The effect of small molecule inhibitor NSC348884 on nucleophosmin 1-mutated acute myeloid leukemia cells

Objective: Nucleophosmin 1 (NPM1) is a common shuttling protein. Mutation in the NPM1 gene is the most frequent gene alteration in acute myeloid leukemia (AML). This study aims to explore the inhibitory effects of small molecule NSC348884 on wild-type and NPM1-mutated AML cells.

Materials and methods: Immunofluorescence was used to determine the intracellular localization of NPM1 protein in wild-type (OCI-AML2) and NPM1-mutated (OCI-AML3) AML cell lines. The oligomerization state of NPM1 was assessed by Western blot analysis, and the inhibitory effect of NSC348884 on the proliferation of AML cells was evaluated by Cell-counting kit-8 (CCK-8). Flow cytometry was used to detect the proapoptotic effect of NSC348884 on AML cells.

Results: Western blot results showed a significant reduction in the levels of the oligomeric NPM1 protein after the treatment with NSC348884. NSC348884 had an inhibitory effect on the proliferation of both wild-type and NPM1-mutant AML cells. The inhibitory effect on OCI-AML3 cells was stronger, compared to OCI-AML2 cells. Flow cytometry showed that NSC348884 could significantly induce AML cell Apoptosis and had a stronger proapoptotic effect on OCI-AML3 cells.

Conclusions: NSC348884 had inhibitory and proapoptotic effects on both wild-type and NPM1-mutated AML cells. The effect of NSC348884 on AML cells, carrying NPM1 mutation was significantly stronger.