ANO6 (TMEM16F) inhibits gastrointestinal stromal tumor growth and induces ferroptosis.

Abstract

Herein, we elucidate the potential role of ANO6 (TMEM16F) in gastrointestinal stromal tumors (GISTs). ANO6 expression in GIST and adjacent normal tissues was determined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting. Cell proliferation, apoptosis, and pyroptosis were examined utilizing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, terminal deoxynucleotidyl transferase dUTP Nick-End Labeling staining, and flow cytometry. In addition, the total iron and Fe2+ levels were assessed. IL-18 and IL-1β levels were also evaluated. Lipid reactive oxygen species (ROS), cystine (Cys), glutathione (GSH), and glutathione peroxidase 4 (GPX4) levels were evaluated using appropriate kits. Ferroptotic markers, including Ptgs2, Chac1, SLC7A11, and SLC3A2, were analyzed by RT-qPCR, western blotting, and immunohistochemistry. ANO6 expression decreased in GIST tissues. ANO6-plasmid inhibits proliferation, induces apoptosis, and promotes pyroptosis in GIST-T1 and GIST-T1 IR cells. The ANO6-plasmid induced ferroptosis, as confirmed by enhanced lipid ROS levels, increased intracellular concentrations of total iron and Fe2+, promoted Ptgs2 and Chac1 expression, reduced Cys, GSH, and GPX4 levels, and downregulated SLC7A11 and SLC3A2 expression after in vitro and in vivo treatment with ANO6-plasmid. Moreover, the ANO6-plasmid inhibited GIST growth in vivo. Therefore, ANO6 may be a promising therapeutic target for blocking the development of GIST via the induction of apoptosis, pyroptosis, and ferroptosis.