Detection of Xanthine Oxidase IN Breast Cancer

Abstract

Thirty two females with breast cancer were studied .in this study xanthine oxidase levels were compared with normal females .Results obtained in the present study showed that high levels of xanthine oxidase in older age than in lower age . High level of xanthine oxidase was detected in patients having breast cancer and Diabetes Meilltus ,heart diseases, and anemia ,but no change in xanyhine oxidase was detected in breast cancer with hyperytension . key words: xanthine oxidase ,breast cancer.Breast cancer is a type of cancer originating from breast tissues, most commonly from the inner lining of milk ducts or the lobules that supply the ducts with milk(1).The size, stage, rate of growth and other characteristic determine the kind of treatment (2.) Breast cancer may be invasive or noninvasive. Invasive means it has spread from the milk duct or lobule to other tissues in the breast. Noninvasive means it has not yet invaded other breast tissue(3). Xanthine oxidase (XO) is the final enzyme in the degradation of purines. It converts hypoxanthine to xanthine and subsequently to uric acid. Unlike other oxidases. lmmunohistochemical location of XO has been reported its presence in various tissues from various animal species( 4) .Other researcher demonstrated the ubiquitous localization of this cytosolic enzyme in human tissues, such as tongue,esophagus, trachea, sweat glands, mammary glands, small and large intestine, renal tubules skeletal muscle, lung, spleen and liver. It was found that human blood or serum contains XO activity, since high concentration of XO antibodies are present in human sera (5).XO may play a beneficial role by producing superoxide radicals (6). Previous studies suggested a role of XO as an antimicrobial agent (7).. Moreover, it was reported that uric acid, in its normal range,serve as an antioxidant. Therefore, XO serves as a defense mechanism by generating uric acid as well(6).This study was conducted in Iraqi center for cancer research and medical genetic. Thirty two With age range 40-73 years, had breast cancer diagnosed by history, clinical and laboratory findings, and twenty controls with range age 30-75 years old, had no evidence of diseases of diseases. Blood was collected from a forearm vein.Blood samples were allowed to clot at room temperature and serum was separated by centerfugation at 1500g for 10 min. Xanthine Oxidase Assay: Xanthine Oxidase(XO,EC 1.17.3.2). In this assay XO oxidizes xanthine to hydrogen peroxide which reacts with stoichiometrically with OxiRedTM probe to generate color( at lambda=570nm).Since the color intensity is proportional to XO cotent,the XO activity can be accurately measured. 1-Standard curve preparations: It has been added 0, 10, 20 , 30 , 40 , 50 ul of the 0.1mM H2O2 standard,to generate 0 ,1 ,2 ,3 ,4 ,5 nmol/ well H2O2 standard. 2- Sample preparation: 44 ul buffer , 2ul substrate, ,2 ul enzyme mix , 2ul probr. 3-It has been measured the plate immediately (O,D=570 nm) for colorimetric assay. 4 – XO activity = B/(T2-T1Xv) x Sample Dilution Factor = nmol / min/ml = mU/ml Where; B is the amount of H2O2 Generated by XO from standard curve(in nmol). T1 is the time of first reading(A1) (in min ) T2 is the time of second reading (A2)(in min) V is the pretreated sample volume added into the reaction well (in ml ).