Effects of hyaluronan antagonism on glioma ceruloplasmin production in vivo. A, Gliomas that form after engrafting β-galactosidase-expressing C6 cells (green) stain heavily for ceruloplasmin (red). Hyaluronan oligomer treatment in vivo decreases ceruloplasmin production. B, Engraftment of C6 side population (C6SP) results in tumor formation (β-galactosidase, green) with high expression of ceruloplasmin, whereas engrafted C6 nonside population cells (C6 non-SP) do not express similar amounts of ceruloplasmin (red). Note high expression of ceruloplasmin (red) around tumor blood vessels in C6 side population tumor (see arrows). C, Gliomas that form after engrafting C6 side population cells also have high expression of ceruloplasmin (red) that is decreased with hyaluronan oligomer (5 μg). Nuclei are stained with Hoechst dye (blue).