LAUSR

Breast cancer has high mortality rates among the women in the Republic of Armenia. It is now evident that nitric oxide plays important roles in various stages of carcinogenesis such as oncogene activation, tumor suppressor genes, modulation of apoptosis and metastasis. Advances in our understanding of the metabolism and molecular functions of arginine alterations in cancer have led to resurgence in the interest of targeting arginine catabolism, as an anticancer strategy. NOS inhibitors have been proposed, as a way to treat cancer. We have been researching the anti-tumor potential of the NOS inhibition by NG-Nitro-L-arginine methyl ester treatment (30 mg/kg/day, i.p.), administered for 5 weeks (parallelly to tumors development, every 3th day) against 7,12-dimethylbenz(a)anthracene induced mammary carcinogenesis in rats. Our treatment model results have shown the inhibition of NOS activity has influenced on development of carcinogenesis, which have been reflected in changes of rats’ tumors size and quantity, mortality rate, in alteration of breast histopathology, in decrease of polyamines, NO and malondialdeide concentrations in blood. Understanding dichotomy of NO has been a great challenge for researchers working in the field of cancer therapy.