CXCL6 and cholangiocarcinoma: Notably, overexpression of CXCL6 was reported in high‐stemness malignant CCA cells;[22] it was also found to promote tumor progression in hepatocellular carcinoma (HCC) and non‐small cell lung cancer,[23, 24] and to regulate neutrophil infiltration in gastric cancer.[25] However, the function and mechanism of CXCL6 in CCA have not been investigated in detail.