Tony B. Travel Award Sample Abstract

Marissa Davies, National Institutes of Health (Postbaccalaureate Trainee)

High-throughput characterization of isozyme-specific Aldehyde Dehydrogenase (ALDH) inhibitors

Aldehyde Dehydrogenases (ALDH) are a family of 19 enzymes that catalyze oxidation of aldehydes to carboxylic acids using NAD(P)+ and have been implicated in several human diseases including cancer. High ALDH activity was shown to sustain cancer stem cell growth and self-renewal, and induce chemotherapy resistance. Hence, development of ALDH inhibitors may provide a promising avenue to treat cancer. However, it remains challenging to dissect the functional role and pathological contribution of individual ALDH isozymes as different tumor types express different levels of each isozyme. Isozyme-selective inhibitors may help overcome this hurdle as well as prevent any toxicity from non-specific ALDH inhibition. Our objective is to identify isozyme-selective inhibitors for ALDH isozymes and expand the chemical probe toolbox for ALDHs to aid in studying ALDHs and developing therapeutics. To this end, we have implemented high-throughput small molecule screening and optimization of lead molecules as well as in silico strategies. Here, we describe a suite of high-throughput assays including biochemical, activity-based, functional, and target-engagement assays to characterize inhibitors. Our focus is the 1A subfamily, ALDH2, and ALDH3A1 due to commercial availability for recombinant proteins, specific antibodies, and cell lines expressing individual isozymes. Thus far, we have identified selective inhibitors for the 1A subfamily, ALDH2, and ALDH3A1 for further study.