PPARD and malignant colon neoplasm: In summary, we show a model that the oncoprotein HBXIP promotes the proliferation of colonic cancer cells via activating PPARδ, in which HBXIP, functioned as a co-activator of NF-κB, up-regulated the expression of PPARδ, and the PPARδ conversely up-regulated the expression of NF-κB through activating its transcription activity (Supplementary Figure 5).