Identification of MiR-125a as a Novel Plasma Diagnostic Biomarker for Chronic Lymphoblastic Leukemia

Background: Chronic lymphocytic leukemia (CLL) is a type of malignancy in which the bone marrow makes too many lymphocytes. MicroRNAs (miRNAs) are endogenous short (~22-nucleotides) non-protein-coding regulatory RNA molecules with key roles in cellular and molecular processes linked to different cancers including CLL. Re-cently, some investigations have demonstrated that miR-125a downregulation is correlated with the expression of P53, NRG1 and ERBB2. Methods: In this study, samples including 38 patients with CLL and 25 healthy individuals were collected. We used quantitative real-time PCR (qRT-PCR) to assess the expression of miR-125a in plasma of the CLL patients in comparison with healthy controls. Moreover, we used the Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway analysis on miR-125a targets in the DAVID database in order to investigate the potential role of miR-125a in cancer pathways. MiR-125a exerted a variety of roles in the cancer pathway via downregulating target genes including ERBB2. Results: The expression of miR-125a dramatically decreased (~2-fold) in the patients with CLL compared with the healthy controls (p = 0.03). Furthermore, overexpression of miR-125a was associated with different CLL staging and B symptoms (all at p < 0.05). The KEGG pathway enrichment analysis demonstrated the eight statistically related KEGG signaling pathways with miR-125a targetome. Conclusions: The results suggested that the miR-125a expression level could be a novel potential biomarker for CLL prognosis.