[Characteristics of high- and low-metastatic clones isolated from murine undifferentiated sarcoma (RCT sarcoma)]

We have established low- and high-metastatic clones from the undifferentiated RCT (Radiological Science-Chiba Cancer Center-Toyama Medical and Pharmaceutical University) sarcoma spontaneously developed in a C3H/He male mouse. Metastatic lesions of RCT sarcoma at the lung were inoculated into the subcutaneous tissue which was then cultured and cloned. Clones potential of low- and high-metastatic were named RCT(-) and RCT(+), respectively. RCT(-) cells were cloned by the limiting dilution method in vitro and RCT(+) cells were cloned by the combination of lung passages and limiting dilution methods. After 20 serial passages in vitro, the metastatic potential of each clone remained unchanged. Significant differences were noted in their growing property and adhesiveness to plastic or collagen-coated surfaces; RCT(+) cells grew more slowly, adhered more rapidly and firmly to the surfaces than those of RCT(-) cells. RCT(+) cells were agglutinated by all types of lectins used in this study, while several types of lectins could not agglutinate RCT(-) cells. These results would indicate that there was the difference in oligosaccharide residues on the surface of each cell. No significant difference between these cell clones in their sensitivity to natural killer cell-mediated cytotoxicity in vitro. We believe that RCT(-) and RCT(+) cells are very useful experimental model to study the mechanism of sarcoma metastasis.