CXCL12 and hepatocellular carcinoma: In addition, sorafenib treatment was found to increase hypoxia and SDF1α/CXCR4 expression in HCC cells and animal tumor models, whereas inhibition of the SDF1α/CXCR4 pathway overcame the sorafenib resistance in HCC (Chen et al., 2014; Chen et al., 2015).