Pro-Oxidant and Cytotoxic Effects of Tucum-Do-Cerrado ( Mart.) Extracts in Colorectal Adenocarcinoma Caco-2 Cells.

Colorectal cancer is one of the most common types of cancer. Bioactive natural compounds can act in cancer chemoprevention as tumor growth inhibitors. Tucum-do-cerrado ( Mart.) is a Brazilian fruit that contains several phenolic compounds. This study investigated the effect of tucum aqueous extract in Caco-2 cells in comparison to primary human intestinal organoids and fibroblasts. Cells were exposed to 0.5 and 1 mg/ml of tucum aqueous extract for 24 h. ROS production, mRNA levels for SOD1 and SOD2, CAT, GPX1, NFE2L2, HIF1A and NOS2 were evaluated in Caco-2 cells exposed to tucum extract. Cell viability of Caco-2 cells was decreased upon tucum extract exposure. Mitochondrial ROS levels increased in Caco-2 cells exposed to tucum extract. The mRNA levels of SOD1, SOD2, CAT, GPX, NFE2L2 and HIF1A were downregulated in Caco-2 cells exposed to tucum extract, while NOS2 mRNA levels remained unchanged. Protein levels of SOD2, CAT and NRF2 remained unchanged in Caco-2 cells treated with tucum extract, indicating that catalase and SOD2 cellular functions may be unaffected by the tucum extract at 24 h, of exposure. Aqueous extract of tucum-do-cerrado may induce cellular toxicity in a cancer cell-specific manner, possibly through increased mitochondrial ROS production and gene expression regulation.