5593 - Prognostic value of microRNA-21/ Ki-67 in non- Hodgkin`s lymphoma; NCI experience

Background

MicroRNA-21 (miR-21) is a small non-coding RNA that inhibits target genes expression thus affects tumorigenesis. Ki-67 is a nucleolar protein antigen in proliferating cells.Ki-67 expression is highly correlated with the proliferation rate. Immunohistochemical assay (IHC) of Ki67 antigen in paraffin section (Ki67 proliferative index) represents the active growth fraction of the tumor. We aim to evaluate the diagnostic and prognostic value of miR-21 and ki-67 as a potential biomarker of non- Hodgkin`s lymphoma (NHL).

Methods

We prospectively enrolled NHL patients (2017-2018). Serum MiR-21 and tissue Ki-67 were assessed with RT- PCR and IHC of lymph node biopsy respectively. The primary outcomes were to identify overall survival (OS), and progression free survival (PFS), while the secondary outcomes were to identify the associations between different variables and miR-21 and Ki-67. Spearman’s correlation was used and expressed as correlation coefficient (r). Kaplan-Meier survival curves were used and compared using Log-rank. Cox regression was used to identify the independent predictors of survival.

Results

80 patients were recruited with median age of 56.5 years (Inter-quartile range: 47- 64.8), 50% were males. DLBCL represented 80%. 53/73 known responses (72.6%) were responders (partial or complete response). Higher miR-21 was noticed among patients with B symptoms (r = 0.304, P = 0.006), higher extra-nodal number (r = 0.341, P = 0.002), stage IV (r = 0.221, P = 0.048), LDH (r = 0.287, P = 0.010), BMB infiltration (r = 0.230, P = 0.040), international prognostic index (IPI) (r = 0.511, P < 0.001). Lower miR-21 was noticed among females (r= -0.258, P = 0.021). Higher Ki-67 was noticed among old age (r = 0.330, P = 0.005), diffuse large B cell lymphoma (DLBCL) vs other diagnoses (r = 0.315, P = 0.008). On multivariable analyses, Ki-67 was associated with worse OS (HR 1.033 (95%CI 1.002-1.066), P = 0.038) and PFS (HR 1.032 (95%CI 1.010-1.054), P = 0.004).

Conclusions

Plasma miRNA-21 may be employed as valuable non-invasive diagnostic marker in NHL. High miR-21 was noticed among high LDH, advanced stages and high IPI patients. Ki-67 is a significant predictors of overall survival, and progression free survival in NHL. Higher Ki-67 was noticed among elderly and DLBCL.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.