METTL1 and neoplasm: Functionally, we discovered that the metabolite 5-formamidoimidazole-4-carboxamide ribotide inhibits cell proliferation and tumor growth in HGSOC by disrupting METTL1-mediated m7G modification of BRCA1. This suggests that 5-formamidoimidazole-4-carboxamide ribotide may hold therapeutic potential for the treatment of HGSOC.