Live monitoring of individual cancer cells can greatly benefit the search for drugs that target tumors. Researchers from the Singapore Institute for Clinical Sciences and Methodist Hospital of Cornell University transferred a gene from a firefly into cells of glioblastoma multiforme (GBM) to make it bioluminesce in zebrafish.
They assessed the ‘invasiveness’ of the cells by measuring how quickly they moved through a three-dimensional matrix, and found that the most invasive cells express a gene that makes them more mobile. The same gene has also been correlated previously with reduced patient survival.
The researchers then injected the GBM cells into zebrafish embryos, and observed tumors in the embryos a few days later. By placing the embryos under a charge-coupled device camera, they were able to watch the bioluminescent tumor cells growing and moving around the body, invading other organs.
This new bioluminescence screening platform represents a unique real-time method for observing small numbers of cancer cells in a live animal. It is cheaper, easier and far more sensitive than existing imaging methods such as positron emission or computed tomography scanning, or magnetic resonance or fluorescent imaging. Furthermore, the discovery of a genetic subset of highly invasive GBM cells could help greatly in the development of drugs that target tumor-initiating cells.
The team plans to use the platform to screen anti-migration and invasion candidate compounds for GBM treatment and extend the platform for drug screening in other invasive tumors and for drug combination studies.
Press release: Bioimaging: Keeping an eye on cancer…
Abstract in Journal of Neurosurgery: A screening platform for glioma growth and invasion using bioluminescence imaging