PXN and coinfection: These results suggest that co-infection with a low-risk HPV6 E6 + EBV LMP-1 (6E6 + LMP-1) is incapable of causing invasion and anchorage-independent growth because such an expression would not affect adhesion signaling by MMP-2, paxillin, and Cat-1 in the same way that high-risk HPV16 E6 and EBV LMP-1 co-expression does.