title: 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 = 63) from untreated and patients exposed to hormonal therapies (GnRH agonist, 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 and the leiomyosarcoma cell line. At tissue level leiomyomas expressed significantly lower levels of miR-93 and elevated MCM7 as compared with 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 a microarray analysis, tissue factor (F3) and IL8 were identified as their possible targets. At the tissue level, leiomyomas expressed a significantly lower level of F3 and an elevated IL-8 level, which exhibited an inverse relationship with miR-93 but with limited racial or hormonal influences. The gain of function of miR-93/106b in leiomyoma smooth muscle cells, myometrial smooth muscle cells, and the leiomyosarcoma cell line dose dependently repressed F3 and IL8 through direct interactions with their respective 3'-untranslated region and indirectly through F3 repression inhibited IL8, CTGF, and PAI-1 expression, confirmed by using small interfering RNA 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, IL8, 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.
authors.affiliation: Department of Obstetrics and Gynecology, University of Florida, Gainesville, FL 32610, USA.
authors.forename: Tsai-Der
authors.initials: TD
authors.lastname: Chuang
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Luo
authors.forename: Harekrushna
authors.initials: H
authors.lastname: Panda
authors.forename: Nasser
authors.initials: N
authors.lastname: Chegini
mesh_terms: D000328:Adult; D020169:Caspases / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D049109:Cell Proliferation; D002470:Cell Survival; D002478:Cells, Cultured; D016000:Cluster Analysis; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D016209:Interleukin-8 / Q000235:genetics*; D007889:Leiomyoma / Q000378:metabolism*; D008597:Menstrual Cycle; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D064168:Minichromosome Maintenance Complex Component 7; D009215:Myometrium / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference; D013925:Thromboplastin / Q000235:genetics*; D014594:Uterine Neoplasms / Q000378:metabolism*; D055815:Young Adult
chemical_list: C508606:CXCL8 protein, human; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D016209:Interleukin-8; C542541:MIRN106 microRNA, human; C543350:MIRN93 microRNA, human; D035683:MicroRNAs; D009687:Nuclear Proteins; D013925:Thromboplastin; D020169:Caspases; C101624:MCM7 protein, human; D064168:Minichromosome Maintenance Complex Component 7