TNFSF10 and neoplasm: Lower concentration of Birinapant (0.5 μM and 1 μM) in combination with TRAIL did not show any synergistic effect on HT29 tumour cell viability (Additional file 2: Figre S2a and S2b), but a higher concentration of Birinapant (10 μM) presented similar synergistic effect in combination with TRAIL, as with the lower concentrations 0.5–5 μM (Additional file 2: Figure S2c).