Binding of an antitumor platinum compound to cells as influenced by physical factors and pharmacologically active agents.

' Aided by Research Grant CA-11811 from the NIH and by research funds from the United States Veterans Administration. 2 The abbreviations used are: c/s-Ptll, cw-dichlorodiammineplatinum(H) (NSC 119875); c/s-PPC, m-dichloro(dipyridine)platinum (II); EATC, Ehrlich ascites tumor cells; TCA, trichloroacetic acid; HN2, nitrogen mustard; DMSO, dimethyl sulfoxide; MEM, Eagle's minimum essential medium with Hanks' balanced salt solution; NaCl-C-lu, 0.9% NaCl solution, 0.2% with respect to glucose; PO4, 0.067 M sodium-potassium phosphate buffer; PO.,-Glu, PO4, 0.2% with respect to glucose; CCNU, H2-chIoroethyl)-3-cycIohexyl-l-nitrosourea (NSC 79037). Received September 8, 1972; accepted January 2, 1973. compound prompted an earlier study of an organoplatinum congener, c/'s-PPC, which was shown to have pharmacological