Integrated analysis on mRNA microarray and microRNA microarray to screen immune-related biomarkers and pathways in...

Myelodysplastic syndrome (MDS) is a haematopoietic malignancy that is characterized by a heterogeneous clinical course and dysplastic maturation of blood lineages. Immune dysregulation has gained attention as one of the fundamental mechanisms responsible for the development of MDS. This study aimed to screen immune-related biomarkers and pathways in MDS.

Differentially expressed mRNAs (DE-mRNAs) and differentially expressed microRNAs (DE-miRNAs) in different subtypes of MDS were sourced from the Gene Expression Omnibus (GEO) database. DE-mRNAs were intersected with immune-related gene sets to collect immune-related mRNAs, which were put into the Search Tool for the Retrieval of Interacting Genes (STRING) to construct protein-protein interaction (PPI) networks. Target mRNAs of DE-miRNAs were predicted using the miRDB database and intersected with screened immune-related mRNAs to construct miRNA-mRNA interaction networks. Topological analysis of constructed networks was applied to screen key molecules, which were assessed in independent datasets and previous literature. Enrichment analysis was applied to screen dysregulated pathways in MDS.

Screened key mRNAs were mainly from the Toll-like receptor (TLR) family, including TLR2, TLR4, TLR7, and from the chemokine family, including C-X-C motif chemokine ligand 10 (CXCL10) and CC chemokine ligand 4 (CCL4). Cytokine-cytokine receptor interactions were among the major pathways in the enrichment analysis results. Hsa-miR-30b, hsa-miR-30e and hsa-miR-221 were validated as key miRNAs and modulate cytokine-cytokine receptor interactions by targeting immune-related mRNAs.

Dysregulated cytokines reflect the immunization status in MDS. Immune-related miRNA-mRNA interactions not only provide a perspective to our understanding of immunologic derangement in the pathogenesis of MDS but also provide new therapeutic opportunities.