ABSTRACT
Purpose: Alteration in cell death is a hallmark of cancer. A functional role regulating survival, apoptosis, and necroptosis has been attributed to RIP1/3 complexes.Experimental Design: We have investigated the role of RIP1 and the effects of MC2494 in cell death induction, using different methods as flow cytometry, transcriptome analysis, immunoprecipitation, enzymatic assays, transfections, mutagenesis, and in vivo studies with different mice models.Results: Here, we show that RIP1 is highly expressed in cancer, and we define a novel RIP1/3-SIRT1/2-HAT1/4 complex. Mass spectrometry identified five acetylations in the kinase and death domain of RIP1. The novel characterized pan-SIRT inhibitor, MC2494, increases RIP1 acetylation at two additional sites in the death domain. Mutagenesis of the acetylated lysine decreases RIP1-dependent cell death, suggesting a role for acetylation of the RIP1 complex in cell death modulation. Accordingly, MC2494 displays tumor-selective potential in vitro, in leukemic blasts ex vivo, and in vivo in both xenograft and allograft cancer models. Mechanistically, MC2494 induces bona fide tumor-restricted acetylated RIP1/caspase-8-mediated apoptosis. Excitingly, MC2494 displays tumor-preventive activity by blocking 7,12-dimethylbenz(α)anthracene-induced mammary gland hyperproliferation in vivoConclusions: These preventive features might prove useful in patients who may benefit from a recurrence-preventive approach with low toxicity during follow-up phases and in cases of established cancer predisposition. Thus, targeting the newly identified RIP1 complex may represent an attractive novel paradigm in cancer treatment and prevention. Clin Cancer Res; 24(12); 2886-900. ©2018 AACR.
Subject(s)
Histone Acetyltransferases/metabolism , Multiprotein Complexes/metabolism , Neoplasms/metabolism , Nuclear Pore Complex Proteins/metabolism , RNA-Binding Proteins/metabolism , Sirtuins/metabolism , Acetylation , Animals , Antineoplastic Agents/pharmacology , Caspase 8/metabolism , Cell Death/drug effects , Cell Line, Tumor , Gene Expression , Histone Acetyltransferases/genetics , Humans , Mice , Neoplasms/drug therapy , Neoplasms/genetics , Neoplasms/pathology , Nuclear Pore Complex Proteins/genetics , Protein Binding , RNA-Binding Proteins/genetics , Signal Transduction/drug effects , Sirtuins/geneticsABSTRACT
Get well prune: The C-terminal third domain of h-prune is largely unfolded and involved in relevant protein-protein interactions, particularly with Nm23-H1 (see figure), GSK-3ß and gelsolin. This study shows that protein functions mediated by protein-protein interactions can be accurately followed in cell lysates by using fast NMR spectroscopy, which could be easily used for a very efficient NMR drug-discovery strategy.
