omation mbers - Society for Laboratory Automation and Screening

9:00 am Wednesday, February 4 Emerging Technologies – Cell Based Screening Room A3
Rowan Stringer
Novartis Horsham Research Centre
Wimblehurst Road, Horsham
West Sussex, Nr London, RH12 5AB United Kingdom
rowan.stringer@pharma.novartis.com
96-well Protein-binding Studies in Drug Discovery
126
Co-Author(s)
Rachael Profit
Sarah Beech
Paul Nicklin
The protein-binding properties of 95 commercially available drugs were assessed using a 96-well ultrafiltration
device (Millipore Multiscreen Ultracel ® -PPB). This system has low non-specific binding, good intra- and interexperiment
reproducibility and can be coupled with higher-throughput bioanalysis. Results generated using
this new method had good agreement with literature values for these reference compounds (R2 – 0.89); e.g.,
bupivacaine 93% (95%), alprazolam 69% (71%), betaxolol 44% (55%), trimethoprim 43% (37%) and tocainide
10% (10%), literature values in parentheses. This plasma protein-binding assay offers advantages over single
ultrafiltration devices and equilibrium dialysis methods in terms of speed, convenience and automation potential. It
will be used to provide initial protein-binding results to support early drug discovery programs.
9:15 am Wednesday, February 4 Emerging Technologies – Cell Based Screening Room A3
Ben Tseng
Maxim Pharmaceuticals
6650 Nancy Ridge Drive
San Diego, California 92121
btseng@maxim.com
Co-Author(s)
Sui Xiong Cai, John Drewe,
John Herich, Shailaja Kasibhatla
A Drug Discovery Screen and Chemical-Genetic Approach for Novel Apoptosis Inducers
We have developed and implemented a cell-based high throughput screen for anti-cancer drug discovery for
the induction of apoptosis by measuring the downstream effector caspase 3. A proprietary pro-fluorescence
substrate is used in the assay that is robust and suited for high throughput applications and has a Z´ factor of 0.8.
A cell-based assay provides the advantages of identifying compounds that induce apoptosis through any one of
multiple pathways as well as through new and novel targets. In addition, the compounds that are identified have
bioactivity on cells. From the primary and confirmatory dose response screens, selected compounds are assayed
and classified for their different effects on cell cycle progression or non-progression prior to activation of apoptosis.
Additional molecular assays provide a refinement of these categories. These categorizations identify compounds
that activate apoptosis through different and potentially novel mechanisms. Based on several selection criteria,
the promising compounds are selected for analog synthesis to provide structure activity relationships as well as
to improve compound properties. Analogs that meet these additional criteria are progressed to in vivo studies and
to molecular target identification studies. We will present examples of two compounds discovered in our screens,
their novel mechanisms of action, their in vivo activities, as well as target identification and validation strategies.
Our chemical-genetic based program allows the discovery of novel pathways and targets for activating apoptosis
and for the discovery of novel compounds that affect these pathways as potential anti-cancer agents.