Characterization of two murine tumor sublines selected purely in vivo for specific metastatic patterns

We have attempted to clone an ascites tumor, MCB 21-AA, which was originally a fibrosarcoma, by transplantation of spontaneous metastases from the lungs or a lymph node to a subcutaneous site, and by repetition of this procedure ten times. We isolated two tumor sublines, LU (from lung) and LN (from lymph node), which differ from the original tumor in several cell characteristics. When tested for the formation of experimental metastasis, these sublines disseminate in the same manner as the original tumor. We interpret this finding as an argument against the widely held view that metastasis is a highly selective cloning process.