*2.2. Cell Culture*

We obtained immortalized human skin keratinocyte HaCaT and murine melanoma B16F10 cells from both Cell Line Services (CLS, Eppelheim, Germany) and American Type Culture Collection (ATCC, VA, USA). The cells were cultured in DMEM supplemented with 10% heat-activated FBS, 1% streptomycin/penicillin, and 2 mM L-glutamine in a humidified incubator supplemented with 5% CO2 at 37 ◦C.
