Fig. 6: EGFR signaling pathway-related electron transfer-triggered imaging in vivo during tumor treatment.

Time-dependent whole-body fluorescence images and corresponding quantitative data analysis of the tumor portion relative to the spinal symmetry region of A549 xenograft mice after intravenous injection of ETTE nanoprobe without (a, b) and with (c, d) treatment with MTH1 siRNA as a therapeutic agent for 14 days and before and after treatment. Color scale: 2.5 × 10³–1.5 × 10⁴. Data presented as mean values ± s.d., n = 3 mice. During the treatment, the afterglow images of mice treated with PBS or MTH1 siRNA were obtained at day 0 (Before treatment) and day 14 (After treatment). The afterglow imaging was performed after 1.0 s of white light excitation. The afterglow signal intensities are displayed as color maps. The white circles indicated the location of the tumor. The in vivo afterglow imaging was performed with triplicates. e A representative afterglow image of harvested tumor from the tumor-bearing mouse with ETTE nanoprobes, showing that the afterglow signal mostly appeared in large tumors. Color scale: 1.0 × 10⁴–5.0 × 10⁴. f The average tumor weight of each group at the experimental endpoint. Tumors were resected after the initial treatment. Data presented as mean values ± s.d., n = 4 mice. g Quantitative analysis of afterglow intensity in the tumor site. Data presented as mean values ± s.d., n = 4 mice. h, i IHC analysis of primary tumor sections. EGFR (h) and P-EGFR (i) in the tumor sections of each group were observed by IHC analysis. Scale bar: 50 μm. Quantitative analysis of EGFR (j) and P-EGFR (k) in tumor site observed by IHC analysis. Data are presented as the mean values ± s.d.; unpaired two-tailed Student’s t-test; n = 3 mice.