10Sep 2017

A NEW METHOD FOR DETERMINATION THE ACTIVITY OF 25-HYDROXYCHOLESTEROL 7-ALPHA-HYDROXYLASE (CYP7B1) IN TISSUES OF WOMEN WITH BREAST TUMORS USING ELISA TECHNIQUE WITH SOME MODIFICATION.

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Background:CYP7B1 expression has been decreased in ER-positive tumors compared with normal breast tissues. Tumors get 27-HC from the blood and also convert cholesterol into 27-HC within the own cells. In addition, there are greater 27HC levels in tumor samples compared with controls. Furthermore, survival of cancer patients is markedly poor for patients with low versus high tumor CYP7B1 expression. Objective:Attempt to use a simple and new method for determination the activity of CYP7B1 in tissues of women with benign and malignant breast tumors using ELISA technique with some modification. Methods:This case control study was conducted on sixty patients with breast diseases were divided into three group, group I contained twenty patients with benign breast diseases, group II consisted of twenty premenopausal patients with breast cancer. Group III comprised twenty postmenopausal patients with breast cancer with the mean age and standard deviation (25.25? 7.87, 38.65? 6.28, 58.5? 7.02 years). Oxysterol 7α-hydroxylase (CYP7B1) were measured in tissues by instrument ELISA technique with some modification. Result:The activity of CYP7B1 in tissue homogenates of women with breast tumors are increased when the time increased to limited time (1,5,10,15 min) then decreased when the time increasing to 30 minute. This activity was increased in benign compared with pre and postmenopausal woman with breast cancer Conclusions:A simple and new method for determination of the activity of 25-hydroxycholesterol 7-alpha-hydroxylase (CYP7B1) in tissue homogenates of women with breast tumors was developed using ELISA technique.


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[Zahraa Kadhim Mohammed, Hassan H. AL-Saeed and Anees K. Nile. (2017); A NEW METHOD FOR DETERMINATION THE ACTIVITY OF 25-HYDROXYCHOLESTEROL 7-ALPHA-HYDROXYLASE (CYP7B1) IN TISSUES OF WOMEN WITH BREAST TUMORS USING ELISA TECHNIQUE WITH SOME MODIFICATION. Int. J. of Adv. Res. 5 (Sep). 76-79] (ISSN 2320-5407). www.journalijar.com


Zahraa Kadhim Mohammed


DOI:


Article DOI: 10.21474/IJAR01/5302      
DOI URL: http://dx.doi.org/10.21474/IJAR01/5302