Dr. Seifu, Daniel (PhD, Assoc. Prof.)Sime, Tariku2020-03-232023-11-292020-03-232023-11-292019-01http://etd.aau.edu.et/handle/123456789/21224Background: Breast cancer (BC) is a type of cancer that develops/grows in breast tissues. It is one of the leading causes of death among women worldwide. Breast cancer is the most frequent cancer and the second leading cause of cancer death among women in industrialized countries. Although it is curable if diagnosed and treated appropriately at an early stage of the disease, diagnosis remains a challenge to the clinicians. The value of current histological prognostic indicators in predicting the course of the disease is weak and reliable markers are still lacking. Therefore, these gaps have led to significant interest in the quest for minimally invasive markers that are sensitive enough to detect early the presence of tumours in patients but not in healthy tumour-free individuals. Objective: was to investigate the capability of circulating microRNAs in serum to discriminate breast cancer patients from healthy controls. Methods: The study was conducted from June 2017 to August 2018 at Tikur Anbessa Specialized University Hospital.A case control study design was conducted involving 50 participants (25 cases, 25 controls). Five milliliter of blood samples were collected and serum was separated from each patient and healthy controls. miRNAs were extracted from serum samples and their relative expression levels were determined by quantitative real time PCR. Data were analyzed using SPSS software (version 25.0, Chicago, IL, USA) and Graph pad Prism version 7. After CT values were analyzed using Microsoft Excel 2010, independent t test and one way ANOVA was done to assess significance of the difference between patients and controls. Data were presented as mean ± SD. Values were considered statistically significant when Pvalue was less than 0.05. Results: We reported that breast cancer specific circulating miRNAs level showed significant difference in breast cancer patients as compared to healthy controls. The expression level of miR-21 and miR-195 were significantly higher (P=0.003, P=0.042 respectively) in serum of breast cancer patients than healthy controls. While there was no significant difference in expression of miR-145 and miR-130b.Furthermore we showed that miR-21 and miR-195 expression level were higher in surgical operated breast cancer patients. Conclusion: Circulating miR-21 and miR-195 are potential breast cancer biomarkers for breast cancer.en-USBiomarkers, Breast cancer, Clinicopathological, Micro RNAThesis