Background Chromodomain-helicase-DNA-binding protein 5 (CHD5) is a newly identified tumor suppressor that is frequently downregulated in a variety of human cancers. Our previous work revealed that the low expression of CHD5 in colorectal cancer is correlated with CHD5 promoter CpG island hypermethylation. In this study, we investigated the effect of microRNA-211 (miR-211)-regulated CHD5 expression on colorectal tumorigenesis. Methodology/Principal Findings miR-211 was predicted to target CHD5 by TargetScan software analysis. A stably expressing exogenous miR-211 colorectal cancer cell line (HCT-116miR-211) was generated using lentiviral transduction and used as a model for in vitro and in vivo studies. The expression level of miR-211 in HCT-116miR-211 cells was upregulated by 16-fold compared to vector control cells (HCT-116vector). Exogenous miR-211 directly binds to the 3′-untranslated region (3′-UTR) of CHD5 mRNA, resulting in a 50% decrease in CHD5 protein level in HCT-116miR-211 cells. The levels of cell proliferation, tumor growth, and cell migration of HCT-116miR-211 cells were significantly higher than HCT-116vector cells under both in vitro and in vivo conditions, as determined using the methods of MTT, colony formation, flow cytometry, scratch assay, and tumor xenografts, respectively. In addition, we found that enforced expression of miR-211 in HCT-116 cells was able to alter p53 pathway-associated regulatory proteins, such as MDM2, Bcl-2, Bcl-xL, and Bax. Conclusion/Significance Our results demonstrate that CHD5 is a direct target of miR-211 regulation. Enforced expression of miR-211 promotes tumor cell growth at least in part by downregulating the expression level of the CHD5 tumor suppressor. Our results provide a better understanding of the association of between miR-211-regulated CHD5 expression and CHD5 function in colorectal tumorigenesis.
References
[1]
Sudarsanam P, Winston F (2000) The Swi/Snf family nucleosome-remodeling complexes and transcriptional control. Trends Genet 16(8): 345–351.
[2]
Mokarram P, Kumar K, Brim H, Naghibalhossaini F, Saberi-firoozi M (2009) Distinct High-Profile Methylated Genes in Colorectal Cancer. PLoS One 4(9): e7012.
[3]
Woodage T, Basrai MA, Baxevanis AD, Hieter P, Collins FS (1997) Characterization of the CHD family of proteins. Proc Natl Acad Sci USA 94(21): 11472–11477.
[4]
Bagchi A, Mills AA (2008) The Quest for the 1p36 Tumor Suppressor. Cancer Res 68(8): 2551–2556.
[5]
White PS, Thompson PM, Gotoh T, Okawa ER, Igarashi J (2005) Definition and characterization of a region of 1p36.3 consistently deleted in neuroblastoma. Oncogene 24(16): 2684–2694.
[6]
Aarts M, Dannenberg H, deLeeuw RJ, van Nederveen FH, Verhofstad AA, et al. (2006) Microarray-based CGH of sporadic and syndrome-related pheochromocytomas using a 0.1–0.2 Mb bacterial artificial chromosome array spanning chromosome arm 1p. Genes Chromosomes Cancer 45(1): 83–93.
[7]
Bagchi A, Papazoglu C, Wu Y, Capurso D, Brodt M, et al. (2007) CHD5 Is a Tumor Suppressor at Human 1p36. Cell 128(3): 459–475.
[8]
Wang X, Lau KK, So LK, Lam YW (2009) CHD5 is down-regulated through promoter hypermethylation in gastric cancer. J Biomed Sci 16: 95.
[9]
Gorringe KL, Choong DY, Williams LH, Ramakrishna M, Sridhar A, et al. (2008) Mutation and Methylation Analysis of the Chromodomain-Helicase-DNA Binding 5 Gene in Ovarian Cancer. Neoplasia 10(11): 1253–1258.
[10]
Fujita T, Igarashi J, Okawa ER, Gotoh T, Manne J, et al. (2008) CHD5, a Tumor Suppressor Gene Deleted From 1p36.31 in Neuroblastomas, J Natl Cancer Inst 100(13): 940–949.
[11]
Tang YY, Tian DA, Yan W, Xia LM, Zhang lQ, et al. (2008) Involvement of CHD5 in Genesis and Development of Hepatoma as a Potent Anti-oncogene. Chin J Gastroenterol Hepatol 17(12): 994–996.
[12]
Jemal A, Siegel R, Xu J, Ward E (2010) Cancer Statistics, 2010, CA Cancer J Clin 60(5): 277–300.
[13]
Lin Y, Li YY, Nie YQ, Sha WH (2007) Quantitative Expression of Tumor Suppressor CHD5 in Colorectal Cancer Tissue, Chin J Dig 27(10): 711–712.
[14]
Mulero-Navarro S, Esteller M (2008) Chromatin remodeling factor CHD5 is silenced by promoter CpG island hypermethylation in human cancer. Epigenetics 3(4): 210–215.
[15]
Kanellopoulou C, Monticelli S (2008) A role for microRNAs in the development of the immune system and in the pathogenesis of cancer. Semin Cancer Biol 18(2): 79–88.
[16]
Voorhoeve PM, Agami R (2007) Classifying microRNAs in cancer: The good, the bad and the ugly. Biochim Biophys Acta 1775(2): 274–282.
[17]
Scholzová E, Malík R, Sevcík J, Kleibl Z (2007) RNA regulation and cancer development. Cancer Lett 246(1–2): 12–23.
[18]
Gartel AL, Kandel ES (2008) miRNAs: Little known mediators of oncogenesis. Semin Cancer Biol 18(2): 103–110.
[19]
Kim S, Choi M, Cho KH (2009) Identifying the target mRNAs of microRNAs in colorectal cancer. Comput Biol Chem 33(1): 94–99.
[20]
Lewis BP, Burge CB, Bartel DP (2005) Conserved Seed pairing, often anked by adenosines, indicates that thousands of human genes are MicroRNA targets. Cell 120(1): 15–20.
[21]
Rajewsky N (2006) microRNA target predictions in animals. Nat Genet 38: SupplS8–13.
[22]
Chang KW, Liu CJ, Chu TH, Cheng HW, Hung PS, et al. (2008) Association between High miR-211 microRNA Expression and the Poor Prognosis of Oral Carcinoma. J Dent Res 87(11): 1063–8.
[23]
Ozaki T, Nakagawara A (2011) p53: the attractive tumor suppressor in the cancer research field. J Biomed Biotechnol 603925:
[24]
Brady CA, Attardi LD (2010) p53 at a glance. J Cell Sci 123(Pt 15): 2527–2532.
[25]
Maddocks OD, Vousden KH (2010) Metabolic regulation by p53. J Mol Med 89(3): 237–245.
[26]
Ashktorab H, Sch？ffer AA, Daremipouran M (2010) Distinct genetic alterations in colorectal cancer. PLoS One 5(1): e8879.
[27]
Yantiss RK, Goodarzi M, Zhou XK (2009) Clinical, pathologic, and molecular features of early-onset colorectal carcinoma. Am J Surg Pathol 33(4): 572–582.
[28]
Hao Y, Gu X, Zhao Y, Greene S, Sha W, et al. (2011) Enforced Expression of miR-101 Inhibits Prostate Cancer Cell Growth by Modulating the COX-2 Pathway In Vivo. Cancer Prev Res (Phila) 4(7): 1073–1083.
[29]
Zhao Y, Hao Y, Ji H, Fang Y, Guo Y, et al. (2010) Combination effects of salvianolic acid B with low-dose celecoxib on inhibition of head and neck squamous cell carcinoma growth in vitro and in vivo. Cancer Prev Res (Phila) 3(6): 787–796.
[30]
Liang CC, Park AY, Guan JL (2007) In vitro scatch assay: a convenient and inexpensive method for analysis of cell migration in vitro. Nat Protoc 2(2): 329–333.
