Targeting N-myristoylation for therapy of B-cell lymphomas
Erwan Beauchamp, Megan C. Yap, Aishwarya Iyer, Maneka A. Perinpanayagam, Jay M. Gamma, Krista M. Vincent, Manikandan Lakshmanan, Anandhkumar Raju, Vinay Tergaonkar, Soo‐Yong Tan, Soon Thye Lim, Weifeng Dong, Lynne‐Marie Postovit, Kevin D. Read, David W. Gray, Paul G. Wyatt, John R. Mackey, Luc G. Berthiaume
Abstract
Myristoylation, the N-terminal modification of proteins with the fatty acid myristate, is critical for membrane targeting and cell signaling. Because cancer cells often have increased N-myristoyltransferase (NMT) expression, NMTs were proposed as anti-cancer targets. To systematically investigate this, we performed robotic cancer cell line screens and discovered a marked sensitivity of hematological cancer cell lines, including B-cell lymphomas, to the potent pan-NMT inhibitor PCLX-001. PCLX-001 treatment impacts the global myristoylation of lymphoma cell proteins and inhibits early B-cell receptor (BCR) signaling events critical for survival. In addition to abrogating myristoylation of Src family kinases, PCLX-001 also promotes their degradation and, unexpectedly, that of numerous non-myristoylated BCR effectors including c-Myc, NFκB and P-ERK, leading to cancer cell death in vitro and in xenograft models. Because some treated lymphoma patients experience relapse and die, targeting B-cell lymphomas with a NMT inhibitor potentially provides an additional much needed treatment option for lymphoma.