CXCL5 and gastric cancer: 5-FU-sensitive gastric cancer cells were cultured alone or co-cultured with MR macrophages with the presence of rhCXCL5 (10 ng/ml) or CXCL5 neutralizing antibody (0.5 μg/ml) for 48 h followed by being treated with different concentrations of 5-FU (0, 5, 10, 20, 40, 80, 120, 160, 200 μg/ml) for 24 h, then the cell survival rates were assessed.