Table 2 Interactions between HPV oncoproteins and β-catenin in Wnt signaling

E6

E6-E6AP-β-catenin

Blocks proteasomal degradation of β-catenin and promotes its translocation to the nucleus

E6-Dlg2/Scribble-APC-β-catenin

Inactivates APC and leads to β-catenin nuclear accumulation through E6-induced degradation of the Dlg1 and Scribble

E6-MZF1/NKX2-1/FOXM1-β-catenin

Induces MZF1 expression and then activates NKX2-1 transcription, finally promotes FOXM1- mediated β-catenin nuclear translocation

E6-p53-Siah-1/SIP/Ebi-β-catenin

E6-induced loss of p53 inactivates Siah-1/SIP/Ebi complex, which can act as β-TrCP and lead to β-catenin degradation

E7

E7-PP2A-β-catenin

Binds to both the catalytic and structural subunits of PP2A and consequently induces Wnt activation