of Metastases

A comparative study of stickiness of tumor cells to glass surfaces was undertaken with the use of three strains of rat ascites hepatoma, All 13, All 130, and All 7974. Stickiness was measured by calculating the percentage of cells clinging to a glass surface of the calculating plate after it was washed with salt solution. A significant difference was observed in the cell stickiness among these three strains. All 13 showed the most active stickiness, All 130 moderate, and All 7974 the least active. These results indicate that cell stickiness is inversely correlated with the ad hesiveness between cells in the above tumors. When these three tumor strains were inoculated intravenously, the most active strain with respect to cell stickiness caused the largest number of metastatic nodules in the lung. The same result in frequency of lung metastasis was also obtained with intraperitoneal inoculation of each tumor. Such a correlation between metastatic frequency and cell stickiness suggests that the cell stickiness may be an important property of the cell surface responsible for metastatic spread of tumor cells via blood vessels. In order to study the nature of stickiness, chemical treatments of tumor cells in vitro were undertaken with the use of Ehrlich ascites carcinoma, All 13, and Yoshida sarcoma. It was found that the stickiness of tumor cells was decreased by treatment with protamine sulfate and trypsin, whereas stickiness was increased by treatment with Tween-80. Significant effects on stickiness could not be observed with polyvinyl sulfate, sodium deoxycholate, calcium chloride, and disodium versenate. Further more, in acid medium, cell stickiness was significantly decreased, while in alkaline me dium it was increased. Based on these results, stickiness of tumor cells to glass was discussed.