Analysis of tumor microenvironment in A20 B lymphoma–engrafted mice. (A) Cytokine expression levels in tumor tissues from mice injected intravenously with pA20-36 or pCNT peptides (200 mg ≃ kg−1 ≃ d−1) at day 24 after treatment. Mean values ± SDs of 3 independent experiments are shown. Statistical analysis was performed according to the Student t test (n = 4 tumors per group). (B) Inhibition of tumor angiogenesis by the pA20-36 peptide. Sections of fresh tumor tissues were incubated with antibody to CD31 to stain endothelial cells, together with TOPO-3 staining followed by confocal microscopy. Panels are representative of samples from 4 mice per group with similar staining profiles. Pictures were captured with a Leica TCS SP2 confocal microscope with a HC PL FLUOTAR 20×/0.50 oil UV objective (NA 0.50) in glycerol and acquired with Leica Confocal Software Version 2.61. Image manipulation was performed with Adobe Photoshop CS. (C) Quantitative analysis of vessel density. The mean number of vessels per field (56.25 μm2) of tumor sections described in panel B is shown; mean values ± SDs (n = 4/group); statistical analysis was performed according to the Student t test.
