miR-337 regulates the proliferation and invasion in pancreatic ductal adenocarcinoma by targeting HOXB7
Authors: Wenqiao Zang
Junwen Huang
Hong Leng
Guoqiang Zhao
Yuwen Du
Xiaonan Chen
Rui Zhang
Yuanyuan Wang
Journal: Diagnostic Pathology (2014)
Discipline: CLINICAL MEDICINE
Keywords: miRNAs; cellular processes; target genes; pancreatic ductal adenocarcinoma; miR-337
Affiliations: Department of emergency, the First Affiliated Hospital of Zhengzhou University, No,1 Jianshe Road, Zhengzhou 450052, Henan, China. .

Abstract:  Background: miRNAs are involved in coordinating a variety of cellular processes by regulating their target genes. Aberrant expression of miRNAs is correlated with various cancers. Previous studies have shown that miR-337 is significantly down-regulated in pancreatic ductal adenocarcinoma (PDAC) and that its expression is negatively correlated to the expression of HOXB7. Both miR-337 and HOXB7 are associated with the prognosis of PDAC patients. The purpose of this study was to identify the molecular mechanisms by which miR-337 acts as a tumor suppressor in PDAC. Methods: Synthetic miR-337 mimics were transfected into PANC-1 and As-PC-1 cells using Lipofectamine™ 2000. The expression of HOXB7 protein was analyzed by Western blot. Luciferase reporter plasmids were constructed to confirm that HOXB7 3'UTR was the target of miR-337. The effect of miR-337 on cell proliferation was evaluated by CCK8 assay and colony formation assay, and cell invasion was evaluated by wound healing assay and transwell assay. Results: Western blot and luciferase activity assays identified HOXB7 as the target of miR-337. A CCK-8 assay showed the absorbance of cells transfected with miR-337 mimics to be less than that of control cells, and that the number of cell clones was significantly decreased by miR-337 expression. A wound healing assay showed the invasion rate of cells transfected with miR-337 mimics at 36 h to be markedly lower than in controls. The average number of cells penetrating the Matrigel was significantly lower than the controls. Conclusion: These findings suggest that miR-337 targets HOXB7 and effects significant suppression of PDAC cell proliferation and invasion. Virtual slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_171. 

Retracted: No

PubPeer comments:
 Top:  Figure 3 miR-337 reduced cell invasion in vitro. The effects of miR-337 mimics (or NC) on the proliferation of PANC-1 and As-PC-1 cells in vitro were detected by wound healing assay and transwell invasion assay. A) PANC-1 and As-PC-1 cells at 12 h post-transfection were seeded in six-well plates and cultured for 24 h. Confluent monolayer cells were scratched with a 200 u03bcl pipette tip and were allowed to close the wound for 36 h. Wound healing assays show the rate of invasion of PANC-1 (or As-PC-1) cells transfected with miR-337 mimics at 36 h were markedly lower than in the control groups (blank control and cells transfected with miR-337 NC).  Bottom:  Fig. 4 Invasive and migratory abilities of GC cells (BGC-823 and NCI-N87) after transfection with miR-194 were assessed by transwell assay and wound healing assay. ...c, d For BGC823 and NCI-N87, both the NC groups had a higher density of cells at 48 h after wounding compared with the miR-194 group . From  miR-194 targets RBX1 gene to modulate proliferation and migration of gastric cancer cells [(Chen et al 2015)] . ![file] Despite different cell lines and treatments, two panels overlap, as marked. , 
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