inflammation induced by OSS was abolished by the Src inhibitor dasatinib or si‐Src. Dasatinib, when administered orally, reduced endothelial inflammation and plaque formation in ApoE−/− mice induced by partial carotid artery ligation. Additionally, plaque formation was decreased in the ligated left carotid artery of mice with endothelial‐specific Src knockdown.Disturbed flow promotes endothelial inflammation and atherogenesis through the Piezo1‐Src‐Stat3 pathway. Therefore, inhibiting Src in endothelial cells could be a promising therapeutic strategy to treat atherogenesis. [ABSTRACT FROM AUTHOR]

A cDNA from human keratinocyte growth factor receptor (KGFR) was isolated and cloned in a study of mitogenic signalling of growth control genes. KGFR was found to be a highly specific receptor for KGF and acidic fibroblast growth factor (FGF). FGF receptor 2 (FGFR2) showed affinity for basic and acidic FGF only. Two alternative exons for the region of divergence were identified in the bek gene. Results indicated that two growth factor receptors exhibiting varied ligand-binding specificities and expression patterns were encoded by two alternative transcripts of a single gene.

HGF WAS INITIALLY DETECTED AS A hormone-like activity capable of stimulating hepatocyte proliferation [1]. This growth factor is expressed by stromal fibroblasts and is mitogenic for a variety of cell [...]

Abstract Background Cowden Syndrome (CS) patients with germ line point mutations in the PTEN gene are at high risk for developing breast cancer. It is believed that cells harboring these mutant PTEN alleles are predisposed to malignant conversion. This article will characterize the biochemical and biological properties of a mutant PTEN protein found in a commonly used metastatic breast cancer cell line. Methods The expression of PTEN in human breast carcinoma cell lines was evaluated by Western blotting analysis. Cell line MDA-MB-453 was selected for further analysis. Mutation analysis of the PTEN gene was carried out using DNA isolated from MDA-MB-453. Site-directed mutagenesis was used to generate a PTEN E307K mutant cDNA and ectopic expressed in PC3, U87MG, MCF7 and Pten-/- mouse embryo fibroblasts (MEFS). Histidine (His)-tagged PTEN fusion protein was generated in Sf9 baculovirus expression system. Lipid phosphatase and ubiquitination assays were carried out to characterize the biochemical properties of PTEN E307K mutant. The intracellular localization of PTEN E307K was determined by subcellular fractionation experiments. The ability of PTEN E307K to alter cell growth, migration and apoptosis was analyzed in multiple PTEN-null cell lines. Results We found a mutation in the PTEN gene at codon 307 in MDA-MB-453 cell line. The glutamate (E) to lysine (K) substitution rendered the mutant protein to migrate with a faster mobility on SDS-PAGE gels. Biochemically, the PTEN E307K mutant displayed similar lipid phosphatase and growth suppressing activities when compared to wild-type (WT) protein. However, the PTEN E307K mutant was present at higher levels in the membrane fraction and suppressed Akt activation to a greater extent than the WT protein. Additionally, the PTEN E307K mutant was polyubiquitinated to a greater extent by NEDD4-1 and displayed reduced nuclear localization. Finally, the PTEN E307K mutant failed to confer chemosensitivity to cisplatinum when re-expressed in Pten-/- MEFS. Conclusions Mutation at codon 307 in PTEN C2 loop alters its subcellular distribution with greater membrane localization while being excluded from the cell nucleus. This mutation may predispose breast epithelial cells to malignant transformation. Also, tumor cells harboring this mutation may be less susceptible to the cytotoxic effects of chemotherapeutics.

HEPATOCYTE GROWTH FACTOR (HGF) was first purified from human and rabbit plasma and rat platelets on the basis of its ability to stimulate mitogenesis of rat hepatocytes (1-3). Thus, HGF [...]