Assessment of the metastatic ability of rat hepatoma cells in chick embryos by the polymerase-chain reaction.

To elucidate the degree of malignancy or the host-killing ability of rat ascites hepatoma AH66F, AH66 and AH130, the chick embryo-polymerase chain reaction system was used to measure the metastasis of these hepatoma cells. When inoculated into the chorioallantoic membrane vein of 10-day fertilized chicken eggs, AH66F cells metastasized in the lung and liver in an inoculum size-dependent manner up to 10(6) cells, but AH66 and AH130 cells only a little even at 10(6) cells. The adhesion of AH66F cells, but not other hepatoma cells, to rat mesentery-derived mesothelial cells was inhibited by protein kinase C inhibitors NA-382 and H-7, but not by other protein kinase inhibitors, and the life-span of rats inoculated with AH66F cells was also prolonged by treatment with Na-382. AH66F cells, pretreated with protein kinase inhibitors were inoculated into the fertile eggs and micrometastasis was assayed. Metastasis of AH66F cells in the chick embryo was clearly decreased by treatment with NA-382. The chick embryo-polymerase chain reaction system is a sensitive method to measure the metastatic ability of mammalian tumor cells, and the high metastatic ability of AH66F cells is probably related to their adhesion to target cells mediated by the protein kinase C pathway.