Ferroptosis has emerged as an actionable target to eliminate therapy-resistant and metastatic cancers1. However, which ferroptosis surveillance systems may offer a therapeutic window to leverage redox maladaptation in cancer remains unclear. In melanoma, glutathione peroxidase 4 (GPX4) impedes ferroptosis during haematogenous metastasis, but is dispensable during lymphatic metastasis2. Here, using a metastatic mouse melanoma model selected for lymph node metastasis, we show that lymph-node-derived metastatic cells exhibit markedly diminished expression of glutamate-cysteine ligase (GCLC) and reduced glutathione (GSH) levels relative to their parental counterparts. This metabolic shift occurs within the hypoxic lymphatic niche. Under comparable low-oxygen conditions, GPX4 undergoes ubiquitination and proteasomal degradation. In response, lymph node metastatic cells acquire increased reliance on ferroptosis suppressor protein 1 (FSP1), which is localized with perinuclear lysosomes. These findings reveal that the reduced reliance on the GPX4 axis enables melanoma cells to shift toward FSP1 dependency. Notably, intratumoural monotherapy with selective FSP1 inhibitors (viFSP1 and FSEN1) effectively suppresses melanoma growth in lymph nodes, but not in subcutaneous tumours, emphasizing a microenvironment-specific dependency on FSP1. Thus, targeting FSP1 in the lymph nodes holds strong potential for blocking melanoma progression.
FörderungenAgence Nationale de la Recherche Institut National du Cancer Fondation Bettencourt Schueller Deutsche Forschungsgemeinschaft (DFG) Fondation Charles Defforey-Institut de France Ligue Contre le Cancer (Equipe Labellisee) NCI Arc Institute Fellowship METAvivor Early Career Investigator Award Cause Breast Cancer Foundation NIH Melanoma Research Foundation Young Career Investigators Award Ludwig Center at Harvard European Research Council DFG Priority Program SPP 2306
EU-H2020 ERC starting grant Ministry of Culture and Science of the State of North Rhine-Westphalia German Research Foundation European Research Council (ERC) CRC TRR 353 Melanoma Research Program Department of Defense Team Science Award