OCM and uveal melanoma: Basal pIκBα was observed significantly in the four untreated uveal melanoma cell lines, SP 6.5, VUP, OCM1 and OM431, while the retinal pigment epithelium (RPE) cell line ARPE-19 showed weakly activation, which meant the constitutive expression and activation of NF-κB in the uveal melanoma cells (Figure 1A).