CXCL8 and neoplasm: The two tumor-derived samples having high IL-6 levels also showed increased IL-8 secretion (BE133 marked in yellow, and BE144 marked in blue), but this effect was not observed in all matched samples (p = 0.136 for control, p = 0.070 for Jagged-1, p = 0.063 for TGF- β1, n = 6).