title: miRNA as potential biomarkers of breast cancer in the Lebanese population and in young women: a pilot study.
abstract: Relative to western populations, the percentage of women diagnosed with breast cancer at a young age in Lebanon is high. While the younger age of the Lebanese population compared to the West certainly contributes to this difference, potential genetic, reproductive and/or biological factors likely play an important role. The objective of this study is to investigate the contribution of miRNAs in this setting through the analysis of the expression of five reported dysregulated miRNAs, miR-148b, miR-10b, miR-21, miR-221, and miR-155 in 20 normal and 57 cancerous breast tissues from Lebanese breast cancer patients. After finding their relative expression by quantitative reverse transcription real time PCR, the results were analyzed with respect to the patients' clinical and histopathology presentations. Compared to normal breast tissues, significant upregulation of miR-155, miR-21 and miR-148b, notable downregulation of miR-10b and non-significant expression of miR-221 were observed in tumor tissues. Moreover, miR-10b was significantly underexpressed in estrogen/progesterone receptor (ER/PR) negative tumors relative to ER/PR positive tumor tissues. miR-155 was also significantly overexpressed in postmenopausal patients and in those of age at diagnosis greater than 40 years old as well as in PR negative or in human epidermal growth factor 2 (Her2) positive tissues. This study is the first one to report miRNA expression patterns in Lebanese breast cancer patients. We found that differential miRNA expression in breast cancer could be variable between Lebanese and Western populations. miR-10b was positively correlated with the ER and PR status and miR-155 could be a noteworthy biomarker for the menopausal state, age at diagnosis, PR and Her2 status. Hence, miRNA can be used as biomarkers for early breast cancer detection.
authors.affiliation: Department of Biology, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon.
authors.forename: Farah J
authors.initials: FJ
authors.lastname: Nassar
authors.affiliation: Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon.
authors.forename: Maya
authors.initials: M
authors.lastname: El Sabban
authors.affiliation: Department of Pharmacology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon.
authors.forename: Nathalie K
authors.initials: NK
authors.lastname: Zgheib
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, American University of Beirut, Beirut, Lebanon.
authors.forename: Arafat
authors.initials: A
authors.lastname: Tfayli
authors.affiliation: Department of Pathology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon.
authors.forename: Fouad
authors.initials: F
authors.lastname: Boulos
authors.affiliation: Department of Pathology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon.
authors.forename: Mark
authors.initials: M
authors.lastname: Jabbour
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, American University of Beirut, Beirut, Lebanon.
authors.forename: Nagi S
authors.initials: NS
authors.lastname: El Saghir
authors.affiliation: Department of Biology, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon.
authors.forename: Rabih
authors.initials: R
authors.lastname: Talhouk
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, American University of Beirut, Beirut, Lebanon.
authors.forename: Ali
authors.initials: A
authors.lastname: Bazarbachi
authors.affiliation: Department of Experimental Therapeutics, Division of Cancer Medicine, University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America.
authors.forename: George A
authors.initials: GA
authors.lastname: Calin
authors.affiliation: Department of Anatomy, Cell Biology and Physiological Sciences, Faculty of Medicine, American University of Beirut, Beirut, Lebanon.
authors.forename: Rihab
authors.initials: R
authors.lastname: Nasr
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000235:genetics*; D001940:Breast / Q000473:pathology; D001943:Breast Neoplasms / Q000453:epidemiology / Q000235:genetics*; D015536:Down-Regulation; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D005819:Genetic Markers / Q000235:genetics; D006801:Humans; D007861:Lebanon / Q000453:epidemiology; D035683:MicroRNAs / Q000096:biosynthesis / Q000235:genetics*; D010865:Pilot Projects; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics; D011960:Receptors, Estrogen / Q000235:genetics; D011980:Receptors, Progesterone / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015854:Up-Regulation
chemical_list: D014408:Biomarkers, Tumor; D005819:Genetic Markers; D035683:MicroRNAs; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human