Figure 2

Valproic acid combined with temsirolimus induced Burkitt leukemia/lymphoma (BL) cell autophagy. (A) As detected by flow cytometry, co-treatment of valproic acid (VPA, 0.5 mM) with temsirolimus (TEM, 1nM) increased LC3 intensity in BL cell lines Namalwa, Raji, Daudi and Ramos. (B) Western blot analysis revealed that combined treatment increased BECN1 expression, but decreased expression of P62, p-MTOR, p-4EBP1, p-P70S6K and MYC. (C) Ultrastructural study of Namalwa and Raji cells showed that combined treatment induces more frequently BL cell autophagy than each agent alone. (D-F) Growth inhibition of Namalwa cells was significantly reduced by autophagy inhibitor 3-Methyladenine (0.5 mM) and Bafilomycin A1 (10 nM) (D), **P<0.01, *P<0.05 comparing with no inhibitor), by molecular silencing of the ATG5 siRNA (E, *P<0.05 comparing with CON siRNA), but not by pan-caspase inhibitor ZVAD-FMK (0.3 mM) (F).