Kaposi's sarcoma-associated herpesvirus (KSHV), also called human herpesvirus 8, belongs to the gamma herpesviruses and is the etiological agent of
Kaposi's sarcoma,
primary effusion lymphoma, and some types of
multicentric Castleman's disease. In vivo, KSHV mainly infects B cells and endothelial cells. The interactions between KSHV and its host cells determine the outcome of
viral infection and subsequent viral pathogenesis.
MicroRNAs (
miRNAs) are small, non-coding RNAs that are important in fine-tuning cellular signaling. During
infection, KSHV modulates the expression profiles and/or functions of a number of host
miRNAs, for example
hsa-miR-132 and hsa-miR-146a. Meanwhile, KSHV itself encodes 12 pre-
miRNAs, including miR-K12-11, which is the functional ortholog of the host miR-155. A number of cellular and viral targets of deregulated cellular
miRNAs and viral
miRNAs are found in KSHV-infected cells, which suggests that
miRNAs may be important in mediating KSHV-host interactions. In this review, we summarize our current understanding of how KSHV modulates the expression and/or functions of host
miRNAs; we review in detail the functions of miR-K12-11 as the ortholog of miR-155; and we examine the functions of viral
miRNAs in KSHV life cycle control, immune evasion, and pathogenesis.