Description

This observational study offers a platform to assess the drug sensitivity of primary leukemia cells ex vivo. The cancer cells are co-cultured in multi-well plates with supporting mesenchymal stroma cells and exposed to a library of both conventional (e.g. steroids, vincristine, asparaginase) as well as targeted chemotherapeutic agents (e.g. tyrosine kinase inhibitors, proteasome inhibitors, B-cell lymphoma 2 (BCL2) inhibitors). Cells are imaged in parallel by high-content microscopy and subsequently segmented and classified by morphology and surface antigen expression. Cell viability is quantified relative to dimethyl sulfoxide (DMSO) and as a function of drug concentration. From the measured cell counts drug-specific sensitivity parameters (e.g. half-maximal inhibitory concentration IC50, maximal inhibition Imax, area under the curve AUC) and their z-scores across the patient cohorts are calculated. Drug response profiles are correlated to clinical response after a steroid pre-phase at day 8 and multiple minimal residual disease (MRD) timepoints measured by flow cytometry (FCM) or polymerase chain reaction (PCR) as defined by the trial protocol. Data on clinical response to treatment and outcome will be enquired from the treating physician. These include the disease stage (initial diagnosis, 1st relapse, 2nd relapse) and time point of sample collection, the clinical trial and treatment arm the patient is enrolled in and/or any individualized drug treatments. Functional profiling data will be integrated with information about genetic lesions (e.g. tumor protein TP53), subtype-defining translocations such as the Philadelphia chromosome t(9;22)(q34;q11) and surface antigen expression (e.g. clusters of differentiation CD7/19/22/33/117). Cytogenetics and molecular profiling data are collected from the treating clinics in collaboration with the international relapsed acute lymphoblastic leukemia (IntReALL) study group and the international Berlin-Frankfurt-Münster (IBFM) network.