MiR-93/106b and their host gene, MCM7, are differentially expressed in leiomyomas and functionally target F3 and IL-8

ABSTRACT: miR-93/106b and their host gene minichromosome maintenance complex component 7 (MCM7) reside at chr7q22, a region frequently rearranged in leiomyomas. We explored the expression of miR-93/106b in leiomyoma and paired myometrium (N=62) from untreated and patients exposed to hormonal therapies (GnRHa, Depo-Provera and oral contraceptives) from African Americans and Caucasians, and their regulatory functions in isolated paired (N=15) leiomyoma and myometrial smooth muscle cells (LSMC and MSMC) and leiomyosarcoma cell line (SKLM-S1). At tissue level leiomyomas expressed significantly lower levels of miR-93 and elevated MCM7 as compared to myometrium with limited racial influence or hormonal exposure on their expression. Assessing the regulatory function of miR-93/106b through doxycycline-inducible lentiviral transduction in microarray analysis, tissue factor (F3) and IL-8 were identified as their possible targets. At tissue level leiomyomas expressed a significantly lower level of F3 and an elevated IL-8 which exhibited an inverse relationship with miR-93, but with limited racial or hormonal influences. Gain-of-function of miR-93/106b in LSMC, MSMC and SKLM-S1 dose-dependently repressed F3 and IL-8 through direct interactions with their respective 3’UTRs and indirectly through F3 repression inhibited IL8, CTGF and PAI-1 expression, confirmed by using siRNA silencing or factor Vlla (FVIIa) activation of F3, as well as reducing the rate of proliferation, while increasing caspase 3/7 activity. We concluded that differential expression of miR-93/106b and their direct and/or indirect regulatory functions on F3, IL-8, CTGF and PAI-1 expression, with key roles in inflammation and tissue turnover may be of significance in the outcome of leiomyoma growth and associated symptoms.

ORGANISM(S): Homo sapiens

PROVIDER: GSE37122 | GEO | 2012/04/10

SECONDARY ACCESSION(S): PRJNA158405

REPOSITORIES: GEO