Figure 5

Focal adhesion kinase (FAK) is dispensable for ErbB2-induced mammary tumour initiation and progression. (a) Kinetics of mammary tumour onset in FAK^wt/wt, FAK^flox/wt, and FAK^flox/flox/mouse mammary tumour virus (MMTV)-NIC virgin female mice. The age indicated is that at which a mammary tumour is first palpable in each transgenic strain. T₅₀ denotes the age at which a tumour is palpated in 50% of the mice. *P < 0.001 vs. FAK^wt/wt mice, Student's t-test. (b) Average total tumour volume (cm³) in FAK^wt/wt (n = 11), FAK^flox/wt (n = 10) and FAK^flox/flox (n = 11)/MMTV-NIC mice. Error bars represent standard error of the mean (SEM). (c) Representative fourth inguinal mammary gland wholemounts excised from late-stage tumour-bearing animals from FAK^wt/wt (left) and FAK^flox/flox (right)/MMTV-NIC. LN indicates the lymph node. (d) H&E-stained sections from mammary glands from 4-month-old non-tumour-bearing FAK^wt/wt (left) and FAK^flox/flox (right)/MMTV-NIC animals. Images are representative of at least five animals and multiple fields were quantified. Scale bars: 200 μm. (e) Quantification of the area occupied by hyperplastic lesions expressed as a percentage (± standard error of the mean, SEM) of the total mammary gland surface (c). (f) Quantification of the epithelial content occupied per mammary gland section expressed as cells per surface (cells/mm²) (d). Error bars represent SEM. P < 0.05 vs. FAK^wt/wt mice, Student's t-test.