Small HSPs Inhibitors to Treat Idiopathic Pulmonary Fibrosis – SHOT-IPF
DESCRIPTION OF THE DISEASE AND STATE OF KNOWLEDGE: Idiopathic pulmonary fibrosis (IPF) is a rare, lethal disease with a mean survival of three years. IPF is characterized by the proliferation of myofibroblasts and the accumulation of extracellular-matrix (ECM) in the lungs. Transforming Growth Factor (TGF)-ß1 is the major pro-fibrotic cytokine involved in IPF and is responsible for myofibroblast proliferation, ECM synthesis and transdifferentiation of alveolar epithelial cells into myofibroblasts ( process named EMT). Smad4 is a key TGF-ß1 signal transducer protein
Except for pirfenidone and nintedanib that slightly reduce the annual decline in forced vital capacity compared to placebo, no pharmacologic treatment is currently available.
Heat shock proteins (HSPs) belong to a group of highly conserved proteins, whose expression is induced by different aggressive situations, including inflammation and reactive oxygen species, allowing the cells to survive in otherwise lethal conditions. During the last 20 years, our laboratory has been studying the role of HSPs in different pathological processes and has constructed a number of HSPs inhibitors. Among the different HSPs, small HSPs (sHSPs) and, in particular, HSPB1 and HSPB5 have strong cytoprotective functions which can be explained by their anti-apoptotic properties but also mainly by their role as molecular chaperones for other proteins.
We recently observed that HSPB1 and HSPB5 are strongly overexpressed in human IPF lungs. We have demonstrated that the inhibition of HSPB1 in vivo using the oligonucleotide antisense (ASO) OGX-427, a specific inhibitor of HSPB1 limits pulmonary fibrosis and EMT. We showed that HSPB1 binds to and stabilizes Snail, a major transcription factor involved in EMT. We also demonstrated that the other ubiquitous small chaperone, HSPB5, was essential for the mono-ubiquitination and nuclear translocation of Smad4, a key TGF-ß1 signal transducer protein. We already confirmed the interaction between Smad4 and HSPB5 in vitro.
OBJECTIVES: 1) To discover chemical molecules able to inhibit HSPB1 and/or HSPB5 and 2) To design and produce antisense oligonucleoties (ASO) able to inhibit HSPB5 or both HSPB5 and HSPB1 and also 3) To vectorize OGX427 the ASO specific for HSPB1 that we have already.
DESCRIPTION OF THE PROJECT METHODOLOGY: (1) Our first aim will be to study and model the interaction of HSPB1 and HSPB5 with Snail and Smad4, respectively, in order to well define the druggable domains. (2) The second aim will be to set up a high throughput screening to identify molecules inhibiting HSPB1 and HSPB5. (3) We will select the possible inhibitors by fast in vitro 96 well plates tests: ability to inhibit the chaperones’ anti-aggregation properties and to block the interaction with Snail or Smad4 (with an Octet optic instrument). In parallel, we will develop antisense oligionucleotides (ASO) targeting HSPB5 alone or both HSPB5 and. (4) We will be to test the possible lead candidates in cultured human IPF fibroblasts, tissues and our animal models. (5) We will Vectorize of the most promising candidates will be done using the Inserm Transfert National Plateform RNA-targeting DRUG. For HSPB1 we have already a second generation ASO: OGX-427 (Bonniaud et al. Patent 2011). HSPB5 ASO and OGX-427 will be autonanovectorized using a lipid-conjugated oligonucleotides modification via « Click Chemistry » in order to improve stability, biodisponibility and delivery of the ASO (Patent CT/IB2013/001517/2013).
EXPECTED RESULTS AND IMPACTS: We believe that the discovery of molecules that specifically inhibit HSPB1 and HSPB5 and disrupt their interaction respectively with Snail and with Smad4 may be useful to attenuate or to stop the progression of lung fibrosis. We hope that the combination of these different approaches will allow us at the end of to come out with at least one molecule worth to be tested in clinical trials in IPF therapy
Monsieur Philippe Bonniaud (INSERM - DR GRAND-EST)
The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.
INSERM DR GRAND-EST INSERM - DR GRAND-EST
INSERM - UMR 1068 CRCM INSERM - DR PROVENCE-ALPES CÔTE D'AZUR ET CORSE
INSERM - DR Paris VII Institut national de la sante´ et de la recherche medicale - DR Paris 7
Help of the ANR 536,079 euros
Beginning and duration of the scientific project: September 2016 - 36 Months