In a new study published in Communication of naturea team from Osaka University has developed a technology that streamlines drug discovery using simple molecule tracking. This method allows researchers to explore the effects of many different drug candidates on a single target molecule. Based on the team’s large-scale intracellular single-molecule imaging system, called AiSIS, the technology screens new drugs 100 times faster than standard manual techniques.

The team tested their new method to screen for drugs that can target the epidermal growth factor receptor (EGFR), a molecule central to the development and progression of various types of cancer. Since several drugs that block EGFR are already available to treat lung cancer, this was a good way to determine how well their screening approach worked.

“We used a library of more than 1,000 approved drugs to validate our screening method,” says Daisuke Watanabe, lead author of the study. “We have successfully identified all drugs that are known to target EGFR and are currently used to treat cancer patients. More importantly, we found that the library included seven drugs that were not previously known to affect EGFR.”

The new imaging technique visualizes the behavior of the EGFR following treatment with each drug, allowing the researchers to examine how it reacted. For example, it is now possible to see changes in the assembly and disassembly of target molecules in response to drug treatment, a process known as multimer formation.

“Screening using single-molecule imaging provides a new means of drug discovery by observing the movement of biomolecules in cells and the formation of multimers,” explains lead author Masahiro Ueda. “This has not been used for drug discovery to date and means we should be able to develop new drugs with different mechanisms of action and even repurpose already approved drugs towards new targets.”

Because this study demonstrated that the researchers’ method worked as expected using the well-known EGFR target, they can now use this approach to screen drugs that might hit a number of other receptor targets that are closely involved in the development and disease progression.