Figure 6. Reduced expression of AK2 increases tumourigenicity in vivo and correlates with elevated FADD phosphorylation.

(a) Reconstitution with AK2 decreases tumourigenicity in vivo. C33A/Control and MCF-7/Control cells (1 × 10⁶) were injected subcutaneously into the left side of flank and C33A/AK2 and MCF-7/AK2 cells were injected into the opposite side of the same mice. After tumours had grown to the approved size, tumours were dissected and their sizes (b) and volumes were measured (c). Values are the mean±s.e.m. (n=20). *P<0.05; **P<0.005; t-test. (d) Loss of AK2 and DUSP26 expression shows the increase of p-FADD in human breast tumours. Tissue extracts were prepared from normal (N) and tumour (T) breast tissues and analysed by western blotting with anti-AK2, anti-p-FADD, anti-FADD and anti-GAPDH antibodies. (e) The AK2/DUSP26/p-FADD pathway is manifested in human breast tumours. Summary of the AK2, DUSP26 and p-FADD expression profiles. Inverse correlations between AK2 expression and p-FADD level, as well as DUSP26 expression and p-FADD level in breast specimens.