Type I interferon and TNFalpha cooperate with type II interferon for TRAIL induction and triggering of apoptosis in SK-N-MC EWING tumor cells.

Ewing's sarcoma is the second most common human bone tumor in childhood. Here, we investigated the sensitivity of the Ewing tumor cell line, SK-N-MC, to the apoptotic effect of type I (IFNalpha) and type II (IFNgamma) interferons and TNFalpha. We demonstrate that although IFNalpha and TNFalpha alone are unable to induce cell death, they act in synergy with IFNgamma to induce SK-N-MC cell apoptosis.

Involvement of TNF-related apoptosis-inducing ligand (TRAIL) induction in interferon gamma-mediated apoptosis in Ewing tumor cells.

We investigated the effect of IFN gamma or IFN gamma/IFN alpha and IFN gamma/TNF treatment on the apoptosis of Ewing tumor cells (SK-N-MC). The results show that treatment of cells with IFN gamma resulted in 17% of cell death while no effect was observed when cells were treated with IFN alpha or TNF alone. Percentage cell death increased markedly in IFN gamma/IFN alpha- and IFN gamma/TNF-treated cells (42% and 67%, respectively) as compared to IFN gamma-treated cells.