Aflatoxin B1 promotes Cell Growth and Invasion in HCC HepG2 Cells through Actions on H19 and E2F1

Aflatoxins are secondary metabolites produced by the fungi, Aspergillus avus and Aspergillus parasiticus and usually divided four major types, aflatoxin B1, B2, G1 and G2. Among these, AFB1 produced by Aspergillus avus is the most potent of these toxins, and has the highest hepatocarcinogenic potential (McLean et al., 1995; IARC, 2002). The binding of AFB1 to DNA is responsible for the inhibition of RNA synthesis, which is involved in gene expression (Oyagbemi et al., 2010). It has been estimated that AFB1 can affect RASSF1A hypermethylation in hepatocellular carcinoma (Feng et al., 2012). Moreover, it has been demonstrated that AFB1 can affect the expression of a kind of genes on mRNA level, including UDP-glucuronosyltransferase (UGT) (Hanioka et al., 2012), nuclear receptors PXR, CAR, AhR and cytochromes P450 (Ayed-Boussema et al., 2012). In recent years, some author performed further study on the role of AFB1 in carcinogenesis development based on the previous study. Yang C et al found that AFB1 treatment could increase the expression of IDH3α, and the activated PI3K/Akt pathway by IDH3α eventually neutralized the apoptosis induced by AFB1 (Yang et al., 2013). Moreover, AFB1could negatively regulate Wnt/β-catenin signaling pathway through activating miR-33a (Fang et al., 2013).