Role of GPX4-Mediated Ferroptosis in the Sensitivity of Triple Negative Breast Cancer Cells to Gefitinib

Abstract

Background: Gefitinib exhibits antitumor activity in the patients with breast cancer, but the resistance to gefitinib in triple negative breast cancer (TNBC) is a new concern. Glutathione peroxidase 4 (GPX4) is a leading regulator of ferroptosis, which is of importance for the survival of TNBC cells. This study investigated GPX4-mediated ferroptosis in gefitinib sensitivity in TNBC.Methods: Gefitinib resistant TNBC cells MDA-MB-231/Gef and HS578T/Gef were constructed, and treated with lentivirus sh-GPX4 and ferroptosis inhibitor ferrostatin-1. GPX4 expression, cell viability and apoptosis were detected. Malondialdehyde (MDA), glutathione (GSH), reactive oxygen species (ROS) levels were evaluated. The levels of ferroptosis-related proteins ACSL4, PTGS2, NOX1 and FTH1 were detected. Subcutaneous tumor model was established in nude mice, and gefitinib was intraperitoneally injected. Apoptosis was detected by TUNEL staining and Ki-67 expression was detected by immunohistochemistry.Results: GPX4 was increased in gefitinib-resistant cells. After silencing GPX4, the inhibition rate of cell viability increased, the limitation of colony formation ability reduced, apoptosis rate increased, and the sensitivity of cells to gefitinib was improved. After silencing GPX4, MDA level and ROS production were significantly increased, while GSH level was decreased. Silencing GPX4 promoted ferroptosis. After inhibition of ferroptosis by ferrostatin-1, it revealed that inhibition of GPX4 promoted gefitinib sensitivity by promoting cell ferroptosis. In vivo experiments also showed that inhibition of GPX4 enhanced the anticancer effect of gefitinib through promoting ferroptosis.Conclusion: Inhibition of GPX4 stimulated ferroptosis and thus enhanced TNBC cell sensitivity to gefitinib.

The role of ferroptosis‐related genes for overall survival prediction in breast cancer

“…Although numerous studies 10–13 have investigated the genes that might regulate cancer cell death through ferroptosis, their correlations with prognosis remain worth exploring. In this article, we explored the expression levels of 259 ferritinophagy‐related genes in breast cancer.…”

Diet, lipids, and antitumor immunity

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Forsythoside A Mitigates Alzheimer's-like Pathology by Inhibiting Ferroptosis-mediated Neuroinflammation via Nrf2/GPX4 Axis Activation

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