Activation of Src and p120 phosphorylation correlates with increased glioma invasiveness.
A. Seventeen glioma cell lines propagated as xenografts in mouse flank were examined by western blot for expression of active (Y416-phosphorylated) and total Src and Y228-phosphorylated and total p120 catenin proteins. Actin is a loading control. The positive control lysate is from MDA231 cells. Xenograft lines were previously classified based on their relative invasiveness as highly or moderately invasive (data boxed in gray) or minimally or non-invasive (not boxed). B. The level of Y228-phosphorylated p120 catenin expression (relative to actin expression) as determined by Western blot for each cell line was plotted vs. relative glioma invasiveness. The lines through the data indicate the median for each invasiveness category; n = 8 highly/moderately invasive lines and n = 9 minimally/non-invasive lines; **indicates a statistical difference (one-tailed, unpaired t test) between the two categories of invasiveness at p<0.005. C. Human prostate tumor, breast tumor, astrocytoma, and GBM samples were examined by immunohistochemistry for total p120 catenin expression (using the 15D2 antibody), and Y228-phosphorylated p120 catenin expression. Bar: 100 µm.