Chronic Stress Hastens Induced Skin Cancer in Mice
Study finds that stress suppresses type 1 cytokines and protective T cells
FRIDAY, Dec. 9 (HealthDay News) -- Chronic stress accelerates the emergence and development of squamous cell carcinomas in mice, according to a study published in the Dec. 7 issue of the Journal of the National Cancer Institute.
Firdaus Dhabhar, Ph.D., of Ohio State University in Columbus, and colleagues exposed 16 mice susceptible to UV-induced tumors to UVB radiation three times a week for 10 weeks, and left four susceptible mice unexposed. While half of the exposed mice remained in their cages for the duration of the experiment, half were chronically stressed by being restrained from week four to week six.
The researchers found that the stressed mice developed tumors at a median of 15 weeks compared to 16.5 weeks in the unstressed mice. Stressed mice also reached 50% incidence earlier than controls (15 weeks versus 21 weeks).
"Chronic stress increased susceptibility to UV- induced squamous cell carcinoma in this mouse model by suppressing type 1 cytokines and protective T cells and increasing regulatory/suppressor T cell numbers," the researchers conclude. "These findings may be relevant for conditions in which chronic stress may increase susceptibility to other cancers, decrease effectiveness of tumor immunotherapy or contribute to systemic immunosuppression during cancer treatment."