Figure 1. Highly metastatic LNM35 tumors are highly angiogenic and lymphangiogenic and rich in macrophages.
(A) Comparison of tumor growth rates between N15 and LNM35 cells inoculated subcutaneously at day 0. Tumor growth rates were significantly different (**p<0.01, n = 6). (B) IHC analysis using antibodies against vascular endothelium (CD31) and lymphatic vessels (LYVE-1), a macrophage-specific antibody (F4/80), and a neutrophil-specific antibody (Gr-1). N15 and LNM35 tumors were quantitatively analyzed, scoring five areas in each tumor section for microvascular density (MVD), lymphatic vessel density (LVD), F4/80-positive cells, and Gr-1-positive cells; *p<0.05 and ** p<0.01. (C) Comparison of lymph node weights between N15 and LNM35 tumors on day 35 after subcutaneous inoculation (**p<0.01, n = 6). (D) H&E staining of lymph node samples from mice subcutaneously injected with N15 and LNM35 cells (n = 2 each); T: tumor, LN: lymph node. (E) Comparison of tumor growth rates following the subcutaneous inoculation of N15 and LNM35 cells at day 0. N15 tumors at day 38 and LNM35 tumors at day19 were of similar size and were further analyzed. (F) IHC analysis using antibodies against vascular endothelium (CD31), lymphatic vessels (LYVE-1), macrophages (F4/80), and neutrophils (Gr-1). Five N15 and LNM35 tumors were quantitatively analyzed, scoring five areas in each tumor section for MVD, LVD, F4/80-positive cells, and Gr-1-positive cells. ** p<0.01.