Pancreatic cancer cells may have disrupted internal clocks that help to drive their spread. The discovery could pave the way for novel treatments for the condition, .
Nearly every cell in our body contains molecular clocks that allow them to carry out biological processes in regular 24-hour cycles, known as circadian rhythms. These clocks are partly set by changes in light across days and nights.
Previous studies found that , because their growth is no longer tightly regulated.
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To find out if this plays a role in pancreatic cancer development, at the University of Wisconsin-Madison and his colleagues studied the expression of several genes involved in cellular timekeeping in cancerous and non-cancerous pancreatic tissue collected from 72 mice and more than 300 people.
In healthy pancreatic tissue, the expression of these clock genes followed regular 24-hour patterns, but in pancreatic cancer, these rhythms were lost, both in mice and people.
Next, the researchers genetically engineered pancreatic cancer cells to knock out an important clock gene called Bmal1.
When mice were injected with these modified cancer cells, the cells grew faster, spread sooner, showed greater resistance to chemotherapy and resulted in earlier animal death, compared with injecting mice with unmodified pancreatic cancer cells.
The results suggest that circadian disruptions drive pancreatic cancer, which is consistent with other studies showing that cancers of the , , and also contain disrupted circadian clocks, says Ronnekleiv-Kelly.
One reason why cells may lose their ability to tell the time is if a person鈥檚 natural circadian rhythms get out of sync due to irregular sleep patterns or prolonged exposure to artificial light, says at the聽Salk Institute聽in California.
Studies have found that people who do shift work, for example, are more likely to develop a range of cancers, .
Panda and his colleagues have developed drug candidates that can reactivate cells鈥� circadian clocks, . Such drugs may also help to treat pancreatic cancer, he says, but research into this is required.
Individuals could reduce their cancer risk by having regular sleep patterns and eating all meals within an 8 to 10-hour window during the day, known as time-restricted eating, to 鈥渞einforce the circadian clock鈥�, says Panda.
As well as light exposure, our meal timings also affect our circadian rhythms, implementing time-restricted eating.
搁别蹿别谤别苍肠别:听bioRxiv,
