Fig. 6: The combined administration of YD and gefitinib can delay the emergence of resistance and inhibit AXL overexpression in a long-term in vivo xenograft model.

HCC827-Luc cells were subcutaneously implanted into the flanks of Balb/c-nude mice (five mice per group). Drugs were orally administered 6 times per week for 90 days and doses indicated are 0.5 mg/kg for YD, 10 mg/kg for gefitinib (a). The graph represents tumor volumes of indicated days which were normalized to the initial tumor volume for comparison (b). Bioluminescence images of mice at the final day before sacrifice were measured and mice were injected with Firefly D-luciferin before imaging (c). Immunohistochemical analysis of AXL was performed in tumor tissue (d). The schematic diagram illustrating the significance of combined YD with EGFR-TKI treatment in NSCLC (e). *P < 0.05, **P < 0.01, ***P < 0.005 by t-test