SPONTANEOUS PRODUCTION OF INTERLEUKIN-8 BY HUMAN LUNG-CANCER CELLS AND ITS AUGMENTATION BY TUMOR-NECROSIS-FACTOR-ALPHA AND INTERLEUKIN-1 ATPROTEIN AND MESSENGER-RNA LEVELS

A cell-to-cell interaction between tumors and host inflammatory eels i s important for the subsequent cancer progression or regression. We ex amined the expression of interleukin-8 (IL-8) mRNAs by 9 human lung ca ncer cell lines and the influences of cytokines on IL-8 production and its gene expression. Substantial expressions of IL-8 gene were detect ed in 3 lung cancer cell lines (RERF-LC-OK, Lu-134-A-H, YO-88 cells). Moreover, 4 lung cancer cell lines (RERF-LC-MS, RERF-LC-OK, A549 and Y O-88) were used to examine the effects of exogenous cytokines - interl eukin-1 beta (IL-1 beta), tumor necrosis factor alpha (TNF-alpha) and granulocyte-macrophage colony-stimulating factor - on IL-8 production by the cells at protein and gene levels. TNF-alpha and IL-1 beta signi ficantly augmented the levels of mRNA expression for IL-8 and its prod uction. These observations indicate that tumor-derived IL-8 may be imp ortant in recruiting inflammatory neutrophils and promoting interactio n between lung cancer and inflammatory cells.