Tumor metastases and cell‐mediated immunity in a model system in DBA/2 mice. I. Tumor invasiveness in vitro and metastasis formation in vivo

Abstract

A syngeneic model system for the study of tumor metastases and cell-mediated immunity is described. The system consists of two related, chemically induced murine lymphomas, the non-metastasizing parental line Eb and i t s metastasizing variant ESb. A n unrelated, chemically induced tumor (MDAY) i s included for specificity controls. Serological typing revealed that both Eb and ESb were of T lymphoid origin and expressed the H-2K and H-2D molecules of the host strain DBA/2. By various electron microscope techniques, morphological differences were observed between the t w o cell lines. I n comparison t o Eb cells, ESb tumor cells had a more polymorphic nucleus with many invaginations of the nuclear envelope and a more prominent expression of microvilli on the cell surface. A n in vitro organ culture test for tumor invasiveness, presented here for the f i r s t t i m e In a syngeneic murine system, revealed that ESb but not Eb tumor cells had the ability t o attach t o and invade normal tissue. Accordingly, ESb tumor cells showed higher malignancy in vivo. This was apparent from their higher tumorigenicity and their ability t o disseminate and metastasize and t o kill recipient mice more quickly. Upon histological examination of the local primary tumors a striking difference was noticed with regard t o the degree of infiltration by host-derived mononuclear cells, mostly histiocytes. The non-metastasizing tumor Eb was heavily infiltrated while tumor ESb contained only a few of these cells. The differences between the tumor lines ESb and Eb are considered i n the light of their possible relevance for metastases in general. The etiology of the t w o tumors i s discussed in particular with respect t o their relatedness.Metastasis, the spread of malignant cells from a primary site to distant organs, represents one of the most intriguing problems in the pathogenesis and treatment of cancer (see Willis, 1973;Fidler and Kripkie, 1977; Carter, 1978). While primary tumors in many instances can be removed surgically it is the subsequent development of metastases which often cannot be prevented and is responsible for most therapeutic failures (Krokowski, 1978). In spite of its importance, relatively little is known about the processes which either lead to or prevent formation of tumor metastases. One reason for this is that experimental tumors in animals are often not suitable for the study of metastasis: they either do not metastasize or they grow so fast that they kill the host before metastases can develop (Kim, 1970;Mellgren, 1976 The majority of experimental tumors induced by either tumor viruses or chemical carcinogens and maintained by long-term transplantations usually express immunogenic tumor-associated transplantation antigens (TATA) against which syngeneic animals can be successfully immunized. When similar immunization procedures were applied to humans, a significant protective effect was observed only occasionally (see Terry and Windhorst, 1978). The meager success in cancer patients of specific immunotherapy prot...

Interactions among clonal subpopulations affect stability of the metastatic phenotype in polyclonal populations of B16 melanoma cells.

“…1). Isolation and comparison of tumor cell clones (2)(3)(4)(5)(6) or sublines (7)(8)(9)(10)(11)(12)(13)(14)(15) that have different metastatic abilities offers new opportunities for correlating specific cellular alterations with the metastatic phenotype. The success of this approach will depend, however, on the stability of the metastatic phenotype in these subpopulations during serial passage in vivo or in vitro.…”

Murine interferon-α1 gene-transduced ESb tumor cells are rejected by host-mediated mechanisms despite resistance of the parental tumor to interferon-α/β therapy

“…10 ESb lymphoma cells were obtained from V. Schirrmacher (Deutsches Krebsforschungszentrum Heidelberg, Germany) and were passaged by intraperitoneal injection into DBA/2 mice. ESb cells were cultivated in RPMI 1640 supplemented with 10% fetal calf serum (FCS), 100 M 2-mercaptoethanol, 20 M N-2-hydroxyethylpiperazine-NЈ-2-ethanesulfonic acid, 1% nonessential amino acids, and 1 mM sodium pyruvate.…”

“…Metastatic development was inhibited, and mouse survival time was increased markedly. [7][8][9] In this study, we have transduced the highly metastatic lymphoma ESb 10 with the mouse IFN-␣ 1 gene. This tumor is also totally resistant to mouse IFN-␣/␤ in vitro.…”

Matrix heparan sulphate, but not endothelial cell surface heparan sulphate, is degraded by highly metastatic mouse lymphoma cells

“…We have now studied the substrate specificity of the endoglycosidase described for the Eb/ESb tumour system on purified proteoglycans. The experimental system described here consisted of the murine methylcholanthrene-induced, low metastatic T lymphoma Eb, its highly metastatic variant ESb (Schirrmacher et al, 1979) and a low-metastatic variant of ESb, ESb-MP, which was selected for its plastic-adherent growth in vitro (Fogel et al, 1983). Eb and ESb cells were distinguished from each other by their specific expression of differentiation antigens (Altevogt et al, 1982), tumourassociated transplantation antigens (TATA) and cell surface glycoconjugates (Schwartz et al, 1984; whereas the variant ESb-MP is more closely related to the cell line ESb -both cell types express identical differentiation antigens and TATA (Fogel et al, 1983).…”