Browse by author
Lookup NU author(s): Professor Bruce Westley, Dr Felicity May
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
We have investigated the possible functional relationships between cellular invasion pathways induced by trefoil factors (TFFs), src, and the cyclooxygenases COX-1 and COX-2. Pharmacological inhibitors of the Rho small GTPase (C3 exoenzyme), phospholipase C (U-73122), cyclooxygenases (SC-560, NS-398), and the thromboxane A2 receptor (TXA2-R) antagonist SQ-295 completely abolished invasion induced by intestinal trefoil factor, pS2, and src in kidney and colonic epithelial cells MDCKts.src and PCmsrc. In contrast, invasion was induced by the TXA2-R mimetic U-46619, constitutively activated forms of the heterotrimeric G-proteins G alphaq (AG alphaq), G alpha 12, G alpha 13 (AG alpha 12/13), which are signaling elements downstream of TXA2-R. Ectopic overexpression of pS2 cDNA and protein in MDCKts.src-pS2 cells and human colorectal cancer cells HCT8/S11-pS2 initiate distinct invasion signals that are Rho independent and COX and TXA2-R dependent. We detected a marked induction of COX-2 protein and accumulation of the stable PGH2/TXA2 metabolite TXB2 in the conditioned medium from cells transformed by src. This led to activation of the TXA2R-dependent invasion pathway, which is monitored via a Rho- and G alpha 12/G alpha 13-independent mechanism using the G alphaq/PKC signaling cascade. These findings identify a new intracrine/paracrine loop that can be monitored by TFFs and src in inflammatory diseases and progression of colorectal cancers.
Author(s): Rodrigues S, Nguyen QD, Faivre S, Bruyneel E, Thim L, Westley B, May F, Flatau G, Mareel M, Gespach C, Emami S
Publication type: Article
Publication status: Published
Journal: The FASEB Journal
Year: 2001
Volume: 15
Issue: 9
Pages: 1517-1528
ISSN (print): 0892-6638
ISSN (electronic): 1530-6860
Publisher: Federation of American Societies for Experimental Biology
URL: http://dx.doi.org/10.1096/fj.00-0802com
DOI: 10.1096/fj.00-0802com
Altmetrics provided by Altmetric