Upregulation of miRNA-17 and miRNA-19 is associated with unfavorable prognosis in patients with T-cell lymphoblastic lymphoma.

Lymphoblastic lymphoma is an aggressive subtype of non-Hodgkin lymphoma. Identification of prognostic factors for these patients, especially for patients with T-cell lymphoblastic lymphoma (T-LBL), remains a challenge. This is largely due to the relative rarity of the disease and lack of adequate samples for biological research. T-LBL is more common in Asia than in Western countries. In an attempt to explore novel prognostic markers for T-LBL, we conducted retrospective study of archived diagnostic specimens from 57 Chinese patients with well-defined diagnosis of T-LBL. Using quantitative real-time reverse transcription-PCR, we analyzed miR-17 and miR-19 expression levels in formalin-fixed and paraffin-embedded lymph node specimens from these patients, together with reactive lymph node controls. We correlated molecular findings to patients' immunophenotype and clinical follow-up information. MYC protein expression was also evaluated in these patients. We found that miR-17 and miR-19 levels were concordant and upregulated in T-LBL in comparison with controls. Statistical analysis showed that higher expression of miR-17 and miR-19, and positive MYC protein results were associated with a shorter overall survival of T-LBL. In addition, miR-17 and miR-19 appeared to be independent prognostic factors for T-LBL. We demonstrate here that upregulation of miR-17 and miR-19 correlates with poor clinical outcome of T-LBL, indicating that miR-17 and miR-19 may be considered as potential unfavorable prognostic markers for T-LBL.