Identification of functional leukemia-stromal interactions in the bone marrow niche by RNA interference screening

• Applicant: Professorin Dr. Rebekka Schneider-Kramann
• Subject Area: Pathology
• Term: from 2011 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 214127008

Acute myeloid leukemia (AML) is a paradigm for the study and therapeutic targeting of cancer stem cells. The disease is characterized by increased proliferation and impaired differentiation of hematopoietic stem and progenitor cells. Mesenchymal stem cells (MSC) were shown to play an important role in defining the hematopoietic stem cell niche. The molecular mechanisms that govern this interface are unknown. In order to therapeutically target cancer stem cells in their niche, the regulatory interactions between leukemic stem cells and their niches need to be defined. This project proposes to use an RNA-interference screen on the bone marrow niche represented by MSC- to define a compendium of molecules that act functionally in the LSC/MSC interface. For this purpose, an established and operational platform used for small molecule and shRNA screens in the lab of Prof. Ebert will be used. Fluorescently labelled MSC and LSC will be co-cultured and individual shRNAs will be delivered to the MSC compartment before the cells are co-cultured with LSC. Through functional assays and high content microscopy to quantify cell number, morphology and self-renewal capacity, the effect of the knockdown of a given gene will be evaluated. A list of cell-surface proteins and secreted factors that are candidates for functional screens will be assembled. Hits (i.e. shRNAs that affect LSC in the context of MSC) will be analysed and cross-annotated using analytical tools for RNA-i screening. These hits will be further validated in functional assays in a human LSC/MSC co-culture system in vitro and in vivo. Until now, no systematic analysis of cell surface proteins on MSC that contribute to HSC or LSC biology has been performed. This project will help to identify genes that are essential for the functional engagement of LSC with MSC in the hope of targeting these interactions for diagnosis and therapy in the future.

• DFG Programme: Research Fellowships
• International Connection: USA
• Host: Professor Dr. Benjamin L. Ebert