The cross-sections were stained using a macrophage marker—anti-CD68 (Cell Signaling), melanoma marker—anti-HMB45 (Abcam), melanosome marker—anti-GPNMB (R&D systems), fibroblast marker—anti-FSP1 (Abcam), pan-AKT marker (Cell Signaling) overnight at 4 °C followed by incubation in secondary antibodies Alexa Fluor 488 (Invitrogen), Alexa Fluor 594 (Cell Signaling), and Alexa Fluor 647 (Invitrogen) for 1 h at room temperature (RT). Here, PMEL is linked to melanoma.