Table 1 Aberrant miRNAs involved in pathogenesis or drug resistance of MM

miR-21

Upregulation

Inhibition of apoptosis and increase drug resistance

[74]

miR-125b

Upregulation

Reduction of cell death in dexamethasone induced MM (drug resistance)

[75]

miR-15a

miR-16

Downregulation

Regulation of MM cell proliferation in vitro and in vivo

Downregulated in patients with relapsed/refractory disease (drug resistance)

[76, 77]

miR-221/222

Upregulation

Inhibition of apoptosis and modulation of drug influx-efflux and ABC transporters (drug resistance)

[36]

miR-27a

Downregulation

Downregulated in MM patients with bortezomib-refractory status (drug resistance)

[46]

miR-149

Downregulation

Downregulated in glucocorticoid resistant MM cells by disturbing epigenetic landscape, leading to overexpression of MMP-9 gene which is involved in bone remodeling and tumor invasion in MM

[78]

miR-631

Downregulation

Modulates UbcH10/MDR1 pathway which is associated with the development of BTZ resistance in myeloma cells

[79]

miR-202

Downregulation

Involved on drug resistance of MM cells by targeting JNK/SAPK signaling pathway

[80]

miR-30c

Downregulation

Downregulated as a result of interaction between MM cells and bone marrow stromal cells, which in turn activation of oncogenic Wnt/β-catenin/BCL9 pathway and promote MM cell proliferation, drug resistance and formation of MM cancer stem cells.

[81]

miR-137/197

Downregulation

Modulates MCL-1 which is dysregulated in multiple myeloma cells and overexpression of MCL-1 is associated with relapse and poor survival

[51]

miR-17-92 cluster

miR-106~363 cluster

Upregulation

High level is associated with shorter overall survival

[82]

miR-148a & miR-20a

Upregulation

Shorter relapse-free survival

[83]

let-7e, miR-125a-5p, and miR-99b cluster

Upregulation

Overexpression in t(4;14) patients

[84]

miR-140-3p

Downregulation

Altered expression due to the occurrence of several allelic imbalances or loss of heterozygosity in 16q2 region

[84]

miR-32 and miR-17~92 cluster

Upregulation

Upregulated in MM patients and cell lines but not in MGUS or healthy PCs

[85]

miR-19a and 19b

Upregulation

Inhibition of IL-6 growth signaling

[85]

miR106b~25 cluster, miR-181a/b, miR-32

Upregulation

Targeting of the genes which involved in p53 regulation

[85]

miR-1/miR-133a cluster

Upregulation

Overexpressed in MM patients with t(14;16)

[86]

miR-135b and miR-146a

Downregulation

Downregulated in MM with t(4;14) and targeted the genes which are involved in IL-1 signaling pathway

[86]

miR-214

Downregulation

Positive regulation of P53 and inhibition of DNA replication

[87]

miR-29b

Downregulation

Reduction of apoptosis by upregulation of MCL1

[88]

miR-192, miR-194, miR-215

Downregulation

p53-inducible microRNAs which modulate MDM2 expression regulate IGF pathway and enhance migration of plasma cells into bone marrow

[89]