Up-regulation of BLT2 is critical for the survival of bladder cancer cells.
10.3858/emm.2011.43.3.014
- Author:
Ji Min SEO
1
;
Kyung Jin CHO
;
Eun Young KIM
;
Man Ho CHOI
;
Bong Chul CHUNG
;
Jae Hong KIM
Author Information
1. School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea. jhongkim@korea.ac.kr
- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
- Keywords:
biological markers;
cell survival;
LTB4R2 protein, human;
NADPH oxidase;
reactive oxygen species;
urinary bladder neoplasms
- MeSH:
*Apoptosis;
Blotting, Western;
Cell Proliferation;
Cells, Cultured;
Gene Expression Regulation, Neoplastic/*physiology;
Humans;
Leukotriene Antagonists/pharmacology;
NADPH Oxidase/antagonists & inhibitors/genetics/metabolism;
Phosphorylation;
RNA, Messenger/genetics;
RNA, Small Interfering/genetics;
Reactive Oxygen Species/*metabolism;
Receptors, Leukotriene B4/antagonists & inhibitors/*genetics;
Reverse Transcriptase Polymerase Chain Reaction;
Signal Transduction;
Tetrazoles/pharmacology;
Up-Regulation;
Urinary Bladder Neoplasms/*genetics/mortality
- From:Experimental & Molecular Medicine
2011;43(3):129-137
- CountryRepublic of Korea
- Language:English
-
Abstract:
The incidence rates of urinary bladder cancer continue to rise yearly, and thus new therapeutic approaches and early diagnostic markers for bladder cancer are urgently needed. Thus, identifying the key mediators and molecular mechanisms responsible for the survival of bladder cancer has valuable implications for the development of therapy. In this study, the role of BLT2, a receptor for leukotriene B4 (LTB4) and 12(S)-hydroxyeicosatetraenoic acid (HETE), in the survival of bladder cancer 253J-BV cells was investigated. We found that the expression of BLT2 is highly elevated in bladder cancer cells. Also, we observed that blockade of BLT2 with an antagonist or BLT2 siRNA resulted in cell cycle arrest and apoptotic cell death, suggesting a role of BLT2 in the survival of human bladder cancer 253J-BV cells. Further experiments aimed at elucidating the mechanism by which BLT2 mediates survival revealed that enhanced level of reactive oxygen species (ROS) are generated via a BLT2-dependent up-regulation of NADPH oxidase members NOX1 and NOX4. Additionally, we observed that inhibition of ROS generation by either NOX1/4 siRNAs or treatment with an ROS-scavenging agent results in apoptotic cell death in 253J-BV bladder cancer cells. These results demonstrated that a 'BLT2-NOX1/4-ROS' cascade plays a role in the survival of this aggressive bladder cancer cells, thus pointing to BLT2 as a potential target for anti-bladder cancer therapy.
