Abstract
Large amount of IL-8 was found to be produced by five human liver tumor cell lines, and the production was augmented by the addition of IL-1β or TNF-α, but not by IFN-γ. Northern blot analysis demonstrated that IL-8mRNA expression was increased in the presence of IL-1β or TNF-α. Reverse transcription polymerase chain reaction showed that all hepatocellular carcinoma (HCC) tissues examined in this study expressed IL-8mRNA. In vitro analyses using human umbilical vein endothelial cells (HUVECs) demonstrated that conditioned medium of PLC/PRF/5 cells as well as recombinant IL-8 stimulated the proliferation of HUVECs in a dose-dependent manner, and the stimulatory effect was partially inhibited by the addition of neutralizing antibody against IL-8. Our present data indicate that IL-8 produced by HCC cell lines has an angiogenic activity.
