Expression of Th1- Th2- and Th17-associated cytokines in laryngeal carcinoma.

T-helper (Th) 0 cell differentiation into Th1 or Th2 cells is dependent on a number of transcription factors that act at specific time points to regulate gene expression. Th17 cells, a subset of interleukin (IL)-17-producing T cells distinct from Th1 or Th2 cells, are considered to exhibit a critical function in inflammation and autoimmune diseases, as well as cancer development. In the present study, the expression of Th1-, Th2- and Th17-associated cytokines in laryngeal cancer and pericarcinoma tissues obtained from 57 laryngeal carcinoma patients was investigated. The association between Th1, Th2 and Th17 infiltration and tumor development was also evaluated. Reverse transcription-polymerase chain reaction and western blotting results revealed that the mRNA and protein expression of Th2 cytokines was lower, while the expression of Th1 and Th17 cytokines was higher in tumor tissues than in pericarcinoma tissues. Furthermore, the early stage cancer patients exhibited a higher level of interferon-γ, IL-2 and IL-17 mRNA expression than those at advanced stages. Cancer tissues exhibited higher Th17 cytokine expression than pericarcinoma tissues. By contrast, Th1 cytokine expression was increased in pericarcinoma tissues compared with cancer tissues. These results indicate that high expression of Th1- and Th17-associated cytokines in laryngeal carcinoma may contribute to suppression of cancer development and a relatively good prognosis.