Lenvatinib triggers an EGR1-ZNF768-SLC7A11 adaptive response to limit ferroptosis-mediated therapeutic efficacy in hepatocellular carcinoma.

Abstract

Objective: Adaptive therapeutic tolerance frequently limits first-line lenvatinib efficacy in hepatocellular carcinoma (HCC). This study explored the C2H2-type zinc finger (ZNF) protein family (the largest class of transcription factors) and hypothesized that specific members of the ZNF protein family are hijacked by cancer cells to orchestrate pro-survival defenses against lenvatinib-induced ferroptosis.

Methods: We implemented a hypothesis-driven integrative multi-omics strategy to identify clinically relevant ZNF drivers. The top candidate, ZNF768, was functionally investigated using lentiviral modulation in HCC cell lines and subcutaneous xenograft models. Mechanistic elucidation was performed through ChIP-qPCR, luciferase reporter assays, and upstream signaling pathway analysis. The therapeutic synergy of an AAV-shZNF768 vector combined with lenvatinib was evaluated in vivo.

Results: ZNF768 was identified as a potent transcriptional driver of pro-survival programs in HCC; high expression correlated with poor patient prognosis. ZNF768 knockdown suppressed proliferation and robustly sensitized HCC cells to ferroptosis, which was marked by uncontrolled lipid peroxidation and GSH depletion. ZNF768 directly transactivated the SLC7A11 promoter, reinforcing the cellular antioxidant shield. We uncovered a paradoxical therapy-induced feedback loop in which lenvatinib inhibits AKT signaling, leading to EGR1 accumulation and transcriptional activation of ZNF768. This adaptive response limits the efficacy of lenvatinib. Consequently, disrupting this loop via ZNF768 knockdown synergizes with lenvatinib to trigger robust ferroptosis and profoundly suppress tumor growth in vivo.

Conclusions: The EGR1-ZNF768-SLC7A11 axis constitutes a critical adaptive shield limiting lenvatinib efficacy in HCC. ZNF768 serves as a predictive biomarker and a high-value therapeutic target. Disrupting this axis offers a rational strategy to overcome therapeutic resistance and maximize the clinical potential of lenvatinib.