Repair of the "guardian of the genome"

Biologists have learned how to repair the cancer protection system in tumor cells

RIA NewsAmerican biologists have learned how to correct damaged molecules of the p53 protein in cancer cells, which protects healthy cells from the appearance of fatal mutations in DNA, which will quickly and practically guarantee to rid patients of some forms of cancer in the near future, according to an article published in the journal Nature Communications (Wassman et al., Computational identification of a transiently open L1/S3 pocket for reactivation of mutant p53, in the public domain – VM).

A significant part of cancerous tumors in humans and other animals occurs due to a breakdown in the p53 gene. It is responsible for protein synthesis, which monitors the integrity of genetic information and includes a self–destruction mechanism – apoptosis - in case of serious violations in the DNA structure. Therefore, cell cultures with a damaged p53 gene are extremely difficult to destroy due to the lack of a "self-destruction program" in their genome.

A group of geneticists led by Peter Kaiser from the University of California at Irvine (USA) has learned to repair damaged p53 molecules present in more than a third of the known types of cancer tumors by studying the structure of mutations in the protein body.

The authors of the article found that mutant protein molecules can be made to work normally if a certain substance is attached to one of its parts – the so-called "pocket" L1/S3. It is a small depression in the three-dimensional structure of p53, which plays a critical role in triggering apoptosis, and even single amino acid substitutions inside L1/S3 lead to protein breakdown.

As Kaiser and his colleagues found out, some of these damages can be repaired with the help of the so–called stictic acid - "gluing" of two benzene rings, as well as several "tails" of oxygen and hydrogen atoms. This substance is embedded in the damaged pocket and makes the p53 protein "compatible" with other components of the cell's self-destruction system.

The researchers tested the work of this compound on several cultures of "immortal" cells, including a sample of bone cancer. According to biologists, the addition of stictic acid slowed the growth of crops and in some cases led to their reduction. Further study of the "pocket" of L1/S3 and acid will help to find treatments for several types of cancer at once, the authors conclude.

Portal "Eternal youth" http://vechnayamolodost.ru30.01.2013