Significance of miRNA-192 as a Prognostic Marker in Chronic Lymphocytic Leukemia

Abstract Background Chronic lymphocytic leukemia (CLL) is the most common human leukemia in western world. This disease can arise in two forms, aggressive and indolent, both characterized by the accumulation of incompetent CD5+ B lymphocytes. MicroRNAs (miRNAs): represent a class of small non-coding RNAs (ncRNAs) of 19–25 nucleotide (nt) length, which post-transcriptionally regulate protein expression, impacting on key cellular functions. miRNAs control numerous cellular/molecular processes such as apoptosis, cell proliferation and differentiation. Deregulated expression of miRNAs contributes to the initiation or development of numerous diseases such as cancer. One of these microRNA is miR-192 which has been suggested to be a positive regulator of p53 (a tumor suppressor gene) and its expression is deregulated in biological samples of cancer patients. Objective To evaluate miRNA-192 as a prognostic biomarker in CLL patients, correlate miRNA-192 expression levels to p53 gene in CLL and find out the association between miRNA- 192 and p53 genes expressions and prognostic criteria of CLL. Methods The present study was conducted on 40 newly diagnosed CLL patients who attended the Hematology outpatient clinic-Ain Shams University hospital during the years from 2018 to 2019 and were included in the study in addition to ten healthy subjects. Quantitation of plasma miR-192 and P53 expression levels were done by real-time quantitative polymerase chain reaction. Results A significant statistical association between poor patients’ outcome and advanced clinical Rai staging together with unfavorable cytogenetic profile was found. Moreover, significant statistical association was also observed in patients with poor outcome expressing low levels of miRNA-192 with p value (P = 0.00) and increased levels of P53. miRNA-192 expression levels in our work were significantly lower in patients with lymphadenopathy and in patients with unfavorable cytogenetic profile. However, it was significantly higher among patients with good prognosis in comparison to patients with worse one. Conclusion miRNA-192 expression levels was significantly correlated with some standard prognostic factors as TLC, Hb &insignificantly with platelets, P53 expression level and favorable cytogenetic profile indicated that circulating miR-192 can serve as non-invasive biomarker that can be used for predicting prognosis and monitoring of therapy in CLL patients.