[Arginine as a crucial amino acid in carcinogenesis and tumor growth].

Arginine, a cationic semi-essential amino acid, is involved in numerous pathways of human metabolism. It serves as a precursor for the biosynthesis of proteins and also of ornithine, polyamines, nitric oxide, proline, glutamate, glutamine, creatine, agmatine and dimethylarginines. Arginine is conditionally essential amino acid as it is necessary under phase of growth (in children) and in adults under some pathological conditions, as well as during recovery after catabolic diseases. There is a growing interest in the role of arginine in cancerogenesis, since this amino acid has turned out to be absolutely essential for growth of neoplastic cells. It also plays a crucial role in biosynthetic pathways that significantly influence carcinogenesis and tumor biology. They include synthesis of polyamines and nitric oxide, important molecules, which may be synthesized solely from arginine. These findings have resulted in first clinical trials on arginine deprivation in therapy of some arginine-dependent (auxotrophic) tumors. The present article is focused on recently recognised role of arginine in tumor development, including processes associated with carcinogenesis, such as apoptosis and angiogenesis.