THE ENORMOUS chemical heterogeneity of histologically similar tumors has been noted by Heidelberger,1 Danielli,2 Knock,3 and others. Nowhere is this seen more clearly than in the variability of response of histologically similar human tumors to sulfhydryl inhibitors.4,5 Such variability would be expected from profound influence exerted by intimate submicroscopic chemical milieu on reactions of functional groups like sulfhydryl in cellular protein through steric, coulombic, and entropy effects, for example.6 Investigation of sulfhydryl inhibitors for cancer chemotherapy appears desirable because sulfhydryl-containing7 residual protein bound to desoxyribose nucleic acid (DNA) has been shown by Mirsky and co-workers to be as indispensable to the structure of chromosomes as is DNA itself8 and because sulfhydryl inhibitors preferentially cause blebbing of cancer cells, both in vitro and in vivo. Associated with this preferential blebbing of cancer cells produced by sulfhydryl inhibition can be events of profound cellular significance—