Expression of VHL and Ras proteins in canine hemangiosarcoma cell lines. DD-1, Dal-4, and Frog canine hemangiosarcoma cell lines were cultured in chamber slides and stained with an irrelevant control antibody, or with antibodies against VHL or pan-Ras as indicated on the left. Cells were visualized using bright field microscopy at low magnification (10× objective, BF 10×) and staining in the same fields was visualized using epifluorescence (FL 10×). Bars = 200 μm. Right panels show photomicrographs of DD-1 cells under bright field illumination at high magnification (40 × objective, BF 40×) to illustrate the localization of VHL to the cytoplasm and the localization of Ras predominantly to the inner plasma membrane (red staining). Bars = 20 μm.