RESEARCH The human genome encodes more than 1,600 transcription factors (TFs), along with additionalcofactors, chromatin regulators, and structural proteins that collectively execute the regulatoryinstructions encoded within the nuclear DNA. Dysfunctions of these proteins, collectively knownas Gene Regulatory Proteins (GRPs), are known to drive multiple diseases such as cancer,inflammation-related, and neurological conditions. In cancer, these proteins are frequentlyrearranged and fused to create new proteins which cause the initiation and progression ofvarious types of leukemia, sarcoma and other tumors. Despite the importance of these proteins,GRPs have been considered undruggable due to challenges in modeling their activity in vitro.We have solved these shortcomings by implementing an in-cell functional proteomics drugdiscovery platform that quantifies the effects of small-molecules on the abundance of GRPsbound to the genome in a diversity of cell and tissue types. The platform is based on ChromatinExtraction by Salt Separation, coupled to Data Independent Analysis mass spectrometry(ChESS-DIA), which was recently reported. In this proposal, we will apply this technology fordrug development of oncogenic fusion proteins. First, we will use Mixed Lineage Leukemia(MLL) rearranged leukemia to perform technology development of the oncogenic fusion proteinproteomics strategy. MLL rearrangements are found in a subset of AML and ALL patients,commonly in children, and remain challenging to treat with existing therapeutic options. Severaldrug candidates for MLL-rearranged leukemia are currently in clinical trials, and these will beused to validate the accuracy of the ChESS-DIA assay for reporting the ability of MLL-targetingcompounds to disrupt the MLL complex in live cells. With a validated MLL ChESS-DIA assay,we will then conduct a pilot screen to prove the assay's utility in a screening setting, using theNational Cancer Institute's Mechanistic Diversity compound set supplemented with knowninhibitors of the MLL complex. These compounds contain a diverse array of bioactivities, manyof which act through unknown mechanisms. This provides an opportunity to find newcompounds capable of disrupting the MLL complex. Lastly, we will use the roadmap developedfor MLL to develop ChESS-DIA assays for many of the common oncogenic fusions, thendevelop a method to unify these assays together in a single, unified, in-cell assay for oncogenicfusion proteins.
Public Health Relevance Statement: PROJECT NARRATIVE
This research aims to develop a technology to enable drug development for gene regulators in
cancer. Traditional tools to study these proteins have proven ineffective, so we are developing
an in-cell system that specifically tests a drug's ability to block cancer-causing gene regulators.
Project Terms: | <0-11 years old> | |
