CXCL12 and hepatocellular carcinoma: We cannot deny the relationship between rupture of a hepatocellular carcinoma and sitagliptin administration, because recently it has been demonstrated that CXCR4/CXCL12 axis exerts a variety of functions at different steps of hepatocellular carcinoma progression, and CXCL12 may be inactivated by DPP-4 cleavage (Ismael et al. 2014).