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Generation of Lymphocytic Microparticles and Detection of their Proapoptotic Effect on Airway Epithelial Cells
Published on: February 20, 2015
Activated endothelial cells induce apoptosis in lymphoma cells
V Umansky1, M Bucur, V Schirrmacher
1GERMAN CANC RES CTR,DIV CELLULAR IMMUNOL,TUMOR IMMUNOL PROGRAM,D-6900 HEIDELBERG,GERMANY.
International Journal of Oncology
|May 3, 2011
Summary
Activated endothelial cells produce nitric oxide (NO), which kills metastatic lymphoma cells in vitro. This NO-mediated cytotoxicity involves inducing apoptosis, revealing a novel role for endothelial cells in eliminating cancer metastasis.
Area of Science:
- Immunology
- Cell Biology
- Oncology
Background:
- Previous studies indicated nitric oxide (NO) production by liver endothelial cells is linked to the regression of liver metastases.
- The role of endothelial cells in directly eliminating metastatic cancer cells requires further investigation.
Purpose of the Study:
- To investigate the in vitro nitric oxide (NO)-mediated cytotoxicity of endothelial cells against metastatic lymphoma cells.
- To elucidate the mechanism of NO-induced tumor cell death and the role of apoptosis.
Main Methods:
- Co-culture of activated bovine endothelial cells (BEC) with ESbL-lacZ lymphoma cells.
- Measurement of NO synthesis and inhibition using N-G-monomethyl-L-arginine (NMMA).
- Assessment of tumor cell death via propidium iodide staining and Flow-Assisted Genetic Sorting (FAGS) analysis; induction of apoptosis.
Main Results:
- Activated BEC significantly increased NO production upon stimulation with TNF-alpha, which was blocked by NMMA.
- Activated BEC exhibited cytotoxicity against metastatic lymphoma cells, evidenced by cell death.
- This cytotoxicity was reduced by NMMA pretreatment and mimicked by NO donor glycerol trinitrate (GTN), indicating NO's crucial role.
- Activated BEC induced apoptosis in lymphoma cells, largely mediated by NO.
Conclusions:
- Endothelial cells, when activated, can exert NO-mediated cytotoxicity against metastatic lymphoma cells.
- Nitric oxide plays a significant role in inducing apoptosis in tumor cells, contributing to anti-metastatic effects.
- Endothelial cells possess a novel function in eliminating metastatic cells through the induction of programmed cell death.
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