CXCL6 and neoplasm: RT-PCR results demonstrated CXCL1 and CXCL8 were significantly high-expressed in tumor tissues, however, there was no significant difference in the expression of CXCL2, CXCL3, CXCL6 and CXCL7 between normal and tumor tissues (Supplementary Figure 1) in RT-CPR results.