Glowing report: firefly gene shows hidden leukaemia cells

16 Feb 2017

A test that makes drug-resistant leukaemia cells glow could reveal a brighter future for developing new leukaemia therapies.

A new method for finding hidden leukaemia cells by making them glow was investigated by Dr Luke Jones, and the results published in the journal Clinical Cancer Research. It offers a more sensitive and accurate preclinical test for leukaemia drugs, increasing the chances of finding those most likely to succeed in clinical trials.

Childhood leukaemia has survival rates of approximately 90% but some subtypes, and relapsed leukaemias, have very low survival rates. Identifying new agents to test is a focus of our Leukaemia Biology Program. The team has an international role in preclinical drug testing for paediatric leukaemia. Luke’s research into a new preclinical test is based on making leukaemia cells glow to reveal reservoirs of the disease. He’s excited by its potential.

“Bioluminescence imaging can more accurately measure drugs’ effects on high risk leukaemias that are either unresponsive to standard treatments or likely to relapse.”

“Using information from bioluminescence imaging will help make sure only future drugs with the best chance of success go on to be tested on human patients in clinical trials”, he explained.

Testing potential new leukaemia drugs

Before new drugs can be given to children, their safety and effectiveness is tested in mouse avatars that model different leukaemia subtypes. Each drug’s effectiveness against these models is typically monitored by measuring the amount of leukaemia cells in the blood. However the blood is one of the last places the leukaemia spreads to, and the first place it’s eliminated from with treatment. So cancer cells could be hiding away in organs like the spleen or bone marrow even if all leukaemia cells have been cleared from the blood. But how to find these hidden cancer cells?

Bioluminescence imaging to track cancer cells

Fireflies flying around in the forest at night (image: istock)

In nature, bioluminescence is the light given off by animals like glow-worms, fireflies, jellyfish and some deep-sea fish. In 2015, for example, blooms of single-celled animals called dinoflagellates treated Hobart residents to a sensational light show at local beaches.

To make leukaemia cells bioluminescent, scientists cloned into their DNA the gene that makes fireflies glow. This means a scan can show any hidden ‘reservoirs’ of leukaemia. Bioluminescence imaging is non-invasive and offers researchers sensitive monitoring of leukaemia burden over time.

Bioluminescent materials from nature can be used the lab

A new preclinical test

Luke’s research is the first time bioluminescence imaging has been compared to traditional methods of assessing preclinical drug efficacy in an effort to increase our ability to predict clinical success. It is also the first time bioluminescence imaging has been evaluated for its ability to track the amount of residual disease following treatment in a preclinical leukaemia model.

“Our paper shows that bioluminescence imaging gives us extra stringency”, said Luke.

“It gives us more and better information to make decisions about which drugs to progress to clinical trials.”

Read the research paper published in the journal Clinical Cancer Research.

Top image: Dr Luke Jones with scans showing leukaemia cells