FOOTPRINTING OF INDIVIDUAL TUMORS AND THEIR VARIANTS BY CONSTITUTIVE CYTOKINE EXPRESSION PATTERNS

We have examined the cytokine mRNA expression profile of six different human cell lines derived from Ewing sarcomas using polymerase chain r eaction and found each to constitutively express a characteristic patt ern. Furthermore, each cell line differed in the levels of secreted cy tokines. We also analyzed the expression of several cytokines in murin e UV-induced sarcomas and their heritably stable progressive variants. Each murine tumor also constitutively expressed a large number of cyt okines, and in some cases, the more malignant variants differed from t heir parental tumors. These results demonstrate that tumors of the sam e type, and even in the same lineage, can have distinct cytokine expre ssion and/or secretion profiles. Some cytokines may stimulate tumor gr owth while others may have antitumor effects. Cytokine therapy may be tailored depending upon the cytokine profile of the individual maligna ncy.