New Treatment Modalities for Colorectal Cancer Through Simultaneous Suppression of FSP1 and GPX4.

Background/aim: Ferroptosis is a nonapoptotic type of cell death that is dependent on iron and involves the accumulation of reactive oxygen species. Ferroptosis suppressor protein 1 (FSP1) and glutathione peroxidase 4 (GPX4) are ferroptosis regulators that inhibit ferroptosis through independent pathways. This study assessed the prognostic value of GPX4 and FSP1 expression in colorectal cancer (CRC). We also examined the effects of FSP1 and GPX4 inhibition on cell survival of CRC cells.

Materials and methods: This study included 206 surgical specimens from Stage II or III CRC patients. FSP1 and GPX4 expression was analyzed immunohistochemically, and the association of their expression levels with clinical outcome was evaluated. We also examined the effects of FSP1 and GPX4 inhibitors on the cell proliferative capacity of CRC cell lines.

Results: Overall survival and recurrence-free survival were reduced in patients with high expression of FSP1 or GPX4, and those with both GPX4 and FSP1 expression showed worse prognosis. Positivity of both FSP1 and GPX4 was an independent poor prognostic factor for CRC patients. In CRC cells, the combination of GPX4 and FSP1 inhibitors led to more effective cell death than either inhibitor alone.

Conclusion: High expression of both GPX4 and FSP1 is a significant poor prognostic factor for CRC. Simultaneous inhibition of GPX4 and FSP1 to induce ferroptosis may be a novel therapeutic strategy in CRC.