title: MicroRNA-200 is commonly repressed in conjunctival MALT lymphoma, and targets cyclin E2.
abstract: BACKGROUND
  Aberrant microRNA expression is implicated in cancer initiation and progression. We sought to identify dysregulated miRNAs in conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma, and investigated their biological significance.
  
  
  METHODS
  The profiles of miRNAs in conjunctival MALT lymphoma and normal adjacent tissues were investigated by microRNA microarray of four pairs of surgically removed conjunctival MALT lymphoma tissues and matched controls. The results of microarray were further confirmed in 14 paired conjunctival MALT lymphoma samples (including the former four pairs) using quantitative RT-PCR. The functional effect of miR-200 was examined further. A luciferase reporter assay was performed to confirm the predicted target.
  
  
  RESULTS
  The microarray results revealed upregulated miR-150/155, and downregulated miR-184, miR-200a, b, c, and miR-205. These findings were confirmed by quantitative RT-PCR. Targetscan analysis suggested cyclin E2 as potential target of miR-200a, b, c. Luciferase reporter assay using vectors containing the 3'UTR of cyclin E2 showed that miR-200a, b, c could suppress luciferase activities. RT-PCR and immunoblotting studies revealed that overexpression of miR-200a, b, c reduced the mRNA and protein levels of cyclin E2 respectively.
  
  
  CONCLUSIONS
  We demonstrated that miRNAs were dysregulated in conjunctival MALT lymphoma, and dysregulation of the miR-200 family could be involved in the pathogenesis and progression of the disease.
authors.affiliation: Department of Ophthalmology of Shanghai Changzheng Hospital, Second Military Medical University, 415 Fengyang Road, Shanghai, 200003, People's Republic of China.
authors.forename: Jiping
authors.initials: J
authors.lastname: Cai
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Liu
authors.forename: Jinwei
authors.initials: J
authors.lastname: Cheng
authors.forename: You
authors.initials: Y
authors.lastname: Li
authors.forename: Xiao
authors.initials: X
authors.lastname: Huang
authors.forename: Yuzhen
authors.initials: Y
authors.lastname: Li
authors.forename: Xiaoye
authors.initials: X
authors.lastname: Ma
authors.forename: Hongyu
authors.initials: H
authors.lastname: Yu
authors.forename: Huimin
authors.initials: H
authors.lastname: Liu
authors.forename: Ruili
authors.initials: R
authors.lastname: Wei
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015153:Blotting, Western; D003230:Conjunctival Neoplasms / Q000235:genetics* / Q000473:pathology; D016213:Cyclins / Q000235:genetics*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology*; D057809:HEK293 Cells; D006801:Humans; D007124:Immunoenzyme Techniques; D018442:Lymphoma, B-Cell, Marginal Zone / Q000235:genetics* / Q000473:pathology; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D020411:Oligonucleotide Array Sequence Analysis; D060888:Real-Time Polymerase Chain Reaction
chemical_list: C503688:CCNE2 protein, human; D016213:Cyclins; C533896:MIRN200 microRNA, human; D035683:MicroRNAs