5'-Nitro-indirubinoxime induces G1 cell cycle arrest and apoptosis in salivary gland adenocarcinoma cells through the inhibition of Notch-1 signaling.

Abstract

BACKGROUND:

5'-Nitro-indirubinoxime (5'-NIO) is a new derivative of indirubin that exhibits anti-cancer activity in a variety of human cancer cells. However, its mechanism has not been fully clarified.

METHODS:

Human salivary gland adenocarcinoma (SGT) cells were used in this study. Western blot and RT-PCR analyses were performed to determine cellular Notch levels. The cell cycle stage and level of apoptosis were analyzed using flow cytometry analysis.

RESULTS:

5'-NIO significantly inhibited the mRNA levels of Notch-1 and Notch-3 and their ligands (Delta1, 2, 3, and Jagged-2) in SGT cells. Immunocytochemistry analysis showed that 5'-NIO specifically decreased the level of Notch-1 in the nucleus. In addition, 5'-NIO induced G1 cell cycle arrest by reducing levels of CDK4 and CDK6 in SGT cells. Using flow cytometry and immunoblotting analysis, we found that 5'-NIO induces apoptosis following the secretion of cytochrome c and the activation of caspase-3 and caspase-7. Intracellular Notch-1 overexpression led to a decrease in G1 phase arrest and an inhibition of 5'-NIO-induced apoptosis.

CONCLUSION:

These observations suggest that 5'-NIO induces cell cycle arrest and apoptosis by down-regulating Notch-1 signaling.

GENERAL SIGNIFICANCE:

This study identifies a new mechanism of 5'-NIO-mediated anti-tumor properties. Thus, 5'-NIO could be used as a candidate for salivary gland adenocarcinoma therapeutics.

• Authors: Ji-Hye Yoon, Soo-A Kim, Seong-Min Kwon, Jong-Hwan Park, Hee-Sae Park, Yong-Chul Kim, Jung-Hoon Yoon, Sang-Gun Ahn
• Journal: Biochimica et biophysica acta (Biochim Biophys Acta) Vol. 1800 Issue 3 Pg. 352-8 (Mar 2010) ISSN: 0006-3002 [Print] Netherlands
• PMID: 19914349 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright (c) 2009 Elsevier B.V. All rights reserved.

Chemical References

• 5'-nitroindirubinoxime
• DNA Primers
• Indoles
• NOTCH1 protein, human
• Oximes
• Receptor, Notch1

Topics

• Adenocarcinoma (pathology)
• Apoptosis (drug effects)
• Cell Cycle (drug effects)
• Cell Division (drug effects)
• Cell Line, Tumor
• DNA Primers
• Flow Cytometry
• Gene Expression Regulation, Neoplastic (drug effects)
• Humans
• Indoles (pharmacology)
• Oximes (pharmacology)
• Promoter Regions, Genetic
• Receptor, Notch1 (drug effects, genetics, physiology)
• Reverse Transcriptase Polymerase Chain Reaction
• Salivary Gland Neoplasms (pathology)