High-content screening of 1,200 Prestwick Chemical Library compounds.

HeLa cells stably expressing firefly luciferase under control of NDST1 promoter were treated with compounds from the Prestwick Chemical Library. The reporter activity of the tested compounds is expressed relative to the mean activity of DMSO treated cells. Drugs showing cytotoxic effects, as tested in parallel by the Hexosaminidase assay, were removed from the graph. Thirty eight compounds resulting in the luminescence decrease by >75% relative to the mean of DMSO control were considered as potentially strong NDST1 inhibitors (shown in red). Seven compounds (shown in green) increased luminescence by ≥ 30% over the mean DMS control. These compounds could be considered as potential inducers of NDST1 expression. Eight potentially strong inhibitors and 2 average inhibitors (indicated by blue circles) were selected for the dose-response assessment (Fig 4A). Experiments were performed in triplicates. Abbreviation: stdev–standard deviation.