EIF1AX and RAS mutations cooperate to drive thyroid tumorigenesis through ATF4 and C-MYC

Citations of this article
Mendeley users who have this article in their library.
Get full text


Translation initiation is orchestrated by the cap binding and 43S preinitiation complexes (PIC). Eukaryotic initiation factor 1A (EIF1A) is essential for recruitment of the ternary complex and for assembling the 43S PIC. Recurrent EIF1AX mutations in papillary thyroid cancers are mutually exclusive with other drivers, including RAS. EIF1AX mutations are enriched in advanced thyroid cancers, where they display a striking co-occurrence with RAS, which cooperates to induce tumorigenesis in mice and isogenic cell lines. The C-terminal EIF1AX-A113splice mutation is the most prevalent in advanced thyroid cancer. EIF1AX-A113splice variants stabilize the PIC and induce ATF4, a sensor of cellular stress, which is co-opted to suppress EIF2α phosphorylation, enabling a general increase in protein synthesis. RAS stabilizes c-MYC, an effect augmented by EIF1AX-A113splice. ATF4 and c-MYC induce expression of amino acid transporters and enhance sensitivity of mTOR to amino acid supply. These mutually reinforcing events generate therapeutic vulnerabilities to MEK, BRD4, and mTOR kinase inhibitors. Significance: Mutations of EIF1AX, a component of the translation PIC, co-occur with RAS in advanced thyroid cancers and promote tumorigenesis. EIF1AX-A113splice drives an ATF4-induced dephosphorylation of EIF2α, resulting in increased protein synthesis. ATF4 also cooperates with c-MYC to sensitize mTOR to amino acid supply, thus generating vulnerability to mTOR kinase inhibitors.




Krishnamoorthy, G. P., Davidson, N. R., Leach, S. D., Zhao, Z., Lowe, S. W., Lee, G., … Fagin, J. A. (2019). EIF1AX and RAS mutations cooperate to drive thyroid tumorigenesis through ATF4 and C-MYC. Cancer Discovery, 9(2), 264–281. https://doi.org/10.1158/2159-8290.CD-18-0606

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free