STAT3 and head and neck cancer: Head and neck cancer cells have been shown to express a variety of pro-inflammatory and pro-angiogenic cytokines (Chen et al, 1999; Ondrey et al, 1999) and to respond to IL-6 stimulation with upregulation of Stat3 phosphorylation and promotion of cell growth; reversal of this process could participate in the observed effects of 15-PGJ2 on oral SCCa cells.