Three cytokines were significantly higher in the serum of subjects with endometriosis than in the control group: interleukin-6 (IL-6) [4.41 pg/ml (range: 1.47-15.01) versus 0.97 pg/ml (range: 0.29-2.98), respectively; p<0.001], monocyte chemotactic protein-1 (MCP-1) [37.91 pg/ml (range: 24.54-94.74) versus 22.13 pg/ml (range: 13.85-39.45), respectively; p<0.001], and interferon-gamma (INF-gamma) [19.01 pg/ml (range: 1.19-73.52) versus 0.30 pg/ml (range: 0.00-13.05), respectively; p<0.001].
In contrast, the percentages of CD14+ cells producing TNF-alpha, IL-6, IL-10, MCP-1, and IL-8 were significantly higher in PB than PF of women with endometriosis.
Our results suggest that the IL-6 -634C/G and ICAM-1 469K/E polymorphisms synergistically affect the susceptibility for endometriosis in the Japanese population.
IL-6 and TNFalpha are involved in the production of HGF by endometrial stromal cells and may be involved in the growth of endometriosis by an autocrine mechanism.