Endogenous glucocorticoids suppress growth and spread of cancer

the Oncology Nurse Advisor take:

According to new findings published in the journal Nature Communications, researchers at the Weizmann Institute of Science in Rehovot, Israel, have found that cancer may grow and spread more during nighttime compared to daytime.

For the study, the researchers wanted to investigate the relationship between the epidermal growth factor receptor (EGFR), a receptor involved with the growth and spread of cancer cells, and the receptor to which glucocorticoids bind. Glucocorticoids are steroid hormones, such as cortisol and cortisone, that play a role in maintaining the body's energy levels during the day and dealing with a stressful situation.

In the study, the researchers found that cell migration is inhibited when the glucocorticoid receptor is bound to its corresponding steroid hormone. Since cell migration is promoted by the EGFR, the researchers wanted to determine whether the relationship between the two receptors is different during nighttime versus daytime. They found that the EGFR was more active during sleep versus waking hours in mice.

Then, the researchers gave lapatinib, a new EGFR inhibitor, to mice at different times of the day. Mice receiving the drug during sleep had significantly decreased tumor burden, suggesting that glucocorticoid levels enhance or inhibit the growth and spread of cancer.