[Expression of nucleolar protein 14 and CD31 in pancreatic cancer mouse model and its correlation with tumor...

Objective: To investigate expression of nucleolar protein 14(NOP14) and CD31 in pancreatic cancer mouse model and its correlation with tumor progression. Methods: Clinicopathological data of 5 patients with pathologically confirmed pancreatic ductal adenocarcinoma(PDAC) and hepatic metastasis between January 2013 and December 2015 was collected in Department of General Surgery, Peking Union Medical College Hospital. Immunohistochemistry staining was employed to detect the expression of NOP14 in matched primary PDAC and relevant metastasis.Pancreatic cancer cells with NOP14 stably knocked down were established by transfecting lentivirus with NOP14 targeted silencing RNA.The inhibition efficacy was detected by quantitative real time PCR and western blot.Microvascular density(MVD) in pancreatic cancer transplantation mouse model was determined by CD31 immunohistochemistry staining analysis and correlated with NOP14 expression and tumor progression. Results: NOP14 had a significant higher expression in liver metastasis than primary pancreatic adenocarcinoma (2.09±0.45 vs. 1.31±0.27, P=0.028). NOP14 was knocked down 86 percent on mRNA level determined by qPCR and 78 percents on protein level detected by western blot. MVD was significantly decreased in NOP14-inhibited tumor from both pancreatic cancer cells subcutaneously and orthotopically grafted tumor mouse model with the value of 61.40±13.85 vs. 85.53±14.59 (P=0.041) and 38.33±10.91 vs. 59.33±15.37(P =0.037), respectively. Besides, MVD was positively associated with tumor volume(r=0.842, P<0.01) and metastasis (r=0.726, P=0.008). Conclusion: NOP14 presents higher expression in hepatic metastasis of pancreatic adenocarcinoma and might promote tumor progression by increasing microvascular density.