After a 13-year study, US researchers have discovered a specific pattern of change in the length of a biomarker found in cells, which happens many years before a patient starts suffering symptoms of cancer.
A team formed by scientists from Harvard and Northwestern analyzed 792 initially cancer-free people in the period, in which 135 were eventually diagnosed with different forms of the illness. In those 13 years, the researchers constantly monitored their telomeres.
Telomeres are protective caps which lay on the ends of chromosomes. As people grow older, and their cells are replicated more and more times, the telomeres are getting shorter, and eventually the cell cannot be replicated again, and it dies. The protective caps can be more than an indicator of ageing, but also its cause, as cells with worn-out telomeres can present many faults and cause a range of diseases.
The people who were diagnosed with cancer had suffered an alarming drop in telomeres many years before the disease developed. Some future patients had telomeres which are usually found in persons which were 15 years older.
The scientists also discovered that three to four years before the diagnosis, the shrinking would stop, and levels of telomeres would stabilize, but this was not considered to be good news at all.
“We found cancer has hijacked the telomere shortening in order to flourish in the body,” said Dr. Lifang Hou, a professor of preventive medicine at Northwestern University Feinberg School of Medicine, and the lead author of the study, which has just been published in EBioMedicine magazine.
Under normal condition, a cell with a shortening telomere might be old, but it would then self-destruct in order to prevent any of cell abnormalities to spread through the body. In the case of future patients, these cells did the opposite – they multiplied. They achieved this with the help of the enzyme telomerase, which is actively contributing to the development of cancer.
“Understanding this pattern of telomere growth may mean it can be a predictive biomarker for cancer. Because we saw a strong relationship in the pattern across a wide variety of cancers, with the right testing these procedures could be used to eventually diagnose a wide variety of cancers,” explained Hou.
Scientists are now waging two separate medical wars. The first is to slow down the telomere shrinking, while the other is to set up a potential cancer treatment that would cause the afflicted cells to self-destruct instead of multiplying.
According to the World Health Organisation data, there were more than 14 million new cancer diagnoses in 2012, the year of the most recent statistics. In the same year, more than 8 million people died of the disease.
Image Source: The Telegraph