STING-mediated degradation of IFI16 negatively regulates apoptosis by inhibiting p53 phosphorylation at serine-392. (PubMed, J Biol Chem)
Here, our results from flow cytometry apoptosis detection and immunoblots assays show that IFI16 and Nutlin-3, a p53 pathway activator, synergistically induce apoptosis in U2OS and A549 cells...However, overexpression of STING suppressed p53 Ser392 phosphorylation, p53 transcriptional activity, p53-target gene expression, and p53-dependent mitochondrial depolarization and apoptosis. In summary, our current study demonstrates that STING-mediated IFI16 degradation negatively regulates IFI16 mediated p53-dependent apoptosis in osteosarcoma and non-small cell lung cancer (NSCLC) cells, which suggests a pro-tumorigenic role for STING in certain cancer types due to its potent ability to degrade upstream IFI16.