PROLIFERATION KINETICS OF AN EXPERIMENTAL ASCITES TUMOUR OF THE MOUSE

ABSTRACT The cell cycles of an experimental ascitic tumour of the C3H mouse (NCTC 2472) were determined at various times after the intraperitoneal injection of 10 6 cells. It was found that, contrary to results in solid NCTC 2472 tumours, obtained with the same NCTC cells, the duration of the cell cycle and its phases lengthened with the age of the tumour while the growth fraction remained relatively constant. G 1 was the first phase to lengthen, while later T s and T G2 increased also. The amount of DNA per cell was determined by cytospectrophotometry. This method provides data on the evolution during growth of the relative number of cells in each phase of the cell cycle.