Development of Low-Nanomolar Covalent Epoxide Inhibitors of Tubulin Detyrosinating Enzymes VASH1&2

The development of
small molecule inhibitors targeting
the set
of microtubules’ post-translational modifications, also known
as the “tubulin code”, remains an underexplored area
in medicinal chemistry. The recent discovery of the VASH1 and VASH2
enzymes, which are responsible for tubulin detyrosinationa
modification associated with neurodegeneration and cancerprompted
us to develop new molecules that inhibit their activity. In this study,
we conducted the first QSAR analysis of VASH proteases. Through rational
substrate-based design, we identified our lead compound, LV87, as
a potent epoxide-based covalent inhibitor of tubulin detyrosination in cellulo. Specificity assessments against other cysteine
proteases and incubations with nonspecific nucleophiles demonstrated
that LV87 selectively targets VASH1/2. Additionally, safety data,
serum, and microsome stability tests support the notion that LV87
is a selective and potent inhibitor of tubulin detyrosination, paving
the way for further optimization and applications.