Figure 8. Combination treatments of afatinib and gemcitabine in nude mice.

(A) Effects of afatinib, gemcitabine, or in combination on the tumor growth of PC-9 cells in xenograft mice. After the subcutaneous inoculation of PC-9 cells for 14 days, the nude mice were randomly assigned into four groups for treatment: afatinib group (n = 10), gemcitabine group (n = 10), afatinib/gemcitabine group (n = 10), and control group (n = 10). For the treatment, afatinib in sterile water was orally taken with 10 mg/kg daily, and gemcitabine in PBS was orally administrated with 100 mg/kg weekly. Mouse body weights and tumor sizes in appearance were measured and recorded every 3 days. (B) Tumors on xenograft mice. After 15-day treatment, the mice in the four groups were aligned to show the tumors on the mouse skin and imaged. (C) Tumor lesions and tumor masses. Fifteen days after the treatment, the mice were sacrificed and the tumor lesions were taken out, weighed and photographed. The mouse numbers for each group were 10 (n = 10) and one tumor lesion was vanishing after the afatinib treatment in the group. (D) Immunofluorescent analysis of RRM2 in the tumor lesions after afatinib treatment using an anti-RRM2 antibody. Nuclei were counterstained with DAPI. Red, RRM2; Blue, nuclei. Amplification, 100X. The tumor masses were statistically calculated and plotted. (^*p < 0.05, ^**p < 0.01, and ^***p < 0.001).