Arrest and metastasis of blood-borne tumor cells are modified by fusion of plasma membrane vesicles from highly metastatic cells

Abstract

B16 mouse melanoma sublines in culture spontaneously shed intact plasma membrane vesicles. These vesicles can be fused with the plasma membrane of cells from homologous and heterologous B16 sublines by using polyethylene glycol and phytohemagglutinin-P. Fusion of vesicles from a highly metastatic subline (F10) that localizes exclusively in the lung with cells from a poorly metastatic subline (F1) significantly increased the ability of F1 cells to become arrested in the lung and form metastases in this organ. In contrast, fusion of F1 vesicles with F10 cells did not alter the ability of vesicle-modified cells to localize in the lung or form lung metastases. F10 vesicle-modified F1 cells reverted to their original arrest behavior and metastatic capacity after removal of F10 vesicle components from the plasma membrane. The changes in the arrest and metastatic behavior of F10 vesicle-modified F1 cells were highly highly specific. Vesicles from other B16 sublines that are poorly metastatic and show limited localization in the lung (F1, FLLr, and F10Lr) did not modify the arrest behavior and metastatic capacity of FU cells. These results suggest that the differences in the abilities of the F1 and F10 sublines to localize in the lung are determined by differences in cell surface properties.