Platinum antitumor compound

The reaction of sulfur-containing biomolecules with platinum antitumor compounds, thereby preventing binding to the critical DNA target, is a possible mechanism of inactivation and is supported by numerous studies. Thus, glutathione (GSH, a cysteine-containing tripeptide see also Fig. 6), which is the predominant intracellular thiol and is present in concentrations varying from 0.5 to 10 mM, is able to inhibit the reaction of DNA with [Pt(en)Cl2] (74) and with cis-Pt (75, 76). It has also been observed that the presence of cysteine can inhibit the reaction between cis-Pt and d-Guo (77). Furthermore, the antitumor activity of cis-Pt was proved to be inhibited by coadministered methionine (78, 79) and even a bis-adduct between cis-Pt and methionine has been isolated from the urine of patients (80). 

Miscellaneous. Reduction of a palladium salt by CO is the basis of a visual test for ambient carbon monoxide (227). Palladium compounds are used as photographic sensitizers (228). The low dimensional mixed valence compound Csq 3[Pd(S2C2(CN)2)] 0.5H2O behaves as a semimetal at room temperature (229). Palladium compounds isostructural with potent platinum antitumor compounds have poor antitumor activity (230). 

Todd, R.C., Lippard, S.J. Inhibition of transcription by platinum antitumor compounds. Metallomics 1, 280-291 (2009)... 

Colvin M. Alkylating agents and platinum antitumor compounds. In 91. 

A selection of such compounds has been redrawn in Fig. 4.4. Reviews on this matter are available.An example of our own work deals with the binding of platinum-antitumor compounds to DNA, and the resulting distortion of the DNA and its biological consequences will be discussed in some detail in the next section. 

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