Methoxymorpholinyl doxorubicin (PNU 152243) is a morpholinyl analog possessing a methoxymorpholinyl group at the 3' position of the sugar moiety, which, compared with doxorubicin, appears to be less cardiotoxic and more cytotoxic against multidrug-resistant tumor cells. In this study, we report the anticancer activity of PNU 152243 on human hepatocellular carcinoma (HCC) in vitro and in vivo. The average IC50 value of PNU was 0.08 microM. In contrast, the average IC50 values of adriamycin (ADM), 4'-epidoxorubicin (EDR), mitomycin C (MMC), cisplatin and vepesid (VP-16) were 0.96, 0.74, 2.81, 7.27 and 26.66 microM, respectively. PNU 152243 was 13.7, 10.6, 40.1, 103.8 and 380.8 times more potent than ADM, EDR, MMC, cisplatin and VP-16 against HCC in vitro. In nude mice, the T/C (%) were 43.8 at the dose of 25 microg/kg and 41.2 at the dose of 50 microg/kg on BEL-7402 xenograft, the T/C (%) were 41.7 at the dose of 25 microg/kg and 54.6 at the dose of 50 microg/kg on Zip-177 xenograft. The results showed that PNU 152243 had growth inhibition of HCC in vitro and in vivo and may be useful in HCC chemotherapy.