Discovery of a small molecule that selectively destabilizes Cryptochrome 1 and enhances life span in p53 knockout mice

Cryptochromes are negative transcriptional regulators of the circadian clock in mammals. It is not clear how reducing the level of endogenous level of the CRY1 in mammals will affect circadian rhythm and the relation of such a decrease with apoptosis is unknown. Here, we discovered a molecule that destabilizes Cryptochrome 1 (CRY1) both in vitro and in vivo. The small molecule, called M47, selectively enhanced the degradation rate of CRY1 by increasing its ubiquitination and the period of U2OS Bmal1-dLuc cells. In addition, subcellular fractionation studies from mice liver indicated that M47 enhanced degradation rate of the CRY1 level in the nucleus. Furthermore, M47-mediated CRY1 reduction enhanced cisplatin-induced apoptosis in Ras-transformed p53 null fibroblast cells. Finally, systemic repetitive administration of M47 increased the median lifespan of p53-/- mice by ~25%. Collectively our data suggest that M47 is a very promising molecule to treat forms of cancer depending on the p53 mutation.

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Rapid TNFR1-dependent lymphocyte depletion in vivo with a selective chemical inhibitor of IKKβ

Blood ◽

10.1182/blood-2005-09-3852 ◽

2006 ◽

Vol 107 (11) ◽

pp. 4266-4273 ◽

Cited By ~ 51

Author(s):

Kumiko Nagashima ◽

Vito G. Sasseville ◽

Danyi Wen ◽

Andrew Bielecki ◽

Hua Yang ◽

...

Keyword(s):

Bone Marrow ◽

B Cells ◽

Small Molecule ◽

Mouse Bone Marrow ◽

Tnf Receptor ◽

Molecule Inhibitor ◽

Induced Apoptosis ◽

Potential Use

AbstractThe transcription factor NF-κB plays a central role in regulating inflammation and apoptosis, making it a compelling target for drug development. We identified a small molecule inhibitor (ML120B) that specifically inhibits IKKβ, an Ikappa-B kinase that regulates NF-κB. IKKβ and NF-κB are required in vivo for prevention of TNFα-mediated apoptosis. ML120B sensitized mouse bone marrow progenitors and granulocytes, but not mature B cells to TNFα killing in vitro, and induced apoptosis in vivo in the bone marrow and spleen within 6 hours of a single oral dose. In vivo inhibition of IKKβ with ML120B resulted in depletion of thymocytes and B cells in all stages of development in the bone marrow but did not deplete granulocytes. TNF receptor–deficient mouse thymocytes and B cells were resistant to ML120B-induced depletion in vivo. Surprisingly, surviving bone marrow granulocytes expressed TNFR1 and TNFR2 after dosing in vivo with ML120B. Our results show that inhibition of IKKβ with a small molecule in vivo leads to rapid TNF-dependent depletion of T and B cells. This observation has several implications for potential use of IKKβ inhibitors for the treatment of inflammatory disease and cancer.

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Small molecule inhibition of IRE1α kinase/RNase has anti-fibrotic effects in the lung

10.1101/398552 ◽

2018 ◽

Author(s):

Maike Thamsen ◽

Rajarshi Ghosh ◽

Vincent C. Auyeung ◽

Alexis Brumwell ◽

Harold A. Chapman ◽

...

Keyword(s):

Pulmonary Fibrosis ◽

Er Stress ◽

Small Molecule ◽

Kinase Inhibitors ◽

Alveolar Epithelial Cells ◽

Alveolar Epithelial ◽

Induced Apoptosis ◽

The Unfolded Protein Response

AbstractEndoplasmic reticulum stress (ER stress) has been implicated in the pathogenesis of idiopathic pulmonary fibrosis (IPF), a disease of progressive fibrosis and respiratory failure. ER stress activates a signaling pathway called the unfolded protein response (UPR) that either restores homeostasis or promotes apoptosis. The bifunctional kinase/RNase IRE1α is a UPR sensor that promotes apoptosis if ER stress remains high (i.e., a “terminal” UPR). Using multiple small molecule inhibitors against IRE1α, we show that ER stress-induced apoptosis of murine alveolar epithelial cells can be mitigated in vitro. In vivo, we show that bleomycin exposure to murine lungs causes early ER stress to activate IRE1α and the terminal UPR prior to development of pulmonary fibrosis. Small-molecule IRE1α kinase-inhibiting RNase attenuators (KIRAs) that we developed were used to evaluate the importance of IRE1α activation in bleomycin-induced pulmonary fibrosis. One such KIRA—KIRA7—provided systemically to mice at the time of bleomycin exposure decreases terminal UPR signaling and prevents lung fibrosis. Administration of KIRA7 14 days after bleomycin exposure even promoted the reversal of established fibrosis. Finally, we show that KIRA8, a nanomolar-potent, monoselective KIRA compound derived from a completely different scaffold than KIRA7, likewise promoted reversal of established fibrosis. These results demonstrate that IRE1α may be a promising target in pulmonary fibrosis and that kinase inhibitors of IRE1α may eventually be developed into efficacious anti-fibrotic drugs.

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LLL12B, a small molecule STAT3 inhibitor, induces growth arrest, apoptosis, and enhances cisplatin-mediated cytotoxicity in medulloblastoma cells

Scientific Reports ◽

10.1038/s41598-021-85888-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Xiang Chen ◽

Li Pan ◽

Jia Wei ◽

Ruijie Zhang ◽

Xiaozhi Yang ◽

...

Keyword(s):

Tumor Growth ◽

Small Molecule ◽

Single Agent ◽

Stat3 Signaling ◽

Molecule Inhibitor ◽

Stat3 Phosphorylation ◽

Induced Apoptosis ◽

Transcription 3

AbstractSignal Transducer and Activator of Transcription 3 (STAT3) is a transcription factor and an oncogene product, which plays a pivotal role in tumor progression. Therefore, targeting persistent STAT3 signaling directly is an attractive anticancer strategy. The aim of this study is to test the efficacy of a novel STAT3 small molecule inhibitor, LLL12B, in suppressing medulloblastoma cells in vitro and tumor growth in vivo. LLL12B selectively inhibited the induction of STAT3 phosphorylation by interleukin-6 but not induction of STAT1 phosphorylation by INF-γ. LLL12B also induced apoptosis in human medulloblastoma cells. In addition, LLL12B exhibited good oral bioavailability in vivo and potent suppressive activity in tumor growth of medulloblastoma cells in vivo. Besides, combining LLL12B with cisplatin showed greater inhibition of cell viability and tumorsphere formation as well as induction of apoptosis comparing to single agent treatment in medulloblastoma cells. Furthermore, LLL12B and cisplatin combination exhibited greater suppression of medulloblastoma tumor growth than monotherapy in vivo. The present study supported that LLL12B is a novel therapeutic agent for medulloblastoma and the combination of LLL12B with a chemotherapeutic agent cisplatin may be an effective approach for medulloblastoma therapy.

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Faculty Opinions recommendation of Identification of new small molecule inhibitors of cystic fibrosis transmembrane conductance regulator protein: in vitro and in vivo studies.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1069767.522696 ◽

2007 ◽

Author(s):

Kim Barrett

Keyword(s):

Cystic Fibrosis ◽

Small Molecule ◽

Small Molecule Inhibitors ◽

In Vivo Studies ◽

Transmembrane Conductance Regulator ◽

Transmembrane Conductance ◽

Regulator Protein ◽

Cystic Fibrosis Transmembrane

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Exosomal Vimentin from Adipocyte Progenitors Protects Fibroblasts against Osmotic Stress and Inhibits Apoptosis to Enhance Wound Healing

International Journal of Molecular Sciences ◽

10.3390/ijms22094678 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4678

Author(s):

Sepideh Parvanian ◽

Hualian Zha ◽

Dandan Su ◽

Lifang Xi ◽

Yaming Jiu ◽

...

Keyword(s):

Wound Healing ◽

Osmotic Stress ◽

Mechanical Stress ◽

Impaired Wound Healing ◽

In Vivo Experiments ◽

Adipocyte Progenitors ◽

Osmotic Balance ◽

Induced Apoptosis

Mechanical stress following injury regulates the quality and speed of wound healing. Improper mechanotransduction can lead to impaired wound healing and scar formation. Vimentin intermediate filaments control fibroblasts’ response to mechanical stress and lack of vimentin makes cells significantly vulnerable to environmental stress. We previously reported the involvement of exosomal vimentin in mediating wound healing. Here we performed in vitro and in vivo experiments to explore the effect of wide-type and vimentin knockout exosomes in accelerating wound healing under osmotic stress condition. Our results showed that osmotic stress increases the size and enhances the release of exosomes. Furthermore, our findings revealed that exosomal vimentin enhances wound healing by protecting fibroblasts against osmotic stress and inhibiting stress-induced apoptosis. These data suggest that exosomes could be considered either as a stress modifier to restore the osmotic balance or as a conveyer of stress to induce osmotic stress-driven conditions.

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iPLA2β Contributes to ER Stress-Induced Apoptosis during Myocardial Ischemia/Reperfusion Injury

Cells ◽

10.3390/cells10061446 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1446

Author(s):

Tingting Jin ◽

Jun Lin ◽

Yingchao Gong ◽

Xukun Bi ◽

Shasha Hu ◽

...

Keyword(s):

Cell Death ◽

Heart Disease ◽

Myocardial Ischemia ◽

Ischemic Heart Disease ◽

Er Stress ◽

Ischemia Reperfusion ◽

Myocardial Ischemia Reperfusion ◽

Induced Apoptosis

Both calcium-independent phospholipase A2 beta (iPLA2β) and endoplasmic reticulum (ER) stress regulate important pathophysiological processes including inflammation, calcium homeostasis and apoptosis. However, their roles in ischemic heart disease are poorly understood. Here, we show that the expression of iPLA2β is increased during myocardial ischemia/reperfusion (I/R) injury, concomitant with the induction of ER stress and the upregulation of cell death. We further show that the levels of iPLA2β in serum collected from acute myocardial infarction (AMI) patients and in samples collected from both in vivo and in vitro I/R injury models are significantly elevated. Further, iPLA2β knockout mice and siRNA mediated iPLA2β knockdown are employed to evaluate the ER stress and cell apoptosis during I/R injury. Additionally, cell surface protein biotinylation and immunofluorescence assays are used to trace and locate iPLA2β. Our data demonstrate the increase of iPLA2β augments ER stress and enhances cardiomyocyte apoptosis during I/R injury in vitro and in vivo. Inhibition of iPLA2β ameliorates ER stress and decreases cell death. Mechanistically, iPLA2β promotes ER stress and apoptosis by translocating to ER upon myocardial I/R injury. Together, our study suggests iPLA2β contributes to ER stress-induced apoptosis during myocardial I/R injury, which may serve as a potential therapeutic target against ischemic heart disease.

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A small molecule HIF-1α stabilizer that accelerates diabetic wound healing

Nature Communications ◽

10.1038/s41467-021-23448-7 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Guodong Li ◽

Chung-Nga Ko ◽

Dan Li ◽

Chao Yang ◽

Wanhe Wang ◽

...

Keyword(s):

Wound Healing ◽

Small Molecule ◽

Hypoxia Inducible Factor ◽

Diabetic Patients ◽

Diabetic Mice ◽

Impaired Wound Healing ◽

Von Hippel Lindau ◽

Design And Synthesis

AbstractImpaired wound healing and ulcer complications are a leading cause of death in diabetic patients. In this study, we report the design and synthesis of a cyclometalated iridium(III) metal complex 1a as a stabilizer of hypoxia-inducible factor-1α (HIF-1α). In vitro biophysical and cellular analyses demonstrate that this compound binds to Von Hippel-Lindau (VHL) and inhibits the VHL–HIF-1α interaction. Furthermore, the compound accumulates HIF-1α levels in cellulo and activates HIF-1α mediated gene expression, including VEGF, GLUT1, and EPO. In in vivo mouse models, the compound significantly accelerates wound closure in both normal and diabetic mice, with a greater effect being observed in the diabetic group. We also demonstrate that HIF-1α driven genes related to wound healing (i.e. HSP-90, VEGFR-1, SDF-1, SCF, and Tie-2) are increased in the wound tissue of 1a-treated diabetic mice (including, db/db, HFD/STZ and STZ models). Our study demonstrates a small molecule stabilizer of HIF-1α as a promising therapeutic agent for wound healing, and, more importantly, validates the feasibility of treating diabetic wounds by blocking the VHL and HIF-1α interaction.

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Discovery of vanoxerine dihydrochloride as a CDK2/4/6 triple-inhibitor for the treatment of human hepatocellular carcinoma

Molecular Medicine ◽

10.1186/s10020-021-00269-4 ◽

2021 ◽

Vol 27 (1) ◽

Author(s):

Ying Zhu ◽

Kun-Bin Ke ◽

Zhong-Kun Xia ◽

Hong-Jian Li ◽

Rong Su ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Cell Cycle Progression ◽

G1 Arrest ◽

Huh7 Cells ◽

Synergistic Cytotoxicity ◽

Combination Study ◽

Experimental Approaches ◽

Induced Apoptosis

Abstract Background Cyclin-dependent kinases 2/4/6 (CDK2/4/6) play critical roles in cell cycle progression, and their deregulations are hallmarks of hepatocellular carcinoma (HCC). Methods We used the combination of computational and experimental approaches to discover a CDK2/4/6 triple-inhibitor from FDA approved small-molecule drugs for the treatment of HCC. Results We identified vanoxerine dihydrochloride as a new CDK2/4/6 inhibitor, and a strong cytotoxicdrugin human HCC QGY7703 and Huh7 cells (IC50: 3.79 μM for QGY7703and 4.04 μM for Huh7 cells). In QGY7703 and Huh7 cells, vanoxerine dihydrochloride treatment caused G1-arrest, induced apoptosis, and reduced the expressions of CDK2/4/6, cyclin D/E, retinoblastoma protein (Rb), as well as the phosphorylation of CDK2/4/6 and Rb. Drug combination study indicated that vanoxerine dihydrochloride and 5-Fu produced synergistic cytotoxicity in vitro in Huh7 cells. Finally, in vivo study in BALB/C nude mice subcutaneously xenografted with Huh7 cells, vanoxerine dihydrochloride (40 mg/kg, i.p.) injection for 21 days produced significant anti-tumor activity (p < 0.05), which was comparable to that achieved by 5-Fu (10 mg/kg, i.p.), with the combination treatment resulted in synergistic effect. Immunohistochemistry staining of the tumor tissues also revealed significantly reduced expressions of Rb and CDK2/4/6in vanoxerinedihydrochloride treatment group. Conclusions The present study isthe first report identifying a new CDK2/4/6 triple inhibitor vanoxerine dihydrochloride, and demonstrated that this drug represents a novel therapeutic strategy for HCC treatment.

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