Of these genes, CXCL12, a chemokine and its cell surface receptor, CXCR4, and CXCR2 which are known to be involved in cancer cell proliferation and metastasis were verified by qRT-PCR to be significantly increased by ~3-fold in the HCC97L cells transfected with the CPE-ΔN expression plasmids. Here, CXCL12 is linked to cancer.