MOSCOW, May 25. /TASS/. Researchers from the Moscow Institute of Physics and Technology (MIPT), the Engelhardt Institute of Molecular Biology (EIMB RAS), the Institute of Bioorganic Chemistry (IBCh) and a number of other Russian research centers have developed a new method of diagnosing colorectal cancer.
The scientists have created a hydrogel-based biochip to help detect bowel cancer i.e. colorectal cancer (CRC).
"The method developed at EIMB RAS has great potential to be used in diagnosing gastrointestinal diseases. We hope that testing systems based on the method will soon appear in clinical laboratories in Russia," said Zhanna Zubtsova, one of the developers of the new method, Ph.D. in Physics and Mathematics, assistant professor at MIPT.
CRC is the third most common type of cancer and it develops with minimal clinical symptoms in the early stages. Despite doctors’ efforts, the 5-year survival rate does not exceed 36% Diagnostic methods that are currently in use are not sufficient. Analyses carried out in vitro have low specificity and invasive studies such as colonoscopy are not only traumatic, but they are also not always suitable for an early diagnosis, as they do not give a complete picture of the development and distribution of colorectal cancer.
To increase diagnostic sensitivity, researchers turned to glycobiology, a rapidly developing science that is focused on the most important biological molecules - glycans. Tumor cells have special glycans enabling scientists to differentiate them from healthy cells, and this is the key aspect of the new study. To detect tumor-associated glycans, scientists use autoantibodies. Antibodies are molecules produced by the immune system to attack enemy cells with high precision.
The researchers proposed looking for autoantibodies against tumor-associated glycans in serum with biological microchips used as the primary diagnostic tools. A microchip is normally a flat plate containing samples of particular biological molecules. The researchers developed a model of the test-system which is able to simultaneously measure the concentration of protein-based oncomarkers, the autoantibodies-to-glycans ratio, and immunoglobulins IgG, IgA, and IgM in a patient’s blood. Using the model, the scientists analyzed the sera of 33 patients with colorectal cancer, 69 healthy donors and 27 patients with inflammatory bowel disease.
The model of the test-system based on diagnostic signatures was able to diagnose CRC in 95% of cases, compared to 79% detected by traditional methods. The sensitivity of CRC detection was 87% versus 21%. This increase is clearly a significant achievement. The specificity of the method is 97%. The sensitivity of 87% tells us that the method will detect CRC in 87 out of 100 cases of patients with the disease. The traditional method of detecting CRC has a sensitivity of 21%, which means that a number of patients with CRC will be declared healthy. In patients with inflammatory bowel disease, cancer will be correctly diagnosed in 97% of cases.
The results of the study have been published in Cancer Medicine.