In particular, we showed that, in the context of both truncating (p.D335fs) and elongating (pH433fs, pS410fs) GATA3 mutations, inhibition of MDM2 hampers cancer cell proliferation and tumor growth in vitro, in three independent in vivo models (zebrafish, CAM and canonical PDX) and in two GATA3-mutant PDOs. Here, GATA3 is linked to cancer.