The document summarizes research on identifying cells that initiate human malignant melanoma (MMICs). The key findings are: 1. ABCB5, an ATP-binding cassette transporter protein, is expressed in MMICs and closely associated with advanced melanoma. 2. ABCB5+ melanoma cells were able to initiate tumor formation in mice, while ABCB5- cells did not, indicating ABCB5+ cells drive melanoma progression. 3. Blocking ABCB5 using an antibody inhibited tumor growth in mice xenografts, suggesting ABCB5 is a potential therapeutic target for treating advanced melanoma.