miR-888 and E-Cadherin Levels in Ductal Carcinoma Breast Cancer as Possible Cancer-Related Markers.

Background: Cancer occurs due to genetic or epigenetic factors. Breast cancer (BC) is the most common cancer among females and is considered one of the leading causes of cancer death worldwide. Epigenetic biomarkers have proven to be important in cancer management. Methods: E-cadherin gene expression and its associated regulatory microRNA, miR-888, were studied in 60 ductal carcinoma BC patients compared with normal controls using real-time Reverse Transcription Polymerase Chain Reaction. In addition, the association of the gene and microRNA expression with hormone receptors and other clinicopathologic characteristics were assessed. The correlation between plasma and tumor miR-888 expression was studied to evaluate its potential as a marker of noninvasiveness. Results: The results showed a significant increase in expression of miR-888, and a decrease in E-cadherin expression in tumor tissues compared with normal controls. The miR-888 and E-cadherin mRNA levels showed an inverse correlation. The overexpression of miR-888 in both tumor and plasma and downregulation of E-cadherin were particularly prominent when there was nodal involvement and distant metastasis status as we well as being significantly associated with higher disease stages and triple-negative tumor hormone receptor status. The Kaplan-Meier survival curves indicated that overall survival was significantly poor in BC patients with higher miR-888 and lower E-cadherin expression. Conclusions: Our study indicated that elevated eXpression of miR-888 may be a negative prognostic factor in breast cancer.