Figure 4. HDAC and mTORC1 inhibition attenuate cap-independent translation but not inhibit cap-dependent translation in Myc-CaP cell lines and tumors.

(A) Western blot analysis of p-S6K, total S6K, p-4EBP1 and total 4EBP1 proteins. MycCaP cells were treated with 10 nM everolimus, 10 nM panobinostat or combination for 24 hours. Cell lysates were then subjected to immunoblot and incubated with the respective antibodies. β-actin served as loading control. (B) Myc-CaP/AS tumors or (C) Myc-CaP/CR tumors (∼5 mm²) were transplanted into the flank of wild type FVB intact male mice. Approximately ten (10) days post transplantation mice were treated daily with 10 mg/kg everolimus orally, 10 mg/kg panobinostat IP or both agents concurrently for a total of 15 days. Excised tumors were formalin-fixed paraffin and stained for the downstream targets of mTORC1 signaling, p-S6K and p-4EBP1. Magnification (×40); Scale bar = 50 µM.