Jul 04, 2011
Detecting cancer may be possible with a simple blood or urine test in the near future. Traces of tumoural DNA in the biological fluids of patients suffering from cancer can now be detected by a newly developed technique. It involves ultra-sensitive analyses carried out on microscopic droplets of biological fluids. This work is expected to help in becoming a powerful tool for the diagnosis and treatment of various cancer types.
The successful testing on genes of various cancers such as colon cancer and leukaemia has the potential of becoming the basis for a powerful tool in the hands of oncologists. When cells with tumoural DNA die, their content is spilled on to the extracellular medium. These contents which include the DNA of cells find their way to the biological fluids such as lymph, urine, etc. As most of the cancer development has some genetic factor in its cause, detecting the tumoural DNA in the biological fluids can help to diagnose cancer early. As soon as the first cancerous cells die, which happens at a very early stage, the blood or urine can be tested for presence of tumoural DNA.
The project of developing a testing technique for tumoural DNA was undertaken by three organisations, CNRS, Inserm, Paris Descartes and Strasbourg Universities. The expertise of biologists and researchers from three institutes was needed because conventional DNA testing methods cannot detect cancerous development. Less than 0.01 % of total DNA is comprised of the particular tunoural DNA. These institutes have developed a technique which makes it possible to detect DNA thresholds 20,000 times lower than the usual clinic components can detect.
This technique has been successfully used for isolating and identifying a gene that can cause colon, pancreas or lung cancer. The DNA in question was derived from cell lines of the laboratory. This method remains to be tested for therapeutic purposes. With a clinical study already scheduled, physicians can soon have a weapon against cancer for diagnosis and treatment.
The possible areas in which this study is expected to help are identifying the aggressiveness of cancer, how it will respond to current treatments and the risks involved in local treatment. These information can be extracted from the tumoural DNA.
The aggressiveness of the cancer, its responsiveness to existing treatments and its risk of recurrence following local treatment: all this information is partly contained in the tumoral DNA. Suitable therapeutic strategy can be determined with such insights on the cancer causing genes.