Malignant growth of arsenic-transformed cells depends on activated Akt induced by reactive oxygen species

Arsenic is an identified carcinogen for humans.In this study, chronic exposure of human hepatocyte L-02 to low-doses of inorganic arsenic caused cell malignant proliferation. Meanwhile, compared with normal L-02 cells, arsenic-transformed malignant cells, L-02-As displayed more ROS and significantly higher Cyclin D1 expression as well as aerobic glycolysis. Moreover, Akt activation is followed by the upregulation of Cyclin D1 and HK2 expression in L-02-As cells, since inhibition of Akt activity by Ly294002 attenuated the colony formation in soft agar and decreased the levels of Cyclin D1 and HK2. In addition, scavenging of ROS by NAC resulted in a decreased expression of phospho-Akt, HK2 and Cyclin D1, and attenuates the ability of anchorage-independent growth ofL-02-As cells, suggested that ROS mediated the Akt activation in L-02-As cells. In summary, our results demonstrated that ROS contributes to the malignant phenotype of arsenic-transformed human hepatocyte L-02-As via the activation of Akt pathway.