Microscopical observations of the effects of tumour‐inhibitory and non‐inhibitory samples of gum tragacanth on Landschütz ascites tumour cells

Abstract

SYNOPSISThe periodic acid‐Schiff (PAS) technique of Hotchkiss (1948) has been used to follow the action of tumour‐inhibitory, native gum tragacanth on cells of the Landschütz mouse ascites tumour in vivo. The results have been compared with those of various non‐inhibitory modified tragacanth samples and of gum karaya (kutira grade), and have been related to earlier studies of changes in mitosis and in cell permeability after treatment of the tumour with the same gums. PAS‐stained particles are observed surrounding the tumour cells and attached to their surfaces as early as 10 minutes after treatment with inhibitory gum and no similarly stained material, additional to that in control cells, is detected within the treated cells until 5 to 6 hours after commencement of treatment.Non‐inhibitory gum samples formed PAS‐stained particles of different size and shape which were not bound to the surface of the tumour cell. No additional PAS‐stained material appeared within the cells after treatment with these samples.It is concluded that the active gum causes growth inhibition by direct action at the surface of the tumour cell.