Figure 5. Apln-CreER labels active angiogenesis in orthotopic and spontaneous tumour models.

(a) Strategy of orthotopic tumour model establishment and tamoxifen treatment strategy. (b) Whole mount view of liver orthotopic tumours based on Apln-CreER;Rosa26-Reporter mice. Black arrows indicate tumours. The grey arrows and boxed areas in the middle panels are magnified below. (c) Immunostaining of RFP, PECAM and DAPI (4',6-diamidino-2-phenylindole) on tumour and healthy tissue sections. (d) Quantification of RFP⁺ vessels. Student’s t-test was used to analyse differences and values are shown as means±s.e.m.; *P<0.05; n=4. (e) Strategy of in situ tumorigenesis by DEN treatment. DEN was injected at P0.5m (postnatal half month) and tamoxifen was administered at P7.5m and P8m, and tumours were collected at P8.5m. (f) Whole mount view of DEN-induced liver tumour model. The tumour (black arrowheads) is enriched for Apln⁺ vessels (RFP⁺). Representative of at least five individual mice. (g) Immunostaining of RFP, PECAM and DAPI on sections of DEN-induced tumour sample. Student’s t-test was used to analyse differencesand values are shown as means±s.e.m.; *P<0.05; n=5. (h,i) Tumour and healthy tissue from the liver or colon of the same patient were collected (n=16 for liver and n=12 for colon). Apln mRNA expression was measured by quantitative reverse transcription PCR and normalized to β-Actin mRNA. Relative Apln expression in non-tumour tissue surrounding tumour sample was assigned a value of 1. Expr., expression. Scale bars, 1 mm.