Two - faced squirrel
Biologists from Moscow State University have revealed the secrets of the protein-the "helper" of cancer
Russian molecular biologists and their colleagues from Sweden have found out how one of the main "proteins of life" works, which cancer cells use to disable cellular self-destruction systems. Possible medical applications of this discovery were presented in the journal Trends in Cell Biology (Senichkin et al., Molecular Comprehension of Mcl-1: From Gene Structure to Cancer Therapy).
"In our laboratory, we are trying to understand what substances tumor cells die from, but we are also looking for an answer to the question why tumor cells die from one substance, but do not die from another," says Vyacheslav Senichkin, an employee of the Faculty of Fundamental Medicine of Moscow State University.
Scientists from MSU have been studying the protein and the Mcl-1 gene of the same name for many years, associated with the operation of the self-destruction system present in all healthy and in many cancer cells. This system consists of several dozen protein molecules, some of which cause the cell to start apoptosis, the process of cellular suicide, while others, on the contrary, suppress it.
In healthy cells, there is a kind of balance between "death proteins" and Mcl-1 and other similar molecules that suppress their work. When cancer occurs, this balance shifts towards Mcl-1 and other "life proteins", so that tumor cells do not die even with very serious DNA damage, which usually causes cells to kill themselves.
Guided by this idea, two years ago Russian scientists created several retroviruses, some of which increased the activity of Mcl-1, while others blocked its work. As these experiments showed, cancer cells with an "improved" version of this protein resisted chemotherapy better and died less when exposed to radiation, and the suppression of the associated gene, on the contrary, made them extremely vulnerable to their actions.
These discoveries and the successes of other scientific groups forced Russian scientists working under the leadership of Boris Zhivotovsky, a professor at Moscow State University and the Karolinska Institute, to collect and systematize all the results of such experiments. This allowed biologists to identify the most effective ways to suppress Mcl-1 in cancer cells without harm to the rest of the body, as well as to reveal the mechanism of functioning of this "protein of life".
Scientists, in particular, were interested in why this substance in some cases accelerates apoptosis, and in other cases it suppresses it. Analysis of more than a hundred scientific papers showed that this was due to the fact that the cell can synthesize several different forms of Mcl-1, one of which blocks apoptosis, and the other, on the contrary, accelerates it.
Other features of this protein, in particular, its short life span inside cells, make it possible to destroy its molecules in a variety of ways, directly connecting to Mcl-1 or destroying its chains, as well as forcing cells to "starve" and spend less resources on assembling short-lived peptides. Some drugs of this kind are already undergoing or are being prepared for clinical trials.
"Now we are actively studying how Mcl-1 blockers affect different tumor cell lines. This is how we systematize all knowledge and improve approaches aimed at neutralizing Mcl-1 in tumors," concludes Zhivotovsky.
Portal "Eternal youth" http://vechnayamolodost.ru