SLC7A11 suppresses paclitaxel resistance and improves survival via the KLF2 regulatory axis associated with autophagy in ovarian cancer

Abstract

SLC7A11 is well-established as a key mediator of ferroptosis. However, its functional role in regulating autophagy, particularly in the context of ovarian cancer (OC) chemoresistance, remains poorly characterized. Our preliminary results suggested that low SLC7A11 expression is associated with paclitaxel resistance in OC, likely through inhibition of autophagy. Despite this initial observation, systematic functional investigations into the role of SLC7A11 in autophagy regulation and OC chemoresistance are lacking, and the underlying molecular mechanisms remain unclear. Therefore, this study aims to elucidate how SLC7A11 mediates chemoresistance in OC through the regulation of autophagy. The effects of SLC7A11 modulation were assessed in paclitaxel-resistant and parental OC cells using functional assays. Autophagy was evaluated via transmission electron microscopy, immunofluorescence, and Western blotting. Autophagy was inhibited using 3-methyladenine or LC3B knockdown. A subcutaneous xenograft model was used for in vivo validation. Clinical relevance was analyzed using patient tissues. Proteomics, bioinformatics, molecular, and CCK-8 assays were integrated to investigate the SLC7A11/KLF2-autophagy axis. SLC7A11 knockdown enhanced the viability of paclitaxel-resistant OC cells (HeyA8-R) following paclitaxel treatment. In contrast, SLC7A11 overexpression sensitized both HeyA8-R cells and their parental HeyA8 cells to paclitaxel, as evidenced by reduced viability, increased intracellular paclitaxel accumulation, and elevated DNA damage. Moreover, SLC7A11 overexpression augmented autophagy-associated activity, and inhibition of autophagy partially attenuated SLC7A11-mediated sensitization to paclitaxel. In vivo studies showed that SLC7A11 suppressed tumor growth and overcame paclitaxel resistance in OC, accompanied by upregulated autophagy-related markers (LC3B, LC3B-II/I, and LAMP1). Mechanistically, SLC7A11 negatively regulated KLF2, a key oncogenic autophagy regulator, and the SLC7A11/KLF2 regulatory axis was associated with LC3B expression and autophagy-associated activity, which may contribute to paclitaxel sensitivity in OC. Clinically, low SLC7A11 expression correlated with chemoresistance and shorter survival in OC. Our findings underscore the significance of the SLC7A11/KLF2-autophagy regulatory axis in OC paclitaxel resistance. They also suggest that SLC7A11 may serve as a prognostic biomarker and therapeutic target for overcoming OC chemoresistance.