ABSTRACT
Due to the importance of arginase enzyme in different malignant disorders, the purpose of the present study was to determine and compare the arginase activity in cancerous cells and their normal and benign counterparts. The tissue arginase activity level was evaluated in 30 females with breast cancer, in 6 females with benign breast disease and in 9 healthy control subjects. The arginase activity levels were significantly increased in malignant breast tissues in comparison to healthy ones, while the difference did not reach the level of significance in comparison to benign breast diseased tissues. Patients with advanced stage showed insignificantly higher arginase activity compared to those with early stage. In addition, estrogen receptor negative tumors showed insignificant higher arginase activity levels compared to estrogen receptor positive tumors. Moreover, tissues of premenopausal patients showed lower activity levels of arginase compared with those of posrmenopausal ones. Meanwhile, patients with bad prognosis revealed insignificantly higher activity levels of arginase compared to those with good prognosis. It could be concluded that tissue arginase activity seems to be involved in the biological behasiour of breast cancer and its determination in cancerous tissues could predict its outcome