A study of the behavior of coal tar on the tissues.

Abstract

In another study Burrows has shown that growth in a tissue depends on a crowding of the cells together and a cutting down of their relative blood supply. It is the direct result of the accumulation of a substance which stimulates the normal metabolism of the cell. This stimulating substance is soluble in the circulating body fluids. He failed to find any direct difference between the cancer cell and the normal cell. The independent growth seen in cancer like the shape and the arrangement of the cells may be directly related to a primary change in the normal orderly arrangement of the cells in the tissues of the body. This growth stimulating substance is liberated in the normal metabolism of the cell. It acts directly to break down the proteins. In excess it causes a complete destruction of the cell. In less concentration it causes growth. Dense masses of cells poor in blood vessels or avenues of escape of this substance, such as cancerous tissues and the tissues of young embryos are rich in this substance. Other tissues cut off from their blood supply but supplied with oxygen accumulate this substance after a latent period which varies indirectly with the immediate cell density of the fragment of tissue being tested. Cancer, as Burrows' studies indicate, is the result of any condition or substance which can cause the formation of a dense mass of cells relatively poor In blood vessels within the organism. This stimulating substance as Burrows has further shown, acts to produce another substance in fixed tissue cells which is an active blood coagulant. This coagulating substance is poorly soluble in the fluids of the body but combines readily with fibrinogen to form fibrin. It flows readily over the surface of body fluids.