HTR2B and neoplasm: In five out of eight primary tumor samples, we identified one or more clusters of hybrid cells (Fig. 2B and Supplemental Files 2–5) based on co-expression of tumor genes MITF, MLANA, DCT, TYR, GP100, and HTR2B, and macrophage genes CD45, CD14, CD163 (Fig. 2C-E for patient UMM059.