Organ preferential metastasis related to tissue- and serum-selective growth or migration properties of hamster pancreatic carcinoma cells

We have investigated tissue- and serum-selective growth or migration activities of two hamster pancreatic carcinoma cell lines, KH-PC and HapT1. In experimental metastatic models, multiple liver metastases were observed for hamsters injected with KH-PC cells, while HapT1 had little tendency to metastasize to the liver. Micrometastases in the lung were observed for both KH-PC and HapT1. Liver extract inhibited the growth of HapT1 cells when compared to a 1% bovine serum albumin control, while KH-PC growth was not inhibited by liver extract. Liver extract showed chemoattractive activity to KH-PC but not to HapT1 cells. No notable differences were shown in either chemoattractive or growth properties of lung extract toward either cell line. These activities of lung extracts were weaker than those of liver extract to KH-PC. Hamster portal vein serum (PVS) had higher mitogenic activity toward both KH-PC and HapT1 cells, compared with serum derived from the vena cava (VS). Chemokinetic activity of PVS or VS toward KH-PC was slightly higher than that toward HapT1. In a chemoinvasion assay with liver extract and PVS, a 6-fold greater number of invasive cells was observed for KH-PC cells when compared to HapT1 cells. In a chemoinvasion assay with lung extract and VS, there was no difference between the cell lines. Our results suggest that complex activities of tissue- and serum-selective growth or migration were related to organ preferential metastasis of these hamster pancreatic carcinoma cell lines.