Breast cancer (BC) is the most common cancer amongst Egyptian women and worldwide. Micro-RNA-21 (miR-21), on chromosome 17q21.3, is one of the most up-regulated microRNAs in cancer that silences multiple target genes involved in cancer-signaling pathways. The aim of this study was to assess the correlation between numerical aberrations of chromosome 17 and the miR-21 expression profile in BC tissues in female Egyptian patients.Methods
The study included 37 female patients with sporadic primary breast carcinoma, their age ranged from 31 to 65 years. Fresh breast tissue specimens were evaluated for miR-21 expression levels using reverse transcription-polymerase chain reaction technology and cytogenetic fluorescent in situ hybridization analysis for chromosome 17 aneusomy.Results
miR-21 was up-regulated 12.9-fold in BC tissues compared with normal adjacent tissue. Over-expression was significantly associated with several clinico-pathologic characteristics; as higher tumor grade, more tumor size, advanced stage, and poor prognostic index. In addition, chromosome 17 monosomy and trisomy were observed in 21.6 and 5.4 % of BC patients, respectively. However, the large majority (73 %) of patients had heterogeneous cell populations. Chromosome 17 copy number heterogeneity in cell populations were significantly associated with advanced clinical stage and higher miR-21 expression profile in BC tissues.Conclusion
Chromosome 17 aneusomy and miR-21 expression are positively correlated and can potentially serve as prognostic markers in BC.