FAS and melanoma: Erb et al. (2005) provoked a controversy with the role of FAS and/or FASL in human malignant melanoma. Therefore, the effect of FAS and/or FASL on cell viability was evaluated by Kim et al. (2012) by adding Fas/FasL antagonist Kp 7–6 of concentration 1 mM and incubated it for 1 h.