Figure 1
Wnt5a protein levels are reduced in DNIIR tumours. (a) Repeated measures modelling of tumour volume over time in the MMTV-neu model shows statistically significant differences at 63 days in mean tumour volume between control and DNIIR groups (P < 0.01; control = 2.57 cm3 ± 0.53 cm3, n = 12; DNIIR = 4.21 cm3 ± 0.17 cm3, n = 33). (b) In the MMTV-PyVmT model, a graphical plot of mean tumour volumes at the time of sacrifice reveals significantly larger tumours in the DNIIR group versus controls (P < 0.0001; control = 20 mm3, n = 8; DNIIR = 65 mm3, n = 8). (c) Ki67 staining in the MMTVneu model shows increased levels of proliferation in the DNIIR primary tumours compared with controls (P < 0.0001; six tumours per group, five fields per tumour were counted). (d) BrdU incorporation in tumours of the MMTV-PyVmT study illustrates increased proliferation in DNIIR tumours (P < 0.0001; eight tumours per group, three fields per tumour). (e, f) Vascular density, measured by CD31 pixel density, was greater in DNIIR groups within both (e) MMTV-neu and (f) MMTV-PyVmT studies (MMTV-neu = P <0.02, five tumours per group, three fields per tumour; MMTV-PyVmT = P < 0.01, four tumours per group, three fields per tumour). (g, h) Western blotting for Wnt5a protein in lysates from several separate (g) MMTV-neu and (h) MMTV-PyVmT tumours with or without DNIIR, indicating a decrease in overall levels of Wnt5a protein in primary tumours with alterations in TGF-β signalling. β-Tubulin is used as a loading control. DNIIR = dominant-negative TGF-β type II receptor; MMTV = mouse mammary tumour virus promoter/enhancer; PyVmT = polyoma virus middle T antigen; TGF-β = τransforming growth factor-beta; Wnt = Wingless-related protein family.