1
|
Komarov AP, Komarova EA, Green K, Novototskaya LR, Baker PS, Eroshkin A, Osterman AL, Chenchick AA, Frangou C, Gudkov AV. Functional genetics-directed identification of novel pharmacological inhibitors of FAS- and TNF-dependent apoptosis that protect mice from acute liver failure. Cell Death Dis 2016; 7:e2145. [PMID: 26986512 PMCID: PMC4823946 DOI: 10.1038/cddis.2016.45] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 01/25/2016] [Accepted: 02/04/2016] [Indexed: 12/12/2022]
Abstract
shRNA-mediated gene-silencing technology paired with cell-based functional readouts reveals potential targets directly, providing an opportunity to identify drugs against the target without knowing the precise role of the target in the pathophysiological processes of interest. By screening a lentiviral shRNA library targeting for major components of human signaling pathways and known drug targets, we identified and validated both canonical as well as 52 novel mediators of FAS and TNF ligand-induced apoptosis. Presence of potential therapeutic targets among these mediators was confirmed by demonstration of in vivo activity of siRNAs against four identified target candidates that protected mice from acute liver failure (ALF), a life-threatening disease with known involvement of death receptor (DR)-mediated apoptosis. Network-based modeling was used to predict small-molecule inhibitors for several candidate apoptosis mediators, including somatostatin receptor 5 (SSTR5) and a regulatory subunit of PP2A phosphatase, PPP2R5A. Remarkably, pharmacological inhibition of either SSTR5 or PPP2R5A reduced apoptosis induced by either FASL or TNF in cultured cells and dramatically improved survival in several mouse models of ALF. These results demonstrate the utility of loss-of-function genetic screens and network-based drug-repositioning methods for expedited identification of targeted drug candidates and revealed pharmacological agents potentially suitable for treatment of DR-mediated pathologies.
Collapse
Affiliation(s)
| | - E A Komarova
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - K Green
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - L R Novototskaya
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - P S Baker
- Buffalo BioLabs, LLC, Buffalo, NY, USA
| | - A Eroshkin
- Infectious and Inflammatory Disease Center, Sanford-Burnham-Prebys Medical Discovery Institute, La Jolla, CA, USA
| | - A L Osterman
- Buffalo BioLabs, LLC, Buffalo, NY, USA.,Infectious and Inflammatory Disease Center, Sanford-Burnham-Prebys Medical Discovery Institute, La Jolla, CA, USA
| | | | - C Frangou
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - A V Gudkov
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Buffalo, NY, USA
| |
Collapse
|
2
|
Abstract
Interferon regulatory factors (IRFs) regulate the transcription of both interferon-inducible genes and interferons themselves. Along with the N-terminal, DNA-binding, winged-helix domain, most IRFs contain the C-terminal domains that are shown to be related to the C-terminal domains in the proteins of the Smad family that mediate transcription activation in the transforming growth factor response pathway. Comparison of the IRF-Smad alignment to the known three-dimensional structure of human tumor suppressor Smad4 suggests that a conserved loop, equivalent to Loop 3 in Smad 4, is a determinant of protein-protein interaction in IRFs.
Collapse
Affiliation(s)
- A Eroshkin
- Department of Computational Sciences, Axys Pharmaceuticals, La Jolla, CA 92037, USA
| | | |
Collapse
|