However, only in pancreatic cancer patients, S1P plasma concentrations were significantly correlated with the absolute numbers of circulating PB VSELs, MSCs and HSCs (r = 0.59, −0.63 and 0.71, respectively, P < 0.01 for all), as well as, with systemic SDF-1 level (r = 0.85, P = 0.004). The gene discussed is CXCL12; the disease is pancreatic neoplasm.