Mechanism of the Proteolytic Activity of Malignant Tissue Cells


THE proteolytic activity displayed by malignant tumour cells in vitro has often been the main hindrance to cultivating permanent strains of these cells. The liquefaction of the culture medium by the malignant cells, which has attracted much attention, suggested to me years ago1 that the proteolytic activity of the tumour cells was fully, or in part, responsible for their malignant properties. By the liquefaction the healthy tissue cells in the neighbourhood are deprived of their solid supports, and consequently the way is prepared for further infiltration deep into the normal tissues.

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  1. 1

    Fischer, A., Arch. Entwicklungsmech., 104, 210 (1925).

  2. 2

    Fischer, A., and Laser, H., Z. Krebsforsch., 26, 80 (1927).

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FISCHER, A. Mechanism of the Proteolytic Activity of Malignant Tissue Cells. Nature 157, 442 (1946) doi:10.1038/157442c0

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