The online version of this article (doi:10.1186/1476-4598-11-44) contains supplementary material, which is available to authorized users.
Yechezkel Sidi, Dror Avni contributed equally to this work.
There are no financial or non-financial competing interests to declare.
LZ performed the molecular biology and tissue culture experiments; RA performed the micro-array experiments (with LZ); AB and DB performed the experiments with the pathological material; RN performed the bioinformatic and statistical analyses; LZ, YS, DA and RLA designed the experiments, analyzed the data and prepared the manuscript. All authors read and approved the final manuscript.
Metastatic melanoma is a devastating disease with limited therapeutic options. MicroRNAs (miRNAs) are small non coding RNA molecules with important roles in post-transcriptional gene expression regulation, whose aberrant expression has been implicated in cancer.
We show that the expression of miRNAs from a large cluster on human chromosome 14q32 is significantly down-regulated in melanoma cell lines, benign nevi and melanoma samples relative to normal melanocytes. This miRNA cluster resides within a parentally imprinted chromosomal region known to be important in development and differentiation. In some melanoma cell lines, a chromosomal deletion or loss-of-heterozygosity was observed in the cis-acting regulatory region of this cluster. In several cell lines we were able to re-express two maternally-induced genes and several miRNAs from the cluster with a combination of de-methylating agents and histone de-acetylase inhibitors, suggesting that epigenetic modifications take part in their silencing. Stable over-expression of mir-376a and mir-376c, two miRNAs from this cluster that could be re-expressed following epigenetic manipulation, led to modest growth retardation and to a significant decrease in migration in-vitro. Bioinformatic analysis predicted that both miRNAs could potentially target the 3'UTR of IGF1R. Indeed, stable expression of mir-376a and mir-376c in melanoma cells led to a decrease in IGF1R mRNA and protein, and a luciferase reporter assay indicated that the 3'UTR of IGF1R is a target of both mir-376a and mir-376c.
Our work is the first to show that the large miRNA cluster on chromosome 14q32 is silenced in melanoma. Our results suggest that down-regulation of mir-376a and mir-376c may contribute to IGF1R over-expression and to aberrant negative regulation of this signaling pathway in melanoma, thus promoting tumorigenesis and metastasis.
Additional file 1: The expression levels of miRNAs in normal melanocytes and melanoma cell lines. (XLSX 68 KB)12943_2012_1024_MOESM1_ESM.xlsx
Additional file 2: The expression levels of miRNAs in normal melanocytes, benign nevi and melanoma samples. (XLSX 92 KB)12943_2012_1024_MOESM2_ESM.xlsx
Additional file 3: The expression levels of miRNAs in melanoma cell lines in response to epigenetic modifiers. (XLSX 59 KB)12943_2012_1024_MOESM3_ESM.xlsx
Authors’ original file for figure 112943_2012_1024_MOESM4_ESM.pdf
Authors’ original file for figure 212943_2012_1024_MOESM5_ESM.pdf
Authors’ original file for figure 312943_2012_1024_MOESM6_ESM.pdf
Authors’ original file for figure 412943_2012_1024_MOESM7_ESM.pdf
Zhang L, Volinia S, Bonome T, Calin GA, Greshock J, Yang N, Liu CG, Giannakakis A, Alexiou P, Hasegawa K: Genomic and epigenetic alterations deregulate microRNA expression in human epithelial ovarian cancer. Proc Natl Acad Sci USA. 2008, 105: 7004-7009. 10.1073/pnas.0801615105 PubMedCentralCrossRefPubMed
Haller F, von Heydebreck A, Zhang JD, Gunawan B, Langer C, Ramadori G, Wiemann S, Sahin O: Localization- and mutation-dependent microRNA (miRNA) expression signatures in gastrointestinal stromal tumours (GISTs), with a cluster of co-expressed miRNAs located at 14q32.31. J Pathol. 2010, 220: 71-86. 10.1002/path.2610 CrossRefPubMed
Kagami M, O'Sullivan MJ, Green AJ, Watabe Y, Arisaka O, Masawa N, Matsuoka K, Fukami M, Matsubara K, Kato F: The IG-DMR and the MEG3-DMR at human chromosome 14q32.2: hierarchical interaction and distinct functional properties as imprinting control centers. PLoS Genet. 2010, 6: e1000992- 10.1371/journal.pgen.1000992 PubMedCentralCrossRefPubMed
Zalaudek I, Guelly C, Pellacani G, Hofmann-Wellenhof R, Trajanoski S, Kittler H, Scope A, Marghoob AA, Longo C, Leinweber B: The dermoscopical and histopathological patterns of nevi correlate with the frequency of BRAF mutations. J Invest Dermatol. 2011, 131: 542-545. 10.1038/jid.2010.332 CrossRefPubMed
Resnicoff M, Coppola D, Sell C, Rubin R, Ferrone S, Baserga R: Growth inhibition of human melanoma cells in nude mice by antisense strategies to the type 1 insulin-like growth factor receptor. Cancer Res. 1994, 54: 4848-4850. PubMed
Villanueva J, Vultur A, Lee JT, Somasundaram R, Fukunaga-Kalabis M, Cipolla AK, Wubbenhorst B, Xu X, Gimotty PA, Kee D: Acquired resistance to BRAF inhibitors mediated by a RAF kinase switch in melanoma can be overcome by cotargeting MEK and IGF-1R/PI3K. Cancer Cell. 2010, 18: 683-695. 10.1016/j.ccr.2010.11.023 PubMedCentralCrossRefPubMed
Lehmann F, Marchand M, Hainaut P, Pouillart P, Sastre X, Ikeda H, Boon T, Coulie PG: Differences in the antigens recognized by cytolytic T cells on two successive metastases of a melanoma patient are consistent with immune selection. Eur J Immunol. 1995, 25: 340-347. 10.1002/eji.1830250206 CrossRefPubMed
Besser MJ, Treves AJ, Itzhaki O, Hardan I, Nagler A, Papa MZ, Catane R, Winkler E, Shalmon-Zifroni B, Schachter J: Adoptive cell therapy for metastatic melanoma patients: pre-clinical development at the Sheba Medical Center. Isr Med Assoc J. 2006, 8: 164-168. PubMed
van de Wetering M, Oving I, Muncan V, Pon Fong MT, Brantjes H, van Leenen D, Holstege FC, Brummelkamp TR, Agami R, Clevers H: Specific inhibition of gene expression using a stably integrated, inducible small-interfering-RNA vector. EMBO Rep. 2003, 4: 609-615. 10.1038/sj.embor.embor865 PubMedCentralCrossRefPubMed
- Silencing of a large microRNA cluster on human chromosome 14q32 in melanoma: biological effects of mir-376a and mir-376c on insulin growth factor 1 receptor
- BioMed Central
Neu im Fachgebiet Onkologie
Mail Icon II