Characterization and Tumorigenicity of Spheroids Composed of Pigmented or Non Pigmented B16 Melanoma Cells; Gillet, Marie-Claire ; et alin In Vivo (Athens, Greece) (1994), 8(3, May-Jun), 333-8 A parental line of mouse B16 melanoma cells (B16) and two derived cloned lines, either pigmented (B16P) or non pigmented (B16NP), were cultured in vitro as spheroids. After 48 hrs, the pigmented cells ... [more ▼] A parental line of mouse B16 melanoma cells (B16) and two derived cloned lines, either pigmented (B16P) or non pigmented (B16NP), were cultured in vitro as spheroids. After 48 hrs, the pigmented cells (B16, B16P) formed smaller and looser aggregates, with higher rates of cell proliferation and lower amounts of extracellular matrix as compared to B16NP spheroids. The three lines were more tumorigenic when inoculated subcutaneously as spheroids than as isolated cells. Furthermore, B16P or B16 spheroids developed richly vascularized subcutaneous tumors and metastases more rapidly than B16NP aggregates. After intravenous injection of spheroids, the measurement with an image analyzer of the area of sections in lung colonies indicated that B16P colonies were larger and more numerous than those induced by B16NP cells. [less ▲] Detailed reference viewed: 18 (2 ULg) Reevaluation by Image Analysis of the Effects of Fibroblasts, Fibronectin or Laminin Upon Colony Formation in Mouse Lungs by B16 Melanoma Cells; ; et al in Invasion & Metastasis (1993), 13(4), 201-11 A recently described personal method based on image analysis of histological sections was used in order to quantify lung colony formation by B16 melanoma cells injected intravenously into the mouse. These ... [more ▼] A recently described personal method based on image analysis of histological sections was used in order to quantify lung colony formation by B16 melanoma cells injected intravenously into the mouse. These tumor cells were preincubated in vitro either with fibronectin (FN), laminin (LN) or fibroblasts (FB), which are implicated in the process of invasion and metastasis. Thanks to this method, a more accurate analysis of lung colonies (section area and number) formed by tumor cells was realized. By image analysis, we show that when FB were mixed with B16 cells, a drastic increase of tumor sections number and area was induced. LN increased the tumor sections area, but not their number. No effect of FN on B16 cells was observed. LN and FN promoted tumor anchorage in the depth of the lungs while FB reduced the latter. These facts could explain the contradictory results obtained by simply counting macroscopically superficial lung colonies. When cultured in vitro, these B16 melanoma cells did not produce any type of IV collagenase, either alone or in the presence of LN or FN, but in cocultures (B16 with 3T3) and in fibroblasts cultures, this enzyme was present. This could explain, among other factors, why the rate of invasiveness exerted by B16 cells is higher when the latter are coinjected with FB. [less ▲] Detailed reference viewed: 11 (3 ULg) Laminin and 67 Kd Laminin Binding Protein in Mouse B16 Melanoma Cells and 3t3 Fibroblast Spheroids; Munaut, Carine ; et alin Anticancer Research (1992), 12(6B, Nov-Dec), 2011-6 Multicellular spheroids which promote cell-cell and cell-matrix interactions were prepared in culture with mouse B16 melanoma cells (pigmented or non pigmented) alone or mixed with mouse 3T3 fibroblasts ... [more ▼] Multicellular spheroids which promote cell-cell and cell-matrix interactions were prepared in culture with mouse B16 melanoma cells (pigmented or non pigmented) alone or mixed with mouse 3T3 fibroblasts. Their volume and proliferation or necrosis rate were evaluated. As measured by dot blot immunoassay, laminin was mainly produced by fibroblasts rather than by melanoma cells. High levels of laminin B1 chain mRNA were detected only in spheroids composed of 3T3 fibroblasts. The levels of 67 kD laminin binding protein mRNA were high in all cell populations studied here. [less ▲] Detailed reference viewed: 29 (3 ULg) |
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