Sodium butyrate induces liver cancer cell apoptosis via ATF4/SLC7A11-mediated ferroptosis and mitochondrial damage

Liver cancer, particularly hepatocellular carcinoma, remains a highly aggressive malignancy with significant global morbidity and mortality. Current therapeutic strategies often face limitations, necessitating the exploration of novel approaches. Butyrate, a short-chain fatty acid produced by gut microbiota, has demonstrated anti-cancer properties, yet its precise mechanisms in liver cancer remain largely undefined. Understanding how butyrate exerts its effects could unlock new therapeutic avenues by targeting critical pathways like ferroptosis and apoptosis.

Researchers investigated the anti-cancer effects of sodium butyrate (NaB) on liver cancer cells in vitro and in vivo. In vitro, a CCK-8 cytotoxicity assay was used to assess cell proliferation. They analyzed ATF4 and SLC7A11 expression, levels of malondialdehyde (MDA), reactive oxygen species (ROS), and glutathione (GSH) in NaB-treated cells. Mitochondrial function was evaluated by measuring mitochondrial membrane potential (MMP) and mitochondrial ROS. In vivo, liver cancer models were treated with NaB, and tumor tissues were analyzed for iron content, cytochrome C, caspase9, and caspase3 expression. Control arms included untreated cells/animals, an ATF4 activator, and ferrostatin-1 (Fer-1).

Sodium butyrate treatment significantly suppressed liver cancer cell proliferation, demonstrating its cytotoxic effect. In NaB-treated liver cancer cells, researchers observed a decrease in both ATF4 and SLC7A11 expression. Concurrently, there was an elevation in malondialdehyde (MDA) and reactive oxygen species (ROS) levels, alongside a reduction in glutathione (GSH), indicating induced ferroptosis. These ferroptosis-related changes were effectively reversed by an ATF4 activator. Furthermore, NaB-treated cells exhibited a significant decrease in mitochondrial membrane potential (MMP), accumulation of mitochondrial ROS, and clear signs of mitochondrial damage. This cellular stress disrupted the crucial BAX/BCL-2 balance, leading to the release of cytochrome C, which subsequently activated caspase9 and caspase3, initiating mitochondrial pathway apoptosis. In vivo, NaB treatment resulted in increased iron content within liver cancer tissues, coupled with upregulated cytochrome C and activated caspase9 and caspase3 expression. These effects were notably counteracted by ferrostatin-1 (Fer-1), confirming the involvement of ferroptosis in the observed outcomes.

NaB induces mitochondrial damage via ferroptosis mediated by ATF4/SLC7A11, ultimately triggering mitochondrial pathway apoptosis in hepatoma cells.