METTL1 and osteosarcoma: As a key methyltransferase involved in m7G modification, METTL1 has been implicated in the methylation of m7G sites in multiple target genes, showing close associations with the progression and poor prognosis of diverse cancers such as glioblastoma (Wang et al. 2024), liver cancer (Dong et al. 2024), osteosarcoma (Wang et al. 2023), and castration-resistant prostate cancer (Zhang et al. 2023).