The modified siRNAs, siKeap1-1* and siKeap1-2*, showed improved serum stability and a strongly reduced immune stimulatory potential in relation to the unmodified siRNAs (Table 2), while their potency to suppress Keap1 expression in mouse hepatoma cells remained unchanged (Fig 1A and 1B). This evidence concerns the gene KEAP1 and hepatocellular carcinoma.