The synergistic anti-tumor effect of M3814 and etoposide in NSCLC xenografts. NOD-SCID mice implanted with A549 and H460 tumor xenografts were treated with M3814 (50 mg/kg, i.g. daily) and etoposide (10 mg/kg, i.p. once 3 days). (A) Subcutaneous A549 and H460 tumors at the end of this experiment. (B) and (C) Growth of A549 and H460 xenografts presented as mean RTV (relative tumor volume). Error bars denote SD. (D) and (E) The final RTV of xenograft tumors measured in each group. Data are presented as mean ± SD (n = 7, ∗∗∗∗P < 0.0001, ∗∗∗P < 0.001, ∗P < 0.05; ns, P > 0.05). (F) Representative images of immunohistochemistry staining of Ki67, γ-H2AX, pDNA-PKcs and immunofluorescence staining of TUNEL evaluated on paraffin-embedded A549 tumor sections, scale bar = 50 μm (magnification, 200 ×). Representative images of SA-βGal staining of frozen sections of A549 tumors, scale bar = 50 μm (magnification, 200 ×).