Tumour screening: making resistance futile?

Rebecca BazeleyMonday, 24 November 2014

Cancer treatments are at the frontline of personalised approaches to healthcare, with genetic testing and analysis of tumours allowing the use of the most effective drugs to attack them, including new biologically targeted treatments that can be highly effective without the side-effects (toxicity) of wider-acting drugs.

However, as with infectious pathogens, tumours can become resistant to even the most powerful prescribed treatment, often within a few months, rendering the patient’s original course of therapy futile.

Building on recent advances in cell culture techniques, a team at Massachusetts General Hospital are further focusing ‘personalisation’ on the tumour itself. Led by Jeffrey Engelman, the researchers took tumour cells from 20 patients with drug-resistant lung cancer and then targeted the cells with an array of 76 drugs, in order to identify which drugs, or more often which combination of drugs, the cells were unable to combat. An effective combination of drugs was found for almost all the cells lines.

Transplanted into mice, the human tumours continued to shrink when given the combination of drugs. The drugs remained active nearly twice as long as the single drug in suppressing tumour growth. Writing inScience, the researchers report that they found multiple effective drug combinations based on tumour cell screening that were not predicted by standard genetic tumour analysis alone.

This drug screening could help side step many of the unanswered questions arising from genetic testing and uncertainty about the impact of specific or multiple mutations. Rather than spending time on getting to grips with the mutation, researchers can cut to the chase of finding simply what works.

Despite the apparent success of the study, the inevitable note of caution was sounded – not all biopsies yield cells amenable to growing in a laboratory. And even when they do, cells may take up to six months to develop. As Engelman points out, “patients really need to know how to treat their cancers as soon as possible”. Furthermore, this approach has not yet been used on people.

Several companies now offer the possibility of transplanting tumours from patients into mice to test treatments. However, Engelmann argues cell cultures could ultimately offer the advantages of speed and versatility over transplantation when it comes to large drug screens.

The team at Massachusetts is now working to reduce the culture time to a matter of weeks.