Destructive Action of Human Cancer Extracts on Red Blood Cells in vitro.

Abstract

Expts. reported in this study suggest that extracts prepared from human cancer occasionally agglutinate, and frequently hemolyze human red blood cells in vitro. These phenomena, but particularly the hemolysis, become evident only after prolonged incubation of the tumor extracts with the red blood cells at 37[degree]C. The agglutination is evident after 24 hrs. of incubation or earlier; the hemolysis requires 48 hrs. of incubation. Heating of the tumor extracts for 30 min. to 56[degree]C prior to mixing them with the red blood cells, destroys their ability both to agglutinate and to homolyze the erythrocytes. Control expts. were made with extracts prepared from various normal human tissues; with insignificant exceptions the results of these control tests were negative. The conclusion appears justified that human cancer cells either secrete or liberate a thermolabile substance which, in vitro at least, exerts a slow-acting but destructive influence on human erythrocytes. The possible relationship of anemia, so frequently observed in cancer, and the destructive action of the tumor on red blood cells, is discussed.