VT Biologists Find Cancer Connection to Our Body Clock

Feb 15, 2019

A new discovery finds that timing is everything when it comes to preventing and treating cancer. Scientists at Virginia Tech are the first to confirm the important role our bodies' internal clocks play in whether we are more prone to develop the disease.

After you wake up in the morning, you might think it’s your coffee that perks you up, but molecular biologist Carla Finkielstein says, "That’s not it at all.  It’s actually a placebo. That coffee may make you feel good but it is not doing anything” to wake you up in the morning.

That role is played by our circadian rhythms, says Finkielstein, our pre-set ‘body clock’ that never varies, even if our own schedules do.  And here’s how it rules:  Finkielstein says 8:30 a.m. is THE time when humans are ready to roll. Peak alertness hits at 10:00 a.m., and prak time for physical activity is 5 in the afternoon.  Deep sleep comes at 2 in the morning. 

Mess with that internal clock and you could trigger disease. 

Carla Finkielstein and Xianlin Zou compare notes in the laboratory.
Credit Virginia Tech

“Actually, we humans are responsible for rearranging our clocks and causing most of the diseases we suffer today in western societies.” Says Finkielstein.

Her team’s new research confirms her earlier findings that, this is why night shift workers develop cancer at a higher rate. The bright light they’re exposed to at night confuses cancer suppressing molecules and cancer fueling oncogenes. Finkielstein says, programs limiting how long people stay on that night shift, could help. 

The study also finds that the timing of a cancer drug could make all the difference.  For example, it may be best to give cancer drugs during the day. That’s when cells are dividing, due to that internal body clock.  In cancer, you want to slow down the cells’ divisions, so attacking them while they’re active is most effective.

Finkielstein says, “In the past we’ve given people cancer drugs at night.”  That’s because the side effects are not pleasant, so it’s better that people sleep through it.  But it turns out that doctors actually have to use larger doses to be effective when the medicine is given at night.  It may not be as potent in the morning, when the body tells those cells to grow.

But here’s the problem we face in beating the clock; practically no one these days can live perfectly by hewing to our hard-wired circadian rhythms, getting up the moment the sun rises and going to sleep as soon as it sets. So, what can you do in this day and age? Finkielstein says, limiting bright light at night, dimming down your devices with programs you can find online and set for ‘night,’ and/or wearing blue light blocking glasses, could help keep our circadian rhythms from getting out of tune and setting us up for disease. 

Their paper on this topic appears in the journal Science Signaling.

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