All drugs and biochemicals were purchased from Sigma-Aldrich Fine Chemical Co, St Louis, Missouri, unless otherwise specified. Tissue culture reagents were purchased from Invitrogen Corporation/Gibco Life Sciences, Carlsbad, California. The UM-SCC-1 cell line was generously provided by Thomas Carey, PhD, University of Michigan, Ann Arbor); the UPCI:SCC116 cell line (referred to in this article as SCC116) by Susanne Gollin, PhD, University of Pittsburgh, Pittsburgh, Pennsylvania; and the DM12 cell line by Jeffrey Meyers, MD, PhD, MD Andersen Cancer Center, Houston, Texas. The Chinese hamster ovary cells were purchased from American Type Culture Collection, Manassas, Virginia. Cells were grown as monolayer cultures in Dulbecco Modified Eagle Medium supplemented with 10% fetal bovine serum, 1% penicillin-streptomycin, 1% L-glutamine, and 1% nonessential amino acids. Adenoviral VEGF-C RNAi construct, AdshRNA-VEGFC, was produced in conjunction with Beverly Davidson, PhD, in the Gene Transfer Vector Core at the University of Iowa, Iowa City.