α-TEA cooperates with doxorubicin or cisplatin to upregulate pc-Abl and pJNK, which can serve as upstream mediators of p73. α-TEA cooperates with doxorubicin (DOXO) or cisplatin (CDDP) to upregulate pc-Abl and pJNK, which can serve as upstream mediators of p73. MDA-MB-231 and BT-20 cells were treated with DOXO or CIDDP alone or in combination with α-TEA for 24 hours. Protein levels of pc-Abl (Tyr-245), total c-Abl (tc-Abl), pJNK2/1, and total JNK2/1 (tJNK2/1) were determined by western blot (a), (b). MDA-MB-231 cells were transfected with c-Abl and JNK siRNAs, as well as control siRNA for 2 days and treated with a combination of α-TEA + DOXO or α-TEA + CDDP for 24 hours. Apoptosis was determined by annexin V/fluorescence-activated cell sorter (c). Western blot analyses were used to verify the knockdown efficiency of c-Abl and JNK siRNAs and the effect of c-Abl and JNK siRNAs on combination-induced poly(ADP-ribose) polymerase (PARP) cleavage, as well as p73 and p73-mediated death receptor 5 (DR5), Fas, Bax, Noxa and Bcl-2 (d). Data in (a), (b), and (d) representative of at least two independent experiments; data in (c) expressed as mean ± standard deviation from three independent experiments. *P <0.05, significantly different from control siRNA determined by t test. GAPDH, glyceraldehyde-3-phosphate dehydrogenase.