WATER SOLUBLE NITROSYL IRON COMPLEXES WITH NATURAL LIGANDS -A NEW FAMILY OF ANTI-TUMOR AGENTS FOR MONOTHERAPY OF CANCER ▼ Nitrosyl [2Fe-2S] complexes comprising functional sulfur-containing ligands, synthetic models of natural depots of NO in cells, have been proposed as hybrid preparations for monotherapy of solid tumors. Sulfur-containing ligands are known to be reversible inhibitors of synthesis of cell DNA and are widely used in biochemical and medical experiments to suppress the growth of solid tumors of different genesis. As the other component of a hybrid molecule, the NO group is a key signal molecule controlling the tumor growth. Special award of Moscow International Salon "Archimedes-2009" The best invention for protection and salvation of human beings" ▼ Advantages of the preparation: : high stability in the crystalline state; 100% water solubility; durable NO-donor activity in physiological media; high cytotoxicity on lines of human tumors of different genesis; low toxicity and high anti-tumor activity on laboratory animals. ▼ Cytotoxic activity of the nitrosyl iron complex with cysteamine on lines of human tumor cells № Cell line IC50, мкM 1 Erythroblastic myeloleukemia К562 17 2 Large intestine carcinoma LS174T 55 3 Ovarian carcinoma SKOV3 43 4 Mammary gland carcinoma SKBR3 15 5 Immortalized kidney cells А293 34 ▼ Anty - tumor activity of the nitrosyl iron complex with cysteamine on experimental tumors of mice ► Criteria of chemotherapy efficiency: - inhibition of tumor growth, ( %); - longer lifetime of animals as compared with that of reference ones (LLT, %). ► The complex was introduced for 5 days at - 0,1÷5 mg/kg. Dose mg/kg Days after completion of treatment LLT, % Death from toxicity 1 7 10 14 12 Inhibition of LLC growth, % 0.1 29 43 43 34 32 -2 0/8 1 63* 52* 53 41 46 17 0/8 2 64 20 30 18 - -1 0/7 3 83* 51* 47 18 - 1 0/7 4 86* 67* 61* 25 - 7 0/7 5 84* 56* 36 35 38 -12 3/8 Inhibition of Ca-755 growth, % 2 40 22 14 6 +2 3 0/8 3 29 16 +13 +10 +17 3 0/8 4 23 71 76 63 64 66 1/8 5 29 62 75 77 72 26 2/8 Inhibition of B-16 growth, % 2 26 15 13 - - -1 0/7 3 24 19 11 - - 6 0/7 4 0 9 +11 - - -3 1/7 5 26 +1 +5 - - 0 2/7