Karyomegaly and kCYC mRNA positivity in nuclei of cells lining dilated vascular structures that express podoplanin and VEGFR-3 in kCYC^+/- transgenic mice. (A) H and E staining of TG lung (left) and tagged TG ear skin (right) showing karyomegaly of endothelial cells (arrows). These cells were never observed in tissue obtained from WT mice (data not shown) (× 100-200). (B) Karyomegaly of endothelial cells (arrows and blue DAPI stain) lining vascular structures in tagged TG ear skin that contain erythrocytes and express podoplanin (red) and VEGFR-3 (green) (× 200). (C) In situ hybridizations for kCYC mRNA in tagged TG ear skin of 2 different mice both showing positive antisense signals in karyomegalic cells that line dilated vascular structures and contain erythrocytes. Dark field (i) and bright field (ii) from a single mouse processed with ³⁵S-radiolabeled antisense probes for 7 days. Lower panels show serial sections of tissue from a second mouse processed with ³⁵S-radiolabeled antisense (AS, left) or sense (S, right) control probes. Signals above background were never observed in tissues obtained from WT mice (data not shown) (× 200).