Background and purpose: The study has found that tumor necrosis factor-related apoptosis inducing ligand (TRAIL) can enhance the cytotoxic effect of chemotherapeutic drugs on tumor cells. The aim of our study was to investigate the effects of the tumor TRAIL and cisplatin combined application on the growth and apoptosis of human ovarian cancer cell lines SKOV3 and OVCAR3

and the possible mechanism. Methods: Under the combined application of cisplatin and TRAIL

MTT method and flow cytometry were used to detect the proliferation and apoptosis of SKOV3 of OVCAR3 cells; the mRNA expression levels of death receptors

DR4 and DR5

were detected by real-time fluorescent quantitative polymerase chain reaction (RTFQ-PCR). At the same time

the protein expression levels of DR4 and DR5 were detected by Western blot. Results: SKOV3 and OVCAR3 cells were sensitive to TRAIL protein

and with the increasing of TRAIL protein concentration

cell growth inhibitory rate up to 64%. When the combination application of TRAIL and cisplatin

the inhibition rate of the two cells reached more than 92%

and the two drugs showed high synergistic effect

compared with the single drug group (P0.05). Flowcytometry analysis indicated that the synergistic killing effect of TRAIL and cisplatin was mainly due to the cell apoptosis. RTFQ-PCR and Western blot detection results showed that the DR4 and DR5 were up-regulated under the combined application of TRAIL and cisplatin. Conclusion: In vitro

TRAIL and cisplatin combined application can significantly inhibit the proliferation of human ovarian cancer cells and induce tumor cell apoptosis. TRAIL can obviously enhance the sensitivity of cisplatin to tumor cells. The mechanism may be related to the increased death receptor DR4 and DR5 expression level.