# The Role of microRNAs as Potential Biomarkers in Diffuse Large B-Cell Lymphoma

## TL;DR

This paper reviews how microRNAs could serve as biomarkers for diagnosing and predicting outcomes in diffuse large B-cell lymphoma.

## Contribution

The paper highlights the diagnostic and prognostic potential of specific microRNAs in DLBCL.

## Key findings

- Oncogenic miRNAs like miR-155 and miR-21 promote DLBCL progression and therapy resistance.
- Tumor-suppressive miRNAs such as miR-34a and miR-124-3p inhibit oncogene activity and are linked to better outcomes.
- Loss of tumor-suppressive miRNAs is associated with adverse clinical outcomes in DLBCL.

## Abstract

Diffuse large B-cell lymphoma (DLBCL) is the most common and clinically aggressive subtype of non-Hodgkin lymphoma (NHL). While novel therapies such as rituximab and polatuzumab vedotin have led to improved outcomes, approximately 35% of patients eventually develop relapsed or refractory disease. MicroRNAs (miRNAs), a class of endogenous single-stranded RNAs approximately 22 nucleotides in length, play a pivotal role in the regulation of gene expression at the post-transcriptional level through interactions with complementary target RNAs and contribute significantly to the development, progression, and treatment response of DLBCL. Oncogenic miRNAs, such as miR-155, miR-21, and the miR-17–92 cluster, promote proliferation, survival, immune evasion, and therapy resistance by modulating pathways including PI3K/AKT, NF-κB, and MYC. Conversely, tumor-suppressive miRNAs such as miR-34a, miR-144, miR-181a, and miR-124-3p inhibit oncogene activity and enhance apoptosis, with their loss often associated with adverse outcomes. Among these, miR-155 and miR-21 are particularly well studied, playing central roles in both tumor progression and remodeling of the tumor microenvironment. This review summarizes current evidence on the biological and clinical relevance of miRNAs in DLBCL, emphasizing their diagnostic and prognostic potential.