Fig. 3

Decreased drainage of nanoparticles from tumor to draining LNs, and enhanced intratumoral accumulation of nanoparticles or free Dox after lymphangiogenesis inhibition. a Representative multiphoton laser scanning microscopy images of the drainage of tumor-associated LVs for Lip-Rhodamine. Scale bar, 100 μm in the right and left panels and 50 μm in the middle panels. b Ex vivo fluorescence images of tumors and draining LNs 8 h after intratumoral injection of Lip-Cy5.5 in 4T1 tumor-bearing mice. c, d Quantitative analysis of the fluorescence intensities in the tumors (c) and draining LNs (d) 8 h post-injection (n = 3). e, f After treatment with saline, anlotinib or SAR131675, the mice were intratumorally administered with 100 nm AuNPs. Representative TEM images of inguinal LNs are shown (e), and the number of AuNPs per field was quantified (f) (n = 5). Scale bar, 1 μm. The upper panels show enlarged images of the indicated areas of interest. Scale bar, 100 nm. g–j Anlotinib treatment enhanced the intratumoral accumulation of nanoparticles. After treatment with saline or anlotinib, the mice were intravenously administered 40 nm fluorescent microspheres. Representative in vivo fluorescence images at different time points are shown (g). Tumors were circled with black lines, and their average fluorescence intensities were quantified (h) (n = 4). Tumors were excised 24 h post-administration for ex vivo imaging (i), and the average fluorescence intensity was quantified (j) (n = 4). k, l Anlotinib treatment enhanced intratumoral accumulation of free Dox. 4T1 tumor-bearing mice treated with saline or anlotinib were intravenously administered Dox. The content of Dox in tumor tissue was measured by HPLC 12 h and 24 h post-injection (k) (n = 4). Fluorescent images of Dox in tumor sections 24 h post-injection are shown (l). Scale bar, 100 μm. m, n SAR131675 treatment enhanced intratumoral accumulation of nanoparticles. 4T1 tumor-bearing mice treated with saline or SAR131675 were intravenously administered Lip-Cy5.5. Tumors were excised 8 h post-administration for ex vivo imaging (m), and the average fluorescence intensity was quantified (n) (n = 3). o SAR131675 treatment enhanced intratumoral accumulation of free Dox. 4T1 tumor-bearing mice treated with saline or SAR131675 were intravenously adminisered Dox. The content of Dox in tumor tissue was measured by HPLC 12 h post-injection (n = 3). The data are presented as the mean ± s.d. *p < 0.05; **p < 0.01; ***p < 0.001