CXCL12 and cancer: Our previous study showed that activation of CXCR4 maintained the self-renewal capacity of OV6+ HCC cells.20 The CXCL12/CXCR4 pathway has been implicated in various types of cancers.34 Both the autocrine and paracrine effects of this pathway have been shown to maintain cancer growth and progression.35 Therefore, we investigated whether HBx/MDM2 regulated the stemness of OV6+ CSCs through the CXCL12/CXCR4 pathway.