Figure 3. S1P is the downstream signaling molecule of AKR1B10 playing a key role in the increase in QSG-7701 cell proliferation when co-cultured with HepG2.

(A) S1P in medium from cultured HepG2 or QSG-7701 was determined by ELISA (^#vs^*, p < 0.05). (B) QSG-7701 cells were cultured for 48 h with the regular medium (RM) or the conditional medium (CM) from HepG2 cells with addition of S1P antibody or control IgG antibody (^#vs^*, p < 0.05; ^*vs⁺, p < 0.05). (C) S1P in medium from HepG2 transfected with scramble siRNA (Scr) or AKR1B10 siRNA (AKR1B10) and cultured for 48 hours was determined by ELISA (^#vs^*, p < 0.05).