The aim of the study was to investigate the anticancer effects and the molecular mechanisms of deguelin on Jurkat cells. Cell viability was assessed by MTT assay. Terminal deoxynucleotide transferase-mediated dUTP nick end labeling (TUNEL) assay and transmission electron microscopy were used to detect cell apoptosis. A propidium iodide method was used to study cell cycle distribution. RT-PCR and Western blotting were employed to assess the expression levels of steroid receptor coactivator-3 (SRC-3), nuclear factor-kappaB (NF-kappaB) and some apoptosis related genes, including Bcl-2 and Bcl-xL. Deguelin was able to inhibit cell proliferation by a cell-cycle arrest in the G(1)/G(0) phase and induce apoptosis in Jurkat cells in vitro, with a 24-h IC(50) value of 43.73 +/- 0.35 nmol/L. The antileukemia effect of deguelin might be correlated well with the downregulation of the expression of SRC-3 and its related transcription factor NF-kappaB, which thus influenced the expression of apoptosis related genes Bcl-2 and Bcl-xL. Deguelin presented potent effects on growth arrest and apoptosis induction in Jurkat cells in vitro via the interruption of SRC-3.