E3 ubiquitin ligase DTX2 fosters ferroptosis resistance via suppressing NCOA4-mediated ferritinophagy in non-small cell lung cancer

Abstract

Non-small cell lung cancer (NSCLC) remains the foremost contributor to cancer-related fatalities globally, with limited effective therapeutic modalities. Recent research has shed light on the role of ferroptosis in various types of cancers, offering a potential avenue for improving cancer therapy. Herein, we identified E3 ubiquitin ligase deltex 2 (DTX2) as a potential therapeutic target candidate implicated in promoting NSCLC cell growth by inhibiting ferroptosis. Our investigation revealed a significant upregulation of DTX2 in NSCLC cells and tissues, which was correlated with poor prognosis. Downregulation of DTX2 suppressed NSCLC cell growth both in vitro and in vivo, while its overexpression accelerated cell proliferation. Moreover, knockdown of DTX2 promoted ferroptosis in NSCLC cells, which was mitigated by DTX2 overexpression. Mechanistically, we uncovered that DTX2 binds to nuclear receptor coactivator 4 (NCOA4), facilitating its ubiquitination and degradation via the K48 chain, which subsequently dampens NCOA4-driven ferritinophagy and ferroptosis in NSCLC cells. Notably, DTX2 knockdown promotes cisplatin-induced ferroptosis and overcomes drug resistance of NSCLC cells. These findings underscore the critical role of DTX2 in regulating ferroptosis and NCOA4-mediated ferritinophagy, suggesting its potential as a novel therapeutic target for NSCLC.