WNT7A and neoplasm: Next, to assess the effect of manipulating tumour cell Wnt7a expression levels on the fibroblast compartment in vivo, CAF recruitment was assessed in tumours generated by orthotopic inoculation of 4T07 cells ectopically expressing Wnt7a (4T07-Wnt7a; Fig. 3a and Supplementary Fig. 3a).