The role of the AMOP domain in MUC4/Y-promoted tumour angiogenesis and metastasis in pancreatic cancer.
MUC4 is a high molecular weight membrane protein that is overexpressed in pancreatic cancer (PC) and is associated with the development and progression of this disease. However, the exact mechanisms through which MUC4 domains promote these biological processes have rarely been studied, partly because of its high molecular weight, difficulty to overexpress it. Here, we use MUC4/Y, one of the MUC4 transcript variants, as a model molecule to investigate the AMOP-domain of MUC4(MUC/Y).



We used cell proliferation, migration, invasion and tube formation assays in vitro to explore the abilities of AMOP domain in PC. In vivo, the matrigel plug assay, orthotopic implantation and Kaplan-Meier survival curves were used to check the results we observed in vitro. Finally, we discovered the underlying mechanism through western blot and immunofluorescence.



We found that MUC4/Y overexpression could enhance the angiogenic and metastatic properties of PC cells, both in vitro and in vivo. However, the deletion of AMOP domain could cutback these phenomena. Additionally, Kaplan-Meier survival curves showed that mice injected with MUC4/Y overexpressed cells had shorter survival time, compared with empty-vector-transfected cells (MUC4/Y-EV), or cells expressing MUC4/Y without the AMOP domain (MUC4/Y-AMOP(△)). Our data also showed that overexpression of MUC4/Y could activate NOTCH3 signaling, increasing the expression of downstream genes: VEGF-A, MMP-9 and ANG-2.



The AMOP domain had an important role in MUC4/Y (MUC4)-mediated tumour angiogenesis and metastasis of PC cells; and the NOTCH3 signaling was involved. These findings provided new insights into PC therapies. Our study also supplies a new method to study other high molecular membrane proteins.
Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.|Department of Pediatric Surgery, Nanjing Children's Hospital Affiliated to Nanjing Medical University, Nanjing, Jiangsu, China.
Jie
J
Tang
Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
Yi
Y
Zhu
Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.|Department of General Surgery, the People's Hospital of Bozhou, Bozhou, Anhui, China.
Kunling
K
Xie
Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.|Department of General Surgery, Huai'an People's Hospital, Xuzhou Medical College, Huai'an, Jiangsu, China.
Xiaoyu
X
Zhang
Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.|Department of General Surgery, Affiliated Hospital of Nantong University, Nantong, Jiangsu, China.
Xiaofei
X
Zhi
Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
Weizhi
W
Wang
Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
Zheng
Z
Li
Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
Qun
Q
Zhang
Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
Linjun
L
Wang
Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
Jiwei
J
Wang
Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China. xuzekuan@njmu.edu.cn.
Zekuan
Z
Xu
D000818:Animals; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D051379:Mice; D055264:Mucin-4 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D009362:Neoplasm Metastasis; D009368:Neoplasm Transplantation; D010190:Pancreatic Neoplasms / Q000098:blood supply* / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D000072417:Protein Domains; D000071656:Receptor, Notch3 / Q000378:metabolism; D015398:Signal Transduction; D016019:Survival Analysis; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D033921:Vesicular Transport Proteins / Q000378:metabolism
C524658:MUC4 protein, human; D055264:Mucin-4; C499374:NOTCH3 protein, human; D000071656:Receptor, Notch3; C555023:VPS51 protein, human; D042461:Vascular Endothelial Growth Factor A; D033921:Vesicular Transport Proteins; C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2
MUC4/Y-AMOP domain; Metastasis; NOTCH3; Pancreatic cancer; Tumour angiogenesis