Altered experimental metastasis pattern by proteolytic cell treatment.

We have studied some cellular characteristics and the transplantability of a newly induced squamous cell carcinoma, Sq1-SC, in comparison with the ascites-transformed subline of the same tumor, Sq1-AA. We could demonstrate that the AA tumor differed from the SC tumor in the pattern of intravenously induced 'experimental metastases'. The SC tumor preferentially gave rise to extrapulmonary tumor colonies ('metastases'), while the AA tumor exclusively gave rise to lung colonies. Comparison with the ascites tumor growing in solid form subcutaneously (AS tumor) shows that the enzymatic treatment, which is necessary to bring solid tumors into viable and dissociated suspensions, can have a decisive influence on tumor cell lodgement in vessels and metastasis.