Quantitation of metastatic growth over all serial sections of the lungs showed a significantly decreased tumor burden in both area (Fig. 5c; raw tumor area data shown in Supplementary Figure S8a) and percentage tumor (Supplementary Figure S8b) in mice injected with a population with either reduced MITF or BRN2 (P < 0.0001, Mann-Whitney test). The gene discussed is POU3F2; the disease is neoplasm.