Apoptosis assay by Annexin V-FITC/PI double staining followed by microscopy and flow cytometry showed that while Dox induced-TRAIL expression was detected by both RT-PCR and Western blot assay in U251 and MDA-MB-231 cells (Figure 3A), tumor cell death by apoptosis was occurred markedly (Figure 3B). The gene discussed is TNFSF10; the disease is neoplasm.