Adapt or Perish: Efficient Selenocysteine Insertion is Critical for Metastasizing Cancer Cells.

During metastasis, cancer cells detach from the primary tumor, circulate through the bloodstream, and establish themselves at distant sites, facing increased levels of reactive oxygen species (ROS) that act as significant barriers to metastatic progression. Adapting to and surviving in these high-ROS environments is thus crucial for successful metastasis. A recent study by Nease and colleagues identified FTSJ1 as the methyltransferase responsible for methylation of the U34 position wobble uridine modification of selenocysteine (Sec) tRNA. This methylation enables efficient Sec insertion, leading to increased translation of a subset of stress-responsive selenoproteins that combat the oxidative stress encountered during the metastatic process. This study establishes FTSJ1 as an essential redox regulator during metastasis through its role in enhancing Sec insertion efficiency, and introduces a potential therapeutic strategy against metastasis.