ObjectiveTo explore the changes of cytokines in the tumor microenvironment of colorectal cancer and the relationship between the expression of CD16a mRNA and cytokines in the microenvironment.MethodsRT-PCR and flow cytometry microsphere array (CBA) were used to detect the expressions of CD16a mRNA, as well as cytokines of Th1 ［interleukin (IL)-2, IL-12, and interferone-γ (IFN-γ)］, Th2 (IL-4, IL-6, and IL-10), tumor necrosis factor-α (TNF-α), and vascular endothelial growth factor (VEGF) in the tumor and the adjacent tissues of 42 patients with colorectal cancer, respectively, and the correlation between the expression of CD16a mRNA and cytokines in the microenvironment was analyzed.ResultsThe expressions of IL-6, TNF-α, and VEGF in colorectal cancer tissues were significantly higher than those in the adjacent tissues (P<0.05). There was no significant difference in the expression of IL-2,IL-4, IL-10, IL-12, and IFN-γ between the two kinds of tissues (P>0.05). Clinicopathological factor analysis showed that, the levels of IL-6 and VEGF in the colorectal cancer patients with preoperative normal CEA were significantly higher than those with elevated CEA (P<0.05). Correlation analysis showed that the expression of IL-6 was negatively correlated with expression of CD16a mRNA (P<0.05).ConclusionsThe expressions of IL-6, TNF-α, and VEGF in tumor tissues were significantly higher than adjacent tissues, and the effect of angiogenic and immunosuppression were enhanced. The expression of CD16a mRNA in the microenvironment of colorectal cancer tumor is negatively correlated with the expression of IL-6.