Will scorpion venom help fight cancer?

"Scorpion venom could prove to be a revolutionary new weapon in the war against cancer," the Daily Express reported on July 16 2007. Four newspapers and the BBC reported that researchers have developed a "glowing paint" derived from scorpion venom which can help detect microscopic levels of the disease.

The Daily Mail reported that applying the paint to a suspect area, would make it easier for surgeons to distinguish between tumours and healthy tissue and enable them to remove every bit of cancer.

The Daily Express stated that the paint is 500 times more sensitive than an MRI scanner at detecting tumours. An MRI scan can only detect cancerous cells when they number over a million cells and the paint can spot just a few hundred malignant cells. 

The stories may give the impression that when applied to tumours, the substance can distinguish cancer from healthy tissue and that a product could be on the market within 18 months.

The NHS Knowledge Service considers this a preliminary experimental animal study testing a novel and potentially exciting technique. The safety and practicality will need much more evaluation and testing before it could be of use on the operating table.

Where did the story come from?

This study was conducted by Mandana Veiseh and colleagues from the Fred Hutchinson Cancer research centre in Seattle, and published as a research article in the peer-reviewed journal Cancer Research .

What kind of scientific study was this?

The original research on which these headlines were based was performed in genetically engineered mice and is a pre-clinical evaluation of a molecular imaging technique.

A molecule that glows under blue light was attached to a protein found in scorpion venom. The protein is known to attach itself to certain types of brain cancer, and this was used to make a cancer cell-specific "paint". 

As part of the study, mice that had been genetically engineered to develop tumours were injected with the paint. The uptake of the paint or probe was assessed by a technique known as biophotonic imaging, in which the probe was detected by its fluorescent reaction to light.

What were the results of the study?

The researchers found that the probe attached to tumour cells in the brain, prostate, intestine, and bone in the mice, in preference to the normal cells in the surrounding tissue. This meant that the researchers could identify the tumours easily.

What interpretation did the researchers draw from these results?

The researchers conclude that these studies show that their technique has the potential to fundamentally improve the detection and removal of cancers during surgery.

What does the NHS Knowledge Service make of this study?

The authors correctly alert us to the fact that many more safety and effectiveness trials will be required before this technique could be applied to humans.

This is a preliminary experimental animal study testing a novel and potentially exciting technique. The safety and practicality will need much more evaluation before it could be of use on the operating table.