RESUMEN
SUMMARY: Fahrner and colleagues investigated the immune response of patients with cancer and cancer-free individuals to SARS-CoV-2 and found that a propensity toward an IL5-predominant Th2/Tc2 response was predictive of susceptibility to infection. The results of this study also suggest that a cellular response against the Spike 1 protein receptor binding domain (S1-RBD) region of the SARS-CoV-2 proteome contributes to protection and that mutations in this region may drive viral evolution and immune escape. See related article by Fahrner et al., p. 958 (8).
Asunto(s)
COVID-19 , COVID-19/genética , Humanos , Glicoproteínas de Membrana/genética , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/genética , Linfocitos T/metabolismo , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/inmunología , Proteínas del Envoltorio Viral/metabolismoRESUMEN
Gilteritinib is a potent and selective FLT3 kinase inhibitor with single-agent clinical efficacy in relapsed/refractory FLT3-mutated acute myeloid leukemia (AML). In this context, however, gilteritinib is not curative, and response duration is limited by the development of secondary resistance. To evaluate resistance mechanisms, we analyzed baseline and progression samples from patients treated on clinical trials of gilteritinib. Targeted next-generation sequencing at the time of AML progression on gilteritinib identified treatment-emergent mutations that activate RAS/MAPK pathway signaling, most commonly in NRAS or KRAS. Less frequently, secondary FLT3-F691L gatekeeper mutations or BCR-ABL1 fusions were identified at progression. Single-cell targeted DNA sequencing revealed diverse patterns of clonal selection and evolution in response to FLT3 inhibition, including the emergence of RAS mutations in FLT3-mutated subclones, the expansion of alternative wild-type FLT3 subclones, or both patterns simultaneously. These data illustrate dynamic and complex changes in clonal architecture underlying response and resistance to mutation-selective tyrosine kinase inhibitor therapy in AML. SIGNIFICANCE: Comprehensive serial genotyping of AML specimens from patients treated with the selective FLT3 inhibitor gilteritinib demonstrates that complex, heterogeneous patterns of clonal selection and evolution mediate clinical resistance to tyrosine kinase inhibition in FLT3-mutated AML. Our data support the development of combinatorial targeted therapeutic approaches for advanced AML.See related commentary by Wei and Roberts, p. 998.This article is highlighted in the In This Issue feature, p. 983.