Fig. 1

Wtp53 and high-dose delivery contribute to the Abscopal effect in in vivo NSCLC tumor models. a Experimental design of in vivo experiments aimed at evaluating the tumor-growth of irradiated (IR) and non-irradiated contralateral (NIR) tumors; control (UnIR) non-irradiated mice are also shown. b WTp53 A549 xenografts and (c) p53-null H1299 xenografts. Wtp53-depleted (sh/p53) (d) and control (sh/scr) (e) A549 xenograft tumor growth after RT are reported. Volumetric data were obtained using 8 mice/group and were normalized to the initial volume of tumor-bearing mice at the time of radiation (V0). Data represent the mean (± standard deviation, SD) of two independent experiments. (* p < 0.05; **p < 0.01). f Representative images of the abscopal effect in mice bearing functional p53 (A549 sh/scr). The mice bearing silenced p53 (A549 sh/p53) showed, as expected, tumor growth in the NIR contralateral mass. All the animals were xenografted subcutaneously on both flanks. Black arrows show tumors directly irradiated (20 Gy). g Immunohistochemical staining for F4/80 in mouse A549 xenograft tissue section. Images are representative of control (UnIR), 20 Gy-irradiated (IR) and contralateral non-irradiated (NIR) tumor masses infiltrated by F4/80-positive macrophages (arrow). The number of positive cells in 6 random field profiles was used for statistical analysis. h Lipofuscin staining of A549 xenograft tissue section to detect senescence cells. To quantify lipofuscin positive cells, a homemade Matlab tool was used. The appropriated mask needed to identify the lipofuscin positive cells in the investigated area was obtained using the function imageSegmenter as detailed in supplementary notes. (*** p < 0.0001) (i) IL6 expression through digital qRT-PCR analysis of RNA extracted from A549 xenograft tissue sections. j Different expression levels of IL6 in serum collected from A549 xenograft nude mice irradiated (IR) or not (UnIR) at 20 Gy. (* p < 0.05; ***p < 0.001)