Using Western blot assays to detect ferroptosis-related proteins in the cancer cells after PPI treatment in vitro, we found that PPI downregulated the expression of both NRF2 and FTH1 (Figure 6A) in both AGS and MKN-45 cancer cells, whereas Liproxstain-1 largely reversed this effect of PPI (Figure 6B), indicating that PPI-induced ferroptosis in the gastric cancer cells is associated with its regulation of NRF2/FTH1 pathway. Here, FTH1 is linked to gastric cancer.