Figure 1. Low physiologic oxygen conditions favor the expansion of choroidal melanocytes. A: Typical morphology and melanin content of choroidal melanocytes grown under 21% or 3% O₂ (P2, 1-month exposure). B: Typical morphology of uveal melanoma (UM) cells grown under 21% or 3% O₂ (P2, 1-month exposure). Scale bars, 50 µm.