RNA methyltransferase 3 drives pancreatic acinar cell carcinoma growth and is a therapeutic target

Mettl3 overexpression significantly accelerated ACC development and enhanced tumor aggressiveness. The SAM-binding domain proved essential for tumor formation, as deletion mutants failed to promote carcinogenesis. MeRIP-seq revealed preferential methylation of cell cycle and DNA replication genes in Mettl3-overexpressing tumors. scRNA-seq analysis demonstrated enhanced malignancy signatures, including epithelial-to-mesenchymal transition and TGF-β signaling.

METTL3 promoted PRSS1-mediated signaling from ACC cells to inflammatory cancer-associated fibroblasts, creating a feed-forward loop involving IGF1 that amplifies tumor growth. Conditional Mettl3 deletion induced rapid tumor apoptosis. Pharmacological inhibition with STM2457 similarly triggered caspase-3/7-dependent apoptosis in pancreatic tumors.

METTL3-mediated RNA methylation drives ACC pathogenesis through tumor-intrinsic cell cycle regulation and tumor-extrinsic stromal interactions. These findings establish METTL3 as a promising therapeutic target and provide mechanistic insights supporting clinical development of METTL3 inhibitors for pancreatic cancer treatment.