Targeted degradation of METTL3 against acute myeloid leukemia and gastric cancer.

Accumulating evidence reveals the oncogenic role of methyltransferase-like 3 (METTL3) in a variety of cancers, either dependent or independent of its m6A methyl transferase activity. We have explored PROTACs targeting METTL3 and identified KH12 as a potent METTL3 degrader. Treatment of KH12 on MOLM-13 cells causes degradation of METTL3 with a DC50 value of 220 nM in a dose-, time- and ubiquitin-dependent fashion. In addition, KH12 is capable of reversing differentiation and possesses anti-proliferative effects surpassing the small molecule inhibitors on MOLM-13 cells. Notably, we first present that METTL3 degrader significantly suppresses the growth of various gastric cancer (GC) cells, where the m6A-independent activity of METTL3 plays a crucial role in tumorigenesis. The anti-GC effects of KH12 were further confirmed in patient-derived organoids (PDOs). This study offers therapeutic potentials of targeted degradation of METTL3 against GC implicated with non-catalytic function of METTL3 as well as against AML.