To investigate if this is the case, we stained the mouse brain tissues with the astrocyte marker (GFAP; Fig. 4c), where the number of reactive astrocytes (GFAP+ cells) concentrated around GFP-HCC-515 cells was drastically higher at D5 vs. D3 post-injection (Fig. 4c; bar graph). The gene discussed is GFAP; the disease is hepatocellular carcinoma.