After tail vein injection, MDA-MB-231EP300KD cells expressing GFP/luciferase showed no tumor formation in the lungs or other parts of the mouse body in vivo compared to large tumor masses (as determined by fluorescence signal intensity) in the control (scramble) group (RLU × 105: scramble 2.6 ± 3.19, EP300 KD clone 1 0.006 ± 0.004, EP300 KD clone 2 0.004 ± 0.003) (Fig. 4b and c) (MDA-MB-231EP300KD clone 1 vs. scramble p = 0.005, clone 2 vs. scramble p > 0.0001). This evidence concerns the gene EP300 and neoplasm.