title: Decrease of miR-622 expression suppresses migration and invasion by targeting regulation of DYRK2 in colorectal cancer cells.
abstract: BACKGROUND
  More and more evidence indicates that microRNAs are present and involved in many tumor-related diseases. The function of microRNA-622 (miR-622) in colorectal cancer (CRC) remains controversial. Dual specificity tyrosine phosphorylation-regulated kinase 2 (DYRK2) has been reported as a tumor suppressor gene in different cancers. The detailed regulation mechanism of DYRK2 in CRC remains unclear.
  
  
  METHODS
  miR-622 and DYRK2 expression levels were detected at tissue and cellular level respectively by using real time polymerase chain reaction (PCR), Western blot, and immunohistochemical staining. Pearson's correlation analysis was used to evaluate the correlation between miR-622 and DYRK2. Transwell assay was applied to measure the effect of miR-622 on migration and invasion of SW1116 and SW480. We used dual luciferase reporter assay to confirm the targeted binding effect of miR-622 and DYRK2 3'-untranslated region (3'UTR). An antisense experiment was executed to further confirm the role miR-622 had played with regard to migration and invasion by targeting regulation of DYRK2 pathway in CRC cells.
  
  
  RESULTS
  In our research, we found that the expression of miR-622 was elevated in CRC tissues and cell lines compared to that of nonCRC tissues and the normal human colon epithelial cell line NCM460. Correspondingly, the expression of DYRK2 in CRC tissues and cell lines showed a contrary tendency. The different expression level of DYRK2 was closely correlated with clinicopathological characteristics of CRC patients. We demonstrated that down-regulation of miR-622 could inhibit the ability of migration and invasion of CRC cell lines SW1116 and SW480. Also, we confirmed that DYRK2 was negatively regulated by miR-622 via a specific targeted binding site within the 3'UTR. We finally verified that the migration and invasion ability of CRC cells in the conducted DYRK2 3'UTR defect plasmid transfection group were lower compared to miR-622 and cotransfection group.
  
  
  CONCLUSIONS
  The findings of this study indicate that a decrease of miR-622 expression could suppress migration and invasion by targeting regulation of DYRK2 and miR-622/DYRK2 could be a potential molecular treating target of CRC.
authors.affiliation: The 4th Department of Orthopedic Surgery, Central Hospital affiliated to Shenyang Medical College, Shenyang.
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Pathology, Central Hospital affiliated to Shenyang Medical College, Shenyang.
authors.forename: Jie
authors.initials: J
authors.lastname: Sun
authors.affiliation: The 3rd Department of General Surgery, Central Hospital affiliated to Shenyang Medical College, Shenyang.
authors.forename: Xilin
authors.initials: X
authors.lastname: Wei
authors.affiliation: Department of Pathology, Central Hospital affiliated to Shenyang Medical College, Shenyang.
authors.forename: Lan
authors.initials: L
authors.lastname: Luan
authors.affiliation: Department of Surgical Oncology, Central Hospital affiliated to Shenyang Medical College, Shenyang, People's Republic of China.
authors.forename: Xiandong
authors.initials: X
authors.lastname: Zeng
authors.affiliation: Department of Pathology, Central Hospital affiliated to Shenyang Medical College, Shenyang.
authors.forename: Cuifang
authors.initials: C
authors.lastname: Wang
authors.affiliation: The 4th Department of Orthopedic Surgery, Central Hospital affiliated to Shenyang Medical College, Shenyang.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhao
keywords: DYRK2; colorectal cancer; invasion; miR-622; migration