An analysis of thousands of tumors from NHS patients has identified a “treasure trove” of new evidence for the causes of cancer.
In the largest study of its kind, researchers at Cambridge University Hospital looked at the genomes of more than 12,000 people with cancer in England.
They noticed 58 new patterns in their DNA, called mutation signatures, suggesting there are reasons why scientists are not yet aware.
The researchers hope the discovery will allow future research to uncover the root of these cancer-causing mutations.
Scientists knew of only 51 mutation signatures before the new discovery, including changes caused by smoking or UV light.
Identifying these signatures also allows physicians to examine each patient’s tumor and compare it to specific treatments and medications.
However, models can only be found in cancer patients whose entire genome has been sequenced by scientists – which is not routinely done.
Professor Serena Nick-Zainal, the genome expert who led the study, said the models were “fingerprints at the crime scene”.
She said the findings could indicate an “Achilles’ heel” in some cancers that could be treated.
Researchers at the University of Cambridge have studied the genetic makeup of more than 12,000 people with cancer in England, which allows them to see the origin of the tumor. They found 58 new models in cancer DNA, suggesting there are reasons why scientists are not yet aware
HOW DOES CANCER DEVELOP?
Cancer begins in the cells.
Inside almost every cell in the body is a copy of your genome made from DNA.
The genome can be considered as instructions for the operation of a cell. He tells the cell what kind of cell it should be – like a skin cell or a liver cell – and has instructions that tell the cell when to grow, divide and die.
When one cell divides to become two cells, the genome is copied. This usually happens in a controlled way and is the way bodies grow and recover.
But sometimes mistakes are made in copying the genome. These are called mutations.
Errors can be caused by natural processes in the cells, accidentally or by external factors such as UV light or smoking.
Most damage is repaired immediately without negative consequences.
But sometimes mutations in critical genes mean that he no longer understands his instructions and reproduces out of control.
The abnormal cell continues to divide and produce more and more abnormal cells. These cells form a lump called a tumor.
Source: Genomics England
About 375,000 new cancers are diagnosed in the United Kingdom each year, while 1.7 million are confirmed in the United States.
Cancer is caused by mutations in the genome of cells, which causes cells to multiply out of control while forming a tumor.
The latest study, published in the journal Science, analyzes the entire genome of 12,222 NHS cancer patients as part of the 100,000 Genome Project in England.
Genomic sequencing examines all the thousands of building blocks of DNA in each tumor, showing mutations that contribute to each person’s cancer.
Some of the new mutation patterns observed are present in many different cancer patients, while some are less common.
Cancer is thought to have a limited number of mutational processes, which fuels the search to identify all of them and what causes them.
Knowing that the signatures are present in the tumor helps to understand the root cause of them and to indicate whether the mutation is caused by environmental factors or a genetic problem.
Professor Nick-Zainal told MailOnline: “Sometimes I use the analogy of fingerprints in the sand, where mutational signatures are fingerprints.
“When you look across the beach, there can be fingerprints everywhere (similar to cancer, mutations seem a bit random, they are everywhere).
“But if you study the prints in detail, there are characteristics that tell you whether the prints are animal or human.”
She added: “Mutational signatures are like these fingerprints. We can begin to understand whether something is due to external or cellular factors by studying mutation patterns in detail.
The researchers used their findings to develop an algorithm called Signature Fit Multi-Step (FitMS), which can detect mutational signatures in new samples of the cancer genome.
Only patients who have had their entire cancer genome sequenced will be able to benefit from the tool, but the team believes it could be spread “very quickly.”
Currently, only childhood cancers, specific leukemias and sarcomas – rare cancers affecting body tissues – are sequenced by the NHS, but experts expect the list to be expanded in the coming years.
FitMS will notice mutational signatures in these patients’ cancer, which the researchers hope will accelerate their ability to compare them to more specific treatments.
Professor Nick-Zainal said: “The reason it’s important to identify mutational signatures is because they’re like fingerprints at a crime scene – they help identify those responsible for cancer.
“Some mutational signatures have clinical or therapeutic consequences – they may highlight abnormalities that may be targeted by specific drugs or may indicate a potential ‘Achilles’ heel’ in certain cancers.”
Michelle Mitchell, CEO of Cancer Research UK, said: “This study shows how powerful whole-genome sequencing tests can be to provide clues as to how cancer may have developed, how it will behave and what the possibilities are. for treatment would work best.
The results could “potentially be used within the NHS to improve the treatment and care of people with cancer,” she added.
Professor Matt Brown, chief research officer at Genomics England, said applying mutational evidence to patients “could improve the diagnosis and treatment of cancer patients”.
Add Comment