How Your Lack of Sleep can Help Tumors Thrive

Lack of oxygen, or hypoxia, caused by sleep apnea could lead to tumor growth, study from Barcelona, Spain finds.


Getting a good night's sleep could be a lifesaver for those with cancer.

According to a new study from Hospital Clínic De Barcelona in Spain, University of Chicago and Memorial Sloan-Kettering Cancer Center in New York City, sleep apnea could contribute to the growth of blood vessels inside tumors.

Sleep apnea is a condition marked by shallow breaths or pauses in breathing during sleep. The pauses can last from seconds to minutes and sometimes occur 30 times an hour. According to the National Heart, Lung, and Blood Institute, most daytime sleepiness is a result of sleep apnea.

In this study, which was presented at the European Association of Urology Congress in Munich, Germany, researchers focused on another consequence of sleep apnea: hypoxia. Hypoxia is when the organs and tissues are receiving insufficient oxygen. This hypoxia could be contributing to the growth of blood vessels inside of tumors, the researchers said.

"This work shows that intermittent hypoxia has the potential to promote the formation of blood vessels within tumors, meaning that the tumors have access to more nutrients," lead researcher Dr. Antoni Vilaseca said in a press release.

Dr. Vilaseca and team, who used mice for this study, found that with decreased oxygen, a mechanism called vascular endothelial growth factor (VEGF) activated to help tumors thrive. VEGF is a survival mechanism that encourages the growth of blood vessels when the body's tissues are not getting enough oxygen, according to the University of Rochester Medical Center in New York (which was not involved in the study). VEGF is especially important to the lungs.

During this study, 12 mice with kidney tumors were subjected to hypoxia, and as a result, they exhibited increases in cells that play a role in building blood vessels.

"Although this is an experimental study, it is remarkable, because it demonstrates the influence of oxygen deficiency on the growth of renal cell carcinoma tissue (both primary tumor as well as metastases)," Professor Arnulf Stenzl, Chair of the EAU Congress Committee, said in a statement.

According to Stenzl, this study might explain why healthy habits that increase oxygen in the blood result in better outcomes for cancer patients.

"It may be postulated that increased oxygenation of the blood may be the underlying mechanism why not smoking or giving up smoking, regular sport activity (especially endurance type sports), reducing the body mass index and other lifestyle changes that increase tissue oxygenation have a supportive beneficial effect on better outcomes in renal cell cancer as well as other tumor types," Stenzl said in the statement.

This study was presented March 12 at the European Association of Urology Congress in Munich, Germany.

Funding sources and disclosures were unavailable at time of publication.