PROX1 and coinfection: Co-infection with lentivirus expressing RNAi-resistant Prox1 mutant (lenti-Prox1m) reinstated Prox1 expression (Fig. 1A, top, lanes 5–6), and intracellular CYP7A1 mRNA level also returned to a level comparable to HepG2 cells infected with control lentiviruses (Fig. 1A, bottom, bars 5–6).