Detection of Early Malignant Changes in Tissue Cultured Cells Using a Novel Tumorigenicity Assay in Nude Mice

摘要

Cultured cells were tested for tumorigenicity in nude mice using a new test involving implantation of cells grown on small gelatin sponges. The test was applied to mouse, hamster, and human cells, and the results were compared to a conventional tumorigenicity assay (injection of cell suspensions). The sponge assay was at least as sensitive as the conventional assay in all cases tested so far. In several instances the sponge assay could detect events not seen in the standard assay. Use of the sponge assay has led to interesting possibilities for studying in vitro and early in vivo cellular changes that may be associated with the ability to form tumors. In studies with two human squamous cell carcinoma cell lines, the two assays yielded comparable results. Such cell lines might provide a system in which the lack of terminal differentiation within a cell population could be examined as a parameter of neoplastic change. (ERA citation 04:057131)