The Significance of Abnormal Mitosis in the Development of Malignancy

Abstract

Cell division normally takes place by means of bipolar mitosis which results in the formation of two daughter cells, each with an equal complement of chromosomes derived from the parent cell. Arnold (1879) was the first to observe that the cells of malignant tissues multiplied by the same process. von Hansemann (1890) reported that many of the mitotic divisions in carcinomata did not result in the usual equal distribution of chromosomes to the two daughter cells and also noted many instances of multipolar mitoses. He ascribed great significance to his findings and, after studying many carcinomata, concluded that asymmetrical mitosis constituted a definite diagnostic characteristic of carcinomata. Stroebe (1892) was able to confirm the presence of asymmetrical mitosis in carcinomata, but he also described its occurrence in sarcomata and in normal regenerating and inflammatory tissues. He concluded that von Hansemann9s theory was untenable. True asymmetrical mitosis he considered to be a rare process frequently simulated by the false pictures that are created by cutting a dividing cell with the microtome knife. Abnormal chromosomal behavior in tissue cultures has been induced by subjecting the living cell to various substances. M. R. Lewis (1935) found that the dye, fluorescent X, caused lagging of chromosomes, with unequal distribution to the daughter nuclei. She was also able to disturb the mitotic figures by means of heat and hypotonic and hypertonic solutions. The normal course of mitosis in tissue cultures has also been affected by means of ether and ammonia (Rosenfeld, 1932) and by radium (Whitman, 1933).