Clonal tumorigenic endodermal cell lines producing basement membrane components.

Tumors were developed from the mouse teratocarcinoma-derived endodermal cell line PF HR-9 by subcutaneous injections in syngeneic mice of large numbers of cells previously cultured for several years at high cell density. Cell cultures were established from the tumors and the cells were cloned. The cloned sublines were highly malignant in vivo and tumor metastases were occasionally observed. The tumors contained abundant extracellular material, which was distinctly laminated and contained type IV collagen, laminin, and heparan sulfate proteoglycan. The tumorigenic sublines were also shown to have retained markers of the original cells, such as the cytoskeletal proteins Endo A and B. These cell lines should be useful for biosynthetic studies on basement membrane and cytoskeletal components and the tumors for isolation of these macromolecules and their mRNAs.