Many things go wrong in a person's biology when they have cancer. Their genes could mutate or experience dramatic molecular changes, and their cells proliferate too much that it forms new tissues called tumors.
Cancer research mainly focuses on the genome to understand what happens at that level of their DNA and perhaps someday scientists could find a way to prevent cancers.
According to EurekAlert!, researchers from the University of Lausanne (UIL) and EPFL have recently made a breakthrough in discovering a crucial genetic aberration that happens in cancer cells.
Together with other researchers, they used algorithms to study how cancer cells reorganize their DNA's 3D structure that increases the activity of oncogenes, the gene that promotes cancer.
Chromatin Condenses Into Chromosomes
Researchers looked at how chromosomes are organized in the tight space of a cell nucleus. Each cell contains at least two meters of DNA that are stored properly due to the evolved mechanisms of the cells, the science news outlet reported.
These mechanisms involve looping DNA around special proteins called histones that form the DNA-protein complex called chromatin.
Several chromatins make up the structure of chromosomes in cells. Typically, there are two copies of each 23 chromosomes but cancer cells reorganize this structure and cause change. For instance, a copy of chromosome 8 could attach to a copy of chromosome 14.
Furthermore, chemical modifications known as epigenetic marks could influence whether a chromosome could take on a more relaxed or compact structure. Researchers explored how changes in these epigenetic marks reorganize chromosome structures and the gene expression that ramp up oncogene activity.
Epigenetic Changes Lead to Reorganization Chromatin Regions
UNIL researchers led by Giovanni Ciriello developed a new algorithm named after American sculptor Alexander Calder to track how genomic regions are placed in the nucleus.
"We used Calder to compare the spatial organization of the genome in more than a hundred samples. But this organization is not static and, just like Alexander Calder's mobile sculptures, it can rearrange its pieces," Ciriello said.
Scientists used Calder to determine the regions that chromatins moved from one area inside the nucleus to another because of the changes that occurred in epigenetic marks. They have recorded these changes in normal and B-cell lymphoma cells, according to Tech Explorist.
Researchers found that epigenetic changes, especially in lymphoma cells could change the positions of chromatin regions in various areas within the nucleus that promote interactions that over-activate oncogenes.
Moreover, researchers found that two fragments from different chromosomes are damaged and swapped, assuming a 3D structure different from the normal copies that correspond to the different epigenetic marks that give rise to the expressions of genes that promote the growth of tumor cells.
"Most of the time, we think of our DNA as a long, linear molecule, and it's only recently that we started to understand how its 3D organization is altered in cancer cells," Elisa Oricchio from EPFL said.
"Considering the spatial organization of DNA in the nucleus provides a new lens to understand how tumor cells originate, and how therapeutic modulation of epigenetic marks can block tumor progression."
RELATED ARTICLE : Cancer Cells Also Hibernate Like Bears to Survive Chemotherapy
Check out more news and information on Cancer Cells on Science Times.
