Western blot analysis of RAB27A was performed by loading 20 µg of SK-MEL-28 and SH-SY5Y whole cell lysates and 5 µL of PageRuler Plus Prestained Protein Ladder (Product # 26619) per well onto a Novex 4-20% Tris-Glycine polyacrylamide gel (Product # WT4202BOX ). Proteins were transferred to a nitrocellulose membrane using the G2 Blotter (Product # 62288), and blocked with 5% Milk in TBST for 1 hour at room temperature. RAB27A was detected at ~25 kDa using a RAB27A monoclonal antibody (Product # MA1-172) at a dilution of 1 µg/mL in 5% Milk in TBST overnight at 4°C on a rocking platform, followed by a Goat anti-Mouse IgG (H+L) Superclonal Secondary Antibody, HRP conjugate (Product # A28177) at a dilution of 1:1,000 for at least 30 minutes at room temperature. Chemiluminescent detection was performed using SuperSignal Pico substrate (Product # 34078) and the myECL Imager (Product # 62236).