Anti trp2

Total protein was isolated from exosomes or PIG1 cells using RIPA plus PMSF (Beyotime, China). The protein concentration was detected by the BCA Kit (Beyotime, China). The protein samples were separated by SDS-PAGE gel electrophoresis, and then transferred to PVDF membranes. After blocking, the membranes were incubated with the specific primary antibodies anti-CD63 (cat: ab193349, 1:1000, Abcam, USA); anti-TSG101 (cat: #72312, 1:1000, CST, USA); anti-MITF (cat: #12590, 1:1000, CST, USA); anti-Tyrosinase (cat: ab170905, 1:1000, Abcam, USA); anti-TRP1 (cat: ab235447, 1:1000, Abcam, USA); anti-TRP2 (cat: ab234901, 1:1000, Abcam, USA); anti-SATB1 (cat: ab109122, 1:1000, Abcam, USA); anti-GAPDH (cat: #5174, 1:2000, CST, USA) at 4°C overnight. The horseradish peroxidase-labeled secondary antibody (1:1000, Abcam, USA) was incubated for 2 h at room temperature. The ECL kit (Beyotime, China) was used to visualize the membrane. The proteins were analyzed with Image J software.

Tumors were harvested at 0, 3, 6, 12 and 24 hours after treatments. Tumor tissue was wrapped with Nylon filter paper with a pore size of 15 µm and centrifuged at 2500 rpm in a 15 mL centrifuge tube for 20 min. Tumor interstitial fluid was collected. 50 µg of total proteins were separated onto a 4%–20% gradient Tris-Glycine precast gel and transferred to a PVDF membrane. Blot was probed with anti-TRP2 (Abcam). Each shown Western blot was a representative from three separate experiments.