Serial selection for invasiveness increases expression of miR-143/miR-145 in glioblastoma cell lines

Abstract

BackgroundGlioblastoma multiforme (GBM) is the most common primary central nervous system malignancy and its unique invasiveness renders it difficult to treat. This invasive phenotype, like other cellular processes, may be controlled in part by microRNAs - a class of small non-coding RNAs that act by altering the expression of targeted messenger RNAs. In this report, we demonstrate a straightforward method for creating invasive subpopulations of glioblastoma cells (IM3 cells). To understand the correlation between the expression of miRNAs and the invasion, we fully profiled 1263 miRNAs on six different cell lines and two miRNAs, miR-143 and miR-145, were selected for validation of their biological properties contributing to invasion. Further, we investigated an ensemble effect of both miR-143 and miR-145 in promoting invasion.MethodsBy repeated serial invasion through Matrigel®-coated membranes, we isolated highly invasive subpopulations of glioma cell lines. Phenotypic characterization of these cells included in vitro assays for proliferation, attachment, and invasion. Micro-RNA expression was compared using miRCURY arrays (Exiqon). In situ hybridization allowed visualization of the regional expression of miR-143 and miR-145 in tumor samples, and antisense probes were used investigate in vitro phenotypic changes seen with knockdown in their expression.ResultsThe phenotype we created in these selected cells proved stable over multiple passages, and their microRNA expression profiles were measurably different. We found that two specific microRNAs expressed from the same genetic locus, miR-143 and miR-145, were over-expressed in our invasive subpopulations. Further, we also found that combinatorial treatment of these cells with both antisense-miRNAs (antimiR-143 and -145) will abrogated their invasion without decreasing cell attachment or proliferation.ConclusionsTo best of our knowledge, these data demonstrate for the first time that miR-143 and miR-145 regulate the invasion of glioblastoma and that miR-143 and -145 could be potential therapeutic target for anti-invasion therapies of glioblastoma patients.

MicroRNAs as efficient biomarkers in high-grade gliomas

“…The other upregulated microRNA in highly aggressive GBM cell lines is microRNA-145 [30]. That fact promotes decreased proliferation and invasion of GBM cell lines [33].…”

MicroRNAs in cancer: Glioblastoma and glioblastoma cancer stem cells

“…Evidence has also demonstrated malignant cells to exhibit widespread dysregulation of microRNAs compared to normal cells (Chan et al, 2005; Ciafre et al, 2005). A large number of subsequent studies have demonstrated a role for microRNAs in tumorigenesis (Chan et al, 2005; Ciafre et al, 2005; Esquela-Kerscher and Slack, 2006; He et al, 2005; Koo et al, 2012; Lavon et al, 2010). …”

“…Another microRNA with conflicting data regarding expression levels in GBM when compared to non-neoplastic tissues is miR-145 (Koo et al, 2012). Koo et al (2012) demonstrated miR-145 upregulation in a number of highly aggressive GBM cell lines (Koo et al, 2012).…”

“…Koo et al (2012) demonstrated miR-145 upregulation in a number of highly aggressive GBM cell lines (Koo et al, 2012). This group further reported that the downregulation of miR-145 led to decreased invasive capabilities of these cell lines.…”

miR-204 inhibits the proliferation and invasion of renal cell carcinoma by inhibiting RAB22A expression

“…Recent studies have demonstrated the regulatory functions of miRNAs in RCC cell proliferation (11)(12)(13), apoptosis (14,15), invasion and metastasis (16)(17)(18). A predominant and systemic alteration in miRNA expression during renal carcinogenesis has been indicated by studies of miRNA expression profiling (16). miR-204 is an miRNA which is enriched in germline and mesoderm-derived tissues, such as the testis, uterus, kidney, lung, heart and bladder (19).…”