NRAS knockdown reverses monocytic cell state and resensitizes resistant FLT3-AML cells to gilteritinib [primary AML RNA-Seq]

Gilteritinib resistance is commonly driven by the emergence of NRAS mutations and a shift towards a more monocytic cell state. We hypothesized that directly targeting and depleting NRAS protein would reverse these adaptive differentiation changes and restore therapeutic sensitivity.

To test this, we utilized a mutation-agnostic antisense oligonucleotide (ASO) to selectively knock down NRAS expression across gilteritinib-resistant AML cell lines, in vivo cell-line-derived xenografts, and primary patient samples. NRAS ASO successfully resensitized gilteritinib resistant cells with multiple distinct NRAS mutations, displaying superior efficacy compared to downstream MEK inhibition. This therapeutic efficacy was independent of NRAS mutant variant allele frequency, suggesting that wild-type NRAS may also contribute to resistance.