Inhibition of microRNA-17/20a suppresses cell proliferation in gastric cancer by modulating UBE2C expression.

microRNAs (miRNAs) are small non-coding RNAs that potentially play a critical role in carcinogenesis. Increasing evidence indicates that the miR-17/20 cluster is upregulated in numerous types of human cancers including gastric cancer which suggests that the miR-17/20 cluster may play an important role in tumorigenesis. However, its role in gastric cancer carcinogenesis remains poorly defined due to the lack of target gene information. The aim of the present study was to investigate the target genes of the miR-17/20 cluster and their role in the tumor growth of gastric cancer. We found that both miR-17 and miR-20a (miR-17/20a) target the UBE2C gene in gastric cancer cells. Luciferase assay, qRT-PCR and western blot analysis confirmed that UBE2C is a direct target of miR‑17/20a in gastric cancer cells. Our results showed that the expression of UBE2C was positively regulated by miR-17/20a at both the mRNA and protein levels. Moreover, miR-17/20a was upregulated and positively associated with UBE2C in the gastric cancer tissues when compared to the adjacent nontumor tissues. Inhibition of miR-17/20a in gastric cancer cells was statistically correlated with a decrease in cell growth. These results demonstrate that upregulation of miR-17/20a promotes gastric cancer cell growth by targeting UBE2C and inhibition of their levels is a potentially promising therapeutic strategy for gastric cancer.

[1]  K. Zen,et al.  MicroRNA-17/20a/106a modulate macrophage inflammatory responses through targeting signal-regulatory protein α. , 2013, The Journal of allergy and clinical immunology.

[2]  Marc W. Kirschner,et al.  Autonomous regulation of the anaphase-promoting complex couples mitosis to S-phase entry , 2004, Nature.

[3]  W. Filipowicz,et al.  Regulation of mRNA translation and stability by microRNAs. , 2010, Annual review of biochemistry.

[4]  Akira Nakagawara,et al.  UbcH10 is the cancer-related E2 ubiquitin-conjugating enzyme. , 2003, Cancer research.

[5]  Nan Li,et al.  MicroRNA-466l Upregulates IL-10 Expression in TLR-Triggered Macrophages by Antagonizing RNA-Binding Protein Tristetraprolin-Mediated IL-10 mRNA Degradation , 2010, The Journal of Immunology.

[6]  J. Gudmundsson,et al.  Mapping loss of heterozygosity at chromosome 13q: loss at 13q12-q13 is associated with breast tumour progression and poor prognosis. , 1998, European journal of cancer.

[7]  M. Kuo,et al.  MicroRNA-17/20a functions to inhibit cell migration and can be used a prognostic marker in oral squamous cell carcinoma. , 2013, Oral oncology.

[8]  Huan Sun,et al.  The miR-17-92 cluster regulates FOG-2 expression and inhibits proliferation of mouse embryonic cardiomyocytes , 2012, Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas.

[9]  F. Slack,et al.  Small non-coding RNAs in animal development , 2008, Nature Reviews Molecular Cell Biology.

[10]  D. Tollervey,et al.  Mapping the Human miRNA Interactome by CLASH Reveals Frequent Noncanonical Binding , 2013, Cell.

[11]  D. Lockhart,et al.  Analysis of gene expression profiles in normal and neoplastic ovarian tissue samples identifies candidate molecular markers of epithelial ovarian cancer. , 2001, Proceedings of the National Academy of Sciences of the United States of America.

[12]  Kathryn A. O’Donnell,et al.  c-Myc-regulated microRNAs modulate E2F1 expression , 2005, Nature.

[13]  Jie Zhou,et al.  microRNA 17/20 inhibits cellular invasion and tumor metastasis in breast cancer by heterotypic signaling , 2010, Proceedings of the National Academy of Sciences.

[14]  D. Bartel.  MicroRNAs Genomics, Biogenesis, Mechanism, and Function , 2004, Cell.

[15]  Terry Hyslop,et al.  A cyclin D1/microRNA 17/20 regulatory feedback loop in control of breast cancer cell proliferation , 2008, The Journal of cell biology.

[16]  Ling Yang,et al.  Incidence and mortality of gastric cancer in China. , 2006, World journal of gastroenterology.

[17]  Yaou Zhang,et al.  MicroRNA MiR-17 retards tissue growth and represses fibronectin expression , 2009, Nature Cell Biology.

[18]  R. Labianca,et al.  Gastric cancer. , 2009, Critical reviews in oncology/hematology.

[19]  林下 陽二.  A polycistronic microRNA cluster, miR-17-92, is overexpressed in human lung cancers and enhances cell proliferation , 2006 .

[20]  A. Jemal,et al.  Global Cancer Statistics , 2011 .

[21]  M. Kruhøffer,et al.  UbcH10 overexpression may represent a marker of anaplastic thyroid carcinomas , 2005, British Journal of Cancer.

[22]  E. Latulippe,et al.  Comprehensive gene expression analysis of prostate cancer reveals distinct transcriptional programs associated with metastatic disease. , 2002, Cancer research.

[23]  Jun Yu,et al.  MicroRNA dysregulation in gastric cancer: a new player enters the game , 2010, Oncogene.

[24]  D. Parkin,et al.  Global cancer statistics in the year 2000. , 2001, The Lancet. Oncology.

[25]  Francesco Hofmann,et al.  Overexpression, genomic amplification and therapeutic potential of inhibiting the UbcH10 ubiquitin conjugase in human carcinomas of diverse anatomic origin , 2004, Oncogene.

[26]  Hirokuni Ikeda,et al.  Clinicopathological relevance of UbcH10 in breast cancer , 2009, Cancer science.

[27]  C. Croce,et al.  MiRNAs and cancer. , 2009, The American journal of pathology.

[28]  P. Malfertheiner,et al.  Macro-Role of MicroRNA in Gastric Cancer , 2012, Digestive Diseases.

[29]  G. Pijlman,et al.  West Nile virus encodes a microRNA-like small RNA in the 3′ untranslated region which up-regulates GATA4 mRNA and facilitates virus replication in mosquito cells , 2011, Nucleic acids research.

[30]  Cheng-guang Huang,et al.  Knockdown of ubiquitin-conjugating enzyme E2C/UbcH10 expression by RNA interference inhibits glioma cell proliferation and enhances cell apoptosis in vitro , 2010, Journal of Cancer Research and Clinical Oncology.

[31]  Chen Huang,et al.  MicroRNA profiling of human gastric cancer. , 2009, Molecular medicine reports.

[32]  G. Tamura.  Genetic and epigenetic alterations of tumor suppressor and tumor-related genes in gastric cancer. , 2002, Histology and histopathology.

[33]  Tsung-Hsien Chang,et al.  Ubiquitin-Conjugating Enzyme UBE2C Is Highly Expressed in Breast Microcalcification Lesions , 2014, PloS one.

[34]  S. Lowe,et al.  A microRNA polycistron as a potential human oncogene , 2005, Nature.