Vanesa Lopez
02/09/2020 - 15:17
Clarín.com
Society
A study published in the scientific journal
Nature
provides strong evidence that cancer continually reshapes its genome on a large scale and that changes continue
throughout the life
of the tumor.
The finding was prevalent in 22 types of tumors, including breast cancer, colorectal cancer, and lung cancer.
And both the authors of the report and Argentine experts consulted by
Clarín
agree that the results could contribute to
future treatment approaches.
Researchers from the Max Delbrück Center (Germany), the Francis Crick Institute (England) and University College London (England) addressed
an ongoing debate
in the field of cancer genomics.
Some scientists argue that there are a number of evolutionary changes early in a tumor's life, but then the genome remains relatively stable.
Others - like the authors of this study - suspect that these changes
they continue
throughout the life
of the cancer.
"Our approach provides substantial evidence of
ongoing
chromosomal instability
with a level of detail that was previously impossible," said Roland Schwarz, one of the leaders of the work.
The genome study was done on 22 different types of cancer, including breast cancer.
"The amount of ongoing structural evolution of these cancer genomes
is much higher
than we originally anticipated, and higher than the community generally suggests," Schwarz added.
Scientists worked for the past five years to develop a method that could help clarify these
large-scale mutations in great
detail.
"Understanding the amount of ongoing chromosome instability and the resulting copy number heterogeneity could provide
future treatment approaches,
" said lead study author Tom Watkins.
“There are arrangements of genes that are produced with the same division of the cell, which cannot repair them, and
they accumulate and generate cancer
.
That is a finding that this year had already been offered in this way, ”says Santiago Bella, vice president of the Argentine Association of Clinical Oncology (AAOC).
“It is very relevant because in reality those genes seem to be very limited, they seem to be approximately 300.
And if we could find a way to correct them or correct their actions, that would be a way forward in
managing the disease better
”, continues the oncologist.
Dr. María Marcela Barrio, researcher of the scientific program of CONICET and the SALES Foundation, CIO - FUCA, agrees that "
the finding is very interesting
", since it provides evidence in favor of the hypothesis of continuous tumor evolution, possibly remodeling with the selection of cells that 'adapt' to survive, replicate and spread better.
The experts found that the amount of ongoing structural evolution of these cancer genomes is much higher than previously thought.
According to the expert, tumor cells require, to adapt, changes in many genes.
Furthermore, the fact that the observed genetic changes occur in cells of some portion of the tumor in one way and in another in another, would contribute to understanding the heterogeneity observed in tumor biopsies.
"For decades we have observed such cellular heterogeneity, which contributes to making the approach to cancer research and treatment more complex. The present discovery
helps us understand the dynamics
that would generate it," says Barrio.
And he emphasizes: "What is unexpected and surprising is that
such large chromosomal portions
are involved
, which contain many genes, in turn increasing the diversity within the tumor."
Regarding the specific applications that the finding could have in cancer therapeutics, Bella comments: “If we manage to correct the product of those genes - which are the proteins that give it function and facilitate cell growth - one could go on to correct these phenomena
so that the tumor stops growing
”.
According to Barrio, analyzing which genes are being lost or gained, depending on the evolution of the tumor, will allow the discovery of new target genes for the
development of targeted therapies
, as well as their association with resistance to antineoplastic drugs and immunotherapy.
European researchers are currently testing their novel algorithm - called "refphase" - for public release as open access software for data analysis.
This will allow others in the field to use your technique.
ACE
