Protein expression profiles in the epidermis of cyclooxygenase-2 transgenic mice by 2-dimensional gel electrophoresis and mass spectrometry.
Exposure of murine skin to tumor-promoting agents such as 12-O-tetradecanoyl-phorbol-13-acetate (TPA) causes up-regulation of cyclooxygenase-2 (COX-2) and increased prostaglandin (PG) synthesis. Pharmacological inhibition of COX-2 significantly reduces skin tumor development. However, we previously demonstrated that K14.COX-2 transgenic (TG) mice that overexpressed COX-2 in the epidermis were unexpectedly resistant to tumor development under the classical 7,12-dimethylbenz[a]anthracene-TPA protocol. In the present study, we employed a proteomic approach of 2-dimensional gel electrophoresis (2-DE) and mass spectrometry to profile differentially expressed proteins in the epidermis of K14.COX-2 TG and wild-type control mice. Various 2-DE approaches were used to identify the maximum number of differentially expressed proteins: 20 for untreated samples, 3 for acetone-treated samples, and 22 for TPA-treated samples. These proteins include 14-3-3 sigma, numerous actin fragments, actin filament related proteins cofilin-1 and destrin, galectin-3, galectin-7, prohibitin, S100A6, S100A9, and many others. The differential expression of galectin-3, galectin-7, S100A9 was validated by Western blot analysis and/or immunohistochemical analysis. The current data suggest that some of the differentially expressed proteins might increase apoptosis and cell cycle arrest, which, in turn, may provide insight into the role of COX-2 in skin tumorigenesis.
Shen
Jianjun
J
The University of Texas M. D. Anderson Cancer Center, Science Park-Research Division, Smithville, Texas 78957, USA.
Pavone
Amy
A
Mikulec
Carol
C
Hensley
Sean C
SC
Traner
Angelina
A
Chang
Thom K
TK
Person
Maria D
MD
Fischer
Susan M
SM
D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis; D002135:Calcium-Binding Proteins / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000096:biosynthesis*; D015180:Electrophoresis, Gel, Two-Dimensional; D004817:Epidermis / Q000201:enzymology* / Q000378:metabolism; D013058:Mass Spectrometry / Q000379:methods*; D051379:Mice; D008822:Mice, Transgenic; D008954:Models, Biological; D008969:Molecular Sequence Data; D040901:Proteomics / Q000379:methods; D012867:Skin / Q000187:drug effects*; D015854:Up-Regulation
D002135:Calcium-Binding Proteins; D051546:Cyclooxygenase 2