Nikolay Goncharov, a post-graduate student at Far Eastern Federal University (FEFU), designed a new test system for determining chromosome instability in cells, in collaboration with a group of researchers of the National Institutes of Health, U.S. Department of Health & Human Services, where he completed an internship. Visual proof of this technology was obtained at the Biomedical Cell Technologies Laboratory, FEFU School of Biomedicine.
As explained by Nikolay Goncharov, all cells have a certain set of chromosomes: humans have 46 of them. Their abnormalities for any reason lead to various disorders and diseases. For example, a set of chromosomes in cancer cells is very often unstable, that is, mutations occur in genes that lead to the loss of chromosomes.
In the new test system, the FEFU post-graduate student uses quite rare, yet elegant method of searching for genes responsible for chromosome instability—an artificial human chromosome. Only five laboratories in the world work with such ones. According to Nikolay Goncharov, for many years the artificial chromosome has been designed by the Russian scientists, who now are working at the National Cancer Institute, National Institutes of Health (USA): Vladimir Larionov and Natalia Kuprina. It was under their supervision that the FEFU post-graduate student had already undergone three long-term internships, during which the promising cellular technology appeared.
"The test system is a line of human cancer cells, where an artificial chromosome is built into," said Nikolay Goncharov. "It is marked with a green fluorescent protein, which highlights the cells with an extra chromosome. If we affect this cell line with something that causes chromosome instability, such as anti-tumor drug, we see that the cells lose their luminescence after some time. Since the artificial chromosome is unstable, it is lost first of all.
According to Nikolay Goncharov, the test systems may be used, for example, for testing the effect of antitumor drugs and, in the long run, to find candidates for the role of new drugs. But the other side of its use is more interesting for the young scientist.
"With the help of the system one can search for genes that are important for mitosis, i.e. cell fission. This process is controlled by a huge number of genes, and in humans they have been studied less, for example, than in bread yeast. There are 642 of them known in yeast, and only 200 ones in humans. They cannot be less than those in yeast, so the missing ones need to be searched for," explained the post-graduate student. "We carried out such search and have already found orthologs of yeast genes in the human genome, whose function in human cells has not been determined yet. Now, with the help of the test system we disable the found genes one after another and monitor the loss of chromosomes. If the cell loses the green signal, thus disabling this gene causes chromosome instability."
It is worth noting that it was the Biomedical Cell Technologies Laboratory, FEFU School of Biomedicine, where they managed to demonstrate the principle of the system's operation. That became possible by monitoring cell fission with the Olympus Confocal Laser Scanning Microscope in the FEFU Common Use Center.
The results of the study, which the young FEFU researcher carries out as a part of the international group, were published in top rated scientific journal Oncotarget. The scientific supervisor of the post-graduate student's work is Vadim Kumeyko, Deputy Director for Development, School of Biomedicine.