MODE OF ACTION OF CHEMICAL CARCINOGENS
Alexander Haddow · British Medical Bulletin · 1946
7 Energetics of the malignant transformdtion 8 Relation to the viruses of chicken sarcoma References Sufficient has already been said in a previous paper1 (Haddow & Kon, 1947) to indicate the nature, number and great variety of the chemical carcinogens. Several hundreds of these are at present known, and while the list is almost certainly far from complete, it is natural that less attention should now be paid to descriptions of the carcinogens alone, and progressively more to their mode of action. ~ • \\BMB 9«T] Hence, the problems of major importance which must now concern us are rather the nature of the structural rela-tionship between carcinogens of one chemical class and those of another, the extent to which any such.com-munity of structure may signify a common principle of action, and finally, the nature of that action itself by which the biological change, from the normal to the malignant state, is achieved. Before proceeding, it.may be nofcd how comparatively little in the way of correlation has been obtained, at least until very recently, by the use of purely physical methods, how fertile in contrast have been the suggestions arising from the chemical and biochemical attack, and how consonant these are with independent evidence from an exclusively physiological or biological approach, which has in itself been able to establish a practical working hypothesis comprehensive enough to include carcinogens of the most varied types, and apparently sound enough to predict the activity of an entirely new class—the aminostilbenes. 1. Physical Properties So ' far as physical properties are concerned, the great majority of all chemical carcinogens are virtually insoluble in water, although soluble in lipoids and to some extent in body-fluids such as serum and bile; but no relation exists, directly at any rate, between the greatly varying degrees of such solubility and carcinogenic action. For the polycyclic hydrocarbons, no specific differences have been disclosed