The oncogenic PI3K/Akt/mTOR pathway is frequently activated in hepatocellular carcinoma (HCC). The aim of this study is to investigate the anti-HCC effect of combination of temsirolimus, an mTOR inhibitor, and adriamycin, a routinely used drug for treating HCC.

Proliferation of HCC cells exposure to temsirolimus, adriamycin, and their combination was determined using MTT assay in vitro as well as in a nude mice model in vivo. Cell apoptosis was examined using flow cytometry. Expressions of apoptosis-related proteins including caspase-9, -3, PARP, Bax, and Bcl-2 were determined using Western blotting.

Temsirolimus plus adriamycin showed an enhanced inhibitory effect on cell proliferation compared to temsirolimus or adriamycin in HCC cells PLC/PRF/5, BEL7402, and HuH7 in vitro. The drug combination solicited a higher percentage of apoptosis cells and induced higher levels of cleaved caspase-9, -3, and PARP than temsirolimus or adriamycin used alone. The ratio of Bax/Bcl-2 was increased in cells exposed to the combination treatment. The enhanced anti-tumor effect of this drug combination was verified in a nude mice model. We also observed that half doses of temsirolimus and adriamycin used in combination achieved a comparable tumor growth inhibitor rate with full dose of temsirolimus or adriamycin used alone.

Temsirolimus plus adriamycin exhibited an enhanced antitumor effect in HCC and this drug combination might have a potential value in treatment of HCC. Studies are warranted to comprehensively evaluate the efficacy and safety of this regimen in the future.