1. Trametinib potentiates TRAIL-induced apoptosis via FBW7-dependent Mcl-1 degradation in colorectal cancer cells.
- Author
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Lin L, Ding D, Xiao X, Li B, Cao P, and Li S
- Subjects
- Cell Line, Tumor, Down-Regulation drug effects, Glycogen Synthase Kinase 3 beta metabolism, Humans, Phosphorylation drug effects, Proteasome Endopeptidase Complex metabolism, Protein Binding drug effects, Ubiquitin metabolism, Ubiquitination drug effects, Apoptosis drug effects, Colorectal Neoplasms metabolism, F-Box-WD Repeat-Containing Protein 7 metabolism, Myeloid Cell Leukemia Sequence 1 Protein metabolism, Proteolysis drug effects, Pyridones pharmacology, Pyrimidinones pharmacology, TNF-Related Apoptosis-Inducing Ligand pharmacology
- Abstract
Trametinib is a MEK1/2 inhibitor and exerts anticancer activity against a variety of cancers. However, the effect of Trametinib on colorectal cancer (CRC) is not well understood. In the current study, our results demonstrate the ability of sub-toxic doses of Trametinib to enhance TRAIL-mediated apoptosis in CRC cells. Our findings also indicate that Trametinib and TRAIL activate caspase-dependent apoptosis in CRC cells. Moreover, Mcl-1 overexpression can reduce apoptosis in CRC cells treated with Trametinib with or without TRAIL. We further demonstrate that Trametinib degrades Mcl-1 through the proteasome pathway. In addition, GSK-3β phosphorylates Mcl-1 at S159 and promotes Mcl-1 degradation. The E3 ligase FBW7, known to polyubiquitinate Mcl-1, is involved in Trametinib-induced Mcl-1 degradation. Taken together, these results provide the first evidence that Trametinib enhances TRAIL-mediated apoptosis through FBW7-dependent Mcl-1 ubiquitination and degradation., (© 2020 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)
- Published
- 2020
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