To test the role of the ATM or ATR pathway in HBV CCC DNA formation, we tested the effects of specific inhibitors of these pathways on HBV CCC DNA formation in human hepatoma HepG2 cells reconstituted with the HBV receptor NTCP, in which HBV CCC DNA can be formed early during de novo infection from the incoming virion RC DNA (32). Here, ATR is linked to infection.