LPS-induced nuclear translocation of RhoA is dependent on NF-κB in the human lung cancer cell line A549
Open Access
- 2 April 2012
- journal article
- Published by Spandidos Publications in Oncology Letters
- Vol. 3 (6), 1283-1287
- https://doi.org/10.3892/ol.2012.667
Abstract
RhoA, an extensively studied member of the Rho GTPase family, has been identified as a mediator of pro-inflammatory responses and aggressive carcinogenesis. Bacterial lipopolysaccharide (LPS) is known to be a potent stimulator of inflammatory cytokine production. LPS is able to alter the activity of RhoA and the subcellular distribution of RhoA is altered according to its activity. In this study, we investigated a possible link between RhoA and the LPS/nuclear factor (NF)-κB signaling pathway. In the present study, western blotting and pull-down and immunofluorescence assays were performed to investigate the activity of RhoA in A549 cells following LPS stimulation. The results showed that LPS was able to activate RhoA. Furthermore, western blotting and an immunofluorescence assay were carried out to investigate the nuclear expression of RhoA in A549 cells following LPS stimulation. The results indicated that LPS triggers the nuclear translocation of RhoA. Furthermore, western blotting, NF-κB small interfering RNA (siRNA) transfection and an immunofluorescence assay were performed to investigate the role of NF-κB in LPS-induced RhoA nuclear translocation in A549 cells. The results showed that LPS-induced RhoA nuclear translocation was inhibited by NF-κB depletion in A549 cells. RhoA and NF-κB siRNA transfection, western blotting and ELISA were carried out to investigate the role of RhoA in the LPS-induced secretion of interleukin (IL)-6 and IL-8 in A549 cells. The depletion of RhoA using RhoA siRNA decreased the LPS-induced secretion of IL-6 and IL-8, similar to the effect of NF-κB depletion. These results demonstrate that LPS is able to activate RhoA and trigger its nuclear translocation, which is dependent on NF-κB, and that RhoA plays a significant role in the LPS/NF-κB signaling pathway.Keywords
This publication has 21 references indexed in Scilit:
- Characterization of the roles of RHOC and RHOA GTPases in invasion, motility, and matrix adhesion in inflammatory and aggressive breast cancersCancer, 2010
- Rho Kinase-2 Activation in Human Endothelial Cells Drives Lysophosphatidic Acid-mediated Expression of Cell Adhesion Molecules via NF-κB p65Online Journal of Public Health Informatics, 2010
- Localization and translocation of RhoA protein in the human gastric cancer cell line SGC-7901World Journal of Gastroenterology, 2008
- Influence of human Ect2 depletion and overexpression on cleavage furrow formation and abscissionJournal of Cell Science, 2006
- GDIs: central regulatory molecules in Rho GTPase activationTrends in Cell Biology, 2005
- GEF means go: turning on RHO GTPases with guanine nucleotide-exchange factorsNature Reviews Molecular Cell Biology, 2005
- NF-κB regulation in the immune systemNature Reviews Immunology, 2002
- The Rho Exchange Factor Net1 Is Regulated by Nuclear SequestrationOnline Journal of Public Health Informatics, 2002
- Regulation of the cytoskeleton by Rho-family GTPases: implications for tumour cell invasionSeminars in Cancer Biology, 2001
- NITRIC OXIDE AND MACROPHAGE FUNCTIONAnnual Review of Immunology, 1997