Cytokine-induced pseudopodial protrusion is coupled to tumour cell migration

Fourier analysis of cell motility: correlation of motility with metastatic potential

We report the development of a computerized, mathematical system for quantitating the various types of cell motility. This Fourier analysis method simultaneously quantifies for individual cells (i) temporal changes in cell shape represented by cell ruffling, undulation, and pseudopodal extension, (ii) cell translation, and (iii) average cell size and shape. This spatial-temporal Fourier analysis was tested on a series of well-characterized animal tumor cell lines of rat prostatic cancer to study in a quantitative manner the correlation of cell motility with increasing in vivo metastatic potential. Fourier motility coefficients measuring pseudopodal extension correlated best with metastatic potential in the cell lines studied. This study demonstrated that Fourier analysis provides quantitative measurement of cell motility that may be applied to the study of biological processes. This analysis should aid in the study of the motility of individual cells in various areas of cellular and tumor biology.

Pinocchio cells: morphologically atypical immunologically heterogeneous lymphocytes induced by treatment with interleukin 2

We describe a novel cell type, the Pinocchio cell, that appears in the peripheral blood of all patients receiving treatment with interleukin 2, up to 20,000 cells/microliter. This cell is characterized by a prominent and granular proboscis with which it attaches to tumor cells and mediates tumor cell lysis. Pinocchio cells are immunologically heterogeneous and express antigens of both T and NK cells; Pinocchio cells are adherent in culture and are more cytolytic than non-adherent cells against NK-sensitive and resistant tumor cells. Incubation of normal whole human blood for 1 h induces Pinocchio morphology of mononuclear white blood cells.

Growth regulation of cancer metastases by their host organ

We analyzed mechanisms responsible for organ-specific metastasis by using two melanoma sublines derived from the same mouse tumor, of which one colonizes the lungs (F10) and the other colonizes the liver (L8) after intravenous injection. Both lines were obtained by selective growth in lung or liver after injection of tumor cells into a tail vein or portal vein. Contrary to common concepts, the cells of the liver-colonizing melanoma line do not accumulate preferentially in the liver after intravenous administration in vivo. However, the selective survival and proliferation of these melanoma cells in the target organ (liver) may be explained by the unexpected observation that they can be specifically stimulated to proliferate in the presence of hepatocytes, whereas the cells of the lung-colonizing line cannot. Growth promotion under coculture conditions in vitro was monitored both by thymidine incorporation into DNA and by increase in cell numbers. The proliferative stimulus is not mediated by an easily diffusible factor but rather depends upon direct contact between liver cells and those tumor cells that metastasize to that particular organ.

Gene products which play a role in cancer invasion and metastasis

Invasion requires a number of distinct tumor cell interactions with host tissue, beginning with attachment to the matrix, followed by hydrolysis of matrix material and locomotion. Gene products which may be involved in these steps are discussed here. Laminin receptors and integrins have roles in the adhesion phase, while certain collagenases are prominent among the matrix-degrading enzymes. Autocrine motility factors, distinct from growth factors, appear to be involved in tumor cell locomotion. Finally, certain oncogenes, particularly of the ras family, are closely related with metastatic potential. A detailed understanding of the molecular biology of invasion and metastasis could ultimately lead to specific means of interfering with or even reversing these malignant processes.