CXCL8 and metastasis: In addition, high IL-8 expression was significantly associated with lymphatic metastasis (OR = 2.24, 95%CI 1.39–3.63, I2 = 0%, fixed effect) (Fig 3B), and liver metastasis (OR = 3.47, 95%CI 1.74–6.89, I2 = 0%, fixed effect) (Fig 3C), indicating that IL-8 might be a potential indicator for metastasis of colorectal cancer.