Depletion of Id2 leads to up-regulation of E-cadherin and anchorage-independent growth in uveal melanoma cells. A, anchorage-independent colony formation of Mel202 melanoma cells in soft agar, measured as the number of colonies per ×20 field following transfection with an Id2 antisense vector or an empty control vector. DECMA1 indicates that soft agar was incubated with neutralizing anti-E-cadherin antibodies. Columns, mean of triplicate experiments; bars, SE. B, representative bright-field photomicrographs from soft agar assays, showing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide–stained viable tumor cells. Large multicellular spheroids were seen only in cells transfected with the Id2 antisense vector (middle). Bars, 150 μm.