Contribution of TNF-α to Leukocyte Adhesion, Vascular Leakage, and Apoptotic Cell Death in Endotoxin-Induced Uveitis In Vivo

Shiga toxin (Stx)-mediated immune responses, including the production of the proinflammatory cytokines tumor necrosis-α (TNF-α) and interleukin-1β (IL-1β), may exacerbate vascular damage and accelerate lethality. However, the immune signaling pathway activated in response to Stx is not well understood. Here, we demonstrate that enzymatically active Stx, which leads to ribotoxic stress, triggers NLRP3 inflammasome-dependent caspase-1 activation and IL-1β secretion in differentiated macrophage-like THP-1 (D-THP-1) cells. The treatment of cells with a chemical inhibitor of glycosphingolipid biosynthesis, which suppresses the expression of the Stx receptor globotriaosylceramide and subsequent endocytosis of the toxin, substantially blocked activation of the NLRP3 inflammasome and processing of caspase-1 and IL-1β. Processing and release of both caspase-1 and IL-1β were significantly reduced or abolished in Stx-intoxicated D-THP-1 cells in which the expression of NLRP3 or ASC was stably knocked down. Furthermore, Stx mediated the activation of caspases involved in apoptosis in an NLRP3- or ASC-dependent manner. In Stx-intoxicated cells, the NLRP3 inflammasome triggered the activation of caspase-8/3, leading to the initiation of apoptosis, in addition to caspase-1-dependent pyroptotic cell death. Taken together, these results suggest that Stxs trigger the NLRP3 inflammasome pathway to release proinflammatory IL-1β as well as to promote apoptotic cell death.

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O-GlcNAc Transferase Inhibitor Synergistically Enhances Doxorubicin-Induced Apoptosis in HepG2 Cells

Cancers ◽

10.3390/cancers12113154 ◽

2020 ◽

Vol 12 (11) ◽

pp. 3154

Author(s):

Su Jin Lee ◽

Oh-Shin Kwon

Keyword(s):

Hepatocellular Carcinoma ◽

Cell Death ◽

Hepg2 Cells ◽

Drug Targets ◽

Apoptotic Cell ◽

Chemotherapy Resistance ◽

Apoptotic Cell Death ◽

Induced Apoptosis ◽

Glcnac Transferase

The combination of chemotherapy with chemosensitizing agents is a common approach to enhance anticancer activity while reducing the dose-dependent adverse side effects of cancer treatment. Herein, we investigated doxorubicin (DOX) and O-GlcNAc transferase (OGT) inhibitor OSMI-1 combination treatment, which significantly enhanced apoptosis in hepatocellular carcinoma cells (HepG2) as a result of synergistic drug action in disparate stress signaling pathways. Treatment with a low dose of DOX or a suboptimal dose of OSMI-1 alone did not induce apoptotic cell death in HepG2 cells. However, the combination of DOX with OSMI-1 in HepG2 cells synergistically increased apoptotic cell death through the activation of both the p53 and mitochondrial Bcl2 pathways compared to DOX alone. We also demonstrated that the combination of DOX and OSMI-1 stimulated cell death, dramatically reducing cell proliferation and tumor growth in vivo using a HepG2 xenograft mouse model. These findings indicate that OSMI-1 acts as a potential chemosensitizer by enhancing DOX-induced cell death. This study provides insight into a possible mechanism of chemotherapy resistance, identifies potential novel drug targets, and suggests that OGT inhibition could be utilized in clinical applications to treat hepatocellular carcinoma as well as other cancer types.

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Angiotensin II Type 1 Receptor Blockade Does Not Enhance Apoptotic Cell Death During Ischemia and Reperfusion in Humans In Vivo

Journal of Cardiovascular Pharmacology ◽

10.1097/fjc.0b013e318218ef21 ◽

2011 ◽

Vol 57 (6) ◽

pp. 702-706 ◽

Cited By ~ 3

Author(s):

Patrick Meijer ◽

Constantijn W Wouters ◽

Wim J Oyen ◽

Otto C Boerman ◽

Gert Jan Scheffer ◽

...

Keyword(s):

Cell Death ◽

Angiotensin Ii ◽

Apoptotic Cell ◽

Apoptotic Cell Death ◽

Receptor Blockade ◽

Ischemia And Reperfusion

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Pheophorbideï¿½a-mediated photodynamic therapy induces apoptotic cell death in murine oral squamous cell carcinoma in vitro and in vivo

Oncology Reports ◽

10.3892/or.2012.1748 ◽

2012 ◽

Cited By ~ 1

Author(s):

Sang-Gun Ahn

Keyword(s):

Squamous Cell Carcinoma ◽

Cell Death ◽

Photodynamic Therapy ◽

Oral Squamous Cell Carcinoma ◽

Cell Carcinoma ◽

Squamous Cell ◽

Apoptotic Cell ◽

Apoptotic Cell Death

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In vivo suppression of myocardial apoptotic cell death by insulin-like growth factor IGF I and II

Journal of the American College of Cardiology ◽

10.1016/s0735-1097(98)80932-7 ◽

1998 ◽

Vol 31 ◽

pp. 66

Author(s):

M. Scheinowitz ◽

G. Sangiorgi ◽

L.G. Spagnoli ◽

A. Orlandi ◽

A. Kellyar ◽

...

Keyword(s):

Cell Death ◽

Growth Factor ◽

Apoptotic Cell ◽

Apoptotic Cell Death ◽

Insulin Like Growth Factor ◽

Igf I

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Activity of MK1775, a selective Wee1 inhibitor, alone or in combination with gemcitabine, in sarcomas.

Journal of Clinical Oncology ◽

10.1200/jco.2012.30.15_suppl.10084 ◽

2012 ◽

Vol 30 (15_suppl) ◽

pp. 10084-10084

Author(s):

Jenny Kreahling ◽

Damon R. Reed ◽

Parastou Foroutan ◽

Gary Martinez ◽

Robert Gillies ◽

...

Keyword(s):

Cell Cycle ◽

Cell Death ◽

Soft Tissue ◽

Soft Tissue Sarcoma ◽

Therapeutic Efficacy ◽

Ex Vivo ◽

Apoptotic Cell ◽

Apoptotic Cell Death ◽

Primary Therapy

10084 Background: Sarcomas consist of more than 50 subtypes of mesenchymal tumors. Doxorubicin alone or in combination has been the primary therapy for treatment of sarcomas; however, the response rates are suboptimal in many of the more common adult subtypes of soft tissue sarcoma. Accordingly, new agents are needed for the treatment of this heterogeneous group of diseases. Wee1 is a critical component of the G2/M cell cycle checkpoint control and mediates cell cycle arrest by regulating the phosphorylation of CDC2. Methods: MK1775 treatment of multiple sarcoma preclinical models at clinically relevant concentrations leads to unscheduled entry into mitosis and initiation of apoptotic cell death. In our current study we have investigated the therapeutic efficacy of MK1775 in sarcoma cell lines, patient-derived tumor explants ex vivo and in vivo in a xenograft model of osteosarcoma both alone and in combination with gemcitabine. Results: In patient-derived bone and soft tissue sarcoma samples ex vivo treatments show MK1775 in combination with gemcitabine causes significant apoptotic cell death suggesting that this treatment may represent a novel approach in the treatment of sarcomas. The cytotoxic effect of Wee1 inhibition on sarcoma cells appears to be independent of p53 mutational status. Furthermore, in a patient-derived osteosarcoma xenograft mouse model we show the therapeutic efficacy of MK1775 in vivo by utilizing magnetic resonance imaging (MRI) and diffusion MRI methods. Our data shows MK1775 in combination with gemcitabine dramatically slows tumor growth, increases apoptotic cell death and increases CDC2 activity. Cell viability, a clinically established prognostic indicator of survival, was lowest with the combination and very low in animals treated with MK1775 alone. This was mainly due to increased mineralization of the tumors. Caspase-3 was increased in MK1775 treated animals by immunohistochemistry as well. Conclusions: These results together with the promising safety profile of MK1775 strongly suggest that this drug can be used as a potential therapeutic agent alone or in combination with gemcitabine in the treatment of both adult as well as pediatric sarcoma patients.

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Sindbis Virus-Induced Neuronal Death Is both Necrotic and Apoptotic and Is Ameliorated byN-Methyl-d-Aspartate Receptor Antagonists

Journal of Virology ◽

10.1128/jvi.75.15.7114-7121.2001 ◽

2001 ◽

Vol 75 (15) ◽

pp. 7114-7121 ◽

Cited By ~ 70

Author(s):

Jennifer L. Nargi-Aizenman ◽

Diane E. Griffin

Keyword(s):

Cell Death ◽

Cortical Neurons ◽

Sindbis Virus ◽

Apoptotic Cell ◽

Time Lapse ◽

Apoptotic Cell Death ◽

Time Lapse Imaging ◽

Alphavirus Infection

ABSTRACT Virus infection of neurons leads to different outcomes ranging from latent and noncytolytic infection to cell death. Viruses kill neurons directly by inducing either apoptosis or necrosis or indirectly as a result of the host immune response. Sindbis virus (SV) is an alphavirus that induces apoptotic cell death both in vitro and in vivo. However, apoptotic changes are not always evident in neurons induced to die by alphavirus infection. Time lapse imaging revealed that SV-infected primary cortical neurons exhibited both apoptotic and necrotic morphological features and that uninfected neurons in the cultures also died. Antagonists of the N-methyl-d-aspartate (NMDA) subtype of glutamate receptors protected neurons from SV-induced death without affecting virus replication or SV-induced apoptotic cell death. These results provide evidence that SV infection activates neurotoxic pathways that result in aberrant NMDA receptor stimulation and damage to infected and uninfected neurons.

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