Calcium regulates caveolin-1 expression at the transcriptional level
Xiao-Yan Yang1, Cheng-Cheng Huang, Qi-Ming Kan
1Laboratory of Tumor Biology and Glycobiology, Department of Life Sciences, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China.
Biochemical and Biophysical Research Communications
|September 4, 2012
Summary
Calcium signaling positively regulates caveolin-1 expression. This pathway involves L-type calcium channels, calcineurin, and nuclear factor of activated T-cells (NFAT), impacting osteosarcoma metastasis.
Area of Science:
- Molecular Biology
- Cell Signaling
- Cancer Research
Background:
- Caveolin-1, a transformation suppressor protein, shows differential expression in osteosarcoma metastasis.
- Poorly metastatic osteosarcoma cells exhibit higher caveolin-1 and calcium levels than highly metastatic cells.
Purpose of the Study:
- To investigate the role of calcium signaling in regulating caveolin-1 expression.
- To elucidate the novel pathway mediating caveolin-1 transcriptional regulation.
Main Methods:
- Pharmacological inhibition of calcium channels (nifedipine) and signaling molecules (cyclosporin A, INCA-6).
- RNA silencing of the L-type calcium channel subunit alpha-1C.
- Analysis of caveolin-1 mRNA and protein levels.
Main Results:
- Inhibition of calcium signaling components decreased caveolin-1 expression at both mRNA and protein levels.
- Silencing of the L-type calcium channel subunit suppressed caveolin-1 expression.
- The identified pathway was conserved across different cell types.
Conclusions:
- Caveolin-1 is transcriptionally upregulated via a novel calcium signaling pathway.
- This pathway involves L-type calcium channel, intracellular calcium, calcineurin, and NFAT.
- Understanding this pathway may offer therapeutic targets for osteosarcoma metastasis.
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