The REV1-Targeting Inhibitor JH-RE-06 Triggers Programmed Cell Death by Regulating NCOA4-Mediated Ferritinophagy and the KEAP1-NRF2-ARE Pathway in CRC Cells

Abstract Oncogenes accelerate DNA replication, triggering excessive replication origin activation. This leads to DNA replication stress and genomic instability in cancer cells, making replication stress a potential therapeutic target. Translesion synthesis (TLS) serves as a compensation mechanism for replication stress, enabling cancer cells to acquire a growth advantage. Cancer cells exploit translesion synthesis (TLS) to circumvent DNA adducts produced by platinum-based chemotherapeutics, leading to the emergence of resistance. Consequently, targeting TLS offers a dual advantage for oncological therapy. The application of the translesion synthesis polymerase REV1 inhibitor JH-RE-06 in the treatment of colorectal cancer (CRC) remains unexplored. The molecular mechanisms by which JH-RE-06 induces programmed cell death have also not been reported. Our findings revealed that JH-RE-06 could trigger programmed cell death in CRC cells.Specifically, JH-RE-06 enhances the level of cleaved caspase-3 and cleaved PARP1 in cancer cells, stimulates NCOA4-mediated ferritinophagy, which results in ferroptosis. Cells activate the KEAP1-NRF2 pathway in response to the oxidative stress caused by JH-RE-06. This programmed cell death (PCD) can be reversed by cysteine-synthesizing pharmaceuticals. While JH-RE-06 does not increase the sensitivity of CRC cells to oxaliplatin, it effectively suppresses clonal proliferation of oxaliplatin-resistant cell lines in vitro and inhibits oxaliplatin-resistant xenograft tumors growth in vivo. The data indicate that JH-RE-06 may serve as a viable second-line chemotherapeutic treatment for CRC in cases of chemoresistance.