title: miR-192, miR-194 and miR-215: a convergent microRNA network suppressing tumor progression in renal cell carcinoma.
abstract: MicroRNAs (miRNAs) play a crucial role in tumor progression and metastasis. We, and others, recently identified a number of miRNAs that are dysregulated in metastatic renal cell carcinoma compared with primary renal cell carcinoma. Here, we investigated three miRNAs that are significantly downregulated in metastatic tumors: miR-192, miR-194 and miR-215. Gain-of-function analyses showed that restoration of their expression decreases cell migration and invasion in renal cell carcinoma cell line models, whereas knockdown of these miRNAs resulted in enhancing cellular migration and invasion abilities. We identified three targets of these miRNAs with potential role in tumor aggressiveness: murine double minute 2, thymidylate synthase, and Smad Interacting protein 1/zinc finger E-box binding homeobox 2. We observed a convergent effect (the same molecule can be targeted by all three miRNAs) and a divergent effect (the same miRNA can control multiple targets) for these miRNAs. We experimentally validated these miRNA-target interactions using three independent approaches. First, we observed that miRNA overexpression significantly reduces the mRNA and protein levels of their targets. In the second, we observed significant reduction of the luciferase signal of a vector containing the 3'UTR of the target upon miRNA overexpression. Finally, we show the presence of inverse correlation between miRNA changes and the expression levels of their targets in patient specimens. We also examined the prognostic significance of miR-215 in renal cell carcinoma. Lower expression of miR-215 is associated with significantly reduced disease-free survival time. These findings were validated on an independent data set from The Cancer Genome Atlas. These results can pave the way to the clinical use of miRNAs as prognostic markers and therapeutic targets.
authors.affiliation: Department of Laboratory Medicine and the Keenan Research Centre, Li Ka Shing Knowledge Institute of St. Michael's Hospital, 30 Bond Street, Toronto, Ontario M5B 1W8, Canada.
authors.forename: H W Z
authors.initials: HW
authors.lastname: Khella
authors.forename: M
authors.initials: M
authors.lastname: Bakhet
authors.forename: G
authors.initials: G
authors.lastname: Allo
authors.forename: M A S
authors.initials: MA
authors.lastname: Jewett
authors.forename: A H
authors.initials: AH
authors.lastname: Girgis
authors.forename: A
authors.initials: A
authors.lastname: Latif
authors.forename: H
authors.initials: H
authors.lastname: Girgis
authors.forename: I
authors.initials: I
authors.lastname: Von Both
authors.forename: G A
authors.initials: GA
authors.lastname: Bjarnason
authors.forename: G M
authors.initials: GM
authors.lastname: Yousef
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics; D002292:Carcinoma, Renal Cell / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics; D049109:Cell Proliferation; D018450:Disease Progression; D015870:Gene Expression; D015972:Gene Expression Regulation, Neoplastic; D053263:Gene Regulatory Networks; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007680:Kidney Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D035683:MicroRNAs / Q000235:genetics*; D009361:Neoplasm Invasiveness; D011379:Prognosis; D051736:Proto-Oncogene Proteins c-mdm2 / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D000074165:Zinc Finger E-box Binding Homeobox 2
chemical_list: D014408:Biomarkers, Tumor; D018398:Homeodomain Proteins; C546783:MIRN192 microRNA, human; C554846:MIRN194 microRNA, human; C553667:MIRN215 microRNA, human; D035683:MicroRNAs; D012097:Repressor Proteins; C492363:ZEB2 protein, human; D000074165:Zinc Finger E-box Binding Homeobox 2; D051736:Proto-Oncogene Proteins c-mdm2