Characterization of choline kinase in human endothelial cells.

Abstract

High choline kinase-α (Chk-α) expression is frequently observed in cancer cells, making it a novel target for pharmacological and molecular inhibition. As inhibiting agents are delivered systemically, it is important to determine Chk-α expression levels in endothelial cells that line both normal and tumor vasculature, and the effect of Chk-α downregulation on these cells. Here, we characterized Chk-α expression and the effect of its downregulation in human umbilical vein endothelial cells (HUVECs) relative to MDA-MB-231 human breast cancer cells. We used small interfering RNA (siRNA) to downregulate Chk-α expression. Basal mRNA levels of Chk-α were approximately three-fold lower in HUVECs relative to MDA-MB-231 breast cancer cells. Consistent with the differences in Chk-α protein levels, phosphocholine levels were approximately 10-fold lower in HUVECs relative to MDA-MB-231 cells. Transient transfection with siRNA-Chk resulted in comparable levels of mRNA and protein in MDA-MB-231 breast cancer cells and HUVECs. However, there was a significant reduction in proliferation in MDA-MB-231 cells, but not in HUVECs. No significant difference in CD31 immunostaining was observed in tumor sections obtained from mice injected with control luciferase-short hairpin (sh)RNA or Chk-shRNA lentivirus. These data suggest that systemically delivered agents that downregulate Chk-α in tumors will not affect endothelial cell proliferation during delivery, and further support the development of Chk-α downregulation as a cancer-specific treatment.

• Authors: Noriko Mori, Mayur Gadiya, Flonné Wildes, Balaji Krishnamachary, Kristine Glunde, Zaver M Bhujwalla
• Journal: NMR in biomedicine (NMR Biomed) Vol. 26 Issue 11 Pg. 1501-7 (Nov 2013) ISSN: 1099-1492 [Electronic] England
• PMID: 23775813 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)
• Copyright: Copyright © 2013 John Wiley & Sons, Ltd.

Chemical References

• Cell Extracts
• RNA, Messenger
• RNA, Small Interfering
• Choline Kinase

Topics

• Animals
• Cell Extracts
• Cell Line, Tumor
• Cell Proliferation
• Cell Survival
• Choline Kinase (genetics, metabolism)
• Down-Regulation
• Gene Expression Regulation, Enzymologic
• Human Umbilical Vein Endothelial Cells (cytology, enzymology)
• Humans
• Magnetic Resonance Spectroscopy
• Mice
• RNA, Messenger (genetics, metabolism)
• RNA, Small Interfering (metabolism)
• Real-Time Polymerase Chain Reaction
• Transfection