IL-6 is an inflammatory cytokine that in healthy young people is almost undetectable. Levels of IL-6 increase with age, chronic psychological stress, and disease. Previous studies in humans and laboratory animals have shown IL-6 levels are also influenced by behavioral factors.
IL-6 has previously been shown to promote tumor growth, and IL-6 levels are also prognostic in ovarian cancer, with elevated levels associated with higher mortality and metastatic disease. Because depression and chronic stress are commonly associated with ovarian cancer, and IL-6 levels are responsive to psychosocial factors, Erin S. Costanzo, M.A. from the University of Iowa and colleagues investigated whether IL-6 levels were linked to psychosocial factors in 61 women with advanced ovarian cancer.
While levels of IL-6 and the incidence of depression were elevated in these patients, those who reported strong social attachments had significantly lower levels of IL-6 in both the blood and in the ascites fluid surrounding the tumor. Women with weak social attachments had 1.7 times more IL-6 in the circulating bloodstream and 2.5 times more in the ascites fluid surrounding the tumor than women with strong social attachments. Higher levels in the bloodstream were also found among women who reported poor quality of life, such as fatigue and decreased physical function.
The investigators conclude, that "the finding that social attachment is strongly related to IL-6 not only in the periphery but also in the vicinity of the tumor suggests that psychosocial factors may indeed be important clinically" in the course of ovarian cancer.
Article: "Psychosocial Factors and Interleukin-6 among Women with Advanced Ovarian Cancer," Erin S. Costanzo, Susan K. Lutgendorf, Anil K. Sood, Barrie Anderson, Joel Sorosky, David M. Lubaroff, CANCER; Published Online: June 13, 2005 (DOI: 10.1002/cncr.21147); Print Issue Date: July 15, 2005.
Journal
Cancer