Role of RAS mutant subclones in the development of High Hyperdiploid B-ALL

Objective

In high hyperdiploid acute lymphoblastic leukemia (HeH ALL), RAS-mutant subclones may represent the “RASwaytoALL”, a critical evolutionary route that fuels leukemic progression. HeH ALL is the most common subtype of childhood ALL. Despite its generally favorable prognosis, it remains a major cause of relapse. Genetically, this leukemia is characterized by the gain of multiple chromosomes (51–68 in total) and an intriguing genetic mystery: single-cell DNA sequencing performed by the host laboratory revealed that all studied HeH ALL patients harbor subclonal mutations in RAS pathway genes, arising from the hyperdiploid clone. The biological and clinical significance of these RAS-mutant subclones remains unknown. I hypothesize that RAS-mutant subclones actively contribute to HeH ALL progression and may represent a therapeutically targetable vulnerability. The project has two main objectives: (i) characterize the molecular profile of HeH ALL clones using single-cell multi-omic technologies, focusing on the function of RAS subclonal alterations (ii) assess the functional impact of RAS subclonal alterations in vivo by establishing patient-derived-xenograft (PDX) models and using RAS targeting drugs. I expect to identify expression patterns in RAS-mutated subclones that explain their role in leukemia progression and demonstrate their potential as targets for personalized therapy. The proposal builds on my expertise in omics data analysis, ALL clinical and genetics, and PDX models, along with the pioneering work of the host lab in single-cell technologies, in vivo modelling, and mechanistic studies of ALL. The host institution offers access to cutting-edge facilities and strong collaborative networks. This project will enhance my experimental skills, consolidating my profile as an independent researcher at the interface of genomics, cancer biology, and translational hematology.