miRNA Expression Profiling in Mesenchymal Stromal/Stem Cells Derived from G-CSF Primed Bone Marrows

Regulatory microRNAs (miRNAs) are involved in the molecular control of hematopoiesis and diseases that result from aberrations during this process. Bone marrow (BM) transplantation is a commonly used therapy for patients with certain hematopoietic diseases. Prior to BM transplantation, donors are occasionally treated with granulocyte colony-stimulating factor (G-CSF) to increase the number of hematopoietic stem or progenitor cells in the collected stem cell product. Here we aimed to assess the effects of G-CSF priming on miRNA expression of BM derived mesenchymal stromal/stem cells (BM-MSCs) from healthy donors.

Previously isolated and characterized BM-MSCs from 3 days G-CSF (10 μg/kg/d) treated (n=5) and untreated (n=8) healthy donors were used for miRNA expression profiling with Affymetrix GeneChip 2.0 Array. Following Robust Multi-array Average (RMA) normalization, data analysis was carried out in Partek Genomics Suite software package (Partek Incorporated). Differentially expressed miRNAs between G-CSF primed and unprimed groups were determined (p<0.05, fold change ±1.5).

A total of 2156 miRNAs were upregulated whereas 2436 miRNAs were downregulated after in-vivo G-CSF priming. The expression of hp_hsa-mir-1238 and has-miR-3180-3p non-coding RNAs was significantly increased in G-CSF primed BM-MSCs (p<0.001). Modular enrichment analysis of hsa-miR-3180-3p predicted target genes by GeneCodis 3 software revealed that some may play a role in different types of cancer such as small cell lung cancer (Adjusted p-value: 8.47338e-7, 0.000382029). Our data indicate that G-CSF treatment changes miRNA expression of bone marrow stromal cells (MSCs) and this change might be important to evaluate for long-term biosafety.