The influence of zinc status on the anti-Lewis lung tumour activity of cisplatin and gallium.

Treatment of C57/BL mice with either cisplatin or gallium nitrate inhibited the growth and metastasis of the Lewis lung tumour and these anti-tumour agents also lowered the zinc levels of some tissues. Nutritional zinc deficiency or the deficiency arising from treatment with the chelating agent, penicillamine, also restricted tumour growth. Although the anti-tumour activity of cisplatin was enhanced in zinc-deficient mice, many of these animals died before sacrifice 14 days after tumour inoculation. The results indicate that zinc status could have considerable bearing on the therapeutic index of the mental-containing anti-cancer drugs.