Overall, we have demonstrated that nuclear localization of β-catenin (a tissue biomarker of β-catenin-related transcription) is increased in transgenic Cox-2-over-expressing cLys-Cox-2 x ApcMin/+ mouse tumours and that paracrine macrophage Cox-2 activity directs increased β-catenin levels and transcriptional activity in epithelial cells. The gene discussed is PTGS2; the disease is neoplasm.