Project Details
Projekt
Targetable metabolic dependencies in CLL
Applicants
Dr. Maike Buchner; Ruth Eichner, Ph.D.
Subject Area
Immunology
Term
since 2023
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 505372148
Chronic lymphocytic leukemia (CLL) is one of the most common B cell malignancies in the Western world. While CLL incidence is constantly rising in the West, it is much less common in Asia, which could be attributed to genetics or life-style related factors. Despite novel and successful targeted treatment approaches, which have strongly improved the outcome of CLL, it still remains incurable. Moreover, no therapy has yet proven to be beneficial in patients with early-stage CLL, who are told to “watch and wait” until progression, without having any recommendations on how to improve their outcome. Based on evidence that CLL cells are characterized by a distinct lipid metabolism, we hypothesize that CLL-specific metabolic dependencies represent promising therapeutic targets already at early-stage disease. In this study, we therefore aim to investigate the impact of nutrient availability and the role of nutrient transporters on CLL metabolism and disease progression. Analyzing published datasets, we already identified the nutrient transporters SLC25A1, SLC25A5, and SLC25A20, all related to lipid metabolism, to be associated with poor clinical outcome in CLL. We aim to functionally characterize these SLCs by generating sgRNA-mediated knockouts in the MEC-1 cell line and inhibit SLC function via small molecules in primary CLL cells. We will study the impact on cellular metabolism using Seahorse and SCENITH assays, NAD(P)H imaging, and lipidomics analyses within the consortium and assess the effects on viability and proliferation in vitro and in vivo. In parallel, we will perform loss- and gain-of-function CRISPR/Cas9 screens using MEC-1 cells and available SLC-focused knockout and synergistic activation mediator (SAM) libraries in vitro and in vivo, to identify functionally relevant SLCs not evident from expression data. The most promising hits from the screens will be validated in vitro and in vivo. Furthermore, we have preliminary data revealing that Western diet promotes CLL progression in the TCL1 transgenic CLL mouse model. To determine the underlying mechanisms, we will analyze the metabolic profile and SLC expression in CLL cells from mice following different diets and investigate if effects are directly mediated by nutrients or indirectly via signaling molecules. In addition, we will evaluate the effects of a short-term dietary switch from Western diet to a whole food plant-based diet in therapy-naïve early-stage CLL patients with respect to (lipid) metabolism and proliferative capacity of CLL cells. Using gene expression analysis in CLL cells as well as analysis of serum parameters, we will complement the characterization of the impact of dietary effects to define the underlying mechanism. Taken together, our study is designed to unravel the yet unexplored role of nutrient transporters and nutrition intake on CLL cell metabolism and disease progression as starting point for novel therapeutic approaches.
DFG Programme
Research Units
