Serum interleukin-6 and-10 levels in patients with gastric cancer

Interleukin-6 (IL-6) is known to be a multifunctional cytokine and IL-10 is an immunosuppressive factor. Both have been reported to be related to the disease prognosis in some human solid tumors. In the present study, we evaluated the clinical significance of preoperative serum IL-6 and IL-10 levels as new tumor markers in patients with gastric cancer (GC). Preoperative serum samples from 90 patients with GC and 9 normal healthy volunteers were assayed. Levels of IL-6 and IL-10 were determined by enzyme-linked immunosorbent assay (ELISA). The clinical significance of serum IL-6 and IL-10 levels was evaluated and compared with serum carcinoembryonic antigen (CEA) levels and serum C-reactive protein (CRP) levels in these patients. The serum level of IL-6 was significantly higher in the GC patients than in the healthy subjects. Serum IL-6 levels were strongly correlated with CRP levels, but did not correlate with CEA or carbohydrate antigen (CA) 19-9 levels. Serum IL-10 levels did not correlate with CEA, CA19-9, or CRP. Strong positive correlations between serum IL-6 levels and tumor size and tumor stage were observed. On the other hand, IL-10 did not correlate with such clinicopathological findings of tumors. However, high serum IL-10 levels were associated with a worse prognosis in the GC patients, independently of their tumor stage. These findings indicate that serum IL-6 may suggest gastric cancer progression. On the other hand, IL-10 may play an important role in host immunity and the prognosis of GC patients.