Abstract

ABSTRACT Programmed cell death-ligand 1 (PD-L1) is a glycoprotein that is expressed on the cell surface of both hema-topoietic and nonhematopoietic cells. PD-L1 play a role in the immune tolerance and protect self-tissues fromimmune system attack. Dysfunction of this molecule has been highlighted in the pathogenesis of tumors, au-toimmunity, and infectious disorders. MicroRNAs (miRNAs) are endogenous molecules that are classified assmall non-coding RNA with approximately 20–22 nucleotides (nt) length. The function of miRNAs is based oncomplementary interactions with target mRNA via matching completely or incompletely. The result of thisfunction is decay of the target mRNA or preventing mRNA translation. In the past decades, several miRNAs havebeen discovered which play an important role in the regulation of PD-L1 in various malignancies. In this review,we discuss the effect of miRNAs on PD-L1 expression and consider the effect of miRNAs on the synthetic pathwayof PD-L1, especially during cancers