1：Experimental Design and Method Selection:

The study involved preparing EVs from DC2.4 cells by extrusion to encapsulate doxorubicin (DOX), then incubating with HAuCl4 to self-grow gold nanoparticles around the EVs, forming a popcorn-like structure (EVdox@AuNP). This was designed to combine chemotherapy and photothermal therapy in one platform.

2：4 cells by extrusion to encapsulate doxorubicin (DOX), then incubating with HAuCl4 to self-grow gold nanoparticles around the EVs, forming a popcorn-like structure (EVdox@AuNP). This was designed to combine chemotherapy and photothermal therapy in one platform. Sample Selection and Data Sources:

2. Sample Selection and Data Sources: Used murine melanoma cell line B16F10 and DC2.4 cells, with C57BL/6 mice for in vivo studies. Data were collected from cell culture, animal models, and various analytical techniques.

3：4 cells, with C57BL/6 mice for in vivo studies. Data were collected from cell culture, animal models, and various analytical techniques. List of Experimental Equipment and Materials:

3. List of Experimental Equipment and Materials: Included HAuCl4?3H2O, MTT, DiR, DOX, DAPI, RIPA buffer, BCA kit, polycarbonate membrane filters, mini-extruder, TEM, STEM, DLS, IR thermal camera, SDS-PAGE, flow cytometer, confocal microscope, HPLC, ICP-MS, IVIS imaging system, and semiautomatic biochemical analyzer.

4：Experimental Procedures and Operational Workflow:

EVs were prepared by extruding cells with DOX, then incubated with HAuCl4 to form EVdox@AuNP. Characterization included size, morphology, stability, photothermal effects, drug release, cellular uptake, cytotoxicity assays, in vivo distribution, and therapeutic efficacy in tumor-bearing mice.

5：Data Analysis Methods:

Statistical analysis using ANOVA, with data represented as mean ± SD. Significance was set at p < 0.05.