NFAT3 is specifically required for TNF-alpha-induced cyclooxygenase-2 (COX-2) expression and transformation of Cl41 cells.

Abstract

NFAT family is recognized as a transcription factor for inflammation regulation by inducing the expression of proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha), the key mediator of inflammation, which was reported to induce cell transformation in mouse epidermal Cl41 cells. In this study, we demonstrated that TNF-alpha was able to induce NFAT activation, as well as the expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). The induction of COX-2 by TNF-alpha was abolished by knockdown of NFAT3 with its siRNA, while the induction of iNOS was not effected. Moreover, TNF-alpha-induced anchorage-independent cell growth was significantly inhibited by NFAT3 siRNA and cyclosporine A, a chemical inhibitor for the calcineurin/NFAT pathway, which suggests the importance of NFAT3 in regulating TNF-alpha-induced anchorage-independent cell growth. Consequently, impairment of COX-2 by its siRNA or selective inhibitor also inhibited TNF-alpha-induced anchorage-independent cell growth. Taken together, our results indicate that NFAT3 plays an important role in the regulation of TNF-alpha-induced anchorage-independent cell growth, at least partially, by inducing COX-2 expression in Cl41 cells. These findings suggest that NFAT3/cyclooxygenase-2 act as a link between inflammation and carcinogenesis by being involved in the tumor promotion stage.

• Authors: Yan Yan, Jingxia Li, Weiming Ouyang, Qian Ma, Yu Hu, Dongyun Zhang, Jin Ding, Qingshan Qu, Kotha Subbaramaiah, Chuanshu Huang
• Journal: Journal of cell science (J Cell Sci) Vol. 119 Issue Pt 14 Pg. 2985-94 (Jul 15 2006) ISSN: 0021-9533 [Print] England
• PMID: 16803872 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)

Chemical References

• NFATC Transcription Factors
• Tumor Necrosis Factor-alpha
• Nitric Oxide Synthase Type II
• Cyclooxygenase 2

Topics

• Animals
• Cell Line
• Cell Transformation, Neoplastic (drug effects)
• Cyclooxygenase 2 (biosynthesis)
• Enzyme Induction (drug effects)
• Epidermal Cells
• Epidermis (drug effects, enzymology)
• Gene Expression Regulation, Enzymologic (drug effects)
• Humans
• Mice
• NFATC Transcription Factors (metabolism)
• Nitric Oxide Synthase Type II (biosynthesis)
• Promoter Regions, Genetic (drug effects)
• Tumor Necrosis Factor-alpha (pharmacology)