Matt Strub Will Present His Research on Wednesday, 2/11/15
DISCOVERY OF DRUGS TO RESCUE ΔF508-CFTR USING A GENOMIC SIGNATURE APPROACH
Matthew D. Strub and Paul B. McCray, Jr.
Background: Cystic fibrosis (CF) is a lethal autosomal recessive disease caused by mutations in the CFTR gene. The most common CFTR mutation, ΔF508, causes protein misfolding, resulting in proteosomal degradation. However, if ΔF508-CFTR is allowed to traffick to the cell membrane, anion channel function may be partially restored. The McCray Lab previously reported that transfection with a miR-138 mimic or knockdown of SIN3A in primary CF airway epithelia increases ΔF508-CFTR mRNA and protein levels, and partially restores cAMP-stimulated Cl- conductance.
Objective: We hypothesized that a genomic signature approach can be used to identify new bioactive molecules affecting ΔF508-CFTR rescue.
The Connectivity Map (CMAP): CMAP is a catalog of gene expression profiles from cells treated with a variety of bioactive molecules and has pattern-matching software to mine data. CMAP queries using miR-138 mimic and SIN3A DsiRNA gene expression signatures identified 27 molecules that mimicked miR-138 and SIN3A DsiRNA treatments. The molecules were screened in vitro for efficacy in improving ΔF508-CFTR trafficking, maturation, and Cl- current. The McCray Lab reported the identification of 4 molecules that partially restored ΔF508-CFTR, highlighting the utility of a genomic signature approach in drug discovery.
LINCS: CMAP has greatly expanded into the Library of Integrated Network-based Cellular Signatures (LINCS). Previously generated gene sets were used to iteratively query LINCS and 125 candidate molecules were selected for further testing. Functional screens performed in CFBE-(ΔF508/ΔF508) cells identified 7/125 compounds that partially rescued ΔF508.
Conclusion: Querying LINCS with relevant genomic signatures offers a novel method to identify new candidates for rescuing ΔF508-CFTR. Further analysis of these molecules and their derivatives are ongoing. We are also generating additional genomic signatures representing ΔF508 rescue for use in LINCS queries. These results represent an important step forward from our proof-of-concept CMAP studies and highlight the utility of LINCS in drug discovery for CF.