Abstract B036: NRF2 promotes hepatoblastoma cell migration via mTORC1/2 signaling

Abstract

The purpose of this study was to investigate the mechanism of transcription factor NRF2 in promoting cell migration/metastasis in hepatoblastoma. The role of NRF2 in cell migration was assessed with shRNA knock down of NFE2L2 (NRF2) as well as modulation of NRF2 transcriptional activity with small molecule NRF2 inducer DMF and inhibitor ML385. Proliferation and migration assays found that shNFE2L2 and ML385 decreased both cell proliferation and wound healing ability of HepT1 hepatoblastoma cells. Conversely, DMF increased wound healing ability of HepT1 cells but did not affect cell proliferation. Preliminary data also shows that NRF2 inhibitor ML385 is able to decrease primary tumor growth in an orthotopic PDX model of hepatoblastoma. To determine possible downstream targets of NRF2, bulk RNA sequencing was performed with shNFE2L2 compared to shNS control. Over-representation analysis showed downregulation of known NRF2 functions (xenobiotic metabolism, epithelial-mesenchymal transition) as well as targets less known to be linked to NRF2 function (mTORC1 signaling). To investigate the role of mTOR downstream of NRF2, mTORC1-specific inhibitor ridaforolimus and mTORC1/2-dual inhibitor sapanisertib were assessed in cell migration assays. While both ridaforolimus and sapanisertib decreased wound healing ability, sapanisertib did so to a greater magnitude than ridaforolimus, suggesting an additional role of mTORC2 signaling downstream of NRF2 in cell migration. Co-treatment of NRF2 agonist DMF did not rescue the loss of wound healing seen with ridaforolimus or sapanisertib, suggesting that mTOR signaling acts downstream of NRF2. Overall, our results highlight the importance of NRF2 signaling in promoting cell migration and show that mTOR inhibition may be a viable strategy to treat hepatoblastoma patients that harbor tumors/metastases with increased NRF2 activity. Citation Format: Nicholas A O'Brien, Priyanka Rao, Roma Patel, Brian T Hickner, Andrew Badachhape, Shuai Zhao, Sai Govindu, Sanjeev Vasudevan, Sarah E Woodfield. NRF2 promotes hepatoblastoma cell migration via mTORC1/2 signaling [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Discovery and Innovation in Pediatric Cancer— From Biology to Breakthrough Therapies; 2025 Sep 25-28; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2025;85(18_Suppl_2): nr B036.