Figure 6: LRP6 ectodomain prevents non-canonical pathway-regulated metastasis of mouse breast tumour in vivo.

(a,b) WB analysis of p-c-jun and cell migration in cultured 4T1 cells. LRP6N attenuated c-jun activity (a) (n=3) and cell migration (b) at the basal level. Values represent mean±s.d. of three experiments. (c) Micro-CT images of the lungs were obtained from mice injected with LRP6N- or GFP-overexpressing 4T1 cells on day 25 and day 35. The multifocal tumour progression is clearly depicted from day 25 to day 35 in GFP-overexpressing mouse-1 and between LRP6N- and GFP-overexpressing mice at day 35. Axial slice orientation in corresponding positions. Segmentation of aerated lung (blue) was used as a surrogate parameter to assess the multifocal tumour spread (lower panels). The rate of aerated lung/thoracic cavity was higher in tumours from LRP6N-overexpressing 4T1 cells (∼48.53%) than GFP-overexpressing cells (∼22.77%), indicating less metastases in LRP6N-treated tumours. P=primary tumour; M=metastases; L=lung; H=heart. (d) Histology at day 35 showed distinctive tumour burden in corresponding areas by H&E staining. Arrow showed metastatic tumours. T=tumour cells; A=lung alveolar cells. Much more alveolar cells were present in LRP6N-overexpressing 4T1 cells than GFP-overexpressing cells (lower panel. blue colour and bar graph), indicating less metastases in LRP6N-treated tumours. Scale bar, 2 mm.