RGN and embryonal carcinoma: Stable and high level expression of SMP30/regucalcin has been demonstrated in several eukaryotic cell lines that include human hepatocellular carcinoma Hep G2, Rat hepatoma H4-II E, mouse embryonic carcinoma PC19 and normal rat kidney proximal tubular epithelial NRK 52E [10], [22]–[26].