Exploiting Integrin-αVβ3 to Enhance Radiotherapy Efficacy in Medulloblastoma via Ferroptosis.

Medulloblastoma, a malignant pediatric brain tumor, has a poor prognosis upon relapse, highlighting a critical clinical need. Our previous research linked medulloblastoma cell radioresistance to integrin-αvβ3 expression. β3-depleted (β3_KO) medulloblastoma cells exhibit lipid hydroxyperoxide accumulation after radiotherapy, indicating ferroptosis, a regulated cell death induced by ROS and inhibited by antioxidants such as cysteine, glutathione (GSH), and glutathione peroxidase 4 (GPx4).

Revealing the Ferroptotic Phenotype of Medulloblastoma.

The interaction of iron and oxygen is an integral part of the development of life on Earth. Nonetheless, this unique chemistry continues to fascinate and puzzle, leading to new biological ventures. In 2012, a Columbia University group recognized this interaction as a central event leading to a new type of regulated cell death named "ferroptosis.

N-terminal alanine-rich (NTAR) sequences drive precise start codon selection resulting in elevated translation of multiple proteins including ERK1/2.

We report the discovery of N-terminal alanine-rich sequences, which we term NTARs, that act in concert with their native 5'-untranslated regions to promote selection of the proper start codon. NTARs also facilitate efficient translation initiation while limiting the production of non-functional polypeptides through leaky scanning. We first identified NTARs in the ERK1/2 kinases, which are among the most important signaling molecules in mammals.

Metabolic Rewiring toward Oxidative Phosphorylation Disrupts Intrinsic Resistance to Ferroptosis of the Colon Adenocarcinoma Cells.

Glutathione peroxidase 4 (GPX4) has been reported as one of the major targets for ferroptosis induction, due to its pivotal role in lipid hydroperoxide removal. However, recent studies pointed toward alternative antioxidant systems in this context, such as the Coenzyme Q-FSP1 pathway. To investigate how effective these alternative pathways are in different cellular contexts, we used human colon adenocarcinoma (CRC) cells, highly resistant to GPX4 inhibition.