Breast cancer spreads most while the patient is asleep, new studies suggest.
Researchers say the findings could significantly change the way cancer is diagnosed and treated in the future.
They may also indicate that doctors need to record the time when a cancer biopsy is done, as their study can also affect the number of cancer cells detected. I add.
According to the World Health Organization (WHO), breast cancer is one of the most common cancers, affecting about 2.3 million people worldwide each year.
Researchers say that if the disease is detected early enough, patients will respond well to normal treatment.
But if the cancer has already spread, things will be much more difficult – it will spread to other parts of the body.
Metastasis occurs when circulating cancer cells move away from the original tumor, move through the body through blood vessels, and form new tumors in other organs.
A new study by researchers at ETH Zurich, the University of Basel Hospital, and the University of Basel found that circulating tumor cells, which later form metastases, occur primarily while people are asleep.
Nicola Aceto, a research leader and professor of molecular oncology at ETH Zurich in Switzerland, said: “The tumor awakens when the affected person is asleep.”
“Our study shows that the escape of circulating cancer cells from the original tumor is regulated by hormones such as melatonin that determine the day-night rhythm,” said the lead author of the study. , ETH Zurich postdoctoral fellow Zoi Diamantopoulou added.
The study included 30 female cancer patients and a mouse model, and researchers found that tumors produced more circulating cells during sleep.
According to researchers, cells that leave the tumor at night are also more likely to divide faster and thus form metastases than circulating cells that leave the tumor during the day.
Scientists were also surprised to find that the levels of circulating cancer cells in samples taken at different times of the day were very different.
Another clue was the higher number of cancer cells found per unit of blood in mice compared to humans.
As a nocturnal animal, mice sleep during the day. That’s when scientists collect most of their samples.
Professor Aceto said: “In our view, these findings may indicate that healthcare professionals need to systematically record the time it takes to perform a biopsy.
“It may help make the data truly comparable.”
The following researchers hope to establish how these findings can be incorporated into existing cancer treatments to optimize treatment.
The findings are published in the Nature Journal.