KRAS and hepatocellular carcinoma: Moreover, liver cell proliferation in the kras/L-ARKO zebrafish after the co-treatment of androgen and Dox showed no significant change, in contrast to the dramatic stimulation of liver cell proliferation in the androgen/Dox co-treated kras zebrafish, further demonstrating that the liver-specific ar knockout blocked the effects of androgen treatment on cell proliferation during HCC progression.