CXCL8 and cholangiocarcinoma: In the special case of PDAC, high levels of IL-8 are also related to aggressive tumor behavior and poor prognosis, with evidence that includes PDAC cell line models (46), high blood levels in PDAC and cholangiocarcinoma patients (47, 48), and over-expression of IL-8 and its receptors in tumor tissue (49) and inflammatory cells infiltrating the tumor (50).