iScience. 2025 Apr 18. 28(4): 112219
DDX5 is a DEAD-box RNA helicase that is overexpressed and implicated in the progression of several cancers, including small cell lung cancer (SCLC). Our laboratory has demonstrated that DDX5 is essential for the invasive growth of SCLC and mitochondrial respiration. SCLC is an extremely lethal, recalcitrant tumor, and currently lacking effective treatments. Supinoxin (RX 5902), a compound having anti-cancer activity, is a known target of phosphor-DDX5. We now report that Supinoxin inhibits the proliferation of chemo-sensitive and chemo-resistant SCLC lines, H69 and H69AR, respectively. Additionally, Supinoxin mitigates both the growth of H69AR xenograft tumors and SCLC PDX tumors in vivo. Finally, we find that Supinoxin inhibits expression of mitochondrial genes and effectively blocks respiration. These studies suggest that Supinoxin functions in anti-tumor progression by reducing cellular energy levels through DDX5.
Keywords: Cancer; Molecular biology; Transcriptomics