Furthermore, previous work from our group on the effects of TNF-α on two human cutaneous melanoma cell lines, freshly isolated human ocular melanoma cells and melanocytes, has shown potent activation of transcription factor NFκB within 30 min of TNF-α stimulation (at a concentration of 200 U ml−1) and significant inhibition by α-MSH in all the cell types examined (Haycock et al, 1999). Here, TNF is linked to ocular melanoma.