Differences in the fractional composition of cytoplasmic RNP particles in Zajdela ascites hepatoma cells and the liver cells of animals with tumors

Abstract

The relative content of poly(A)-RNA in the cytoplasm is higher in cells of Zajdela's ascites hepatoma and of the liver of rats with tumors than in normal rat liver cells. Another distinguishing feature of the tumor cells (and also, to a lesser degree, of the liver cells of animals with tumors) is a change in the ordinary ratio between polyribosomes and monoribosomes (and, correspondingly, between mRNP particles and informosomes) for normal liver cells in favor of the latter, indicating the occurrence of definite changes in their protein-synthesizing apparatus. According to some of the indices investigated, cells of tumor-bearing animals occupy an intermediate position between normal and tumor cells.