The estimation of endogenous tumor necrosis factor alpha and cortisol levels in serum in advanced neoplasm

The immune reaction mediators--cytokines may play an important role in central nervous system function and influence the neuroendocrine system. The aim of the study was to assess the hypothesis of a possible correlation between endogenous TNF-alpha and glucocorticoids secretion in advanced neoplasm. Thirty patients (17 males and 13 females) with advanced neoplasm were enrolled in the study. The levels of TNF-alpha were measured with ELISA type test and cortisol levels were estimated by RIA method. The blood samples were collected 6 times during 24-hours for TNF and 6 times a day for cortisol. Twenty healthy volunteers were studied in parallel. Both TNF-alpha and cortisol levels revealed the presence of circadian rhythm in examined patients. The levels of TNF-alpha were very high and achieved the peak value about midnight (acrophase-01.40). Cortisol peak was found typically at 08.08. The fluctuations of examined molecules showed regular patterns. TNF-alpha levels markedly decreased together with the increase of cortisol and rose when cortisol concentration in serum was low. Although the correlation was not confirmed by Spearman correlation rank the shapes displayed by both curves may suggest the presence of neuroendocrine feed-back loop between corticosteroids and TNF-alpha in advanced cancer.